Le blé et ses dérivés

[1] - Ebbehoj K, Dahl AM, Frokiaer H, Norgaard A, Poulsen LK, Barkholt V. Purification of egg-white allergens. Allergy 1995;50:133-141

Purification procedures for the four egg-white proteins ovomucoid, ovotransferrin, ovalbumin, and lysozyme are presented with reference to mechanistic studies at epitope levels of allergic reactions to these proteins. The applied procedures resulted in four preparations containing less than 0.1% contaminating proteins each. The purified protein preparations were characterized by SDS-PAGE and by crossed immunoelectrophoresis with polyclonal antibodies raised against an egg-white extract or the purified proteins. The necessity of these well-characterized proteins in studies on allergic reactions was shown by testing human sera in immunoblots of lysozyme, and by immunoblots of ovomucoid probing with antibodies against the proteins.

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[2] - Simonato B, de Lazzari F, Pasini G, Polato F, Giannattasio M, Gemignani C, et al. IgE binding to soluble and insoluble wheat flour proteins in atopic and non-atopic patients suffering from gastrointestinal symptoms after wheat ingestion. Clin Exp Allergy 2001;31:1771-1778

Background The involvement of IgE-mediated hypersensitivity reactions in the genesis of gastrointestinal symptoms after ingestion of foods containing wheat has been rarely reported. Objective : To detect IgE specifically binding to wheat proteins in the sera of atopic and non-atopic patients suffering from gastrointestinal symptoms after ingestion of wheat and to evaluate the reliability of skin prick test and CAP in the diagnosis of food allergy to wheat. Method s : The sera of patients (10 atopic and 10 non-atopic) previously diagnosed as suffering from irritable bowel syndrome and complaining of symptoms after wheat ingestion were analysed by immunoblotting for IgE binding to water/salt-soluble and insoluble wheat flour proteins. Result s : All the atopic patients and only one of the non-atopic patients were positive to wheat CAP. For the patients tested, skin prick test was positive for all the atopic patients and for only one of the non-atopic patients. However, immunoblotting experiments showed the presence of specific IgE to wheat proteins in all the patients. Ten out of 11 of the wheat CAP-positive patients had IgE binding to a soluble 16-kDa band, but the same band was recognized, in a slighter way, by only two out of nine of the wheat CAP-negative patients. Moreover, although almost all of the patients were negative in CAP testing with gluten, 19 out of 20 recognized protein bands belonging to the prolamin fraction. Conclusions : For the atopic patients the positivity to skin prick test and CAP to wheat was in accordance with the immunoblotting results and a food allergy to wheat could be diagnosed. In these patients a major allergen was a 16-kDa band corresponding to members of the cereal a-amylase/trypsin inhibitors protein family, the major allergens involved in baker's asthma. In the non-atopic patients the positive immunoblotting results contrasted with the responses of the allergologic tests, indicating that the allergenic wheat protein preparations currently used are of limited value in detecting specific IgE to wheat and that the fraction of irritable bowel syndrome (IBS) patients with food allergy may be larger than believed.

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[3] - Salvatori N, Reccardini F, Convento M, Purinan A, Colle R, De Carli S, et al. Asthma induced by inhalation of flour in adults with food allergy to wheat. Clin Exp Allergy 2008;38:1349-1356

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[4] - Pecquet C, Lauriere M, Huet S, Leynadier F. Is the application of cosmetics containing protein-derived products safe ? Contact Dermatitis 2002;46:123

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[5] - Piney D, Commun N, Kanny G. Les allergènes alimentaires à étiquetage obligatoire dans les 50 médicaments les plus vendus en pharmacie. Alim'Inter 2005;10:89-93

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[6] - de Boissieu D, Dupont C. Dermatite atopique de l'enfant et allergie au blé. Rev Fr Allergol Immunol Clin 2005;45:411-415

La fréquence de l'allergie au blé au cours de la dermatite atopique de l'enfant est évaluée entre 14 et 18 %. Elle a la particularité de se manifester souvent par des réactions retardées, avec des manifestations cutanées ou digestives. Les réactions immédiates sévères semblent relativement rares. La négativité des pricks tests et des IgE spécifiques au blé n'éliminent pas le diagnostic. Le test épicutané à la farine de blé semble le meilleur examen de dépistage, mais est peu spécifique chez le très jeune enfant. Le diagnostic doit être confirmé par un test de provocation qui doit être prolongé sur plusieurs jours en raison de la fréquence des réactions retardées.

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[7] - Saadoun-Cousin C, Paty E, Scheinmann P. Allergie au blé. Rev Fr Allergol Immunol Clin 2002;42:583-594

L'allergie alimentaire à la farine de blé est rare surtout chez l'enfant. Les manifestations cliniques varient de la dermatite atopique à l'urticaire et aux réactions anaphylactiques suite à l'ingestion de farine de blé ou de pain, ou induite par l'ingestion de blé et l'exercice physique. Parmi les céréales, les réactions croisées concernent surtout le blé, le seigle, l'orge et à moindre degré l'avoine. Les allergènes en cause sont nombreux, mais les gliadines (composants du gluten insolubles dans l'eau) semblent être un allergène majeur. La caractérisation de ces allergènes permettra une exploration plus fiable des allergies alimentaires à la farine de blé. L'identification des épitopes les plus allergéniques et la réduction de leur expression permettront de produire des blés hypoallergéniques.

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[8] - Sergeant P, Kanny G, Moneret-Vautrin DA. Régime d'éviction de la farine de blé. Alim'Inter 2006;11:257-258

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[9] - Day L, Augustin MA, Batey IL, Wrigley CW. Wheat-gluten uses and industry needs. Trends Food Sci Technol 2006;17:82-90

Gluten, the dough-forming protein of wheat flour, is the key to the unique ability of wheat to suit the production of leavened products. The past five decades have seen the rise of gluten as a commodity in its own right, through the large-scale industrial separation of wheat starch from gluten, plus the controlled drying of the gluten so as to retain its functional properties. The resulting Vital Dry Gluten is most widely used in bakery products. However, gluten (vital, de-vital or modified) is finding increasing use as a food ingredient to provide a range of functional properties at a more modest price than competitors such as milk and soy proteins.

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[10] - Battais F. Néo-allergénicité des isolats de blé: une allergie alimentaire en progression. Alim'Inter 2005;10:225

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[11] - Pecquet C, Laurière M. Hydrolysats de protéines du blé: nouveaux allergènes. Rev Fr Allergol Immunol Clin 2003;43:21-23

Le blé est cultivé pour la farine qu'il produit. Le gluten constitué des protéines de réserve est valorisé sous forme native ou modifiée. L'hydrolyse de ces protéines permet leur solubilisation et leur valorisation du fait des propriétés émulsifiantes et stabilisatrices des émulsions qui en résulte. Ces protéines de blé hydrolysées sont donc utilisées dans l'industrie alimentaire et cosmétique. Des réactions allergiques ont été décrites récemment : urticaire de contact aux produits cosmétiques en contenant et réaction d'urticaire ou choc anaphylactique lors de l'ingestion d'aliments. Ces nouveaux allergènes sont donc à connaître.

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[12] - Dutau G, Rancé F, Michaud P, Juchet A, Brémont F. Farines et allergie: les pièges à ne pas méconnaître. Rev Fr Allergol Immunol Clin 2002;42:289-298

Les farines sont des poudres plus ou moins fines, résultant de la mouture des grains de céréales et de certaines légumineuses. En dehors du cadre professionnel bien connu de l'asthme et des allergies du boulanger (rhinite, conjonctivite, eczéma), les farines (blé, maïs, lupin, millet, sarrasin, etc.) donnent lieu à des manifestations allergiques variées et de diagnostic parfois difficile. Des progrès ont été accomplis dans l'individualisation de syndromes nouveaux, en particulier l'anaphylaxie dépendante de l'exercice physique et de l'ingestion de farine de blé où les gliadines jouent un rôle de mieux en mieux connu. Les nombreux contaminants des farines sont également responsables de symptômes allergiques qu'il faut savoir rattacher à leur cause. La mode des « produits naturels » entraîne l'émergence d'allergies nouvelles, souvent sévères (millet, sarrasin, lupin). Le consommateur allergique doit être instruit de la possibilité de contaminations, prévues ou non déclarées, susceptibles de nuire gravement à sa santé (arachide, protéines du lait de vache, acariens, blattes, etc.). En conséquence, des efforts restent à faire tout au long de la chaîne de fabrication des aliments pour connaître avec précision les ingrédients utilisés. L'allergovigilance joue ici un rôle capital pour détecter les risques et informer le public.

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[13] - Paty E, Sheinmann P. Anaphylaxie à la farine de blé chez l'enfant. Rev Fr Allergol Immunol Clin 2008;48:287

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[14] - James JM, Sixbey JP, Helm RM, Bannon GA, Burks AW. Wheat alpha-amylase inhibitor: a second route of allergic sensitization. J Allergy Clin Immunol 1997;99:239-244

Low molecular weight allergens may be responsible for hypersensitivity reactions after the ingestion of wheat. OBJECTIVE: The purpose of this investigation was to identify relevant, low molecular weight allergens after the ingestion of wheat protein. METHODS: Serum samples were collected from seven children with wheat allergy and one adult with baker's asthma. Control serum samples were collected from wheat-tolerant patients. Wheat extracts were prepared and separated by sodium dodecylsulfate-polyacrylamide gel electrophoresis (SDS-PAGE) in 12.5% gels revealing numerous protein bands. IgE immunoblot analysis of crude wheat extracts identified multiple IgE-binding proteins. Wheat proteins were separated further with two-dimensional gel electrophoresis, which was followed by IgE immunoblotting investigations. RESULTS: Immunoblot analysis identified a 15 kd wheat protein that bound IgE from all five children with wheat allergy who were evaluated. No IgE binding to this wheat protein was demonstrated in any of the control subjects Samples representing the 15 kd wheat protein (isoelective point, 5.85) were selected. The N-terminal peptide sequence of this protein (residues 1 to 20) matched to a wheat alpha-amylase inhibitor. CONCLUSION: These data demonstrate that wheat alpha-amylase inhibitor is a relevant allergen in patients experiencing hypersensitivity reactions after the ingestion of wheat protein. This wheat protein, which has been implicated as an important allergen in patients with baker's asthma, represents a sensitizing allergen after both ingestion and inhalation.

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[15] - Daengsuwan T, Palosuo K, Phankingthongkum S, Visitsunthorn N, Jirapongsananuruk O, Alenius H, et al. IgE antibodies to omega-5 gliadin in children with wheat-induced anaphylaxis. Allergy 2005;60:506-509

Background: Wheat can cause severe immunoglobulin E (IgE)-mediated systemic reactions including anaphylaxis but knowledge on relevant wheat allergens at the molecular level is scanty. Methods: Seven children (aged from 6 months to 13 years) experiencing from 2 to 10 anaphylactic reactions in a year after eating food-containing wheat were examined. Purified omega-5 gliadin was used as an allergen in IgE enzyme-linked immunosorbent assay (ELISA) and in skin prick testing (SPT). Wheat CAP radioallergosorbent test (RAST) and SPT were also examined. Results: All seven anaphylactic children, but none of 15 control subjects had IgE antibodies to omega-5 gliadin in ELISA. Five of the six tested anaphylactic children showed positive SPT to omega-5 and crude gliadin, and all seven had positive wheat CAP RAST and SPT. One child was challenged with wheat, which caused anaphylaxis. After adherence to a wheat-free diet four children remained symptomless and three experienced one to two anaphylactic reactions. Conclusion: The present results show that wheat omega-5 gliadin is a major sensitizing allergen in children with wheat-induced anaphylaxis. They also suggest that omega-5 gliadin IgE ELISA could be used as a diagnostic test for this severe allergy.

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[16] - Codreanu F. L'activité du réseau Allergo-Vigilance: allergies alimentaires. Alim'Inter 2007;12:239-242

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[17] - Dosen AM, Ziegler JB, Kakayos A, Gold M. Australian National Surveillance of Anaphylaxis following food ingestion follow-up data from 2002-3. Allergy Clin Immunol Int 2005;17(Suppl. 1):65

Background Anaphylaxis is a life threatening, acute allergic reaction requiring prompt medical treatment.However, the incidence and mortality from anaphylaxis associated with food is not known.The Australian Paediatric Surveillance Unit study represents the first population based study of food anaphylaxis in Australian children. Aims The objectives of the study are to estimate the incidence of anaphylactic reactions to food in Australian children and their outcome; to describe clinical features of anaphylactic reactions to food and their management;to identify probable causative allergens;and to review current management of anaphylaxis in children. Method & Case Definition Anaphylaxis was defined as an immediate life-threatening, multisystem hypersensitivity response involving at least two of the following four systems: i. angioedoma, urticaria; ii.respiratory: airway obstruction; iii.gastrointestinal;iv.cardiovascular compromise. Cases have been notified if they were less than 15 years of age and had presented to a hospital or medical practitioner for medical treatment, with adrenaline being appropriate treatment. Children are excluded if their symptoms manifest as asthma or wheeze alone, or the allergic reaction is mild and requires no adrenaline treatment.Data was collected from questionnaires sent or emailed to paediatricians and adult allergists who notify cases via the APSU monthly surveillance.The prospective study commenced in July 2002 and ended in Dec 2003. Results There were 303 notifications, which is approx. 17 per month. The return rate on the questionnaires has been 175/303 (58%). Due to 13 invalid notifications there were 162 confirmed cases. Of the 162 cases, 44 (27%) were self limiting and did not need any active treatment. The incidence was 1.4 cases per 100.000. Male to female ratio was 1.6. Mean age is 4.5 years, range 3 months to 15 years. The commonest allergen reported was peanut at 51/175 (30%) then tree nuts at 35/175 (20%). Cashew was the main confirmed tree nut. Milk was the commonest allergen for children less than 2 years being 20% of cases. Five children were admitted to intensive care units and there were two reported deaths from these five. The first in a 15 year old girl known to have peanut allergy. This occurred after accidental exposure to peanut in salad dressing and in physical activity. The second in a 10 year old girl known to have nut allergy and was away from home.

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[18] - MacDougall CF, Cant AJ, Colver AF. How dangerous is food allergy in childhood ? The incidence of severe and fatal allergic reactions across the UK and Ireland. Arch Dis Child 2002;86:236-239

AIMS: To discover the incidence of fatal and severe allergic reactions to food in a large population of children. METHODS: A retrospective search for fatalities in children 0-15 years from 1990 to February 1998, primarily of death certification at offices of national statistics. A prospective survey of fatal and severe reactions from March 1998 to February 2000, primarily through the British Paediatric Surveillance Unit. MAIN OUTCOME MEASURES: were deaths and severe reactions. A case was deemed severe if one or more of the following criteria was met: cardiorespiratory arrest; need for inotropic support; fluid bolus >20 ml/kg; more than one dose of epinephrine; more than one dose of nebulised bronchodilator. A case was deemed near fatal if intubation was necessary. RESULTS: The UK under 16 population is 13 million. Over the past 10 years, eight children died (incidence of 0.006 deaths per 100 000 children 0-15 years per year). Milk caused four of the deaths. No child under 13 died from peanut allergy. Two children died despite receiving early epinephrine before admission to hospital; one child with a mild food allergic reaction died from epinephrine overdose. Over the past two years, there were six near fatal reactions (none caused by peanut) and 49 severe ones (10 caused by peanut), yielding incidences of 0.02 and 0.19 per 100 000 children 0-15 years per year respectively. Coexisting asthma is more strongly associated with a severe reaction than the severity of previous reactions. CONCLUSIONS: If 5% of the child population have food allergy, the risk that a food allergic child will die from a food allergic reaction is about 1 in 800 000 per year. The food allergic child with asthma may be at higher risk. Prescribing an epinephrine autoinjector requires a careful balance of advantages and disadvantages.

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[19] - de Boissieu D, Dupont C. Dermatite atopique de l'enfant et allergie au blé. Rev Fr Allergol Immunol Clin 2005;45:411-415

La fréquence de l'allergie au blé au cours de la dermatite atopique de l'enfant est évaluée entre 14 et 18 %. Elle a la particularité de se manifester souvent par des réactions retardées, avec des manifestations cutanées ou digestives. Les réactions immédiates sévères semblent relativement rares. La négativité des pricks tests et des IgE spécifiques au blé n'éliminent pas le diagnostic. Le test épicutané à la farine de blé semble le meilleur examen de dépistage, mais est peu spécifique chez le très jeune enfant. Le diagnostic doit être confirmé par un test de provocation qui doit être prolongé sur plusieurs jours en raison de la fréquence des réactions retardées.

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[20] - Blanco C, Carrillo T, Ortega N, Alvarez M, Dominguez C, Castillo R. Comparison of skin-prick test and specific serum IgE determination for the diagnosis of latex allergy. Clin Exp Allergy 1998;28:971-976

BACKGROUND: Latex IgE-mediated hypersensitivity has been recognized as an international health problem. However, there is poor information on the efficiency of the diagnostic methods available. OBJECTIVE: The purpose of this study was to specify the efficiency of several diagnostic methods for latex allergy. METHODS: We designed a prospective study involving 50 adult patients with latex allergy, as diagnosed by a suggestive clinical history and a positive skin-prick test (SPT) to a latex extract. One control group of 50 subjects paired for age, sex, total IgE levels and latex exposure, and another control group of 30 subjects with pollen allergy were used. A low-ammoniated natural-latex and several glove-latex extracts were elaborated. SPTs with these extracts, as well as with four different commercial-latex extracts were performed. Latex-specific serum IgE was determined by the CAP and the AlaSTAT methods. RESULTS: Diagnostic sensitivity was 98% for the natural-latex extract SPT, from 90% to 98% for the commercial-latex extract SPT, and from 64% to 96% for the glove-latex extract SPT. Diagnostic specificity of SPT was 100%, and no severe adverse reactions were observed during skin testing. With respect to the latex-specific serum IgE determinations, sensitivity was 86% for the CAP system and 84% for the AlaSTAT assay, and specificity was dependent on the population considered. CONCLUSION: SPT with natural latex extracts has shown a diagnostic efficiency close to 100%, significantly higher than that of latex-specific serum IgE determination.

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[21] - Roehr CC, Reibel S, Ziegert M, Sommerfeld C, Wahn U, Niggemann B. Atopy patch tests, together with determination of IgE levels, reduce the need for need for oral food challenges in children with atopic dermatitis. J Allergy Clin Immunol 2001;107:548-553

BACKGROUND: Atopic dermatitis is commonly associated with food allergy. In addition to skin prick tests (SPTs) and measurements of specific IgE levels, the atopy patch test (APT) has recently been introduced into the diagnostic procedure for food allergy . OBJECTIVE: Our aim was to evaluate whether a combination of allergologic tests could improve the prognostic value of the individual tests for positive food challenge results. We hypothesized that the combination of a positive APT result plus proof of specific IgE, a positive SPT result, or both would render double-blind, placebo-controlled, food challenges unnecessary . METHODS: One hundred seventy-three double-blind, placebo-controlled, food challenges were performed in 98 children (median age, 13 months) with atopic dermatitis. All children were subjected to SPTs, APTs, and determination of specific IgE. Sensitivity, specificity, and positive and negative predictive values were calculated . RESULTS: Ninety-five (55%) of 173 oral provocations were assessed as positive. For evaluating suspected cow's milk (CM) allergy, the APT was the best single predictive test (positive predictive value [PPV], 95%), and the combination of a positive APT result with evidence of specific IgE or an APT result together with a positive skin prick test response optimized the PPV to 100%. For hen's egg (HE) allergy, the APT was also the best single predictive test (PPV, 94%). The combination of 2 or more tests did not exceed the APT's predictive value. In both CM and HE challenges, the predictability of oral challenges depended on the level of specific IgE. For wheat allergy, the APT proved to be the most reliable test, and the PPV of 94% could not be improved by a combination with other allergologic tests . CONCLUSION: The combination of positive APT results and measurement of levels of specific IgE (CM, > or = 0.35 kU/L; HE, > or = 17.5 kU/L) makes double-blind, placebo-controlled, food challenges superfluous for suspected CM and HE allergy.

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[22] - Moneret-Vautrin DA, Kanny G, Perrier P, Denery-Papini S, Morisset M, Leduc V, et al. Etude prospective 1999-2002 de l'allergie alimentaire à la farine de blé chez l'enfant et chez l'adulte, comparée à la maladie coeliaque. Association de DR1 à l'allergie chez l'enfant. Alim'Inter 2003;8:2-8

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[23] - Sicherer SH, Morrow EH, Sampson HA. Dose-response in double-blind, placebo-controlled oral food challenges in children with atopic dermatitis. J Allergy Clin Immunol 2000;105:582-586

"BACKGROUND: Double-blind, placebo-controlled oral food challenges (DBPCFCs) are considered the ""gold standard"" for diagnosing food hypersensitivity, but the dose that elicits positive challenges, or determinants that may predict dose-response relationships, have not been reported . OBJECTIVE: Our purpose was to determine the quantity of food that elicits reactions during DBPCFCs and to evaluate parameters that may predict the provocative dose and severity of reaction . METHODS: We reviewed challenge data for all positive challenges to 6 common allergenic foods in children with atopic dermatitis evaluated for food allergy over a 13-year period. Challenge food was generally administered in 6 doses at 10- to 15-minute intervals beginning with 400 to 500 mg and completing with a total of 8 to 10 g of food. An open feeding of a larger portion followed negative challenges. At the physician's discretion, a lower starting dose was occasionally used (100 mg, 250 mg). Food-specific IgE antibody concentrations (radioallergosorbent test [RAST]) were determined on stored sera of 20% of the challenges selected randomly and 99.6% had prick skin tests (PSTs) performed to the challenged food . RESULTS: A total of 196 children (45% male; median age 5 y 9 mo; atopic dermatitis 98%, asthma 62%) had 513 positive challenges distributed as follows: egg 267, milk 117, soy 53, wheat 40, peanut 24, fish 12. The percentage of children reacting at the first dose (500 mg or less) was as follows: egg 49%, milk 55%, soy 28%, wheat 25%, peanut 26%, and fish 17%. Twenty-six milk challenges and 22 egg challenges were positive at a first dose of 250 mg; 3 milk challenges and 7 egg challenges were positive at a first dose of 100 mg. Eleven percent of the reactions that occurred on the first dose were severe. The percentage reacting after the final dose of the DBPCFC (or during open challenge) were egg 11%, milk 12%, soy 19%, wheat 12.5%, peanut 8.7%, and fish 25%. There was not a strong correlation between PST absolute wheal size or score (adjusted for histamine controls) and dose at reaction or severity of reaction (R(s) range -0.22 to 0.39 for particular foods). Serum concentration of food-specific IgE did not correlate well with the dose causing a reaction or with severity (R(s) range -0.40 to 0.55 for particular foods) . CONCLUSIONS: This food-allergic population may react to as little as 100 mg of food, possibly less, and the dose causing a reaction and the severity of reaction is not predicted by PST or RAST. Lower doses (100 mg or less) should be investigated for their appropriateness in initiating DBPCFCs."

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[24] - Niggemann B, Reibel S, Roehr CC, Felger D, Ziegert M, Sommerfeld C, et al. Predictors of positive food challenge outcome in non–IgE-mediated reactions to food in children with atopic dermatitis. J Allergy Clin Immunol 2001;108:1053-1058

Background: Atopic dermatitis is frequently associated with food allergy. In general, clinically manifested food allergy is regarded as IgE mediated. However, there are some children with food allergy for whom IgE hypersensitivity cannot be proven. OBJECTIVE: The aim was to evaluate the percentage of children with positive double-blind, placebo-controlled food challenge (DBPCFC) results but without any proof of IgE sensitization and to characterize this subgroup of children. METHODS: Two hundred eight DBPCFCs were performed in 139 children (median age, 13 months) with atopic dermatitis and suspected food-related clinical symptoms. All children were subjected to skin prick tests (SPTs), determination of specific IgE, and atopy patch tests. RESULTS: One hundred eleven (53%) of 208 oral food challenge results were assessed as positive. Positive challenge results were separated into 2 groups according to IgE positivity: negative SPT and negative specific IgE results in serum (group A, n = 12) and positive SPT, specific IgE, or both results in serum (group B, n = 99). The atopy patch test results; the distribution of early, late, or both clinical reactions; the age of the children; and the total IgE levels all showed no significant differences between the 2 groups. However, wheat challenge results were more often positive among the apparently nonˆIgE-sensitized children, and hen's egg challenge results were more often positive in the sensitized group (P < .05). CONCLUSION: Around 10% of positive DBPCFC results are not IgE mediated. Therefore not the proof of specific IgE but the suspicion of food-related symptoms should be the indication to perform oral food challenges, especially in the case of wheat. Otherwise, some children will not receive diagnoses for food allergy and be denied the benefits of a specific diet

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[25] - Heine RG, Pootong V, Bannister D, Hill DJ. Diagnostic Accuracy of Skin Prick Testing in Relation to Challenge Outcome in Children With Wheat Allergy. J Allergy Clin Immunol 2005;115(2 suppl.):S168

RATIONALE: Wheat is increasingly recognized as a major food allergen Data on the diagnostic accuracy of skin prick testing (SPT) in children with wheat allergy are limited METHODS: A retrospective review was performed of children with suspected wheat allergy who had undergone at least one wheat challenge SPT weal diameters (obtained within 6 months of the challenge) were correlated with challenge outcome, and positive predictive values (PPV) for each SPT weal diameter were calculated RESULTS: Of 186 open wheat challenges performed at the RCH between 1988-2003, 47 (25%) were positive, 113 (61%) negative, and 26 (14%) inconclusive. Forty-two children (median age at first challenge: 1.6 years; range 0.6 to 7.8; 29 male, 13 female) with challengeproven wheat allergy were identified. Of these, 32 (76%) developed immediate-onset reactions (including one patient with anaphylaxis), and 10 (24%) had late-onset reactions. All patients had evidence of IgE sensitization (>=3 mm) to at least one other food allergen (cow milk 74%, egg 79%, peanut 28%, other 36%). The mean SPT diameter in children with immediate-onset reactions was significantly greater than in those with late-onset reactions (4.7±3.38 vs 1.4±1.58 mm, p<0.001). SPT weal diameters in children with late-onset reactions were <4 mm. The PPV of a weal diameter to wheat >=3 mm was 41%, and 71% for a SPT >=6 mm. A SPT >=8 mm was 100% predictive and specific, but lacked sensitivity (19%) CONCLUSION: A SPT weal diameter >=8 mm was diagnostic of IgEmediated wheat allergy. The sensitivity of SPT was low, particularly in children with late-onset reactions

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[26] - Moneret-Vautrin DA, Kanny G, Perrier P, Denery-Papini S, Morisset M, Leduc V, et al. Etude prospective 1999-2002 de l'allergie alimentaire à la farine de blé chez l'enfant et chez l'adulte, comparée à la maladie coeliaque. Association de DR1 à l'allergie chez l'enfant. Alim'Inter 2003;8:2-8

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[27] - Battais F, Mothes T, Moneret-Vautrin DA, Pineau F, Kanny G, Popineau Y, et al. Identification of IgE-binding epitopes on gliadins for patients with food allergy to wheat. Allergy 2005;60:815-821

BACKGROUND: Food allergy to wheat induces different symptoms as atopic eczema/dermatitis syndrome (AEDS), urticaria and more severe reactions as wheat-dependent exercise-induced anaphylaxis (WDEIA). Different gliadin classes are involved in this allergy but IgE-binding epitopes are known only on omega5-gliadins and for WDEIA cases . OBJECTIVES: The aim of the study was to identify IgE-binding epitopes on several gliadin classes and for several patients with different symptoms and ages . METHODS: Eleven sera were analysed by pepscan with overlapping synthetic peptides . RESULTS: Sera from five patients with anaphylaxis, urticaria or WDEIA, displayed strong IgE-binding to sequential epitopes of the repetitive domains of alphabeta, gamma, omega2 or omega5-gliadins with two immunodominant epitopes on omega5-gliadin and a consensus motif of the type QQX1PX2QQ (X1 being L, F, S or I and X2 Q, E or G). One patient allergic to deamidated wheat proteins also had IgE to a repetitive peptide of gamma and omega2-gliadins of the type QPQQPFP. Sera from four patients with AEDS detected no linear epitopes on gliadins, despite the fact that they contained specific IgE to alpha, beta, gamma or omega-gliadins. One child with AEDS recognized cysteine-containing sequences in the nonrepetitive domains of alphabeta and gamma-gliadins . CONCLUSION: B epitopes in wheat allergy were different from B epitopes of coeliac disease. Differences exist in IgE-binding epitopes between patients with food allergy to wheat. IgE from those suffering from WDEIA, anaphylaxis and urticaria detected sequential epitopes in the repetitive domain of gliadins whereas IgE from AEDS patients probably recognized conformational epitopes.

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[28] - Sander I, Flagge A, Merget R, Halder TM, Meyer HE, Baur X. Identififcation of wheat flour allergens by means of 2-dimensional immunoblotting. J Allergy Clin Immunol 2001;107:907-913

BACKGROUND: Wheat flour proteins are allergens for 60% to 70% of bakers with workplace-related respiratory symptoms. OBJECTIVE: The aim of the study was to investigate the variability of IgE antibody patterns of wheat flour-sensitized bakers and to identify the most frequently recognized allergens. METHODS: Water/salt-soluble wheat flour proteins from the cultivar Bussard were separated by using 2-dimensional gel electrophoresis with immobilized pH gradients. IgE-reactive proteins were identified by means of immunoblotting with sera of 10 subjects with baker's asthma. Mass spectrometric fingerprinting was used to identify the proteins most frequently recognized by IgE. RESULTS: The IgE immunoblots obtained with 10 different sera exhibited a remarkable heterogeneity. Each patient showed an individual IgE-binding pattern with 4 to 50 different allergen spots. Altogether, more than 100 IgE-binding protein spots were detected. Nine of the predominant IgE-binding protein spots were identified by using mass spectrometric fingerprinting. The obtained masses matched 2 different isoforms of glycerinaldehyde-3-phosphate dehydrogenase from Hordeum vulgare, triosephosphate isomerase from H vulgare, and serpin, a serine proteinase inhibitor from Triticum aestivum. CONCLUSIONS: The results show a great interindividual variation of IgE-binding patterns of wheat flour proteins in baker's asthma. The clinical relevance of the identified 4 new allergens will be further investigated in the near future.

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[29] - Malandain H, Lavaud F. Allergénicité des protéines de défense végétale. Rev Fr Allergol Immunol Clin 2004;44:469-475

La synthèse de protéines de défense fait partie des réponses biochimiques que les plantes ont développées pour lutter contre leurs ennemis naturels et contre les stress environnementaux. De nombreuses protéines de défense végétale sont allergisantes : chitinases, protéines de transfert lipidique LTP, protéines Bet v 1-like. Cet article rappelle les principales familles de protéines de défense végétale, leur impact allergique et l'effet de certains procédés agricoles ou technoalimentaires sur l'allergénicité des aliments végétaux.

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[30] - Shewry PR, Halford NG. Cereal seed storage proteins: structures, properties and role in grain utilization. J Exp Bot 2002;53:947-958

Storage proteins account for about 50% of the total protein in mature cereal grains and have important impacts on their nutritional quality for humans and livestock and on their functional properties in food processing. Current knowledge of the structures and properties of the prolamin and globulin storage proteins of cereals and their mechanisms of synthesis, trafficking and deposition in the developing grain is briefly reviewed here. The role of the gluten proteins of wheat in determining the quality of the grain for breadmaking and how their amount and composition can be manipulated leading to changes in dough mixing properties is also discussed.

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[31] - Popineau Y, Denery-Papini S. Les protéines de réserve du grain de blé. in "Protéines végétales", Godon B., Lavoisier Technique et Documentation, Paris 1996, pp.121-170

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[32] - Mills ENC, Jenkins JA, Alcocer MJ, Shewry PR. Structural, biological, and evolutionary relationships of plant food allergens sensitizing via the gastrointestinal tract. Crit Rev Food Sci Nutr 2004;44:379-407

The recently completed genome sequence of the model plant species Arabidopsis has been estimated to encode over 25,000 proteins, which, on the basis of their function, can be classified into structural and metabolic (the vast majority of plant proteins), protective proteins, which defend a plant against invasion by pathogens or feeding by pests, and storage proteins, which proved a nutrient store to support germination in seeds. It is now clear that almost all plant food allergens are either protective or storage proteins. It is also becoming evident that those proteins that trigger the development of an allergic response through the gastrointestinal tract belong primarily to two large protein superfamilies: (1) The cereal prolamin superfamily, comprising three major groups of plant food allergens, the 2S albumins, lipid transfer proteins, and cereal alpha-amylase/trypsin inhibitors, which have related structures, and are stable to thermal processing and proteolysis. They include major allergens from Brazil nut, peanuts, fruits, such as peaches, and cereals, such as rice and wheat; (2) The cupin superfamily, comprising the major globulin storage proteins from a number of plant species. The globulins have been found to be allergens in plant foods, such as peanuts, soya bean, and walnut; (3) The cyteine protease C1 family, comprising the papain-like proteases from microbes, plants, and animals. This family contains two notable allergens that sensitize via the GI tract, namely actinidin from kiwi fruit and the soybean allergen, Gly m Bd 30k/P34. This study describes the properties, structures, and evolutionary relationships of these protein families, the allergens that belong to them, and discusses them in relation to the role protein structure may play in determining protein allergenicity.

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[33] - Denery-Papini S, Lauriere M, Branlard G, Morisset M, Pecquet C, Choudat D, et al. Influence of the Allelic Variants Encoded at the Gli-B1 Locus, Responsible for a Major Allergen of Wheat, on IgE Reactivity for Patients Suffering from Food Allergy to Wheat. J Agric Food Chem 2007;55:799-805

Wheat presents an important genetic diversity that could be useful to look for cultivars with reduced allergencity. omega5-Gliadins have been described as major allergens for wheat allergic patients suffering from wheat-dependent exercise-induced anaphylaxis (WDEIA) and some cases of chronic urticaria (U). Our objective was to study the influence of genetic variability at the Gli-B1 locus encoding for omega5-gliadins on the reactivity of IgE antibodies from these patients. We selected cultivars expressing 13 alleles at Gli-B1 including a wheat/rye translocation and studied the reactivity to gliadins of a rabbit antiserum specific for omega5-gliadins and of IgE from 10 patients. The antiserum and IgE from nine patients with WDEIA and U strongly detected omega5-gliadins expressed by most of the Gli-B1 alleles but showed no or faint responses to the gliadins and secalins extracted from the translocated wheat. The selection of genotypes lacking the Gli-B1 locus may reduce wheat allergenicity. Keywords: Wheat; food allergy; exercise induced anaphylaxis; omega5-gliadins; allelic variants.

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[34] - Laurière M, Pecquet C, Boulenc E, Bouchez-Mahiout I, Snégaroff J, Choudat D, et al. Genetic differences in omega-gliadins involved in two different immediate food hypersensitivities to wheat. Allergy 2007;62:890-896

BACKGROUND: Anti-gliadin IgE are expressed in patients with food allergy associated to skin immediate hypersensitivity to hydrolyzed wheat proteins (IHHWP). It is not known if they react with omega5-gliadins, the major allergens in wheat dependant exercise-induced food anaphylaxis (WDEIA), encoded on wheat chromosomes 1B. METHODS: Unmodified gliadins from 14 wheat varieties expressing most of the 1B omega-gliadin alleles, were immunoprobed after SDS-PAGE and blotting, with four sera from patients with IHHWP, and two with WDEIA. Gliadins reacting with IgE were visualized using chemiluminescence and identified according to their mobility and typical SDS-PAGE pattern. The resulting signal was also measured to compare their IgE reactivity. RESULTS: IHHWP and WDEIA sera exhibited distinct patterns of reactivity. IgE of patients with IHHWP reacted mainly with all omega-gliadins alleles and one gamma-gliadin encoded respectively on chromosomes 1D and 1B, but not with any omega5-gliadins alleles as for WDEIA. A few other reactive alleles of omega-gliadins were encoded on chromosomes 1A. Unassigned additional bands of the whole gliadin pattern were also reactive. The four patients with IHHWP exhibited almost the same pattern of reactivity. Main differences concerned band reactivity which modulated the overall reactivity of each wheat variety. CONCLUSIONS: The IgE epitopes involved in IHHWP and WDEIA are different. This suggests that the protein state and the route of exposure to very similar gluten structures, probably orientate the pattern of epitope reactivity and the wheat food allergy manifestations.

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[35] - Matsuo H, Morita E, Tatham AS, Morimoto K, Horikawa T, Osuna H, et al. Identification of the IgE-binding epitope in omega-5 gliadin, a major allergen in wheat-dependent exercise-induced anaphylaxis. J Biol Chem 2004;279:12135-12140

Wheat-dependent exercise-induced anaphylaxis (WDEIA) is a severe IgE-mediated allergic reaction provoked by the combination of wheat-ingestion with intensive physical exercise over the next few hours. Among wheat proteins, omega-5 gliadin, which is one of the components of fast omega-gliadin, has been reported as a major allergen in the anaphylaxis. In this study we detected IgE-binding epitopes within the primary sequence of omega-5 gliadin using arrays of overlapping peptides synthesized on derivatized cellulose membranes. Sera from 4 patients with WDEIA having specific IgE to the fast omega-gliadin were used to probe the membrane. Seven epitopes, QQIPQQQ, QQLPQQQ, QQFPQQQ, QQSPEQQ, QQSPQQQ, QQYPQQQ and PYPP, were detected within the primary sequence of omega-5 gliadin. By using sera of 15 patients, four of them, QQIPQQQ, QQFPQQQ, QQSPEQQ and QQSPQQQ, were found to be dominant epitopes. Mutational analysis of the QQIPQQQ and QQFPQQQ indicated that amino acids at position 1(Q), 4(P), 5(Q), 6(Q) and 7(Q) were critical for IgE-binding. These results will provide a useful tool for developing safer wheat products in addition to diagnostic and immunotherapy techniques for WDEIA.

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[36] - Morita E, Matsuo H, Mihara S, Morimoto K, Savage AW, Tatham AS. Fast omega-gliadin is a major allergen in wheat-dependent exercise-induced anaphylaxis. J Dermatol Sci 2003;33:99-104

BACKGROUND: Wheat-dependent exercise-induced anaphylaxis is an anaphylaxy induced by physical exercise after ingestion of wheat. An immediate-type hypersensitivity to water/salt-insoluble fraction of wheat proteins (gluten) has been considered to underlie in this disease. OBJECTIVE: The aim of the study is to determine the major allergen in Japanese patients with wheat-dependent exercise-induced anaphylaxis by using a panel of purified wheat gliadins and glutenins. METHODS: Water/salt-insoluble wheat proteins, alpha-gliadin, beta-gliadin, gamma-gliadin, fast omega-gliadin, slow omega-gliadin, high molecular weight glutenin and low molecular weight glutenin, were purified, and five patients with wheat-dependent exercise-induced anaphylaxis, whose diagnose had been determined by positive-challenge test, were evaluated for skin prick test, dot-blotting test and CAP-RAST inhibition test by using these purified wheat proteins. RESULTS: The fast omega-gliadin was the most potent allergen among these water/salt-insoluble proteins when evaluated by skin prick test and dot-blotting test. Fast and slow omega-gliadin, and gamma-gliadin caused dose-dependent inhibition of the serum IgE-binding to solid-phase gluten in the patients. The incubation with fast omega-gliadin of the patient's serum caused dose-dependent inhibition in the IgE-binding to gamma-gliadin as well as slow omega-gliadin, indicating a cross-reactivity of these proteins in IgE-binding. CONCLUSION: We concluded that fast omega-gliadin is a major allergen among these water/salt-insoluble proteins for wheat-dependent exercise-induced anaphylaxis in Japanese patients, and IgE against fast omega-gliadin cross-reacts to gamma-gliadin and slow omega-gliadin.

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[37] - Morita E, Kameyoshi Y, Mihara S, Hiragun T, Yamamoto S. gamma-Gliadin: a presumptive allergen causing wheat-dependent exercise-induced anaphylaxis. Br J Dermatol 2001;145:182-184

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[38] - Sotkovský P, Hubálek M, Hernychová L, Novák P, Havranová M, Setinová I, et al. Proteomic analysis of wheat proteins recognized by IgE antibodies of allergic patients. Proteomics 2008;8:1677-1691

Wheat belongs to six major food allergens inducing IgE-mediated hypersensitivity reaction manifesting as cutaneous, gastrointestinal, and respiratory symptoms. Although cereals are a staple food item in most diets, only a few wheat proteins causing hypersensitivity have been identified. To characterize wheat allergens, salt-soluble wheat extracts were separated by 1-DE and 2-DE and IgE-binding proteins were detected by immunoblotting using sera of patients with allergy to ingested wheat. Proteins, frequently recognized by IgE on 2-DE were analyzed by MALDI-TOF and QTOF and their spectrum was completed by 1-DE and LCQ(DECA) nLC-MS/MS IT technique. Using all three techniques we identified 19 potential wheat allergens such as alpha-amylase inhibitors, beta-amylase, profilin, serpin, beta-D-glucan exohydrolase, and 27K protein. Employing newly developed ELISA, levels of IgE Abs against Sulamit wheat extract and alpha-amylase inhibitors type 1 and 3 were quantified and shown to be significantly elevated in sera of allergic patients compared to those of healthy controls. The level of IgE Abs against alpha-amylase inhibitor type 3 was lower, slightly above the cut-off value in the majority of patients' sera. Our findings contribute to the identification of wheat allergens aimed to increase the specificity of serum IgE and cell activation diagnostic assays.

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[39] - Franken J, Stephan U, Meyer HE, Konig W. Identification of alpha-amylase inhibitor as a major allergen of wheat flour. Int Arch Allergy Immunol 1994;104:171-174

We isolated a major wheat flour allergen with a molecular weight of 15-kD The 15-kD allergen was purified from an extract of wheat flour by ammonium sulfate precipitation followed by gel filtration. Using the immunoblot technique, IgE, specifically directed towards the single isolated allergen, was detectable in 50% of the applied sera. We determined the N-terminal amino acid sequence of the allergen and identified it as an alpha-amylase inhibitor protein. Our data emphasize that low molecular weight wheat flour allergens play an important role in the pathogenesis of baker's asthma disease.

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[40] - James JM, Sixbey JP, Helm RM, Bannon GA, Burks AW. Wheat alpha-amylase inhibitor: a second route of allergic sensitization. J Allergy Clin Immunol 1997;99:239-244

Low molecular weight allergens may be responsible for hypersensitivity reactions after the ingestion of wheat. OBJECTIVE: The purpose of this investigation was to identify relevant, low molecular weight allergens after the ingestion of wheat protein. METHODS: Serum samples were collected from seven children with wheat allergy and one adult with baker's asthma. Control serum samples were collected from wheat-tolerant patients. Wheat extracts were prepared and separated by sodium dodecylsulfate-polyacrylamide gel electrophoresis (SDS-PAGE) in 12.5% gels revealing numerous protein bands. IgE immunoblot analysis of crude wheat extracts identified multiple IgE-binding proteins. Wheat proteins were separated further with two-dimensional gel electrophoresis, which was followed by IgE immunoblotting investigations. RESULTS: Immunoblot analysis identified a 15 kd wheat protein that bound IgE from all five children with wheat allergy who were evaluated. No IgE binding to this wheat protein was demonstrated in any of the control subjects Samples representing the 15 kd wheat protein (isoelective point, 5.85) were selected. The N-terminal peptide sequence of this protein (residues 1 to 20) matched to a wheat alpha-amylase inhibitor. CONCLUSION: These data demonstrate that wheat alpha-amylase inhibitor is a relevant allergen in patients experiencing hypersensitivity reactions after the ingestion of wheat protein. This wheat protein, which has been implicated as an important allergen in patients with baker's asthma, represents a sensitizing allergen after both ingestion and inhalation.

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[41] - Weiss W, Huber G, Engel KH, Pethran A, Dunn MJ, Gooley AA, et al. Identification and characterization of wheat grain albumin/globulin allergens. Electrophoresis 1997;18:826-833

Bakers' asthma, an immediate-type allergic response to the inhalation of cereal flours, is an important occupational disease among workers of the baking and milling industries, and the salt-soluble proteins of wheat and rye flour dust are considered the most relevant allergens. In order to identify the characterize the major IgE-binding proteins, the polypeptide composition of the albumin/globulin protein fraction obtained from different [wheat] cultivars was analysed by sodium dodecyl sulphate-polyacrylamide gel electrophoresis (SDS-PAGE), and high-resolution 2-dimensional polyacrylamide electrophoresis with immobilized pH gradients in the first dimension (IPG-Dalt), followed by immunoblotting with sera from asthmatic bakers. Relevant allergens were isolated by micropreparative IPG-Dalt, and blotting onto polyvinylidenedifluoride membranes and identified by amino acid composition analysis or N-terminal amino acid sequence analysis. SDS-PAGE, IPG-Dalt, and immunoblotting demonstrated that the sera of the bakers allergic to flour contained IgE antibodies which bound to numerous albumin/globulin polypeptides in the 70, 55, 35, 26-28 and 14-18 kDa areas. More detailed investigations using IPG-Dalt revealed cultivar-specific differences in IgE-binding. It was also demonstrated that the majority of the allergens were not single polypeptide spots, but consisted of up to 10 isoforms of similar molecular mass but different isoelectric points. Amino acid composition analysis and N-terminal amino acid sequence analysis, which were performed for 9 allergens located in the 14-18, 26-28 and 35 kDa areas, revealed homologies to amylase/protease inhibitors, acyl-CoA oxidase and fructose-bisphosphate-aldolase from wheat, barley, maize and rice, respectively

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[42] - Gomez L, Martin E, Hernandez D, Sanchez-Monge R, Barber D, del Pozo V, et al. Members of the alpha-amylase inhibitors family from wheat endosperm are major allergens associated with baker's asthma. FEBS Lett 1990;261:85-88

The major antigens or IgE binding components from wheat flour were identified. 35 sera from patients with bakers' asthma were used to analyse the reaction with wheat salt-soluble proteins. A 15 kD SDS-PAGE band which reacted with all sera tested was found. Purified members of the [alpha]-amylase inhibitor family, which are the main components of the 15 kDa band, were recognized by specific IgE when tested with a pool of reactive sera. Immunodetection after 2-dimensional electrophoretic fractionation of crude inhibitor preparations from [bread and durum] wheat endosperms also detected several inhibitor subunits as major low-mol.-wt. allergens

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[43] - Franken J, Stephan U, Meyer HE, Konig W. Identification of alpha-amylase inhibitor as a major allergen of wheat flour. Int Arch Allergy Immunol 1994;104:171-174

We isolated a major wheat flour allergen with a molecular weight of 15-kD The 15-kD allergen was purified from an extract of wheat flour by ammonium sulfate precipitation followed by gel filtration. Using the immunoblot technique, IgE, specifically directed towards the single isolated allergen, was detectable in 50% of the applied sera. We determined the N-terminal amino acid sequence of the allergen and identified it as an alpha-amylase inhibitor protein. Our data emphasize that low molecular weight wheat flour allergens play an important role in the pathogenesis of baker's asthma disease.

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[44] - Pastorello EA, Farioli L, Conti A, Pravettoni V, Bonomi S, Iametti S, et al. Wheat IgE-Mediated Food Allergy in European Patients: alpha-Amylase Inhibitors, Lipid Transfer Proteins and Low-Molecular-Weight Glutenins Allergenic Molecules Recognized by Double-Blind, Placebo-Controlled Food Challenge. Int Arch Allergy Immunol 2007;144:10-22

BACKGROUND: Three main problems hamper the identification of wheat food allergens: (1) lack of a standardized procedure for extracting all of the wheat protein fractions; (2) absence of double-blind, placebo-controlled food challenge studies that compare the allergenic profile of Osborne's three protein fractions in subjects with real wheat allergy, and (3) lack of data on the differences in IgE-binding capacity between raw and cooked wheat . METHODS: Sera of 16 wheat-challenge-positive patients and 6 patients with wheat anaphylaxis, recruited from Italy, Denmark and Switzerland, were used for sodium dodecyl sulfate-polyacrylamide gel electrophoresis/immunoblotting of the three Osborne's protein fractions (albumin/globulin, gliadins and glutenins) of raw and cooked wheat. Thermal sensitivity of wheat lipid transfer protein (LTP) was investigated by spectroscopic approaches. IgE cross-reactivity between wheat and grass pollen was studied by blot inhibition . RESULTS: The most important wheat allergens were the alpha-amylase/trypsin inhibitor subunits, which were present in all three protein fractions of raw and cooked wheat. Other important allergens were a 9-kDa LTP in the albumin/globulin fraction and several low-molecular-weight (LMW) glutenin subunits in the gluten fraction. All these allergens showed heat resistance and lack of cross-reactivity to grass pollen allergens. LTP was a major allergen only in Italian patients . CONCLUSIONS: The alpha-amylase inhibitor was confirmed to be the most important wheat allergen in food allergy and to play a role in wheat-dependent exercise-induced anaphylaxis, too. Other important allergens were LTP and the LMW glutenin subunits.

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[45] - James JM, Sixbey JP, Helm RM, Bannon GA, Burks AW. Wheat alpha-amylase inhibitor: a second route of allergic sensitization. J Allergy Clin Immunol 1997;99:239-244

Low molecular weight allergens may be responsible for hypersensitivity reactions after the ingestion of wheat. OBJECTIVE: The purpose of this investigation was to identify relevant, low molecular weight allergens after the ingestion of wheat protein. METHODS: Serum samples were collected from seven children with wheat allergy and one adult with baker's asthma. Control serum samples were collected from wheat-tolerant patients. Wheat extracts were prepared and separated by sodium dodecylsulfate-polyacrylamide gel electrophoresis (SDS-PAGE) in 12.5% gels revealing numerous protein bands. IgE immunoblot analysis of crude wheat extracts identified multiple IgE-binding proteins. Wheat proteins were separated further with two-dimensional gel electrophoresis, which was followed by IgE immunoblotting investigations. RESULTS: Immunoblot analysis identified a 15 kd wheat protein that bound IgE from all five children with wheat allergy who were evaluated. No IgE binding to this wheat protein was demonstrated in any of the control subjects Samples representing the 15 kd wheat protein (isoelective point, 5.85) were selected. The N-terminal peptide sequence of this protein (residues 1 to 20) matched to a wheat alpha-amylase inhibitor. CONCLUSION: These data demonstrate that wheat alpha-amylase inhibitor is a relevant allergen in patients experiencing hypersensitivity reactions after the ingestion of wheat protein. This wheat protein, which has been implicated as an important allergen in patients with baker's asthma, represents a sensitizing allergen after both ingestion and inhalation.

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[46] - Zapatero L, Martinez MI, Alonso E, Salcedo G, Sanchez-Monge R, Barber D, et al. Oral wheat flour anaphylaxis related to wheat alpha-amylase inhibitor subunits CM3 and CM16. Allergy 2003;58:956

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[47] - Battais F, Pineau F, Popineau Y, Aparicio C, Kanny G, Guérin L, et al. Food allergy to wheat: identification of IgE- and IgG-binding proteins with sequential extracts and purified proteins from wheat flour. Clin Exp Allergy 2003;33:962-970

BACKGROUND: Cereal-associated allergy is particularly considered a serious problem, because cereals are essential in our daily diet. Wheat proteins are classified into albumins, globulins and prolamins (insoluble gliadins and glutenins) . OBJECTIVES: Our objectives were to study the involvement in food allergy to wheat of these different protein types by using purified fractions and to identify those binding IgE and IgG antibodies . METHODS: Sera were obtained from 28 patients with food allergy to wheat. Albumins/globulins, gliadins and glutenins were obtained by sequential extraction based on differential solubility; alpha-, beta-, gamma- and omega-gliadins and low molecular weight (LMW) and high molecular weight (HMW) glutenin subunits were purified by chromatography. IgE binding to these extracts and fractions were analysed by radioallergosorbent test (RAST), and immunoblotting; IgG binding was detected by enzyme-linked immunosorbent assay (ELISA) . RESULTS: In RAST, 60% of sera were shown to have specific IgE antibodies against alpha-, beta-gliadins and LMW glutenin subunits, 55% to gamma-gliadins, 48% to omega-gliadins and 26% to HMW glutenins. Immunoblotting analysis confirmed results obtained in RAST concerning LMW and HMW glutenin subunits and showed that 67% of patients have IgE antibodies to the albumin/globulin fraction . CONCLUSION: Results obtained in the different tests showed common features and in agreement with other studies indicated the presence of numerous allergens in food allergy to wheat; alpha-, beta-, gamma- and omega-gliadins, LMW glutenin subunits and some water/salt-soluble proteins appeared as major IgE binding allergens, whereas HMW glutenins were only minor allergens. The same type of antigenic profile against gliadins and glutenins was observed with IgG antibodies. Important sequence or structural homologies between the various gliadins and LMW glutenin subunits could certainly explain similarity of IgE binding to these proteins.

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[48] - Simonato B, Pasini G, Giannattasio M, Peruffo AD, De Lazzari F, Curioni A. Food allergy to wheat products: the effect of bread baking and in vitro digestion on wheat allergenic proteins. A study with bread dough, crumb, and crust. J Agric Food Chem 2001;49:5668-5673

The effect of baking and digestion on the allergenicity of wheat flour proteins has been studied. Pooled sera of patients suffering from food allergy to wheat products were tested for IgE binding to the proteins of the wheat dough and of the bread crumb and crust, before and after being in vitro digested. During in vitro digestion, the IgE binding protein components of the unheated dough tended to disappear, whereas a permanence of IgE recognition was evident for both the bread crumb and crust. This indicates that the baking process increases the resistance of the potential allergens of the wheat flour to proteolytic digestion, allowing them to reach the gastrointestinal tract, where they can elicit the immunological response. Therefore, the effects of baking must be carefully considered in studying food allergies to wheat products.

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[49] - Armentia A, Sanchez-Monge R, Gomez L, Barber D, Salcedo G. In vivo allergenic activities of eleven purified members of a major allergen family from wheat and barley flour. Clin Exp Allergy 1993;23:410-415

Eleven purified members of the alpha-amylase/trypsin inhibitor family from wheat and barley that showed very different IgE-binding capacities when previously assayed in vitro, were used in double blind in vivo diagnostic tests to further evaluate their allergenic activity. These tests were carried out in 31 patients who showed allergic sensitization to wheat flour as verified by skin test, RAST and challenge test. The three members of the protein family with highest IgE binding in vitro (the glycosylated subunits of tetrameric alpha-amylase inhibitors CM16* from wheat and CMb* from barley, and the barley monomeric inhibitor BMAI-1) were found to be the strongest allergens as indicated by skin sensitivity in prick tests.

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[50] - Garcia-Casado G, Sanchez-Monge R, Chrispeels MJ, Armentia A, Salcedo G, Gomez L. Role of complex asparagine-linked glycans in the allergenicity of plant glycoproteins. Glycobiology 1996;6:471-477

Many plant proteins, particularly those found in foods and pollen, are known to act as sensitizing agents in humans upon repeated exposure. Among the cereal flour proteins involved in asthmatic reactions, those members of the alpha-amylase inhibitor family which are glycosylated, polypeptides, BMAI-1, BTAI-CMb*, and WTAI-CM16* are particularly reactive both in vivo and in vitro. We show here that these major glycoprotein allergens carry a single asparagine-linked complex glycan that contains both beta 1-->2 xylose and alpha 1-->3 fucose. Evidence is presented that the xylosyl residue and, to a lesser extent, the fucosyl residue are key IgE-binding epitopes and largely responsible for the allergenicity of these and unrelated proteins from plants and insects. Our results suggest that the involvement of xylose- and fucose-containing complex glycans in allergenic responses may have been underestimated previously these glycans provide a structural basis to help explain the cross-reactivities often observed between pollen, vegetable food, and insect allergens.

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[51] - Simonato B, de Lazzari F, Pasini G, Polato F, Giannattasio M, Gemignani C, et al. IgE binding to soluble and insoluble wheat flour proteins in atopic and non-atopic patients suffering from gastrointestinal symptoms after wheat ingestion. Clin Exp Allergy 2001;31:1771-1778

Background The involvement of IgE-mediated hypersensitivity reactions in the genesis of gastrointestinal symptoms after ingestion of foods containing wheat has been rarely reported. Objective : To detect IgE specifically binding to wheat proteins in the sera of atopic and non-atopic patients suffering from gastrointestinal symptoms after ingestion of wheat and to evaluate the reliability of skin prick test and CAP in the diagnosis of food allergy to wheat. Method s : The sera of patients (10 atopic and 10 non-atopic) previously diagnosed as suffering from irritable bowel syndrome and complaining of symptoms after wheat ingestion were analysed by immunoblotting for IgE binding to water/salt-soluble and insoluble wheat flour proteins. Result s : All the atopic patients and only one of the non-atopic patients were positive to wheat CAP. For the patients tested, skin prick test was positive for all the atopic patients and for only one of the non-atopic patients. However, immunoblotting experiments showed the presence of specific IgE to wheat proteins in all the patients. Ten out of 11 of the wheat CAP-positive patients had IgE binding to a soluble 16-kDa band, but the same band was recognized, in a slighter way, by only two out of nine of the wheat CAP-negative patients. Moreover, although almost all of the patients were negative in CAP testing with gluten, 19 out of 20 recognized protein bands belonging to the prolamin fraction. Conclusions : For the atopic patients the positivity to skin prick test and CAP to wheat was in accordance with the immunoblotting results and a food allergy to wheat could be diagnosed. In these patients a major allergen was a 16-kDa band corresponding to members of the cereal a-amylase/trypsin inhibitors protein family, the major allergens involved in baker's asthma. In the non-atopic patients the positive immunoblotting results contrasted with the responses of the allergologic tests, indicating that the allergenic wheat protein preparations currently used are of limited value in detecting specific IgE to wheat and that the fraction of irritable bowel syndrome (IBS) patients with food allergy may be larger than believed.

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[52] - Battais F, Douliez JP, Marion D, Kanny G, Popineau Y, Moneret-Vautrin DA, et al. Lipid transfer proteins of cereals in food allergy to wheat. EAACI 22th Congress, Paris, 7-11 June, 2003, Poster n°709, p.206

Background: Cereal grains have been recognised as the cause of adverse reactions in some individuals. Wheat grains contain Lipid Transfer Proteins (LTPs). LTPs are a well-known cause of allergic reactions to Rosaceae (apple, peach, apricot∑) but there are few studies on food allergy to cereal LTPs. Recently, a LTP has been identified as a major allergen in food-induced allergic reactions to maize. The aim of this study was to characterised the reactivity of IgE binding from a panel of sera from patients with food allergy to wheat against different LTPs from wheat (LTP1 and LTP2 with molecular masses of about 9 and 7 kDa respectively) barley and maize (LTP1s) and observed possible cross-reactions between these proteins. Methods: 23 sera from patients with food allergy to wheat and 2 controls were used in the study. Food allergy was established on the basis of IgE dependent sensitisation and by standardised oral challenge. The reactivity of IgE antibodies was analysed against purified LTPs by ELISA using a fluorogenic substrate. Results: Among the 23 sera, 13 were shown to have IgE antibodies to wheat LTP1 whereas 10 others were negative for this protein. Among wheat LTP1 positive sera, many different situations were observed : - one serum displayed a very strong response to the four LTPs tested - one serum reacted to the three LTP1s and not to the wheat LTP2 - some sera recognised strongly only two of the LTPs tested, either the wheat and barley LTP1s or the barley and maize LTP1s - three sera reacted only or more strongly to the two wheat LTPs and displayed responses of higher intensity for the LTP2 than for the LTP1 - one sera showed only a strong IgE response to the wheat LTP1. In addition, many sera among wheat LTP1 positive or negative sera and one serum control displayed low intensity responses to maize LTP1. Conclusion: This study showed a big diversity of IgE responses to cereal LTPs with numerous cross-reactions between the different LTPs tested. Sequence homologies between wheat LTP1 and barley LTP1 and to a lesser extent between these proteins and the maize LTP1 may explain some of the cross-reactions. However cross- reactions between LTP1 and LTP2 of wheat would be rather explained by homologies in the conformation of these proteins. It is interesting to observe that these reactions probably involved various conformational and linear epitopes.

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[53] - Pastorello EA, Farioli L, Conti A, Pravettoni V, Bonomi S, Iametti S, et al. Wheat IgE-Mediated Food Allergy in European Patients: alpha-Amylase Inhibitors, Lipid Transfer Proteins and Low-Molecular-Weight Glutenins Allergenic Molecules Recognized by Double-Blind, Placebo-Controlled Food Challenge. Int Arch Allergy Immunol 2007;144:10-22

BACKGROUND: Three main problems hamper the identification of wheat food allergens: (1) lack of a standardized procedure for extracting all of the wheat protein fractions; (2) absence of double-blind, placebo-controlled food challenge studies that compare the allergenic profile of Osborne's three protein fractions in subjects with real wheat allergy, and (3) lack of data on the differences in IgE-binding capacity between raw and cooked wheat . METHODS: Sera of 16 wheat-challenge-positive patients and 6 patients with wheat anaphylaxis, recruited from Italy, Denmark and Switzerland, were used for sodium dodecyl sulfate-polyacrylamide gel electrophoresis/immunoblotting of the three Osborne's protein fractions (albumin/globulin, gliadins and glutenins) of raw and cooked wheat. Thermal sensitivity of wheat lipid transfer protein (LTP) was investigated by spectroscopic approaches. IgE cross-reactivity between wheat and grass pollen was studied by blot inhibition . RESULTS: The most important wheat allergens were the alpha-amylase/trypsin inhibitor subunits, which were present in all three protein fractions of raw and cooked wheat. Other important allergens were a 9-kDa LTP in the albumin/globulin fraction and several low-molecular-weight (LMW) glutenin subunits in the gluten fraction. All these allergens showed heat resistance and lack of cross-reactivity to grass pollen allergens. LTP was a major allergen only in Italian patients . CONCLUSIONS: The alpha-amylase inhibitor was confirmed to be the most important wheat allergen in food allergy and to play a role in wheat-dependent exercise-induced anaphylaxis, too. Other important allergens were LTP and the LMW glutenin subunits.

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[54] - Palacin A, Quirce S, Armentia A, Fernández-Nieto M, Pacios LF, Asensio T, et al. Wheat lipid transfer protein is a major allergen associated with baker's asthma,. J Allergy Clin Immunol 2007;120:1132-1138

BACKGROUND: Baker's asthma is a frequent occupational allergic disorder mainly caused by inhalation of cereal flours. Lipid transfer proteins (LTPs) constitute a family of plant food panallergens, but their role as inhalant and wheat allergens is still unclear . OBJECTIVE: We sought to explore the involvement of wheat LTPs in baker's asthma caused by wheat flour sensitization . METHODS: Forty patients with occupational asthma caused by wheat flour inhalation were studied. Wheat LTP, Tri a 14, was purified by using a 2-step chromatographic protocol and characterized by N-terminal amino acid sequencing and 3-dimensional modeling. Its reactivity was confirmed by means of IgE immunodetection, ELISA and ELISA-inhibition assays, and skin prick tests . RESULTS: Specific IgE to Tri a 14 was found in 60% of 40 individual sera from patients with baker's asthma, and the purified allergen elicited positive skin prick test reactions in 62% of 24 of these patients. Tri a 14 and peach LTP, Pru p 3, showed a sequence identity of 45%, but the low cross-reactivity between both allergens detected in several individual sera reflected great differences in their 3-dimensional IgE-binding regions . CONCLUSIONS: Wheat LTP is a major inhalant allergen associated with baker's asthma caused by wheat flour sensitization. Poor cross-reactivity with its peach homolog was found in some patients. CLINICAL IMPLICATIONS: LTPs can be considered relevant inhalant allergens linked to respiratory disorders. LTP from wheat (Tri a 14) can be used as a helpful tool for the diagnosis of baker's asthma.

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[55] - Jégou S, Douliez JP, Mollé D, Boivin P, Marion D. Purification and structural characterization of LTP1 polypeptides from beer. J Agric Food Chem 2000;48:5023-5029

We report on the purification of lipid transfer proteins (LTP) from barley seeds and beer with the aim of investigating the chemical modifications that occur during the brewing process. In seeds, the well-known LTP of 9 kDa (LTP1) has been found together with a second form named LTPb that displays comparable amino acid composition but was not fully sequenced. These two forms have been recovered in beer with marked chemical modifications including disulfide bond reduction and rearrangement and especially glycation by Maillard reaction. The glycation is heterogeneous with variable amounts of hexose units bound to LTPs. Circular dichroism shows that glycated LTP1 having all their disulfide bridges reduced are totally unfolded. These results provide a first basis for understanding how barley LTPs become foam-promoting agents during the malting and brewing process.

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[56] - Pastorello EA, Farioli L, Pravettoni V, Ispano M, Scibola E, Trambaioli C, et al. The maize major allergen, which is responsible for food-induced allergic reactions, is a lipid transfer protein. J Allergy Clin Immunol 2000;106:744-751

BACKGROUND: Cereals are the most important nutritional component in the human diet. Food-induced allergic reactions to these substances therefore have serious implications, and exhaustive diagnosis is required. Such diagnosis is still difficult because of the incomplete knowledge about major cereal allergens. In particular, few food-induced allergic reactions to maize have been reported, and no information on the allergenic proteins is available. OBJECTIVE: Having observed several anaphylactic reactions to maize, we planned a study to identify maize major allergens and cross-reactivity with other cereals, as well as to peach because the majority of patients also reacted to Prunoideae fruits. METHODS: Twenty-two patients with systemic symptoms after maize ingestion and positive skin prick test responses and serum-specific IgE antibodies to maize were selected. The IgE-reactivity pattern was identified by SDS-PAGE and immunoblotting. The major allergen identified was then purified by HPLC and characterized by mass spectrometry, determination of the isoelectric point value, and N-terminal amino acid sequencing. RESULTS: Sera from 19 (86%) of the 22 patients recognized a 9-kd protein, thus confirming this as the maize major allergen. This protein had an isoelectric point of greater than 9, a molecular mass of 9047.0 d, and no glycosylation. Determination of its N-terminal sequence showed that it was a lipid transfer protein (LTP). By using immunoblotting-inhibition experiments, we demonstrated that the LTP cross-reacts completely with rice and peach LTPs but not with wheat or barley LTPs. N-terminal sequence of the 16-kd allergen (recognized by 36% of patients) showed it to be the maize inhibitor of trypsin. This protein cross-reacts completely with grass, wheat, barley, and rice trypsin inhibitors. CONCLUSION: The major allergen of maize is an LTP with a molecular weight of 9 kd that is highly homologous with the peach LTP, the major allergen of the Prunoideae subfamily.

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[57] - Battais F, Douliez JP, Marion D, Kanny G, Popineau Y, Moneret-Vautrin DA, et al. Lipid transfer proteins of cereals in food allergy to wheat. EAACI 22th Congress, Paris, 7-11 June, 2003, Poster n°709, p.206

Background: Cereal grains have been recognised as the cause of adverse reactions in some individuals. Wheat grains contain Lipid Transfer Proteins (LTPs). LTPs are a well-known cause of allergic reactions to Rosaceae (apple, peach, apricot∑) but there are few studies on food allergy to cereal LTPs. Recently, a LTP has been identified as a major allergen in food-induced allergic reactions to maize. The aim of this study was to characterised the reactivity of IgE binding from a panel of sera from patients with food allergy to wheat against different LTPs from wheat (LTP1 and LTP2 with molecular masses of about 9 and 7 kDa respectively) barley and maize (LTP1s) and observed possible cross-reactions between these proteins. Methods: 23 sera from patients with food allergy to wheat and 2 controls were used in the study. Food allergy was established on the basis of IgE dependent sensitisation and by standardised oral challenge. The reactivity of IgE antibodies was analysed against purified LTPs by ELISA using a fluorogenic substrate. Results: Among the 23 sera, 13 were shown to have IgE antibodies to wheat LTP1 whereas 10 others were negative for this protein. Among wheat LTP1 positive sera, many different situations were observed : - one serum displayed a very strong response to the four LTPs tested - one serum reacted to the three LTP1s and not to the wheat LTP2 - some sera recognised strongly only two of the LTPs tested, either the wheat and barley LTP1s or the barley and maize LTP1s - three sera reacted only or more strongly to the two wheat LTPs and displayed responses of higher intensity for the LTP2 than for the LTP1 - one sera showed only a strong IgE response to the wheat LTP1. In addition, many sera among wheat LTP1 positive or negative sera and one serum control displayed low intensity responses to maize LTP1. Conclusion: This study showed a big diversity of IgE responses to cereal LTPs with numerous cross-reactions between the different LTPs tested. Sequence homologies between wheat LTP1 and barley LTP1 and to a lesser extent between these proteins and the maize LTP1 may explain some of the cross-reactions. However cross- reactions between LTP1 and LTP2 of wheat would be rather explained by homologies in the conformation of these proteins. It is interesting to observe that these reactions probably involved various conformational and linear epitopes.

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[58] - Battais F, Courcoux P, Popineau Y, Kanny G, Moneret-Vautrin DA, Denery-Papini S. Food allergy to wheat: differences in IgE binding proteins as a function of age and symptoms. J Cereal Sci 2005;42:109-117

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[59] - Bodinier M, Brossard C, Triballeau S, Morisset M, Guérin-Marchand C, Pineau F, et al. Evaluation of an in vitro Mast Cell Degranulation Test in the Context of Food Allergy to Wheat. Int Arch Allergy Immunol 2008;146:307-320

BACKGROUND: Antigenic profiles obtained by ELISA with IgE from patients with wheat food allergy (WFA) established that major allergens are albumins/globulins (AG) for children suffering from atopic eczema/dermatitis syndrome (AEDS), omega5-gliadins for adults suffering from wheat-dependent exercise-induced anaphylaxis (WDEIA), anaphylaxis or urticaria and low-molecular-weight (LMW) glutenin subunits for patients with anaphylaxis. We aimed to characterize a new mast cell transfectant for its ability to degranulate with wheat proteins and patient sera and compare these results to those obtained by ELISA . METHODS: Thirty sera from patients with WFA were tested: 14 with AEDS (group 1) and 16 with WDEIA, anaphylaxis or urticaria (group 2). An IgE Fc receptor (FcepsilonRI) humanized rat RBL-2H3 line was established by transfection with cDNAs encoding alpha-, beta- and gamma-subunits for the human IgE receptor . RESULTS: A humanized RBL clone was selected for its capacity to express mRNA alpha-, beta- and gamma-subunits of FcepsilonRI, to bind allergen-specific human IgE and to degranulate. In group 1, sera induced enhanced degranulation with AG extract, but rarely reacted with gliadins and glutenins. In group 2, half of the sera showed degranulation with LMW glutenins whereas the AG fraction and lipid transfer proteins were rarely positive. omega5-Gliadins did not appear as a major allergen in degranulation assays, although functional allergen-specific IgE was measurable in appreciable amounts . CONCLUSION: Our data demonstrate that in wheat food allergen evaluation, correlation exists between mast cell degranulation and IgE measurements, depending on the type of allergen. Therefore, the biological activity of some allergen types may also be affected by other parameters.

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[60] - Battais F, Morisset M, Codreanu F, Kanny G, Moneret-Vautrin DA. Un nouvel allergène de la farine de blé: les protéines de transfert lipidique (LTP). Discussion sur l'implication clinique. Rev Fr Allergol Immunol Clin 2004;44:347

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[61] - De Gregorio M, Armentia A, Palacin A, Quirce S, Salcedo G, Diaz-Perales A. Wheat seed salt-soluble allergens from wheat-derived foodstuffs show lower IgE binding capacitiy than those from flour. Allergy 2008;63(suppl. 88):120

Salt-soluble proteins from wheat flour, such as a´ -amylase/trypsin inhibitors and lipid transfer proteins have been described as main allergens associated with both baker‚s asthma and food allergy. However, most of their identification studies have used raw flour as starting material, thus not considering potential changes in allergenic properties induced by the heat treatment and other industrial processing to produce wheatderived foodstuffs. Objetive: To investigate the IgE binding capacity of salt soluble proteins from wheat derived foods as well as their stability on simulated gastric digestion. Methods: Salts extracts from different commercial wheat-derived products (bread, pasta, etc) were obtained, and their IgE-binding properties investigated by IgE-immunodetection and ELISA assays. Chromatographic fractions enriched on IgE-binding proteins were obtained and characterized by N-terminal sequencing and fingerprinting. Simulated gastric digestion of these fractions was also accomplished. Results: The IgE-binding capacity of saltsoluble proteins from commercial breads and cooked pastas was reduced around 50% compared with that from raw flour, being the reduction less dramatic in non-cooked pasta and cookies. Most wheat-derived foodstuffs shown major IgE-binding components of 20 and 35 kDa, identified as avenin-like and globulins proteins. These proteins were hydrolyzed when subjected to simulated gastric fluid digestion. IgE binding bands of around 12-15 kDa, corresponding most probably to a´ -amylase inhibitor subunits were only detected in non cooked pasta. Tri a 14, the wheat LTP allergen, was located in some kind of breads by using anti-peach Pru p 3 antibodies but it was not recognized by sera from patients with food allergy. Conclusions: Processing of wheat flour to obtain wheat-derived foodstuffs seems to decrease strongly the IgE binding capacity of the major salt-soluble wheat proteins. Moreover, simulated gastric fluid digestion could further inactivate some heat-resistant potential allergens.

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[62] - Pastorello EA, Farioli L, Conti A, Pravettoni V, Bonomi S, Iametti S, et al. Wheat IgE-Mediated Food Allergy in European Patients: alpha-Amylase Inhibitors, Lipid Transfer Proteins and Low-Molecular-Weight Glutenins Allergenic Molecules Recognized by Double-Blind, Placebo-Controlled Food Challenge. Int Arch Allergy Immunol 2007;144:10-22

BACKGROUND: Three main problems hamper the identification of wheat food allergens: (1) lack of a standardized procedure for extracting all of the wheat protein fractions; (2) absence of double-blind, placebo-controlled food challenge studies that compare the allergenic profile of Osborne's three protein fractions in subjects with real wheat allergy, and (3) lack of data on the differences in IgE-binding capacity between raw and cooked wheat . METHODS: Sera of 16 wheat-challenge-positive patients and 6 patients with wheat anaphylaxis, recruited from Italy, Denmark and Switzerland, were used for sodium dodecyl sulfate-polyacrylamide gel electrophoresis/immunoblotting of the three Osborne's protein fractions (albumin/globulin, gliadins and glutenins) of raw and cooked wheat. Thermal sensitivity of wheat lipid transfer protein (LTP) was investigated by spectroscopic approaches. IgE cross-reactivity between wheat and grass pollen was studied by blot inhibition . RESULTS: The most important wheat allergens were the alpha-amylase/trypsin inhibitor subunits, which were present in all three protein fractions of raw and cooked wheat. Other important allergens were a 9-kDa LTP in the albumin/globulin fraction and several low-molecular-weight (LMW) glutenin subunits in the gluten fraction. All these allergens showed heat resistance and lack of cross-reactivity to grass pollen allergens. LTP was a major allergen only in Italian patients . CONCLUSIONS: The alpha-amylase inhibitor was confirmed to be the most important wheat allergen in food allergy and to play a role in wheat-dependent exercise-induced anaphylaxis, too. Other important allergens were LTP and the LMW glutenin subunits.

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[63] - Bodinier M, Legoux MA, Pineau F, Triballeau S, Segain JP, Brossard C, et al. Intestinal translocation capabilities of wheat allergens using the Caco-2 cell line. J Agric Food Chem 2007;55:4576-4583

Because intestinal absorption of food protein can trigger an allergic reaction, the effect of wheat proteins on intestinal epithelial cell permeability was evaluated and the abilities of these proteins in native or pepsin-hydrolyzed state to cross the epithelial cell monolayer were compared. Enterocytic monolayers were established by culturing Caco-2 cells, a model of enterocytes, on permeable supports that separate the apical and basal compartments. Proteins were added into the apical compartment, and the transepithelial resistance (TER) was measured; proteins that crossed the cell monolayer were detected in the basal medium by ELISA. Wheat proteins did not alter the cell monolayer. TER and Caco-2 cell viability were conserved, and the passage of dextran was prevented. Native and pepsin-hydrolyzed forms of omega5-gliadin and lipid transfer proteins were detected in the basal medium. The results suggest that these two major allergens in food allergy to wheat were able to cross the cell monolayer by the transcellular route.

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[64] - Palacin A, Quirce S, Armentia A, Fernández-Nieto M, Pacios LF, Asensio T, et al. Wheat lipid transfer protein is a major allergen associated with baker's asthma,. J Allergy Clin Immunol 2007;120:1132-1138

BACKGROUND: Baker's asthma is a frequent occupational allergic disorder mainly caused by inhalation of cereal flours. Lipid transfer proteins (LTPs) constitute a family of plant food panallergens, but their role as inhalant and wheat allergens is still unclear . OBJECTIVE: We sought to explore the involvement of wheat LTPs in baker's asthma caused by wheat flour sensitization . METHODS: Forty patients with occupational asthma caused by wheat flour inhalation were studied. Wheat LTP, Tri a 14, was purified by using a 2-step chromatographic protocol and characterized by N-terminal amino acid sequencing and 3-dimensional modeling. Its reactivity was confirmed by means of IgE immunodetection, ELISA and ELISA-inhibition assays, and skin prick tests . RESULTS: Specific IgE to Tri a 14 was found in 60% of 40 individual sera from patients with baker's asthma, and the purified allergen elicited positive skin prick test reactions in 62% of 24 of these patients. Tri a 14 and peach LTP, Pru p 3, showed a sequence identity of 45%, but the low cross-reactivity between both allergens detected in several individual sera reflected great differences in their 3-dimensional IgE-binding regions . CONCLUSIONS: Wheat LTP is a major inhalant allergen associated with baker's asthma caused by wheat flour sensitization. Poor cross-reactivity with its peach homolog was found in some patients. CLINICAL IMPLICATIONS: LTPs can be considered relevant inhalant allergens linked to respiratory disorders. LTP from wheat (Tri a 14) can be used as a helpful tool for the diagnosis of baker's asthma.

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[65] - Pastorello EA, Farioli L, Conti A, Pravettoni V, Bonomi S, Iametti S, et al. Wheat IgE-Mediated Food Allergy in European Patients: alpha-Amylase Inhibitors, Lipid Transfer Proteins and Low-Molecular-Weight Glutenins Allergenic Molecules Recognized by Double-Blind, Placebo-Controlled Food Challenge. Int Arch Allergy Immunol 2007;144:10-22

BACKGROUND: Three main problems hamper the identification of wheat food allergens: (1) lack of a standardized procedure for extracting all of the wheat protein fractions; (2) absence of double-blind, placebo-controlled food challenge studies that compare the allergenic profile of Osborne's three protein fractions in subjects with real wheat allergy, and (3) lack of data on the differences in IgE-binding capacity between raw and cooked wheat . METHODS: Sera of 16 wheat-challenge-positive patients and 6 patients with wheat anaphylaxis, recruited from Italy, Denmark and Switzerland, were used for sodium dodecyl sulfate-polyacrylamide gel electrophoresis/immunoblotting of the three Osborne's protein fractions (albumin/globulin, gliadins and glutenins) of raw and cooked wheat. Thermal sensitivity of wheat lipid transfer protein (LTP) was investigated by spectroscopic approaches. IgE cross-reactivity between wheat and grass pollen was studied by blot inhibition . RESULTS: The most important wheat allergens were the alpha-amylase/trypsin inhibitor subunits, which were present in all three protein fractions of raw and cooked wheat. Other important allergens were a 9-kDa LTP in the albumin/globulin fraction and several low-molecular-weight (LMW) glutenin subunits in the gluten fraction. All these allergens showed heat resistance and lack of cross-reactivity to grass pollen allergens. LTP was a major allergen only in Italian patients . CONCLUSIONS: The alpha-amylase inhibitor was confirmed to be the most important wheat allergen in food allergy and to play a role in wheat-dependent exercise-induced anaphylaxis, too. Other important allergens were LTP and the LMW glutenin subunits.

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[66] - Sander I, Flagge A, Merget R, Halder TM, Meyer HE, Baur X. Identififcation of wheat flour allergens by means of 2-dimensional immunoblotting. J Allergy Clin Immunol 2001;107:907-913

BACKGROUND: Wheat flour proteins are allergens for 60% to 70% of bakers with workplace-related respiratory symptoms. OBJECTIVE: The aim of the study was to investigate the variability of IgE antibody patterns of wheat flour-sensitized bakers and to identify the most frequently recognized allergens. METHODS: Water/salt-soluble wheat flour proteins from the cultivar Bussard were separated by using 2-dimensional gel electrophoresis with immobilized pH gradients. IgE-reactive proteins were identified by means of immunoblotting with sera of 10 subjects with baker's asthma. Mass spectrometric fingerprinting was used to identify the proteins most frequently recognized by IgE. RESULTS: The IgE immunoblots obtained with 10 different sera exhibited a remarkable heterogeneity. Each patient showed an individual IgE-binding pattern with 4 to 50 different allergen spots. Altogether, more than 100 IgE-binding protein spots were detected. Nine of the predominant IgE-binding protein spots were identified by using mass spectrometric fingerprinting. The obtained masses matched 2 different isoforms of glycerinaldehyde-3-phosphate dehydrogenase from Hordeum vulgare, triosephosphate isomerase from H vulgare, and serpin, a serine proteinase inhibitor from Triticum aestivum. CONCLUSIONS: The results show a great interindividual variation of IgE-binding patterns of wheat flour proteins in baker's asthma. The clinical relevance of the identified 4 new allergens will be further investigated in the near future.

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[67] - Posch A, Weiss W, Wheeler CH, Dunn MJ, Gorg A. Sequence analysis of wheat grain allergens separated by two-dimensional electrophoresis with immobilized pH gradients. Electrophoresis 1995;16:1115-1119

Micropreparative two-dimensional (2-D) gel electrophoresis with immobilized pH gradients (4-8) in the first dimension (IPG-DALT) was optimized for the separation of salt-soluble wheat grain proteins, associated with bakers' asthma disease. The resolved polypeptides were electroblotted onto a polyvinylidene difluoride (PVDF) membrane and incubated with the pooled sera from four asthmatic bakers. Bound IgE was demonstrated by alkaline phosphatase conjugated anti-human IgE. Major IgE binding was detected in the 27 kDa, 37 kDa and, to a lesser extent, in the 14-18 kDa area of the 2-D immunoblots, respectively. Since the main purpose of our study was to determine the N-terminal amino acid sequences of the major wheat grain allergens, N-terminal sequencing was performed for six out of a total of eleven major allergens located in the 27 kDa area, for one out of two 37 kDa allergens, and for two out of four 14-18 kDa allergens. Our results revealed that two of the 27 kDa polypeptides are clearly related to several Acyl-CoA oxidase variants of barley and rice, whereas no significant homologies were found for the remaining four 27 kDa allergens analyzed. The N-terminus of the 37 kDa allergen appeared to be blocked so that no sequence information was obtained, while the two 14-18 kDa allergens analyzed were identified as members of the wheat alpha-amylase-inhibitor family.

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[68] - Weiss W, Huber G, Engel KH, Pethran A, Dunn MJ, Gooley AA, et al. Identification and characterization of wheat grain albumin/globulin allergens. Electrophoresis 1997;18:826-833

Bakers' asthma, an immediate-type allergic response to the inhalation of cereal flours, is an important occupational disease among workers of the baking and milling industries, and the salt-soluble proteins of wheat and rye flour dust are considered the most relevant allergens. In order to identify the characterize the major IgE-binding proteins, the polypeptide composition of the albumin/globulin protein fraction obtained from different [wheat] cultivars was analysed by sodium dodecyl sulphate-polyacrylamide gel electrophoresis (SDS-PAGE), and high-resolution 2-dimensional polyacrylamide electrophoresis with immobilized pH gradients in the first dimension (IPG-Dalt), followed by immunoblotting with sera from asthmatic bakers. Relevant allergens were isolated by micropreparative IPG-Dalt, and blotting onto polyvinylidenedifluoride membranes and identified by amino acid composition analysis or N-terminal amino acid sequence analysis. SDS-PAGE, IPG-Dalt, and immunoblotting demonstrated that the sera of the bakers allergic to flour contained IgE antibodies which bound to numerous albumin/globulin polypeptides in the 70, 55, 35, 26-28 and 14-18 kDa areas. More detailed investigations using IPG-Dalt revealed cultivar-specific differences in IgE-binding. It was also demonstrated that the majority of the allergens were not single polypeptide spots, but consisted of up to 10 isoforms of similar molecular mass but different isoelectric points. Amino acid composition analysis and N-terminal amino acid sequence analysis, which were performed for 9 allergens located in the 14-18, 26-28 and 35 kDa areas, revealed homologies to amylase/protease inhibitors, acyl-CoA oxidase and fructose-bisphosphate-aldolase from wheat, barley, maize and rice, respectively

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[69] - Carrillo T, de Castro FR, Cuevas M, Caminero J, Cabrera P. Allergy to limpet. Allergy 1991;46:515-519

Allergy to mollusk has rarely been described. The limpet, belonging to Phylum mollusca, is one of the most frequent mollusks in the Canary Islands, as in all warm maritime regions. We report two cases of atopic patients who developed anaphylactic reactions after ingestion of this mollusk. Type I hypersensitivity to limpet antigens was demonstrated by means of immediate skin test reactivity, specific IgE determination by RAST, and histamine release test to cooked limpet extract. The controls did not react to any of these tests. Allergic activity was only found with a cooked limpet extract; this suggests that the offending antigen/s may have been released by cooking this food.

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[70] - Yamashita H, Nanba Y, Onishi M, Kimoto M, Hiemori M, Tsuji H. Identification of a wheat allergen, Tri a Bd 36K, as a peroxidase. Biosci Biotechnol Biochem 2002;66:2487-2490

A 36-kDa allergen, Tri a Bd 36K, was purified from wheat albumin and characterized. The protein was similar to barley peroxidase BP-1 both in its amino acid sequence and peroxidase activity. The enzyme seemed to contain L-fucose and D-mannose and the glycan moiety reacted with IgE antibodies in a patient's serum.

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[71] - Pastorello EA, Farioli L, Conti A, Pravettoni V, Bonomi S, Iametti S, et al. Wheat IgE-Mediated Food Allergy in European Patients: alpha-Amylase Inhibitors, Lipid Transfer Proteins and Low-Molecular-Weight Glutenins Allergenic Molecules Recognized by Double-Blind, Placebo-Controlled Food Challenge. Int Arch Allergy Immunol 2007;144:10-22

BACKGROUND: Three main problems hamper the identification of wheat food allergens: (1) lack of a standardized procedure for extracting all of the wheat protein fractions; (2) absence of double-blind, placebo-controlled food challenge studies that compare the allergenic profile of Osborne's three protein fractions in subjects with real wheat allergy, and (3) lack of data on the differences in IgE-binding capacity between raw and cooked wheat . METHODS: Sera of 16 wheat-challenge-positive patients and 6 patients with wheat anaphylaxis, recruited from Italy, Denmark and Switzerland, were used for sodium dodecyl sulfate-polyacrylamide gel electrophoresis/immunoblotting of the three Osborne's protein fractions (albumin/globulin, gliadins and glutenins) of raw and cooked wheat. Thermal sensitivity of wheat lipid transfer protein (LTP) was investigated by spectroscopic approaches. IgE cross-reactivity between wheat and grass pollen was studied by blot inhibition . RESULTS: The most important wheat allergens were the alpha-amylase/trypsin inhibitor subunits, which were present in all three protein fractions of raw and cooked wheat. Other important allergens were a 9-kDa LTP in the albumin/globulin fraction and several low-molecular-weight (LMW) glutenin subunits in the gluten fraction. All these allergens showed heat resistance and lack of cross-reactivity to grass pollen allergens. LTP was a major allergen only in Italian patients . CONCLUSIONS: The alpha-amylase inhibitor was confirmed to be the most important wheat allergen in food allergy and to play a role in wheat-dependent exercise-induced anaphylaxis, too. Other important allergens were LTP and the LMW glutenin subunits.

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[72] - Sotkovský P, Hubálek M, Hernychová L, Novák P, Havranová M, Setinová I, et al. Proteomic analysis of wheat proteins recognized by IgE antibodies of allergic patients. Proteomics 2008;8:1677-1691

Wheat belongs to six major food allergens inducing IgE-mediated hypersensitivity reaction manifesting as cutaneous, gastrointestinal, and respiratory symptoms. Although cereals are a staple food item in most diets, only a few wheat proteins causing hypersensitivity have been identified. To characterize wheat allergens, salt-soluble wheat extracts were separated by 1-DE and 2-DE and IgE-binding proteins were detected by immunoblotting using sera of patients with allergy to ingested wheat. Proteins, frequently recognized by IgE on 2-DE were analyzed by MALDI-TOF and QTOF and their spectrum was completed by 1-DE and LCQ(DECA) nLC-MS/MS IT technique. Using all three techniques we identified 19 potential wheat allergens such as alpha-amylase inhibitors, beta-amylase, profilin, serpin, beta-D-glucan exohydrolase, and 27K protein. Employing newly developed ELISA, levels of IgE Abs against Sulamit wheat extract and alpha-amylase inhibitors type 1 and 3 were quantified and shown to be significantly elevated in sera of allergic patients compared to those of healthy controls. The level of IgE Abs against alpha-amylase inhibitor type 3 was lower, slightly above the cut-off value in the majority of patients' sera. Our findings contribute to the identification of wheat allergens aimed to increase the specificity of serum IgE and cell activation diagnostic assays.

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[73] - Weichel M, Vergoossen NJ, Bonomi S, Scibilia J, Ortolani C, Ballmer-Weber BK, et al. Screening the allergenic repertoires of wheat and maize with sera from double-blind, placebo-controlled food challenge positive patients. Allergy 2006;61:128-135

BACKGROUND: Food allergy to wheat and maize is an increasing factor of deterioration of life quality, especially childhood and can, in rare cases, even induce anaphylaxis. Although omega-5 gliadin from wheat and maize lipid transfer protein have been characterized as major cereal allergens on the molecular level, the list of food allergens is far to be complete . METHODS: To identify the IgE-binding repertoires of wheat and maize we screened respective cDNA libraries displayed on phage surface with sera from patients with a confirmed food allergy. The study included six patients with a positive double-blind, placebo-controlled food challenge (DBPCFC) to wheat, nine patients with a positive DBPCFC to maize, and six patients with anaphylactic reactions after ingestion of wheat . RESULTS: The enriched sequences encoding IgE-binding proteins showed heterogeneous repertoires for both, wheat and maize. The selected wheat repertoire yielded 12, the maize repertoire 11 open reading frames. Among these we identified allergens belonging to already characterized allergens families, such as gliadin, profilin and beta-expansin. Besides, we found novel proteins with high cross-reactive potential, such as thioredoxins, as well as sequences that had so far not been related to cereal allergy at all. The IgE-binding capacity of some selected proteins was evaluated in vitro and cross-reactivity was demonstrated by competition ELISA . CONCLUSION: With regard to the heterogeneity of the characterized sequences as well as to the biochemical nature of the new allergens detected we conclude that wheat and maize-related food allergy is more complex than so far anticipated.

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[74] - Diaz-Perales A, Collada C, Blanco C, Sanchez-Monge R, Carillo T, Aragoncillo C, et al. Cross-reactions in the latex-fruit syndrome: a relevant role of chitinases but not of complex asparagine-linked glycans. J Allergy Clin Immunol 1999;104:681-687

BACKGROUND: Cross-reactions between latex and plant foods (mainly fruits) have been widely reported. Although the cross-reactive components have not been well identified, class I chitinases seem to be the most credible candidates in chestnut, avocado, and banana . OBJECTIVE: We sought to evaluate the potential role of chitinases and complex glycans as cross-reactive determinants linked to latex-food allergy . METHODS: Extracts from 20 different plant foods and from latex were obtained. These preparations were immunodetected with anticomplex glycans and antichitinase sera raised in rabbits, as well as with sera from patients with latex-fruit allergy and sera from patients allergic to latex without food allergy. Immunoblot inhibition assays were carried out by using a purified class I chitinase from avocado or latex extract as inhibitors . RESULTS: Reactive proteins of approximately 30 to 45 kd (putative class I chitinases) were recognized by both specific polyclonal antibodies to chitinases and sera from patients with latex-fruit allergy in chestnut, cherimoya, passion fruit, kiwi, papaya, mango, tomato, and flour wheat extracts. Prs a 1, the major allergen and class I chitinase from avocado, and the latex extract strongly or fully inhibited IgE binding by these components when tested in immunoblot inhibition assays. Additional bands of 16 to 20 kd, 23 to 28 kd, and 50 to 70 kd were detected by the antichitinase serum but not with the patients' pooled sera. The putative 30- to 45-kd chitinases present in different food extracts did not react with a pool of sera from subjects allergic to latex but not to fruit. Very different immunodetection patterns were produced with the anticomplex glycan serum and the sera from allergic patients . CONCLUSIONS: Putative class I chitinases seem to be relevant cross-reactive components in foods associated with the latex-fruit syndrome, but do not play a specific role in allergy to latex but not to fruit. Cross-reactive carbohydrate determinants are not important structures in the context of latex-fruit cross-sensitization.

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[75] - Watanabe J, Tanabe S, Sonoyama K, Kuroda M, Watanabe M. IgE-reactive 60 kDa glycoprotein occurring in wheat flour. Biosci Biotechnol Biochem 2001;65:2102-2105

A new IgE-reactive glycoprotein with a molecular size of 60 kDa was isolated from wheat flour. The N-terminal amino acid sequence of the protein was LDPDESEXVTRYFRIR. The 8th amino acid residue would have been Asn to which the peroxidase-type glycochain was attached. The IgE-binding activity of the glycoprotein was rendered negligible by the enzymatic treatment applied for hypoallergenic flour production.

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[76] - Jensen-Jarolim E, Schmid B, Bernier F, Berna A, Kinaciyan T, Focke M, et al. Allergologic exploration of germins and germin-like proteins, a new class of plant allergens. Allergy 2002;57:805-810

BACKGROUND: Germins and the related germin-like proteins (GLPs) are glycoproteins expressed in many plants in response to biotic and abiotic stress. To test the potential impact of germins and GLPs, recombinant germin from Triticum aestivum (tGermin) and GLPs from Arabidopsis thaliana (tGLP), both produced in transformed tobacco plants, were used . METHODS: Sera from 82 patients with type I allergy to birch, grass or mugwort pollen and/or wheat were tested in immunoblot for IgE binding to tGermin and tGLP, and the IgE reactivity after chemical and enzymatic deglycosylation was analysed. The biological activity of tGermin and tGLP was determined in a histamine release assay and in skin prick testing (SPT) . RESULTS: In an immunoblotting assay, 24 out of 82 tested sera (29.26%) from allergic patients showed IgE-binding to tGermin, and 18 of these sera (21.95%) displayed also IgE-binding to tGLP. The deglycosylation experiments indicated that glycan moieties contribute significantly to the IgE-binding of tGermin and tGLP. Both tGermins and tGLP induced specifically histamine release in an in vitro assay as well as in SPT . CONCLUSION: Our in vitro and in vivo findings demonstrate that germin and GLPs are capable to bind IgE most likely via carbohydrate determinants, and represent allergenic molecules.

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[77] - Sotkovský P, Hubálek M, Hernychová L, Novák P, Havranová M, Setinová I, et al. Proteomic analysis of wheat proteins recognized by IgE antibodies of allergic patients. Proteomics 2008;8:1677-1691

Wheat belongs to six major food allergens inducing IgE-mediated hypersensitivity reaction manifesting as cutaneous, gastrointestinal, and respiratory symptoms. Although cereals are a staple food item in most diets, only a few wheat proteins causing hypersensitivity have been identified. To characterize wheat allergens, salt-soluble wheat extracts were separated by 1-DE and 2-DE and IgE-binding proteins were detected by immunoblotting using sera of patients with allergy to ingested wheat. Proteins, frequently recognized by IgE on 2-DE were analyzed by MALDI-TOF and QTOF and their spectrum was completed by 1-DE and LCQ(DECA) nLC-MS/MS IT technique. Using all three techniques we identified 19 potential wheat allergens such as alpha-amylase inhibitors, beta-amylase, profilin, serpin, beta-D-glucan exohydrolase, and 27K protein. Employing newly developed ELISA, levels of IgE Abs against Sulamit wheat extract and alpha-amylase inhibitors type 1 and 3 were quantified and shown to be significantly elevated in sera of allergic patients compared to those of healthy controls. The level of IgE Abs against alpha-amylase inhibitor type 3 was lower, slightly above the cut-off value in the majority of patients' sera. Our findings contribute to the identification of wheat allergens aimed to increase the specificity of serum IgE and cell activation diagnostic assays.

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[78] - Constantin C, Quirce S, Grote M, Touraev A, Swoboda I, Stoecklinger A, et al. Molecular and Immunological Characterization of a Wheat Serine Proteinase Inhibitor as a Novel Allergen in Baker's Asthma. J Immunol 2008;180:7451-7460

Abstract IgE-mediated sensitization to wheat flour belongs to the most frequent causes of occupational asthma. A cDNA library from wheat seeds was constructed and screened with serum IgE from baker's asthma patients. One IgE-reactive phage clone contained a full-length cDNA coding for an allergen with a molecular mass of 9.9 kDa and an isoelectric point of 6. According to sequence analysis it represents a member of the potato inhibitor I family, a group of serine proteinase inhibitors, and thus is the first allergen belonging to the group 6 pathogenesis-related proteins. The recombinant wheat seed proteinase inhibitor was expressed in Escherichia coli and purified to homogeneity. According to circular dichroism analysis, it represented a soluble and folded protein with high thermal stability containing mainly beta-sheets, random coils, and an alpha-helical element. The recombinant allergen showed allergenic activity in basophil histamine release assays and reacted specifically with IgE from 3 of 22 baker's asthma pati ents, but not with IgE from grass pollen allergic patients or patients suffering from food allergy to wheat. Allergen-specific Abs were raised to localize the allergen by immunogold electron microscopy in the starchy endosperm and the aleuron layer. The allergen is mainly expressed in mature wheat seeds and, despite an approximately 50% sequence identity, showed no relevant cross-reactivity with allergens from other plant-derived food sources such as maize, rice, beans, or potatoes. Recombinant wheat serine proteinase inhibitor, when used in combination with other specific allergens, may be useful for the diagnosis and therapy of IgE-mediated baker's asthma

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[79] - Akagawa M, Handoyo T, Ishii T, Kumazawa S, Morita N, Suyama K. Proteomic Analysis of Wheat Flour Allergens. J Agric Food Chem 2007;55:6863-6870

Wheat can cause severe IgE-mediated systematic reactions, but knowledge on relevant wheat allergens at the molecular level is scanty. The aim of the present study was to achieve a more detailed and comprehensive characterization of the wheat allergens involved in food allergy to wheat using proteomic strategies, referred to as "allergenomics". Whole flour proteins were separated by two-dimensional gel electrophoresis with isoelectric focusing and lithium dodecyl sulfate-polyacrylamide gel electrophoresis. Then, IgE-binding proteins were detected by immunoblotting with sera of patients with a food allergy to wheat. After tryptic digestion, the peptides of IgE-binding proteins were analyzed by matrix-assisted laser desorption ionization tandem time-of-flight mass spectrometry. In this study, we identified four previously reported wheat allergens or their sequentially homologous proteins [serpin, alpha-amylase inhibitor, gamma-gliadin, and low molecular weight (LMW) glutenin] by a database search. As a result of the high resolution of two-dimensional gel electrophoresis, nine subunits of LMW glutenins were identified as the most predominant IgE-binding antigens. The two-dimensional allergen map can be beneficial in many ways. It could be used, for example, for precise diagnosis of wheat-allergic patients and assessment of wheat allergens in food. Additionally, we compared allergenomics to conventional biochemical methods and evaluated the usefulness of a proteomic strategy for identifying putative allergens to wheat allergy

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[80] - Sander I, Flagge A, Merget R, Halder TM, Meyer HE, Baur X. Identififcation of wheat flour allergens by means of 2-dimensional immunoblotting. J Allergy Clin Immunol 2001;107:907-913

BACKGROUND: Wheat flour proteins are allergens for 60% to 70% of bakers with workplace-related respiratory symptoms. OBJECTIVE: The aim of the study was to investigate the variability of IgE antibody patterns of wheat flour-sensitized bakers and to identify the most frequently recognized allergens. METHODS: Water/salt-soluble wheat flour proteins from the cultivar Bussard were separated by using 2-dimensional gel electrophoresis with immobilized pH gradients. IgE-reactive proteins were identified by means of immunoblotting with sera of 10 subjects with baker's asthma. Mass spectrometric fingerprinting was used to identify the proteins most frequently recognized by IgE. RESULTS: The IgE immunoblots obtained with 10 different sera exhibited a remarkable heterogeneity. Each patient showed an individual IgE-binding pattern with 4 to 50 different allergen spots. Altogether, more than 100 IgE-binding protein spots were detected. Nine of the predominant IgE-binding protein spots were identified by using mass spectrometric fingerprinting. The obtained masses matched 2 different isoforms of glycerinaldehyde-3-phosphate dehydrogenase from Hordeum vulgare, triosephosphate isomerase from H vulgare, and serpin, a serine proteinase inhibitor from Triticum aestivum. CONCLUSIONS: The results show a great interindividual variation of IgE-binding patterns of wheat flour proteins in baker's asthma. The clinical relevance of the identified 4 new allergens will be further investigated in the near future.

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[81] - Pastorello EA, Farioli L, Conti A, Pravettoni V, Bonomi S, Iametti S, et al. Wheat IgE-Mediated Food Allergy in European Patients: alpha-Amylase Inhibitors, Lipid Transfer Proteins and Low-Molecular-Weight Glutenins Allergenic Molecules Recognized by Double-Blind, Placebo-Controlled Food Challenge. Int Arch Allergy Immunol 2007;144:10-22

BACKGROUND: Three main problems hamper the identification of wheat food allergens: (1) lack of a standardized procedure for extracting all of the wheat protein fractions; (2) absence of double-blind, placebo-controlled food challenge studies that compare the allergenic profile of Osborne's three protein fractions in subjects with real wheat allergy, and (3) lack of data on the differences in IgE-binding capacity between raw and cooked wheat . METHODS: Sera of 16 wheat-challenge-positive patients and 6 patients with wheat anaphylaxis, recruited from Italy, Denmark and Switzerland, were used for sodium dodecyl sulfate-polyacrylamide gel electrophoresis/immunoblotting of the three Osborne's protein fractions (albumin/globulin, gliadins and glutenins) of raw and cooked wheat. Thermal sensitivity of wheat lipid transfer protein (LTP) was investigated by spectroscopic approaches. IgE cross-reactivity between wheat and grass pollen was studied by blot inhibition . RESULTS: The most important wheat allergens were the alpha-amylase/trypsin inhibitor subunits, which were present in all three protein fractions of raw and cooked wheat. Other important allergens were a 9-kDa LTP in the albumin/globulin fraction and several low-molecular-weight (LMW) glutenin subunits in the gluten fraction. All these allergens showed heat resistance and lack of cross-reactivity to grass pollen allergens. LTP was a major allergen only in Italian patients . CONCLUSIONS: The alpha-amylase inhibitor was confirmed to be the most important wheat allergen in food allergy and to play a role in wheat-dependent exercise-induced anaphylaxis, too. Other important allergens were LTP and the LMW glutenin subunits.

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[82] - Sotkovský P, Hubálek M, Hernychová L, Novák P, Havranová M, Setinová I, et al. Proteomic analysis of wheat proteins recognized by IgE antibodies of allergic patients. Proteomics 2008;8:1677-1691

Wheat belongs to six major food allergens inducing IgE-mediated hypersensitivity reaction manifesting as cutaneous, gastrointestinal, and respiratory symptoms. Although cereals are a staple food item in most diets, only a few wheat proteins causing hypersensitivity have been identified. To characterize wheat allergens, salt-soluble wheat extracts were separated by 1-DE and 2-DE and IgE-binding proteins were detected by immunoblotting using sera of patients with allergy to ingested wheat. Proteins, frequently recognized by IgE on 2-DE were analyzed by MALDI-TOF and QTOF and their spectrum was completed by 1-DE and LCQ(DECA) nLC-MS/MS IT technique. Using all three techniques we identified 19 potential wheat allergens such as alpha-amylase inhibitors, beta-amylase, profilin, serpin, beta-D-glucan exohydrolase, and 27K protein. Employing newly developed ELISA, levels of IgE Abs against Sulamit wheat extract and alpha-amylase inhibitors type 1 and 3 were quantified and shown to be significantly elevated in sera of allergic patients compared to those of healthy controls. The level of IgE Abs against alpha-amylase inhibitor type 3 was lower, slightly above the cut-off value in the majority of patients' sera. Our findings contribute to the identification of wheat allergens aimed to increase the specificity of serum IgE and cell activation diagnostic assays.

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[83] - Pastorello EA, Farioli L, Conti A, Pravettoni V, Bonomi S, Iametti S, et al. Wheat IgE-Mediated Food Allergy in European Patients: alpha-Amylase Inhibitors, Lipid Transfer Proteins and Low-Molecular-Weight Glutenins Allergenic Molecules Recognized by Double-Blind, Placebo-Controlled Food Challenge. Int Arch Allergy Immunol 2007;144:10-22

BACKGROUND: Three main problems hamper the identification of wheat food allergens: (1) lack of a standardized procedure for extracting all of the wheat protein fractions; (2) absence of double-blind, placebo-controlled food challenge studies that compare the allergenic profile of Osborne's three protein fractions in subjects with real wheat allergy, and (3) lack of data on the differences in IgE-binding capacity between raw and cooked wheat . METHODS: Sera of 16 wheat-challenge-positive patients and 6 patients with wheat anaphylaxis, recruited from Italy, Denmark and Switzerland, were used for sodium dodecyl sulfate-polyacrylamide gel electrophoresis/immunoblotting of the three Osborne's protein fractions (albumin/globulin, gliadins and glutenins) of raw and cooked wheat. Thermal sensitivity of wheat lipid transfer protein (LTP) was investigated by spectroscopic approaches. IgE cross-reactivity between wheat and grass pollen was studied by blot inhibition . RESULTS: The most important wheat allergens were the alpha-amylase/trypsin inhibitor subunits, which were present in all three protein fractions of raw and cooked wheat. Other important allergens were a 9-kDa LTP in the albumin/globulin fraction and several low-molecular-weight (LMW) glutenin subunits in the gluten fraction. All these allergens showed heat resistance and lack of cross-reactivity to grass pollen allergens. LTP was a major allergen only in Italian patients . CONCLUSIONS: The alpha-amylase inhibitor was confirmed to be the most important wheat allergen in food allergy and to play a role in wheat-dependent exercise-induced anaphylaxis, too. Other important allergens were LTP and the LMW glutenin subunits.

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[84] - Weichel M, Vergoossen NJ, Bonomi S, Scibilia J, Ortolani C, Ballmer-Weber BK, et al. Screening the allergenic repertoires of wheat and maize with sera from double-blind, placebo-controlled food challenge positive patients. Allergy 2006;61:128-135

BACKGROUND: Food allergy to wheat and maize is an increasing factor of deterioration of life quality, especially childhood and can, in rare cases, even induce anaphylaxis. Although omega-5 gliadin from wheat and maize lipid transfer protein have been characterized as major cereal allergens on the molecular level, the list of food allergens is far to be complete . METHODS: To identify the IgE-binding repertoires of wheat and maize we screened respective cDNA libraries displayed on phage surface with sera from patients with a confirmed food allergy. The study included six patients with a positive double-blind, placebo-controlled food challenge (DBPCFC) to wheat, nine patients with a positive DBPCFC to maize, and six patients with anaphylactic reactions after ingestion of wheat . RESULTS: The enriched sequences encoding IgE-binding proteins showed heterogeneous repertoires for both, wheat and maize. The selected wheat repertoire yielded 12, the maize repertoire 11 open reading frames. Among these we identified allergens belonging to already characterized allergens families, such as gliadin, profilin and beta-expansin. Besides, we found novel proteins with high cross-reactive potential, such as thioredoxins, as well as sequences that had so far not been related to cereal allergy at all. The IgE-binding capacity of some selected proteins was evaluated in vitro and cross-reactivity was demonstrated by competition ELISA . CONCLUSION: With regard to the heterogeneity of the characterized sequences as well as to the biochemical nature of the new allergens detected we conclude that wheat and maize-related food allergy is more complex than so far anticipated.

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[85] - Weichel M, Glaser AG, Ballmer-Weber BK, Schmid-Grendelmeier P, Crameri R. Wheat and maize thioredoxins: A novel cross-reactive cereal allergen family related to baker's asthma. J Allergy Clin Immunol 2006;117:676-681

BACKGROUND: Baker's asthma is a serious problem for a significant proportion of workers in bakeries, confectionaries, and the food industry. Although several wheat allergens related to baker's asthma have been described, standardized reagents for a reliable diagnosis are not yet available . OBJECTIVE: To clone novel wheat allergens related to baker's asthma and investigate the cross-reactive potential of their maize and human homologues . METHODS: A wheat cDNA phage display library was screened with sera from bakers with occupational asthma for IgE-binding structures. Homologous sequences from maize and human thioredoxins were amplified from corresponding cDNA libraries . RESULTS: Within the enriched wheat cDNA repertoire we identified, among others, the sequence encoding wheat thioredoxin-hB (Triticum aestivum allergen 25 [Tri a 25]). The recombinant protein displayed enzymatic activity, and we observed a sensitization rate of 47% among bakers with occupational asthma and of 35% among patients with grass pollen allergy, but without a clinical history of cereal allergy. Furthermore, the previously characterized maize thioredoxin-h1 (Zea mays allergen 25 [Zea m 25]), sharing 74% identity with Tri a 25, exhibited distinct IgE cross-reactivity with its wheat homologue. Two bakers also showed sensitization to human thioredoxin, which shares 29% identity with Tri a 25. In a comparative study, we included recombinant alpha-amylase inhibitor 0.19, showing a sensitization rate of 65% in individuals with baker's asthma . CONCLUSION: Thioredoxins represent a novel family of cross-reactive allergens that might contribute to the symptoms of baker's asthma and might in addition be related to grass pollen allergy, as indicated by the reactivity of grass pollen allergic patients to cereal thioredoxins. CLINICAL IMPLICATIONS: The recombinant cereal thioredoxins will, together with the already reported wheat allergens, contribute to a more reliable diagnosis of baker's asthma and, perhaps, become a tool for the development of component-resolved immunotherapy.

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[86] - Karisola P, Alenius H, Turjanmaa K, Reunala T, Kalkkinen N, Palosuo T, et al. Hevein-like Domain IV in Wheat Germ Agglutinin (WGA) is Responsible for the Majority of IgE Cross-reactivity between WGA and Hevein (Hev b 6.02). AAAAI 59th Annual Meeting, Denver, 7-12 March, 2003, Poster n°1034

RATIONALE: Crystal structure of wheat germ agglutinin (WGA) reveals four covalently connected homologous domains resembling hevein (Hev b6.02), a major latex allergen. IgE from up to half of latex-allergic patients recognize WGA in ELISA or immunoblotting. The detailed molecular basis of this alleged cross-reactivity was examined. METHODS: The 4 hevein-like domains of WGA were separately produced in insect cell system and their immunogenicity was tested with sera from hevein-allergic patients. RESULTS: In ELISA no detectable binding of IgE was seen to hevein-like domains I and II of WGA. In contrast, domain IV and, to a some extent, domain III bound IgE from hevein-allergic patients. CONCLUSIONS: Majority of the IgE-binding ability of WGA appears to reside in its hevein-like domain IV. To assess the clinical significance of this cross-reactivity in vivo studies are needed.

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[87] - Weichel M, Vergoossen NJ, Bonomi S, Scibilia J, Ortolani C, Ballmer-Weber BK, et al. Screening the allergenic repertoires of wheat and maize with sera from double-blind, placebo-controlled food challenge positive patients. Allergy 2006;61:128-135

BACKGROUND: Food allergy to wheat and maize is an increasing factor of deterioration of life quality, especially childhood and can, in rare cases, even induce anaphylaxis. Although omega-5 gliadin from wheat and maize lipid transfer protein have been characterized as major cereal allergens on the molecular level, the list of food allergens is far to be complete . METHODS: To identify the IgE-binding repertoires of wheat and maize we screened respective cDNA libraries displayed on phage surface with sera from patients with a confirmed food allergy. The study included six patients with a positive double-blind, placebo-controlled food challenge (DBPCFC) to wheat, nine patients with a positive DBPCFC to maize, and six patients with anaphylactic reactions after ingestion of wheat . RESULTS: The enriched sequences encoding IgE-binding proteins showed heterogeneous repertoires for both, wheat and maize. The selected wheat repertoire yielded 12, the maize repertoire 11 open reading frames. Among these we identified allergens belonging to already characterized allergens families, such as gliadin, profilin and beta-expansin. Besides, we found novel proteins with high cross-reactive potential, such as thioredoxins, as well as sequences that had so far not been related to cereal allergy at all. The IgE-binding capacity of some selected proteins was evaluated in vitro and cross-reactivity was demonstrated by competition ELISA . CONCLUSION: With regard to the heterogeneity of the characterized sequences as well as to the biochemical nature of the new allergens detected we conclude that wheat and maize-related food allergy is more complex than so far anticipated.

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[88] - Tanabe S, Watanabe J, Oyama K, Fukushi E, Kawabata J, Arai S, et al. Isolation and characterization of a novel polysaccharide as a possible allergen occurring in wheat flour. Biosci Biotechnol Biochem 2000;64:1675-1680

Purification and identification of a non-protein allergen in wheat flour are reported. A polysaccharide, with a mol. wt. of 5.0 x 104 was identified as a potential wheat allergen from a water soluble fraction of flour. Purification of the polysaccharide was via affinity chromatography and gel filtration. The isolated polysaccharide was found to be a possible wheat allergen, as it bound specifically to IgE antibodies in sera of patients allergic to a water-soluble fraction of flour. Chemically, the sugar moiety of the polysaccharide consisted of D-glucose and D-mannose with [beta]-1,4-linkages in a molar ratio of 4.4:1. Since this mannoglucan is thought to be stable in the body, it is suggested that the polysaccharide may act as a remaining allergen to cause a long-lasting allergic reaction to wheat flour.

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[89] - Houba R, Doekes G, Heederik D. Occupational respiratory allergy in bakery workers: a review of the literature. Am J Ind Med 1998;34:529-546

Baker's asthma has long been recognized as a serious disease among workers in the bakery industry and the number of cases with baker's asthma is steadily increasing. This paper presents a review of the available literature on baker's allergy with a special focus on the allergens involved, the epidemiologic research and issues on exposure assessment, evidence of exposure-response-relationships, and possible prevention strategies. A large number of potential allergens have been identified and are described here. At present little is known about the incidence of baker's allergy. On the other hand, a large number of cross-sectional studies have been performed, showing that sensitization and work-related symptoms are common among bakery workers. Only atopy and exposure level have consistently been reported as determinants of this occupational disease. Age, gender, and smoking habits do not seem to be associated with sensitization or work-related respiratory symptoms. Recently, immunochemical methods have been developed to measure specific allergens in the bakery industry, which have been used to unravel the role of allergen exposure in the development of baker's asthma. Clear exposure-response-relationships have been found. The implications of these recent findings for prevention strategies and standard setting are discussed.

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[90] - Brant A. Baker's asthma. Curr Opin Allergy Clin Immunol 2007;7:152-155

PURPOSE OF REVIEW: Baker's asthma is one of the leading causes of occupational asthma and this review describes recent developments in the field. RECENT FINDINGS: The location of bakery production has undergone change and, subsequently, so has the location of baker's asthma. Innovations in the baking industry have also led to new, potentially allergenic, ingredients. A new family of cereal allergens has been identified, including wheat thioredoxin hb (Tri a25). New enzymes are being added to bread that may have allergic potential. The relationship of specific sensitization and baker's asthma has been confirmed in further studies. Measuring specific sensitization to bakery allergens is an essential part of making the diagnosis but there is a lack of standardization of allergen tests. Advancements are being made in the measurement of airborne allergens through the Measurement of Occupational Allergen Exposure project and the development of novel measurement techniques. This will enable better exposure-response relationships and more accurate risk assessment. SUMMARY: Progress is being made to better identify bakery allergens and measure exposures accurately. Changes in the location of bread production and new allergens mean that the distribution and determinants of baker's asthma are changing.

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[91] - Hinojosa M. Occupational asthma in bakers: role of enzymes. Alergol Immunol Clin 2000;15:32-33

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[92] - Fourgaut G, Popin E, Kopferschmitt MC, Newinger G, Pauli G. L'asthme à la farine : étude clinique de 27 cas (nécessité d'un algorithme décisionnel). Rev Fr Allergol Immunol Clin 2002;42:633-639

Objectifs. ˆ À partir de l'étude de patients retenus comme ayant un asthme professionnel dans le milieu de la boulangerie par des cliniciens experts, les auteurs précisent l'apport des différents examens complémentaires. Matériel et méthodes. ˆ Les dossiers de 27 sujets diagnostiqués entre 1983 et 1999, présentant un asthme professionnel de gravité variable, sont étudiés. Le bilan allergologique complet a été effectué avec recherche des sensibilités à la farine par tests cutanés (associée à des IgE spécifiques dans 23 cas). Les épreuves fonctionnelles respiratoires ont été réalisées chez tous les patients, une mesure de l'hyperréactivité bronchique non spécifique chez 19 d'entre eux, 14 ont enregistré leur débit de pointe en période de travail et de congés, un test de provocation bronchique réaliste a été effectué dans 11 cas. Le suivi évolutif a été étudié chez 9 patients. Résultats. ˆ L'âge moyen des patients est de 27,9 ans ; 19 d'entre eux sont boulangers. Dans deux tiers des cas une rhinite est associée, la durée d'exposition avant l'apparition des symptômes est de 6 ans pour l'asthme et de 3 ans pour la rhinite. Trois patients seulement ont un asthme intermittent, la majorité d'entre eux (19 cas) a un asthme persistant modéré. La sensibilisation à la farine de blé est démontrée dans 21 cas sur 23. Une co-sensibilisation à la farine de seigle est observée dans 14 cas sur 16. Un syndrome obstructif intercritique n'est mis en évidence que dans 3 cas. L'hyperréactivité bronchique non spécifique est augmentée chez 14 patients sur 19. Le diagnostic a été confirmé chez 14 patients par l'étude des enregistrements du débit de pointe en période de travail et de congés. Dans 11 cas, le diagnostic est établi par la positivité du test de provocation bronchique réaliste à la farine (réaction immédiate dans tous les cas, double dans un cas, réaction immédiate prolongée dans 6 cas). L'évolution clinique étudiée chez 9 patients dont 4 ont eu une éviction complète montre que l'état clinique des asthmatiques de stade III ne s'améliore pas malgré un traitement par corticoïdes inhalés. Le devenir professionnel conduit souvent à une perte d'emploi ou à un reclassement professionnel (dans 4 cas sur 6). Conclusion. ˆ Le diagnostic d'asthme professionnel à la farine doit être établi par étapes : l'algorithme décisionnel basé sur un interrogatoire effectué par un clinicien expert se base successivement sur les résultats des tests immunologiques, l'enregistrement du débit de pointe en période de travail et de repos et le test de provocation bronchique.

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[93] - van Kampen V, Rabstein S, Sander I, Merget R, Brüning T, Broding HC, et al. Prediction of challenge test results by flour-specific IgE and skin prick test in symptomatic bakers. Allergy 2008;63:897-902

BACKGROUND: Wheat and rye flours are among the most important allergens causing occupational asthma. Usually, the diagnosis of baker's asthma is based on inhalation challenge tests with flours. AIMS OF THE STUDY: To evaluate the relevance of flour-specific serum immunoglobulin E (IgE) and skin prick test (SPT) in the diagnosis of baker's asthma and to define flour-specific IgE concentrations and wheal sizes that allow a prediction of the outcome of challenge testing . METHODS: Bronchial and nasal challenge tests with wheat (rye) flour were performed in 71 (95) symptomatic bakers. Determinations of flour-specific IgE as well as SPTs were performed in all subjects. Analyses included the calculation of sensitivity, specificity, positive (PPV) and negative predictive values (NPV) at different IgE concentrations and different wheal sizes, and receiver-operating characteristics (ROC) plots with the challenge result as gold standard . RESULTS: Thirty-seven bakers were positive in the challenge with wheat flour, while 63 were positive with rye flour. Depending on the flour-specific IgE concentrations (wheal size), PPV was 74-100% (74-100%) for wheat and 82-100% (91-100%) for rye flour, respectively. The minimal cut-off values with a PPV of 100% were 2.32 kU/l (5.0 mm) for wheat flour and 9.64 kU/l (4.5 mm) for rye flour. The shapes of the ROC plots were similar for wheat and rye flour . CONCLUSION: High concentrations of flour-specific IgE and clear SPT results in symptomatic bakers are good predictors for a positive challenge test. Challenge tests with flours may be avoided in strongly sensitized bakers.

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[94] - Walusiak J, Palczynski C, Hanke W, Wittczak T, Krakowiak A, Gorski P. The risk factors of occupational hypersensitivity in apprentice bakers -- the predictive value of atopy markers. Int Arch Occup Environ Health 2002;75(Suppl.):S117-S121

OBJECTIVES: The aim of the study was to assess the predictive value of known risk factors of asthma, such as atopy, exposure to pet allergens at home, and tobacco smoking, in predicting the occurrence of occupational respiratory allergy due to high-molecular-weight allergens. METHODS: A questionnaire study, skin-prick tests (SPTs) for common and occupational allergens, and evaluation of total and - in selected cases - specific IgE, were performed in 357 apprentice bakers before and after a year of vocational training. RESULTS: Mean age of examined subjects was 17.2+/-0.5 years. The prevalence of newly developed symptoms was 7% for rhinitis, 3.1% for chest symptoms, and 3.6% for skin symptoms. The frequency of at least one positive SPT result changed from 17.9% to 24.4% after the 1st year of vocational training, including SPTs for common allergens - from 16.8% to 22.7%, and for occupational allergens - from 2% to 8%. The proportion of subjects with elevated total IgE level increased from 38.7% to 44.3%. Generally, after a year of vocational training 9.2% of examined subjects presented hypersensitivity to occupational allergens. Logistic regression analysis revealed that positive results of SPTs for common allergens (odds ratio (OR) =4.4; 95% confidence intervals (CI) 1.9, 10.27) and elevated IgE level (OR=3.6; 95%CI 1.55, 8.57) were significant risk factors of hypersensitivity to occupational allergens. CONCLUSIONS: In apprentice bakers hypersensitivity to occupational allergens develops even during vocational training. SPTs for common allergens, performed before apprentices started their vocational training, would enable the identification of subjects at the highest risk of sensitisation to occupational allergens.

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[95] - Rosmaninho I, Delgado L, Morete A, Costa T, Ferraz de Oliveira J, Castel-Branco G. IgE sensitization to gliadin and cereal food allergy in baker’s asthma. EAACI 21th Congress, Naples, 1-5 June, 2002, Poster n°316

Cereal allergy may develop after ingestion or occupational exposure to cereal dust ˆ baker‚s asthma. The main IgE response is usually directed to albumin and globulin fractions, but recently wheat gliadin was identified as a prominent allergen in cases of severe IgE mediated reactions - atopic dermatitis and food anaphylaxis. Aims: to study the presence of cereal food allergy in baker's asthma and its relation with IgE sensitization to gliadin and other cereal allergens. Patients and methods: we included 10 patients with baker's asthma, with mean age of 40,7 years all male. Skin Prick tests (SPT) were performed to cereal grains (wheat, rye, barley, oats, corn), gliadin, a-amylase (from Aspergillus oryzae), common inhalants (house dust mites, pollen) and storage mites - ALK/ABELLÓ Results: in all patients the diagnosis of baker's asthma was done by work related changes in peak expiratory flow and specific bronchial challenge. Mean exposure to cereal flour was 21 years (range 1 - 45). Seven were still working and had bronchial symptoms and rhinitis with seasonal aggravation. Of the three patients away from work two had seasonal rhinitis and one intermittent asthma. Three patients had foodˆrelated symptoms one with anaphylaxis (after quitting work) and two with respiratory symptoms after cereal ingestion. All were sensitized to a cereal flour mixture and food panel ( wheat, rye, oats, rice and corn) and three were a amylase positive. Five patients were SPT positive to gliadin, but only one had symptoms with wheat ingestion. Nine bakers were sensitized to grass and /or weed pollen and three were sensitized to house dust mite and storage mites. Conclusion: although a baker highly sensitized to wheat and gliadin developed food-related anaphylaxis after cereal ingestion, in our patients with baker's asthma we did not find an association between IgE sensitazation to gliadin and food-related symptoms.

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[96] - Fourgaut G, Popin E, Kopferschmitt MC, Newinger G, Pauli G. L'asthme à la farine : étude clinique de 27 cas (nécessité d'un algorithme décisionnel). Rev Fr Allergol Immunol Clin 2002;42:633-639

Objectifs. ˆ À partir de l'étude de patients retenus comme ayant un asthme professionnel dans le milieu de la boulangerie par des cliniciens experts, les auteurs précisent l'apport des différents examens complémentaires. Matériel et méthodes. ˆ Les dossiers de 27 sujets diagnostiqués entre 1983 et 1999, présentant un asthme professionnel de gravité variable, sont étudiés. Le bilan allergologique complet a été effectué avec recherche des sensibilités à la farine par tests cutanés (associée à des IgE spécifiques dans 23 cas). Les épreuves fonctionnelles respiratoires ont été réalisées chez tous les patients, une mesure de l'hyperréactivité bronchique non spécifique chez 19 d'entre eux, 14 ont enregistré leur débit de pointe en période de travail et de congés, un test de provocation bronchique réaliste a été effectué dans 11 cas. Le suivi évolutif a été étudié chez 9 patients. Résultats. ˆ L'âge moyen des patients est de 27,9 ans ; 19 d'entre eux sont boulangers. Dans deux tiers des cas une rhinite est associée, la durée d'exposition avant l'apparition des symptômes est de 6 ans pour l'asthme et de 3 ans pour la rhinite. Trois patients seulement ont un asthme intermittent, la majorité d'entre eux (19 cas) a un asthme persistant modéré. La sensibilisation à la farine de blé est démontrée dans 21 cas sur 23. Une co-sensibilisation à la farine de seigle est observée dans 14 cas sur 16. Un syndrome obstructif intercritique n'est mis en évidence que dans 3 cas. L'hyperréactivité bronchique non spécifique est augmentée chez 14 patients sur 19. Le diagnostic a été confirmé chez 14 patients par l'étude des enregistrements du débit de pointe en période de travail et de congés. Dans 11 cas, le diagnostic est établi par la positivité du test de provocation bronchique réaliste à la farine (réaction immédiate dans tous les cas, double dans un cas, réaction immédiate prolongée dans 6 cas). L'évolution clinique étudiée chez 9 patients dont 4 ont eu une éviction complète montre que l'état clinique des asthmatiques de stade III ne s'améliore pas malgré un traitement par corticoïdes inhalés. Le devenir professionnel conduit souvent à une perte d'emploi ou à un reclassement professionnel (dans 4 cas sur 6). Conclusion. ˆ Le diagnostic d'asthme professionnel à la farine doit être établi par étapes : l'algorithme décisionnel basé sur un interrogatoire effectué par un clinicien expert se base successivement sur les résultats des tests immunologiques, l'enregistrement du débit de pointe en période de travail et de repos et le test de provocation bronchique.

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[97] - Walusiak J, Krawczyk-Adamus P, Wiszniewska M, Dudek W, Niececierenko E, Palczynski C. Diagnostic value of specific IgE in baker's asthma and rhinitis due to wheat flour. Allergy Clin Immunol Int 2005;17(Suppl. 1):388

Background: The purpose of the study was to evaluate specificity, sensitivity and positive and negative predictive values (PPV, NPV) of allergen specific IgE in bakers with occupational bronchial allergy. Material and methods: The gold standard for the diagnosis of occupational asthma and/or rhinitis was specific inhalation challenge test. 231 bakers participated in the study. Occupational asthma due to wheat flour was recognized in 101 subjects, occupational rhinitis in 96 bakers and 106 patients were found not to have occupational allergy. 5 subjects with asthma due to alfa-amylase were excluded from the analysis. In all subjects SPT to common and occupational allergens, wheat, rye flour (f4, f5, fx20 from Pharmacia, Upsala, Sweden) and alfa-amylase specific IgE and histamine challenge test were performed. Results: In diagnosing baker's asthma the sensitivity of specific IgE was 60.4%, specificity 26.4%, PPV 68.5%, NPV 66.1%). In occupational rhinitis CAP RAST sensitivity was 76,5%, specificity 26.4%, PPV 31.7%, NPV 95.1%). All subjects sensitized to wheat flour were concurrently sensitized to rye proteins - differences between CAP RAST f4 and f5 results did not exceed one class. Moreover, significant correlation between the results of fx20 and f4/f5 results was found. Conclusions: The results support the thesis that specific inhalation challenge tests are needed when diagnosing bakers‚ asthma. The predictive value of the allergen specific IgE is not sufficient.

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[98] - Armentia A, Rodriguez R, Callejo A, Martin-Esteban M, Martin-Santos JM, Salcedo G, et al. Allergy after ingestion or inhalation of cereals involves similar allergens in different ages. Clin Exp Allergy 2002;32:1216-1222

Background Cereals are among the major foods that account for food hypersensitivity reactions. Salt-soluble proteins appear to be the most important allergens contributing to the asthmatic response. In contrast, very limited information is available regarding cereal allergens responsible for allergic reactions after ingestion of cereal proteins. Objective The aim of this study was to evaluate the allergenic reactivity of ingested and inhaled cereal allergens in different ages, in order to investigate if the response to different allergens would depend on the sensitization route. Methods We included 66 patients in three groups. Group 1: 40 children aged 3 to 6 months who suffered from diarrhoea, vomiting, eczema or weight loss after the introduction of cereal formula in their diet and in which a possibility of coeliac disease was discarded. Group 2: 18 adults with food allergy due to cereals tested by prick tests, specific IgE and food challenge. Group 3: eight patients previously diagnosed as having baker's asthma. Sera pool samples were collected from each group of patients and IgE immunoblotting was performed. Results We found an important sensitization to cereal in the 40 children. The most important allergens were wheat followed by barley and rye. Among the adults with cereal allergy, sensitization to other allergens was common, especially to Lolium perenne (rye grass) pollen. Immunoblotting showed similar allergenic detection in the three groups. Conclusion Clinically significant reactivity to cereal may be observed in early life. Inhalation and ingestion routes causing cereal allergy seem to involve similar allergens. The diet control was more effective in children. The possibility of cereal allergy after the introduction of cereal formula during the lactation period should not be underestimated.

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[99] - Palacin A, Quirce S, Armentia A, Fernández-Nieto M, Pacios LF, Asensio T, et al. Wheat lipid transfer protein is a major allergen associated with baker's asthma,. J Allergy Clin Immunol 2007;120:1132-1138

BACKGROUND: Baker's asthma is a frequent occupational allergic disorder mainly caused by inhalation of cereal flours. Lipid transfer proteins (LTPs) constitute a family of plant food panallergens, but their role as inhalant and wheat allergens is still unclear . OBJECTIVE: We sought to explore the involvement of wheat LTPs in baker's asthma caused by wheat flour sensitization . METHODS: Forty patients with occupational asthma caused by wheat flour inhalation were studied. Wheat LTP, Tri a 14, was purified by using a 2-step chromatographic protocol and characterized by N-terminal amino acid sequencing and 3-dimensional modeling. Its reactivity was confirmed by means of IgE immunodetection, ELISA and ELISA-inhibition assays, and skin prick tests . RESULTS: Specific IgE to Tri a 14 was found in 60% of 40 individual sera from patients with baker's asthma, and the purified allergen elicited positive skin prick test reactions in 62% of 24 of these patients. Tri a 14 and peach LTP, Pru p 3, showed a sequence identity of 45%, but the low cross-reactivity between both allergens detected in several individual sera reflected great differences in their 3-dimensional IgE-binding regions . CONCLUSIONS: Wheat LTP is a major inhalant allergen associated with baker's asthma caused by wheat flour sensitization. Poor cross-reactivity with its peach homolog was found in some patients. CLINICAL IMPLICATIONS: LTPs can be considered relevant inhalant allergens linked to respiratory disorders. LTP from wheat (Tri a 14) can be used as a helpful tool for the diagnosis of baker's asthma.

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[100] - Bittner C, Grassau B, Frenzel K, Baur X. Identification of wheat gliadins as an allergen family related to baker’s asthma. J Allergy Clin Immunol 2008;121:744-749

BACKGROUND: Flour is still one of the most common causes of occupational asthma worldwide. Thus far, little is known about the relevant allergens causing baker's asthma. Therefore the reliability of current diagnostic procedures is insufficient. Only few of the suspected causative wheat allergens have been hitherto characterized on the molecular level . OBJECTIVE: The aim was to identify and characterize unknown wheat allergens related to baker's asthma to improve the reliability of diagnostic procedures . METHODS: A wheat pJuFo cDNA phage display library was created and screened for IgE binding to wheat proteins with pooled sera from patients with baker's asthma. After identifying an alphabeta-gliadin, the frequency of sensitization was investigated by means of ELISA screening of 153 bakers' sera with the recombinant alphabeta-gliadin. Furthermore, the allergenicity of native total gliadin (alphabeta, gamma, omega) was analyzed by means of ImmunoCAP . RESULTS: One cDNA clone was identified as an alphabeta-gliadin. Serum IgE antibodies to the recombinant allergen were found in 12% of bakers with occupational asthma. Of the asthmatic bakers, 33% showed sensitization to native total gliadin; 4% of them had negative results on routine IgE testing with wheat extract . CONCLUSIONS: Gliadins represent a newly discovered family of inhalable allergens in baker's asthma. This finding demonstrates that water-insoluble proteins might also represent causative allergens.

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[101] - Delgado L, Rosmaninho I, Sequeira M, Cunha L. Cereal food allergy developing after occupational avoidance in a patient with baker’s asthma. EAACI 21th Congress, Naples, 1-5 June, 2002, Poster n°272

Cereal grains are recognized as the cause of adverse reaction in some patients exposed to grain or flour by either inhalation or ingestion. The authors describe a 38-year-old patient who developed occupational respiratory symptoms (asthma and rhinitis ) three months after starting work in a bakery. Skin Prick Tests (SPT) were positive to grass pollen and cereal grain mixture, with a total IgE=1142KUA/L. Because of clinical and functional worsening after a 2 years follow-up period, in spite of reduced exposure and treatment, the patient had to get away definitely from the bakery. Four years later, he developed anaphylactic symptoms immediately after wheat and rye ingestion, At this time point SPT. Were positive to grass pollen and with a commercial panel of food allergens - wheat, rye, barley and oat flour and gliadin, "Prick -to-prick-tests were positive to wheat, rye, corn and barley flour. Specific IgE (UniCAP Pharmacia) was positive to wheat flour (925KUA/L), rye flour (1023KUA/L, corn flour (22KUA/L), and gliadin (874KUA/L), grass pollen mixture(gx1=7KUA/L). CAP Rast inhibition test showed cross-reactivity between gliadin and the common flours of wheat (84,4% inhibition), rye, (77,5%). These results suggest that IgE sensitazation to gliadin may be related to severe food-allergy symptoms in patients with previous inhalatory exposure to cereal flours.

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[102] - Fourgaut G, Popin E, Kopferschmitt MC, Newinger G, Pauli G. L'asthme à la farine : étude clinique de 27 cas (nécessité d'un algorithme décisionnel). Rev Fr Allergol Immunol Clin 2002;42:633-639

Objectifs. ˆ À partir de l'étude de patients retenus comme ayant un asthme professionnel dans le milieu de la boulangerie par des cliniciens experts, les auteurs précisent l'apport des différents examens complémentaires. Matériel et méthodes. ˆ Les dossiers de 27 sujets diagnostiqués entre 1983 et 1999, présentant un asthme professionnel de gravité variable, sont étudiés. Le bilan allergologique complet a été effectué avec recherche des sensibilités à la farine par tests cutanés (associée à des IgE spécifiques dans 23 cas). Les épreuves fonctionnelles respiratoires ont été réalisées chez tous les patients, une mesure de l'hyperréactivité bronchique non spécifique chez 19 d'entre eux, 14 ont enregistré leur débit de pointe en période de travail et de congés, un test de provocation bronchique réaliste a été effectué dans 11 cas. Le suivi évolutif a été étudié chez 9 patients. Résultats. ˆ L'âge moyen des patients est de 27,9 ans ; 19 d'entre eux sont boulangers. Dans deux tiers des cas une rhinite est associée, la durée d'exposition avant l'apparition des symptômes est de 6 ans pour l'asthme et de 3 ans pour la rhinite. Trois patients seulement ont un asthme intermittent, la majorité d'entre eux (19 cas) a un asthme persistant modéré. La sensibilisation à la farine de blé est démontrée dans 21 cas sur 23. Une co-sensibilisation à la farine de seigle est observée dans 14 cas sur 16. Un syndrome obstructif intercritique n'est mis en évidence que dans 3 cas. L'hyperréactivité bronchique non spécifique est augmentée chez 14 patients sur 19. Le diagnostic a été confirmé chez 14 patients par l'étude des enregistrements du débit de pointe en période de travail et de congés. Dans 11 cas, le diagnostic est établi par la positivité du test de provocation bronchique réaliste à la farine (réaction immédiate dans tous les cas, double dans un cas, réaction immédiate prolongée dans 6 cas). L'évolution clinique étudiée chez 9 patients dont 4 ont eu une éviction complète montre que l'état clinique des asthmatiques de stade III ne s'améliore pas malgré un traitement par corticoïdes inhalés. Le devenir professionnel conduit souvent à une perte d'emploi ou à un reclassement professionnel (dans 4 cas sur 6). Conclusion. ˆ Le diagnostic d'asthme professionnel à la farine doit être établi par étapes : l'algorithme décisionnel basé sur un interrogatoire effectué par un clinicien expert se base successivement sur les résultats des tests immunologiques, l'enregistrement du débit de pointe en période de travail et de repos et le test de provocation bronchique.

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[103] - Armentia A, Rodriguez R, Callejo A, Martin-Esteban M, Martin-Santos JM, Salcedo G, et al. Allergy after ingestion or inhalation of cereals involves similar allergens in different ages. Clin Exp Allergy 2002;32:1216-1222

Background Cereals are among the major foods that account for food hypersensitivity reactions. Salt-soluble proteins appear to be the most important allergens contributing to the asthmatic response. In contrast, very limited information is available regarding cereal allergens responsible for allergic reactions after ingestion of cereal proteins. Objective The aim of this study was to evaluate the allergenic reactivity of ingested and inhaled cereal allergens in different ages, in order to investigate if the response to different allergens would depend on the sensitization route. Methods We included 66 patients in three groups. Group 1: 40 children aged 3 to 6 months who suffered from diarrhoea, vomiting, eczema or weight loss after the introduction of cereal formula in their diet and in which a possibility of coeliac disease was discarded. Group 2: 18 adults with food allergy due to cereals tested by prick tests, specific IgE and food challenge. Group 3: eight patients previously diagnosed as having baker's asthma. Sera pool samples were collected from each group of patients and IgE immunoblotting was performed. Results We found an important sensitization to cereal in the 40 children. The most important allergens were wheat followed by barley and rye. Among the adults with cereal allergy, sensitization to other allergens was common, especially to Lolium perenne (rye grass) pollen. Immunoblotting showed similar allergenic detection in the three groups. Conclusion Clinically significant reactivity to cereal may be observed in early life. Inhalation and ingestion routes causing cereal allergy seem to involve similar allergens. The diet control was more effective in children. The possibility of cereal allergy after the introduction of cereal formula during the lactation period should not be underestimated.

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[104] - van Kampen V, Rabstein S, Sander I, Merget R, Brüning T, Broding HC, et al. Prediction of challenge test results by flour-specific IgE and skin prick test in symptomatic bakers. Allergy 2008;63:897-902

BACKGROUND: Wheat and rye flours are among the most important allergens causing occupational asthma. Usually, the diagnosis of baker's asthma is based on inhalation challenge tests with flours. AIMS OF THE STUDY: To evaluate the relevance of flour-specific serum immunoglobulin E (IgE) and skin prick test (SPT) in the diagnosis of baker's asthma and to define flour-specific IgE concentrations and wheal sizes that allow a prediction of the outcome of challenge testing . METHODS: Bronchial and nasal challenge tests with wheat (rye) flour were performed in 71 (95) symptomatic bakers. Determinations of flour-specific IgE as well as SPTs were performed in all subjects. Analyses included the calculation of sensitivity, specificity, positive (PPV) and negative predictive values (NPV) at different IgE concentrations and different wheal sizes, and receiver-operating characteristics (ROC) plots with the challenge result as gold standard . RESULTS: Thirty-seven bakers were positive in the challenge with wheat flour, while 63 were positive with rye flour. Depending on the flour-specific IgE concentrations (wheal size), PPV was 74-100% (74-100%) for wheat and 82-100% (91-100%) for rye flour, respectively. The minimal cut-off values with a PPV of 100% were 2.32 kU/l (5.0 mm) for wheat flour and 9.64 kU/l (4.5 mm) for rye flour. The shapes of the ROC plots were similar for wheat and rye flour . CONCLUSION: High concentrations of flour-specific IgE and clear SPT results in symptomatic bakers are good predictors for a positive challenge test. Challenge tests with flours may be avoided in strongly sensitized bakers.

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[105] - Baldo BA, Krilis S, Wrigley CW. Hypersensitivity to inhaled flour allergens. Comparison between cereals. Allergy 1980;35:45-56

Radioallergosorbent testing (RAST) of sera from subjects sensitized to wheat and rye flour indicated that there is significant reaction with seed extracts of 12 cereals (wheat, durum wheat, triticale, cereal rye, barley, rye grass, oats, canary grass, rice, maize, sorghum and Johnson grass). Results were evaluated in terms of taxonomic relationships and of the electrophoretically determined protein composition of the cereal extracts. RAST uptakes were uniformly low in sera from four rhinitic bakers, yet were significantly above the levels for non-allergic and cord sera. Much higher RAST uptakes were obtained with sera from four asthmatic bakers when tested with wheat and its close relatives, but there was still reasonably high reactivity with more distantly related cereals. RAST inhibition experiments indicated in a more direct way the extent of cross-reactivity between grain extracts of wheat, rye, barley and oats. One baker had a history of more severe attacks of breathlessness following inhalation of rye flour compared with wheat flour. This was confirmed by bronchial challenge testing, but the comparison was not obviously consistent with the results of prick testing or estimation of histamine released from his leucocytes. The results as a whole suggested that the bran layers of cereal grains are at least as allergenic as flour.

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[106] - Gomez L, Martin E, Hernandez D, Sanchez-Monge R, Barber D, del Pozo V, et al. Members of the alpha-amylase inhibitors family from wheat endosperm are major allergens associated with baker's asthma. FEBS Lett 1990;261:85-88

The major antigens or IgE binding components from wheat flour were identified. 35 sera from patients with bakers' asthma were used to analyse the reaction with wheat salt-soluble proteins. A 15 kD SDS-PAGE band which reacted with all sera tested was found. Purified members of the [alpha]-amylase inhibitor family, which are the main components of the 15 kDa band, were recognized by specific IgE when tested with a pool of reactive sera. Immunodetection after 2-dimensional electrophoretic fractionation of crude inhibitor preparations from [bread and durum] wheat endosperms also detected several inhibitor subunits as major low-mol.-wt. allergens

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[107] - Amano M, Ogawa H, Kojima K, Kamidaira T, Suetsugu S, Yoshihama M, et al. Identification of the major allergens in wheat flour responsible for baker's asthma. Biochem J 1998;330:1229-1234

Bakers' asthma, a typical occupational allergic disease, is a serious problem in the food industries. In this study, purification and identification of major allergens recognized by IgE in sera of allergic patients were performed. Major immunoreactive proteins were purified from the albumin fraction [of wheat flour] by gel filtration on a Toyopearl HW-50 column followed by reverse-phase HPLC. The N-terminal amino acid sequences and molecular masses measured by MS indicated that the major immunoreactive proteins are members of the [alpha]-amylase inhibitor family, 0.19 and 0.28. Significant leukotriene release by each purified protein was observed in cell-associated stimulation tests, suggesting in vivo activity of these antigens. Carbohydrate analyses of major allergens indicated that they are monoglycosylated but not N-glycosylated in spite of the presence of a potential N-glycosylation site. Recombinant 0.19 expressed in Escherichia coli showed the same reactivity with IgE as native wheat 0.19 in Western blotting and ELISA using methyl vinyl ether maleic anhydride co-polymer as an immobilizing reagent, suggesting that the allergenic epitopes are located in the peptide portions

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[108] - Weiss W, Huber G, Engel KH, Pethran A, Dunn MJ, Gooley AA, et al. Identification and characterization of wheat grain albumin/globulin allergens. Electrophoresis 1997;18:826-833

Bakers' asthma, an immediate-type allergic response to the inhalation of cereal flours, is an important occupational disease among workers of the baking and milling industries, and the salt-soluble proteins of wheat and rye flour dust are considered the most relevant allergens. In order to identify the characterize the major IgE-binding proteins, the polypeptide composition of the albumin/globulin protein fraction obtained from different [wheat] cultivars was analysed by sodium dodecyl sulphate-polyacrylamide gel electrophoresis (SDS-PAGE), and high-resolution 2-dimensional polyacrylamide electrophoresis with immobilized pH gradients in the first dimension (IPG-Dalt), followed by immunoblotting with sera from asthmatic bakers. Relevant allergens were isolated by micropreparative IPG-Dalt, and blotting onto polyvinylidenedifluoride membranes and identified by amino acid composition analysis or N-terminal amino acid sequence analysis. SDS-PAGE, IPG-Dalt, and immunoblotting demonstrated that the sera of the bakers allergic to flour contained IgE antibodies which bound to numerous albumin/globulin polypeptides in the 70, 55, 35, 26-28 and 14-18 kDa areas. More detailed investigations using IPG-Dalt revealed cultivar-specific differences in IgE-binding. It was also demonstrated that the majority of the allergens were not single polypeptide spots, but consisted of up to 10 isoforms of similar molecular mass but different isoelectric points. Amino acid composition analysis and N-terminal amino acid sequence analysis, which were performed for 9 allergens located in the 14-18, 26-28 and 35 kDa areas, revealed homologies to amylase/protease inhibitors, acyl-CoA oxidase and fructose-bisphosphate-aldolase from wheat, barley, maize and rice, respectively

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[109] - Fourgaut G, Popin E, Kopferschmitt MC, Newinger G, Pauli G. L'asthme à la farine : étude clinique de 27 cas (nécessité d'un algorithme décisionnel). Rev Fr Allergol Immunol Clin 2002;42:633-639

Objectifs. ˆ À partir de l'étude de patients retenus comme ayant un asthme professionnel dans le milieu de la boulangerie par des cliniciens experts, les auteurs précisent l'apport des différents examens complémentaires. Matériel et méthodes. ˆ Les dossiers de 27 sujets diagnostiqués entre 1983 et 1999, présentant un asthme professionnel de gravité variable, sont étudiés. Le bilan allergologique complet a été effectué avec recherche des sensibilités à la farine par tests cutanés (associée à des IgE spécifiques dans 23 cas). Les épreuves fonctionnelles respiratoires ont été réalisées chez tous les patients, une mesure de l'hyperréactivité bronchique non spécifique chez 19 d'entre eux, 14 ont enregistré leur débit de pointe en période de travail et de congés, un test de provocation bronchique réaliste a été effectué dans 11 cas. Le suivi évolutif a été étudié chez 9 patients. Résultats. ˆ L'âge moyen des patients est de 27,9 ans ; 19 d'entre eux sont boulangers. Dans deux tiers des cas une rhinite est associée, la durée d'exposition avant l'apparition des symptômes est de 6 ans pour l'asthme et de 3 ans pour la rhinite. Trois patients seulement ont un asthme intermittent, la majorité d'entre eux (19 cas) a un asthme persistant modéré. La sensibilisation à la farine de blé est démontrée dans 21 cas sur 23. Une co-sensibilisation à la farine de seigle est observée dans 14 cas sur 16. Un syndrome obstructif intercritique n'est mis en évidence que dans 3 cas. L'hyperréactivité bronchique non spécifique est augmentée chez 14 patients sur 19. Le diagnostic a été confirmé chez 14 patients par l'étude des enregistrements du débit de pointe en période de travail et de congés. Dans 11 cas, le diagnostic est établi par la positivité du test de provocation bronchique réaliste à la farine (réaction immédiate dans tous les cas, double dans un cas, réaction immédiate prolongée dans 6 cas). L'évolution clinique étudiée chez 9 patients dont 4 ont eu une éviction complète montre que l'état clinique des asthmatiques de stade III ne s'améliore pas malgré un traitement par corticoïdes inhalés. Le devenir professionnel conduit souvent à une perte d'emploi ou à un reclassement professionnel (dans 4 cas sur 6). Conclusion. ˆ Le diagnostic d'asthme professionnel à la farine doit être établi par étapes : l'algorithme décisionnel basé sur un interrogatoire effectué par un clinicien expert se base successivement sur les résultats des tests immunologiques, l'enregistrement du débit de pointe en période de travail et de repos et le test de provocation bronchique.

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[110] - Sanchez-Monge R, Garcia-Casado G, Lopez-Otin C, Armentia A, Salcedo G. Wheat flour peroxidase is a prominent allergen associated with baker's asthma. Clin Exp Allergy 1997;27:1130-1137

BACKGROUND: Putative wheat allergens with molecular sizes around 35kDa have been repeatedly detected in immunoblots using sera from patients with baker's asthma. However, none of these allergens had been previously isolated. OBJECTIVE: To purify and characterize a major component of the 35 kDa allergenic band which seems to be present in flour from diploid, tetraploid (pasta) and hexaploid (bread) wheats. METHODS: Gel-filtration chromatography followed by RP-HPLC have allowed the purification of a new wheat allergen. Immunodetection with sera from allergic patients and with a specific serum for asparagine-linked complex glycans, as well as amino acid sequencing, were used to identify the isolated protein. RESULTS: A 36 kDa allergen has been purified from wheat flour. Its N-terminal and internal sequences, N-linked glycans, and enzymatic activity indicated that this allergen is a seed-specific peroxidase. Sera from six out of 10 patients hypersensitive to wheat flour displayed positive reactions when assayed against the purified dot-blotted allergen. CONCLUSION: Seed-specific peroxidases from cereals (flours) seem to be important allergens in hypersensitive diseases associated with the manipulation of these plant materials. A new enzyme has thus been involved in IgE-mediated diseases.

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[111] - Rozynek P, Sander I, Appenzeller U, Crameri R, Baur X, Clarke B, et al. TPIS an IgE-binding wheat protein. Allergy 2002;57:463

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[112] - Weiss W, Huber G, Engel KH, Pethran A, Dunn MJ, Gooley AA, et al. Identification and characterization of wheat grain albumin/globulin allergens. Electrophoresis 1997;18:826-833

Bakers' asthma, an immediate-type allergic response to the inhalation of cereal flours, is an important occupational disease among workers of the baking and milling industries, and the salt-soluble proteins of wheat and rye flour dust are considered the most relevant allergens. In order to identify the characterize the major IgE-binding proteins, the polypeptide composition of the albumin/globulin protein fraction obtained from different [wheat] cultivars was analysed by sodium dodecyl sulphate-polyacrylamide gel electrophoresis (SDS-PAGE), and high-resolution 2-dimensional polyacrylamide electrophoresis with immobilized pH gradients in the first dimension (IPG-Dalt), followed by immunoblotting with sera from asthmatic bakers. Relevant allergens were isolated by micropreparative IPG-Dalt, and blotting onto polyvinylidenedifluoride membranes and identified by amino acid composition analysis or N-terminal amino acid sequence analysis. SDS-PAGE, IPG-Dalt, and immunoblotting demonstrated that the sera of the bakers allergic to flour contained IgE antibodies which bound to numerous albumin/globulin polypeptides in the 70, 55, 35, 26-28 and 14-18 kDa areas. More detailed investigations using IPG-Dalt revealed cultivar-specific differences in IgE-binding. It was also demonstrated that the majority of the allergens were not single polypeptide spots, but consisted of up to 10 isoforms of similar molecular mass but different isoelectric points. Amino acid composition analysis and N-terminal amino acid sequence analysis, which were performed for 9 allergens located in the 14-18, 26-28 and 35 kDa areas, revealed homologies to amylase/protease inhibitors, acyl-CoA oxidase and fructose-bisphosphate-aldolase from wheat, barley, maize and rice, respectively

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[113] - Sandiford CP, Tatham AS, Fido R, Welch JA, Jones MG, Tee RD, et al. Identification of the major water/salt insoluble wheat proteins involved in cereal hypersensitivity. Clin Exp Allergy 1997;27:1120-1129

BACKGROUND: Several studies have investigated water/salt soluble proteins which comprise 50% of the proteins in wheat. The remaining 50% of wheat proteins, are water/salt insoluble proteins of which there is limited information on their role in cereal hypersensitivity. OBJECTIVES: To investigate the allergenicity of the water/salt insoluble gliadin and glutenin proteins (prolamins). METHODS: RAST, electrophoresis and Western blotting were used to identify water/salt insoluble wheat allergens. Competitive RAST inhibition was conducted to investigate cross-reactivity between prolamins and water/salt soluble wheat proteins. RESULTS: Specific IgE to alpha-gliadin and to total glutenins were detected in all sera. IgE to beta-, gamma-, fast omega-, and slow omega-gliadin were present in lower numbers of sera. Prolamin allergens of 90-11 kDa were identified by immunoblotting. Water/salt soluble proteins crossreacted with alpha-gliadin and total glutenins. CONCLUSIONS: Individuals who are hypersensitive to water/salt soluble wheat proteins produce specific IgE to water/salt insoluble wheat proteins. Western blotting has shown that gliadins, glutenins and proteins with similar molecular weights as the endogenous water/salt soluble wheat enzyme inhibitors are important allergens. Alpha and fast omega- are the most allergenic gliadins. The water/salt insoluble proteins share cross-reacting epitopes with water/salt soluble proteins. These data show that the numbers of proteins involved in the development of cereal hypersensitivity is greater than previously believed and that the development of specific IgE to alpha-gliadin may in part depend on the presence of cross-reacting antibodies to water/salt soluble flour allergens.

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[114] - Weiss W, Huber G, Engel KH, Pethran A, Dunn MJ, Gooley AA, et al. Identification and characterization of wheat grain albumin/globulin allergens. Electrophoresis 1997;18:826-833

Bakers' asthma, an immediate-type allergic response to the inhalation of cereal flours, is an important occupational disease among workers of the baking and milling industries, and the salt-soluble proteins of wheat and rye flour dust are considered the most relevant allergens. In order to identify the characterize the major IgE-binding proteins, the polypeptide composition of the albumin/globulin protein fraction obtained from different [wheat] cultivars was analysed by sodium dodecyl sulphate-polyacrylamide gel electrophoresis (SDS-PAGE), and high-resolution 2-dimensional polyacrylamide electrophoresis with immobilized pH gradients in the first dimension (IPG-Dalt), followed by immunoblotting with sera from asthmatic bakers. Relevant allergens were isolated by micropreparative IPG-Dalt, and blotting onto polyvinylidenedifluoride membranes and identified by amino acid composition analysis or N-terminal amino acid sequence analysis. SDS-PAGE, IPG-Dalt, and immunoblotting demonstrated that the sera of the bakers allergic to flour contained IgE antibodies which bound to numerous albumin/globulin polypeptides in the 70, 55, 35, 26-28 and 14-18 kDa areas. More detailed investigations using IPG-Dalt revealed cultivar-specific differences in IgE-binding. It was also demonstrated that the majority of the allergens were not single polypeptide spots, but consisted of up to 10 isoforms of similar molecular mass but different isoelectric points. Amino acid composition analysis and N-terminal amino acid sequence analysis, which were performed for 9 allergens located in the 14-18, 26-28 and 35 kDa areas, revealed homologies to amylase/protease inhibitors, acyl-CoA oxidase and fructose-bisphosphate-aldolase from wheat, barley, maize and rice, respectively

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[115] - Bittner C, Grassau B, Frenzel K, Baur X. Identification of wheat gliadins as an allergen family related to baker’s asthma. J Allergy Clin Immunol 2008;121:744-749

BACKGROUND: Flour is still one of the most common causes of occupational asthma worldwide. Thus far, little is known about the relevant allergens causing baker's asthma. Therefore the reliability of current diagnostic procedures is insufficient. Only few of the suspected causative wheat allergens have been hitherto characterized on the molecular level . OBJECTIVE: The aim was to identify and characterize unknown wheat allergens related to baker's asthma to improve the reliability of diagnostic procedures . METHODS: A wheat pJuFo cDNA phage display library was created and screened for IgE binding to wheat proteins with pooled sera from patients with baker's asthma. After identifying an alphabeta-gliadin, the frequency of sensitization was investigated by means of ELISA screening of 153 bakers' sera with the recombinant alphabeta-gliadin. Furthermore, the allergenicity of native total gliadin (alphabeta, gamma, omega) was analyzed by means of ImmunoCAP . RESULTS: One cDNA clone was identified as an alphabeta-gliadin. Serum IgE antibodies to the recombinant allergen were found in 12% of bakers with occupational asthma. Of the asthmatic bakers, 33% showed sensitization to native total gliadin; 4% of them had negative results on routine IgE testing with wheat extract . CONCLUSIONS: Gliadins represent a newly discovered family of inhalable allergens in baker's asthma. This finding demonstrates that water-insoluble proteins might also represent causative allergens.

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[116] - Mittag D, Niggemann B, Sander I, Reese I, Fiedler EM, Worm M, et al. Immunoglobulin E-reactivity of wheat-allergic subjects (baker's asthma, food allergy, wheat-dependent, exercise-induced anaphylaxis) to wheat protein fractions with different solubility and digestibility. Mol Nutr Food Res 2004;48:380-389

Baker's asthma, food allergy to wheat, and wheat-dependent, exercise-induced anaphylaxis (WDEIA) are different clinical forms of wheat allergy. We investigated the correlation of solubility and digestion stability of wheat allergens with the IgE-reactivity patterns of different patient groups. Three wheat protein fractions were extracted according to their solubility: salt-soluble albumins and globulins, ethanol-soluble gliadins, and glutenins soluble only after treatment with detergents and reducing reagents. Sera from subjects with history of each variant of wheat allergy were characterized by CAP FEIA and immunoblotting. There was a high degree of heterogeneity of recognized allergens between the different subject groups as well as within these groups. However, subjects with WDEIA showed similar immunoglobulin E (IgE)-reactivity patterns to gliadins and especially to a 65 kDa protein. Subjects with baker's asthma as well as the food-allergic subjects had the most intense IgE-reactivity to the albumin/globulin fraction. The latter group additionally showed IgE-reactivity to the other fractions. Divergent results of immunoblotting and CAP-FEIA demonstrated that the detection of wheat-specific IgE highly depends on the applied method, thus the diagnostic tool must be carefully chosen. Most wheat allergens were rapidly digested as analyzed by determination of IgE-reactivity on immunoblots to wheat extracts after simulation of gastric and duodenal digestion. However, ethanol-soluble gliadins were stable to gastric enzymes and exhibit low solubility in gastric and duodenal fluids. Therefore, they are likely to be important in food allergy to wheat.

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[117] - Bouchez-Mahiout I, Snégaroff J, Boulenc E, Pecquet C, Choudat D, Raison-Peyron N, et al. Spécificité des protéines impliquées dans différentes formes d’allergie au blé. Rev Fr Allergol Immunol Clin 2007;47:285

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[118] - Palacin A, Quirce S, Armentia A, Fernández-Nieto M, Pacios LF, Asensio T, et al. Wheat lipid transfer protein is a major allergen associated with baker's asthma,. J Allergy Clin Immunol 2007;120:1132-1138

BACKGROUND: Baker's asthma is a frequent occupational allergic disorder mainly caused by inhalation of cereal flours. Lipid transfer proteins (LTPs) constitute a family of plant food panallergens, but their role as inhalant and wheat allergens is still unclear . OBJECTIVE: We sought to explore the involvement of wheat LTPs in baker's asthma caused by wheat flour sensitization . METHODS: Forty patients with occupational asthma caused by wheat flour inhalation were studied. Wheat LTP, Tri a 14, was purified by using a 2-step chromatographic protocol and characterized by N-terminal amino acid sequencing and 3-dimensional modeling. Its reactivity was confirmed by means of IgE immunodetection, ELISA and ELISA-inhibition assays, and skin prick tests . RESULTS: Specific IgE to Tri a 14 was found in 60% of 40 individual sera from patients with baker's asthma, and the purified allergen elicited positive skin prick test reactions in 62% of 24 of these patients. Tri a 14 and peach LTP, Pru p 3, showed a sequence identity of 45%, but the low cross-reactivity between both allergens detected in several individual sera reflected great differences in their 3-dimensional IgE-binding regions . CONCLUSIONS: Wheat LTP is a major inhalant allergen associated with baker's asthma caused by wheat flour sensitization. Poor cross-reactivity with its peach homolog was found in some patients. CLINICAL IMPLICATIONS: LTPs can be considered relevant inhalant allergens linked to respiratory disorders. LTP from wheat (Tri a 14) can be used as a helpful tool for the diagnosis of baker's asthma.

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[119] - Lehto M, Airaksinen L, Puustinen A, Nyman T, Hannula S, Toskala E, et al. Thaumatin-like protein and lipid transfer protein 2G are new allergens associated with baker’s asthma. Allergy 2008;63(suppl. 88):39-40

Background: Baker‚s asthma is one of the most common causes of occupational diseases. The main agents causing this disease are inhaled cereal flours especially wheat, although baking additives such as fungal alpha-amylase and xylanase are also important. The aim of the present study was to identify clinically important novel wheat allergens in baker‚s asthma. Methods: Putative wheat allergens were purified by chromatographic methods from salt-soluble protein extracts of wheat flour and used in skin prick tests. Serial 10-fold dilutions were utilized in skin prick tests (0.5-0.005 mg/mL). In total, 20 baker‚s asthma patients suffering from asthma and/or rhinitis participated in this study. All of them had positive skin prick tests and specific IgE antibodies to wheat flour. Control group consisted of 10 healthy subjects. Molecular identities of purified wheat allergens were characterized by using SDS-PAGE electrophoresis and tandem mass-spectrometry. Results: Allergen concentrations of 0.5 mg/ mL revealed that 12 patients reacted to alpha-amylase inhibitor, nine to peroxidase I, nine to thaumatin-like protein (TLP) and six to lipid transfer protein 2G (LTP2G). On the other hand, with the allergen concentration of 0.05 mg/mL five patients responded to alpha-amylase inhibitor, three to peroxidase I, four to LTP2G and six to TLP. TLP and LTP2G have not been earlier reported to be associated with baker‚s asthma. Conclusion: These results suggest that, in addition to earlier described alpha-amylase inhibitor protein and peroxidase I, TLP and LTP2G appear to be clinically important wheat allergens in baker‚s asthma. The role of these novel wheat allergens in respiratory disorders requires further studies.

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[120] - Panzani R, Armentia A, Lobo R, Postigo I, Martíinez J, Arranz ML, et al. Tolerance mechanisms in response to antigens responsible for baker's asthma in different exposed people. J Asthma 2008;45:333-338

BACKGROUND: Baker's asthma is among the most common occupational disease. The risk factors and immune features that may be important as predictors of tolerance or development of the disease are not completely understood. OBJECTIVE: To study the evolution over time of antigenic reactivity on baker's asthma in Spain and in France, in order to find differences in their allergenic response and evidence of protective or risks mechanisms against this disease. METHODS: Two groups of subjects were randomly selected. A group of bakers with asthma from Spain and a second group from France whose blood was taken 30 years ago: bakers with asthma, bakers without occupational respiratory allergy, and wives and children living close to the bakery. In all subjects skin tests were carried out with cereals, insects and the most common allergens in their area. Specific IgE, IgG(4) and IL 10 measurement were also determined. RESULTS: Spanish patients were mainly sensitized to cereal allergens and presented higher levels of IgE (p < 0.001). French patients are more often sensitised to insects than the Spanish ones: 5.26% versus 80% (p < 0.005). Symptom free or without aggravation at work subjects have higher specific IgG(4) and IL 10 levels than the others (p < 0.01). CONCLUSIONS: Antigens implicated in baker's asthma may change with time. The presence of higher levels of IgG(4), IL10 and diversity of sources of sensitisation in French patients may have helped them to develop a kind of natural hyposensitization.

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[121] - Hinojosa M. Occupational asthma in bakers: role of enzymes. Alergol Immunol Clin 2000;15:32-33

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[122] - Walusiak J, Krawczyk-Adamus P, Sander I, Zahradnik E, Raulf-Heimsoth M, Kobylinska A, et al. IgE binding to wheat and rye flour proteins in the sera of patients with baker's asthma. Allergy Clin Immunol Int 2005;17(Suppl. 1):387

Background: Allergy to wheat and rye flour accounts for the majority of cases of baker's asthma in Poland. Although the fact of the variability of IgE antibody patterns of flour sensitized bakers has been already known, there is no Polish data available. Therefore, the aim of the study was to investigate IgE binding to proteins of wheat and rye flour in subjects with occupational asthma due to these allergens. Matherial and methods: The study group comprised 11 bakers sensitized to wheat flour and 12 others allergic to rye flour. As controls, one serum from a baker without clinical symptoms and without specific IgE to any of the tested baker allergens and one serum of a not exposed patient were used. IgE antibodies to wheat and rye flour (f4, f5 from Pharmacia, Upsala, Sweden) were measured by using the Pharmacia CAP system. IgE-reactive proteins were identified by means of immunoblotting separately for water and ethanol soluble proteins of wheat and rye flour. Results: The IgE immunoblots presented a remarkable heterogeneity. Each patient showed an individual IgE-binding pattern with 2 to 40 different allergen spots. Sera of some patients reacted only with water soluble proteins, whereas of the others with ethanol soluble ones. None of the proteins bound to IgE in all patients. Conclusions: The results show a great interindividual variation of IgE-binding patterns of wheat and rye flour proteins in baker‚s asthma. There were not differences between findings concerning wheat and rye flour.

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[123] - Letrán A, Palacín A, Barranco P, Salcedo G, Pascual C, Quirce S. Rye flour allergens: An emerging role in baker's asthma. Am J Ind Med 2008;51:324-328

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[124] - Baur X, Posch A. Characterized allergens causing bakers' asthma. Allergy 1998;53:562-566

Although airborne allergens in bakeries and confectioneries cause one of the most common forms of occupational asthma, namely, bakers' asthma, only a few of them are known in detail so far. Here we summarize current knowledge of bakery allergens and describe our own two-dimensional (2-D) immunoelectrophoresis studies of wheat-flour allergens as well as the allergenic baking enzyme Asp o 2. Out of approximately 700 soluble wheat polypeptides, 70 show IgE binding; the following wheat-flour allergens could be identified and characterized: members of the alpha-amylase inhibitor family (14-18 kDa), acyl-CoA oxidase (26 kDa), peroxidase (36 kDa), and fructose-bisphosphate aldolase (37 kDa). However, the great majority of the soluble wheat-flour allergens, mainly located in the 27-, 55-, and 70-kDa areas of the 2-D immunoblots with pI values of 5.8-6.8, 5.9-6.5, and 5.5-6.1, respectively, are not known at present. Asp o 2, to which approximately 25% of all bakers with respiratory symptoms are sensitized, is a well-characterized starch-cleaving enzyme. We conclude that great effort is still needed to describe all major wheat-flour allergens. As shown by Asp o 2, knowledge of the causative allergens and their characteristics enables us to initiate very effective preventive measures such as the introduction of granulated allergenic products.

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[125] - Walusiak J, Krawczyk-Adamus P, Wiszniewska M, Dudek W, Niececierenko E, Palczynski C. Diagnostic value of specific IgE in baker's asthma and rhinitis due to wheat flour. Allergy Clin Immunol Int 2005;17(Suppl. 1):388

Background: The purpose of the study was to evaluate specificity, sensitivity and positive and negative predictive values (PPV, NPV) of allergen specific IgE in bakers with occupational bronchial allergy. Material and methods: The gold standard for the diagnosis of occupational asthma and/or rhinitis was specific inhalation challenge test. 231 bakers participated in the study. Occupational asthma due to wheat flour was recognized in 101 subjects, occupational rhinitis in 96 bakers and 106 patients were found not to have occupational allergy. 5 subjects with asthma due to alfa-amylase were excluded from the analysis. In all subjects SPT to common and occupational allergens, wheat, rye flour (f4, f5, fx20 from Pharmacia, Upsala, Sweden) and alfa-amylase specific IgE and histamine challenge test were performed. Results: In diagnosing baker's asthma the sensitivity of specific IgE was 60.4%, specificity 26.4%, PPV 68.5%, NPV 66.1%). In occupational rhinitis CAP RAST sensitivity was 76,5%, specificity 26.4%, PPV 31.7%, NPV 95.1%). All subjects sensitized to wheat flour were concurrently sensitized to rye proteins - differences between CAP RAST f4 and f5 results did not exceed one class. Moreover, significant correlation between the results of fx20 and f4/f5 results was found. Conclusions: The results support the thesis that specific inhalation challenge tests are needed when diagnosing bakers‚ asthma. The predictive value of the allergen specific IgE is not sufficient.

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[126] - Bittner C, Grassau B, Frenzel K, Baur X. Identification of wheat gliadins as an allergen family related to baker’s asthma. J Allergy Clin Immunol 2008;121:744-749

BACKGROUND: Flour is still one of the most common causes of occupational asthma worldwide. Thus far, little is known about the relevant allergens causing baker's asthma. Therefore the reliability of current diagnostic procedures is insufficient. Only few of the suspected causative wheat allergens have been hitherto characterized on the molecular level . OBJECTIVE: The aim was to identify and characterize unknown wheat allergens related to baker's asthma to improve the reliability of diagnostic procedures . METHODS: A wheat pJuFo cDNA phage display library was created and screened for IgE binding to wheat proteins with pooled sera from patients with baker's asthma. After identifying an alphabeta-gliadin, the frequency of sensitization was investigated by means of ELISA screening of 153 bakers' sera with the recombinant alphabeta-gliadin. Furthermore, the allergenicity of native total gliadin (alphabeta, gamma, omega) was analyzed by means of ImmunoCAP . RESULTS: One cDNA clone was identified as an alphabeta-gliadin. Serum IgE antibodies to the recombinant allergen were found in 12% of bakers with occupational asthma. Of the asthmatic bakers, 33% showed sensitization to native total gliadin; 4% of them had negative results on routine IgE testing with wheat extract . CONCLUSIONS: Gliadins represent a newly discovered family of inhalable allergens in baker's asthma. This finding demonstrates that water-insoluble proteins might also represent causative allergens.

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[127] - Fraj Lázaro J. Occupational respiratory allergy to alpha-amylase in bakers. Alergol Immunol Clin 2000;15:37-42

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[128] - Moreno-Ancillo A, Domínguez-Noche C, Gil-Adrados AC, Cosmes PM. Bread eating induced oral angioedema due to alpha-amylase allergy. J Investig Allergol Clin Immunol 2004;14:346-347

Inhalation of dust from different enzymes can be the cause of occupational asthma in exposed workers. Enzymes from different sources are being increasingly used in food. Few cases of food allergy to alpha-amylase induced by eating bread have been reported. Those cases were reported in bakery-related patients and in a pharmaceutical-industry worker. A 25-year-old farmer suffered sneezing, rhinorrhea, oropharyngeal itching, hoarseness, cough, and non-wheezy dyspnea after eating white bread. Skin prick tests (SPT) with common aeroallergens and food allergens revealed only sensitization to Olea europaea pollen. SPT response was positive to Aspergillus oryzae alpha-amylase. Specific IgE against alpha-amylase was positive. A double-blind placebo-controlled challenge with 5 mg of uncooked -amylase induced sneezing, cough, oral angioedema within 10 minutes. The provocation test with 50 g of white bread gave similar findings. This case indicates that alpha-amylase contained in bread may provoke IgE-mediated food allergy. It is worth noting that in this case, the only source of alpha-amylases sensitization was bread.

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[129] - Quirce S, Cuevas M, Diez-Gomez ML, Fernández-Rivas M, Hinojosa M, Gonzalez R, et al. Respiratory allergy to Aspergillus-derived enzymes in bakers' asthma. J Allergy Clin Immunol 1992;90:970-978

Baking and food industry workers are exposed to several powdered Aspergillus-derived enzymes with carbohydrate-cleaving activity that are commonly used to enhance baked products. We describe a retrospective study of sensitization to fungal alpha-amylase and cellulase on bakers. Five bakers in whom respiratory allergy symptoms developed when they were exposed to bread "improvers" that contained fungal alpha-amylase and cellulase were investigated by in vivo and in vitro tests. Type I hypersensitivity to these enzymes was demonstrated in the five patients by means of skin testing, histamine release test, positive reverse enzyme-immunoassay for specific IgE antibodies, and bronchial provocation test response to alpha-amylase or cellulase or both. Isolated immediate and dual responses to the bronchial challenge tests with these enzymes were observed. Immunoblot analysis with use of a pooled serum identified IgE-binding components in both enzymes. In the reverse-enzyme immunoassay-inhibition assays cross-reactivity between alpha-amylase and cellulase was not found, but some degree of cross-reactivity between alpha-amylase and A. oryzae, and between cellulase and A. niger was demonstrated. Four of the patients were also sensitized to cereal flour. Aspergillus-derived enzymes used as flour additives can elicit IgE-mediated respiratory allergy, and this fact has to be considered in the diagnosis and clinical management of bakers' asthma.

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[130] - Kanny G, Moneret-Vautrin DA. Alpha-amylase contained in bread can induce food allergy. J Allergy Clin Immunol 1995;95:132-133

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[131] - Baur X, Czuppon AB. Allergic reaction after eating alpha-amylase {Asp o 2)-containing bread. Allergy 1995;50:85-87

A 29-year-old female bakery shop assistant was occupationally sensitized to flour allergens and Aspergillus alpha-amylase (Asp o 2). The latter represents a strongly allergenic component of routinely used baking additives. The patient had repeatedly responded to the consumption of white bread with rhinitis, conjunctivitis, and, occasionally, wheal and flare reactions. She underwent allergologic investigations including oral challenge tests with commercially available bread loaves. Elevated specific IgE antibodies against bread extracts, Asp o 2, and flour allergens were detectable in her serum. The provocation test with bread resulted in a running nose together with a strong increase in nasal resistance. All symptoms subsided about 3 h after the challenge. None of the above symptoms could be observed when bread free of Aspergillus alpha-amylase was administered. This outcome provides evidence of a clinically relevant persistent allergenicity to Asp o 2 in bread.

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[132] - Poulsen LK. In-vitro diagnosis: serum-based methods used for risk assessment of allergenic food. Curr Opin Allergy Clin Immunol 2001;1:249-254

This review on in-vitro diagnostic methods focuses on the use of methods to perform risk assessment on foods. Based on the International Life Science Institute (ILSI) risk decision tree, the methods are discussed and three scenarios are suggested: (i) testing for a well-known allergen; (ii) testing for a well-known allergen, but with no previous history of food allergy; and (iii) testing for unknown allergens and cross-reactivity with known allergens.

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[133] - Moneret-Vautrin DA. Allergènes masqués: l'alpha amylase. Alim'Inter 2000;5(25):29-31

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[134] - Moreno-Ancillo A, Domínguez-Noche C, Gil-Adrados AC, Cosmes PM. Bread eating induced oral angioedema due to alpha-amylase allergy. J Investig Allergol Clin Immunol 2004;14:346-347

Inhalation of dust from different enzymes can be the cause of occupational asthma in exposed workers. Enzymes from different sources are being increasingly used in food. Few cases of food allergy to alpha-amylase induced by eating bread have been reported. Those cases were reported in bakery-related patients and in a pharmaceutical-industry worker. A 25-year-old farmer suffered sneezing, rhinorrhea, oropharyngeal itching, hoarseness, cough, and non-wheezy dyspnea after eating white bread. Skin prick tests (SPT) with common aeroallergens and food allergens revealed only sensitization to Olea europaea pollen. SPT response was positive to Aspergillus oryzae alpha-amylase. Specific IgE against alpha-amylase was positive. A double-blind placebo-controlled challenge with 5 mg of uncooked -amylase induced sneezing, cough, oral angioedema within 10 minutes. The provocation test with 50 g of white bread gave similar findings. This case indicates that alpha-amylase contained in bread may provoke IgE-mediated food allergy. It is worth noting that in this case, the only source of alpha-amylases sensitization was bread.

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[135] - Sander I, Raulf-Heimsoth M, Van Kampen V, Baur X. Is fungal alpha-amylase in bread an allergen ? Clin Exp Allergy 2000;30:560-565

BACKGROUND: The enzyme alpha-amylase from Aspergillus oryzae used in bakeries to improve the bread quality has been identified as an inhalative allergen in baker's asthma. It is doubtful whether this enzyme can induce allergic sensitization in regular bread consumers. OBJECTIVE: To find out whether fungal alpha-amylase in bread and rolls retains its antibody-binding capacity and allergenicity after the baking procedure. METHODS: Rabbit antibodies directed to fungal alpha-amylase were used for the development of a two-site enzyme-linked immunosorbent assay (ELISA). This assay was used to analyse different fractions of bread and rolls baked with the usual amounts of alpha-amylase in comparison with control products without added enzyme. Competitive experiments between bakers' sera containing specific immunoglobulin (Ig) E to alpha-amylase and the rabbit antibodies were performed. Additionally, specific IgE binding to fungal alpha-amylase was inhibited by native or heated alpha-amylase. RESULTS: With the highly specific two-site ELISA for native alpha-amylase in the crust of bread bottom and sides, 2.3-7 ng antigenic alpha-amylase per gram crust were measured. No alpha-amylase could be detected in the crumb fractions. Rabbit antibodies to native alpha-amylase completely inhibited human IgE binding to alpha-amylase allergen disks. CONCLUSION: The results prove residual antibody-binding capacity of alpha-amylase in bread crusts and in the crust of some rolls. In comparison with the content of alpha-amylase in dough, between 0.1 and 20% of the antibody-binding capacity remained.

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[136] - Blanco Carmona J. Immunochemical characteristics of alpha-amylase sensitization. Alergol Immunol Clin 2000;15:42-45

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[137] - Kanny G, Moneret-Vautrin DA. Alpha-amylase contained in bread can induce food allergy. J Allergy Clin Immunol 1995;95:132-133

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[138] - Sandiford CP, Tee RD, Newman Taylor AJ. The role of cereal and fungal amylases in cereal flour hypersensitivity. Clin Exp Allergy 1994;24:549-557

To investigate the role of cereal [alpha]- and [beta]-amylases in bakers' asthma, IgE responses of 30 wheat-flour-allergic individuals to barley [alpha]- and [beta]-amylases were compared with those to fungal [alpha]-amylase using radio allergosorbent test (RAST), RAST inhibition assays and Western blotting. RAST analyses showed that 29 of the 30 subjects with inhalant induced cereal allergy had positive IgE responses to cereal amylases, but only 16 responded positively to fungal [alpha]-amylase. Regression analysis showed an association between specific IgE to wheat flour and to barley [alpha]-amylase (r = 0.70) and barley [beta]-amylase (r = 0.92) but a poor association with fungal [alpha]-amylase (r = 0.34). RAST inhibition showed minimal crossreactivity between barley [alpha]- or [beta]-amylase and barley and fungal [alpha]-amylase. SDS-PAGE and Western blotting showed that non-reduced barley [alpha]-amylase had mol. wt. 54 kDa and barley [beta]-amylase mol. wt. 64 kDa; reduced fungal [alpha]-amylase had mol. wt. 54 kDa. It is concluded that cereal [alpha]- and [beta]-amylases are important allergens in patients with allergy to flour.

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[139] - Sander I, Raulf-Heimsoth M, Siethoff C, Lohaus C, Meyer HE, Baur X. Allergy to Aspergillus-derived enzymes in the baking industry: identification of beta-xylosidase from Aspergillus niger as a new allergen (Asp n 14). J Allergy Clin Immunol 1998;102:256-264

Aspergillus-derived enzymes are used in dough improvers in bakeries. Some of these enzymes are identified as causing IgE-mediated sensitization in up to 25% of bakers with workplace-related symptoms. OBJECTIVE: The aim of this study was to compare the frequency of sensitization to Aspergillus xylanase, cellulase, and glucoamylase with the sensitization to alpha-amylase (Asp o 2) and to identify IgE-reactive proteins in enzyme preparations. METHODS: Sensitization to Aspergillus-derived enzymes and cross-reactivity were retrospectively studied by enzyme allergosorbent test (EAST) and EAST-inhibition experiments. IgE-reactive proteins were detected by electrophoretic separation and immunoblotting. Liquid chromatography with electrospray ionization mass spectrometry and Edman degradation of tryptic protein fragments were used for the biochemical identification of an unknown IgE-binding protein. RESULTS: Twenty-three percent of 171 tested bakers had specific IgE to alpha-amylase, 8% reacted to glucoamylase, 13% reacted to cellulase, and 11% reacted to xylanase. Xylanase and cellulase preparations, each containing at least 6 different proteins, showed cross-reactivity in the range of 80%. The main IgE-binding protein in the xylanase preparation recognized in 7 of 8 xylanase-positive subjects was a protein of about 105 kd. This protein was identified as beta-xylosidase by peptide mass spectrometric fingerprinting. The identification was confirmed by matching 12 peptide sequences obtained by N-terminal and mass spectrometric sequencing to this protein. CONCLUSIONS: Beta-Xylosidase from Aspergillus niger is an occupational allergen present in currently used baking additives, which causes sensitization in at least 4% of symptomatic bakers. According to the International Union of Immunological Societies nomenclature, we suggest the term Asp n 14 for this allergen.

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[140] - Walusiak J, Krawczyk-Adamus P, Sander I, Zahradnik E, Raulf-Heimsoth M, Kobylinska A, et al. IgE binding to wheat and rye flour proteins in the sera of patients with baker's asthma. Allergy Clin Immunol Int 2005;17(Suppl. 1):387

Background: Allergy to wheat and rye flour accounts for the majority of cases of baker's asthma in Poland. Although the fact of the variability of IgE antibody patterns of flour sensitized bakers has been already known, there is no Polish data available. Therefore, the aim of the study was to investigate IgE binding to proteins of wheat and rye flour in subjects with occupational asthma due to these allergens. Matherial and methods: The study group comprised 11 bakers sensitized to wheat flour and 12 others allergic to rye flour. As controls, one serum from a baker without clinical symptoms and without specific IgE to any of the tested baker allergens and one serum of a not exposed patient were used. IgE antibodies to wheat and rye flour (f4, f5 from Pharmacia, Upsala, Sweden) were measured by using the Pharmacia CAP system. IgE-reactive proteins were identified by means of immunoblotting separately for water and ethanol soluble proteins of wheat and rye flour. Results: The IgE immunoblots presented a remarkable heterogeneity. Each patient showed an individual IgE-binding pattern with 2 to 40 different allergen spots. Sera of some patients reacted only with water soluble proteins, whereas of the others with ethanol soluble ones. None of the proteins bound to IgE in all patients. Conclusions: The results show a great interindividual variation of IgE-binding patterns of wheat and rye flour proteins in baker‚s asthma. There were not differences between findings concerning wheat and rye flour.

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[141] - Baur X, Sander I, Posch A, Raulf-Heimsoth M. Baker's asthma due to the enzyme xylanase: a new occupational allergen. Clin Exp Allergy 1998;28:1591-1593

The asthmatic baker showed IgE-mediated sensitization to xylanase of Aspergillus niger used as a baking additive. Inhalative challenge with approximately 0.5 microg of the enzyme resulted in an immediate-type asthmatic reaction. This case, as well as a preliminary screening of symptomatic bakers, shows that xylanase is a further relevant type I-sensitizer in the baking industry.

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[142] - Sander I, Raulf-Heimsoth M, Siethoff C, Lohaus C, Meyer HE, Baur X. Allergy to Aspergillus-derived enzymes in the baking industry: identification of beta-xylosidase from Aspergillus niger as a new allergen (Asp n 14). J Allergy Clin Immunol 1998;102:256-264

Aspergillus-derived enzymes are used in dough improvers in bakeries. Some of these enzymes are identified as causing IgE-mediated sensitization in up to 25% of bakers with workplace-related symptoms. OBJECTIVE: The aim of this study was to compare the frequency of sensitization to Aspergillus xylanase, cellulase, and glucoamylase with the sensitization to alpha-amylase (Asp o 2) and to identify IgE-reactive proteins in enzyme preparations. METHODS: Sensitization to Aspergillus-derived enzymes and cross-reactivity were retrospectively studied by enzyme allergosorbent test (EAST) and EAST-inhibition experiments. IgE-reactive proteins were detected by electrophoretic separation and immunoblotting. Liquid chromatography with electrospray ionization mass spectrometry and Edman degradation of tryptic protein fragments were used for the biochemical identification of an unknown IgE-binding protein. RESULTS: Twenty-three percent of 171 tested bakers had specific IgE to alpha-amylase, 8% reacted to glucoamylase, 13% reacted to cellulase, and 11% reacted to xylanase. Xylanase and cellulase preparations, each containing at least 6 different proteins, showed cross-reactivity in the range of 80%. The main IgE-binding protein in the xylanase preparation recognized in 7 of 8 xylanase-positive subjects was a protein of about 105 kd. This protein was identified as beta-xylosidase by peptide mass spectrometric fingerprinting. The identification was confirmed by matching 12 peptide sequences obtained by N-terminal and mass spectrometric sequencing to this protein. CONCLUSIONS: Beta-Xylosidase from Aspergillus niger is an occupational allergen present in currently used baking additives, which causes sensitization in at least 4% of symptomatic bakers. According to the International Union of Immunological Societies nomenclature, we suggest the term Asp n 14 for this allergen.

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[143] - Quirce S, Fernandez-Nieto M, Bartolome B, Bombin C, Cuevas M, Sastre J. Glucoamylase: another fungal enzyme associated with baker's asthma. Ann Allergy Asthma Immunol 2002;89:197-202

BACKGROUND: Aspergillus-derived enzymes are widely used as dough additives in the baking industry. These enzymes may give rise to immunoglobulin (Ig)E-mediated sensitization and occupational asthma. Glucoamylase (or amyloglucosidase) is an important industrial enzyme obtained from Aspergillus niger and used to provide fermentable sugars for yeast to improve loaf volume and texture. OBJECTIVE: The aim of our study was to investigate the potential allergenic role of glucoamylase in baker's asthma. METHODS: We report four subjects with work-related allergic respiratory symptoms who were exposed to glucoamylase and other starch-cleaving enzymes used as baking additives. The causative role of glucoamylase in work-related asthma was investigated by immunologic tests and specific inhalation challenges (SIC). Glucoamylase allergenic components were characterized by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and immunoblotting. RESULTS: Skin prick tests to glucoamylase (10 mg/mL) gave a positive response in all patients. Further, a positive skin prick test to alpha-amylase was obtained in the four patients and to hemicellulase in two of them. SIC to glucoamylase elicited isolated early asthmatic responses in the three patients tested, and SIC to alpha-amylase elicited early asthmatic responses in two patients and a dual asthmatic response in another patient. Immunoblotting with glucoamylase showed several IgE-binding bands with molecular masses between 33 and 96 kD. IgE-inhibition assays showed scarce to moderate allergenic cross-reactivity between glucoamylase and alpha-amylase. CONCLUSIONS: These bakers had developed IgE-mediated occupational asthma to glucoamylase and alpha-amylase. Fungal glucoamylase is widely used as a baking additive and this enzyme may give rise to allergic respiratory reactions among exposed workers.

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[144] - Merget R, Sander I, Raulf-Heimsoth M, Baur X. Baker's asthma due to xylanase and cellulase without sensitization to alpha-amylase and only weak sensitization to flour. Int Arch Allergy Immunol 2001;124:502-505

BACKGROUND: The baking additives xylanase and cellulase were described as baking additives causing baker's asthma. It is not known whether monosensitization to these enzymes may occur . METHODS: We present a case report of a baker with work-related asthma evaluated by skin prick test (SPT), enzyme-linked immunosorbent assay (EAST), immunoblot, EAST and immunoblot inhibition, and specific bronchial challenge. Fungal xylanase and alpha-amylase were measured by two-site enzyme immunoassays in products used by the patient at work . RESULTS: Allergy to xylanase and cellulase was demonstrated by SPT, EAST, immunoblot and specific bronchial challenge (for xylanase only). No sensitization to alpha-amylase could be demonstrated, but there was a weak flour allergy as documented by EAST and immunoblot and a positive occupational-type challenge with high concentrations of rye flour. Four baking additives contained measurable amounts of fungal alpha-amylase and xylanase, without a correlation between these enzymes . CONCLUSIONS: We conclude that occupational asthma due to the baking additives xylanase and cellulase may occur without concomitant sensitization to alpha-amylase and only weak sensitization to flour.

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[145] - Quirce S. Cross reactivity between enzymes. Alergol Immunol Clin 2000;15:50-52

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[146] - Day L, Augustin MA, Batey IL, Wrigley CW. Wheat-gluten uses and industry needs. Trends Food Sci Technol 2006;17:82-90

Gluten, the dough-forming protein of wheat flour, is the key to the unique ability of wheat to suit the production of leavened products. The past five decades have seen the rise of gluten as a commodity in its own right, through the large-scale industrial separation of wheat starch from gluten, plus the controlled drying of the gluten so as to retain its functional properties. The resulting Vital Dry Gluten is most widely used in bakery products. However, gluten (vital, de-vital or modified) is finding increasing use as a food ingredient to provide a range of functional properties at a more modest price than competitors such as milk and soy proteins.

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[147] - Fischer T. Effect of extrusion cooking on protein modification in wheat flour. Eur Food Res Technol 2004;218:128-132

Abstract Common soft wheat flour was extruded at three different temperatures and two different moistures. To investigate the dependence of the wheat protein modification on processing conditions, their solubilities in sodium dodecyl sulfate (SDS) were compared with those in SDS+(2-mercaptoethanol) ME. Furthermore, free sulfhydryl groups were detected with Ellmans Reagent and SDS-PAGE was performed under reducing and non-reducing conditions. The solubility values in SDS were greatly reduced after extrusion. The solubility values in SDS+ME were not affected. We therefore concluded that intermolecular cross-linking by disulfide bonding through extrusion cooking had occurred. This result was confirmed by SDS-PAGE under reducing and non-reducing conditions. At low and medium temperatures the solubilities were lower at low moisture; however, more free sulfhydryl groups were detected under these conditions, suggesting that moisture content of the flour has an influence on the way and the nature of the protein polymerization. At the highest thermal energy input at low moisture the solubilities increased again. This was accompanied by an increase of detectable free sulfhydryl groups. This led to the conclusion that disulfide bonds were cleaved at high energy input. The solubility development in 70% ethanol was nearly the same as in SDS. This is seen as a proof that gliadins are highly involved in the protein network formed under extrusion conditions. This finding was also confirmed by the results of SDS-PAGE.

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[148] - Pecquet C, Laurière M. Hydrolysats de protéines du blé: nouveaux allergènes. Rev Fr Allergol Immunol Clin 2003;43:21-23

Le blé est cultivé pour la farine qu'il produit. Le gluten constitué des protéines de réserve est valorisé sous forme native ou modifiée. L'hydrolyse de ces protéines permet leur solubilisation et leur valorisation du fait des propriétés émulsifiantes et stabilisatrices des émulsions qui en résulte. Ces protéines de blé hydrolysées sont donc utilisées dans l'industrie alimentaire et cosmétique. Des réactions allergiques ont été décrites récemment : urticaire de contact aux produits cosmétiques en contenant et réaction d'urticaire ou choc anaphylactique lors de l'ingestion d'aliments. Ces nouveaux allergènes sont donc à connaître.

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[149] - Kumagai H, Suda A, Sakurai H, Kumagai H, Arai S, Inomata N, et al. Improvement of digestibility, reduction in allergenicity, and induction of oral tolerance of wheat gliadin by deamidation. Biosci Biotechnol Biochem 2007;71:977-985

Wheat gliadin was deamidated by using a cation-exchange resin in the presence or absence of added cysteine, with the change in digestibility being measured. The allergenicity of the gliadin was evaluated by using sera from patients RAST-positive to wheat. Gliadin-specific IgE was measured after the gliadin had been orally administered to rats. The addition of cysteine before the treatment with a cation exchanger effectively increased the deamidation level of gliadin. Deamidated gliadin showed higher solubility than the undeamidated form. There was no difference in the peptic digestibility of the gliadin, whereas deamidation enhanced the pancreatic digestibility in vitro and the digestibility in the mouse stomach in vivo. Deamidation of gliadin reduced its reactivity toward the sera of patients with wheat allergy. Rats administered with deamidated gliadin showed suppressed elevation of the gliadin-specific IgE level.

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[150] - Wang JS, Zhao MM, Zhao QZ, Bao Y, Jiang YM. Characterization of hydrolysates derived from enzymatic hydrolysis of wheat gluten. J Food Sci 2007;72:C103-C107

The aim of this study is to investigate the characteristics of wheat gluten hydrolysates. Enzymatic hydrolysis was performed using a papain (food-grade enzyme) in the present study. The gluten proteins were hydrolyzed for 8 h. During enzymatic hydrolysis, average peptide chain length in the hydrolysate decreased rapidly. Increasing proteolysis resulted in the increase in the contents of the soluble forms of nitrogen. However, the content of peptide nitrogen increased within the 1st 6 h, and then began to decrease. The percentage of the released peptides with molecular weight (MW) of over 15 kD decreased with extending enzymatic hydrolysis, while those with MW below 5 kD increased significantly (P < 0.05). The peptides with MW 10 to 15 kD and those having the MW 5 to 10 kD had different changes. The polymeric glutenin and monomeric gliadin in gluten complex showed different behavior after enzymatic hydrolysis. The monomeric protein (gliadin) and soluble glutenin were prone to enzymatic hydrolysis, while insoluble glutenin was resistance to enzymatic hydrolysis.

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[151] - Moneret-Vautrin DA, Leduc V, Battais F, Morisset M, Beaudouin E, Croizier A, et al. Allergie aux isolats de farine de blé. Alim'Inter 2006;11:247-251

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[152] - Leduc V, Moneret-Vautrin DA, Guérin L, Morisset M, Kanny G. Anaphylaxis to wheat isolates: Immunochemical study of a case proved by means of double-blind, placebo-controlled food challenge. J Allergy Clin Immunol 2003;111:897-899

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[153] - Moneret-Vautrin DA, Morisset M, Leduc V, Battais F. Allergie exceptionnelle à la farine de blé s'étendant aux isolats. Alim'Inter 2006;11:253-255

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[154] - Mazé MH, Leduc V, Mouzita J, Denery-Papini S, Sergeant P, Moneret-Vautrin DA. Allergie aux isolats de farine de blé. Alim'Inter 2007;12:26-27

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[155] - Beaumont P, Leduc V, Battais F, Guérin L. Allergie à un isolat de blé contenu dans les pâtes alimentaires. Rev Fr Allergol Immunol Clin 2005;45:612-614

Les isolats de blé, néoallergènes alimentaires résultant de la désamidation du gluten et utilisés comme liants dans l'allergie alimentaire, particulièrement dans les produits de charcuterie, ont été responsables chez une patiente de réactions anaphylactiques après consommation de pâtes alimentaires. Leur responsabilité a été confirmée par la positivité des tests cutanés, la détection dans le sérum d'IgE anti-isolat de blé à forte concentration (20,1 KU/l, classe 4), puis détection et quantification de l'isolat de blé dans les pâtes par SDS-PAGE, immunoempreinte et Elisa inhibition.

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[156] - Moneret-Vautrin DA, Boulègue M, Leduc V, Morisset M, Denery-Papini S. Un cas exemplaire d'allergie à la farine de blé. Alim'Inter 2004;9:298-299

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[157] - Parisot L, Moneret-Vautrin DA. Réseau d'allergovigilance: évaluation des anaphylaxies sévères déclarées au 1er semestre 2006 comparativement aux années précédentes. Alim'Inter 2006;11:233-235

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[158] - Pecquet C, Lauriere M, Huet S, Leynadier F. Is the application of cosmetics containing protein-derived products safe ? Contact Dermatitis 2002;46:123

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[159] - Laurière M, Pecquet C, Bouchez-Mahiout I, Snégaroff J, Bayrou O, Raison-Peyron N, et al. Hydrolysed wheat proteins present in cosmetics can induce immediate hypersensitivities. Contact Dermatitis 2006;54:283-289

Cosmetics containing hydrolysed wheat proteins (HWP) can induce rare but severe allergic reactions. 9 patients, all females without common wheat allergy, but with contact urticaria to such cosmetics, were studied. 6 of them also experienced generalized urticaria or anaphylaxis to foods containing HWP. All patients had low to moderate levels of immunoglobulin (Ig)E specific of wheat flour (f4) or gluten (f79). Their sensitivity to HWP and their tolerance to unmodified wheat proteins extracted from grains were confirmed using skin tests. Immunoblotting analyses showed that IgE from all patients reacted with almost all HWP tested. Reactions generally occurred with large random peptide aggregates. IgE reacted also with unmodified grain proteins, which contrasted with skin tests results. They reacted always with salt soluble proteins but variably with gluten proteins. No reaction occurred with gliadins in patients without associated immediate hypersensitivity to food containing HWP. These results show the role of hydrolysis on the allergenicity of wheat proteins, both through skin or digestive routes. At least part of the epitopes involved is pre-existing in unmodified wheat proteins. The aggregation of peptide bearing these epitopes and others created by hydrolysis, along with the increased solubility and the route of exposure, are possible factors of the allergenicity of HWP.

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[160] - Denery-Papini S, Lauriere M, Branlard G, Morisset M, Pecquet C, Choudat D, et al. Influence of the Allelic Variants Encoded at the Gli-B1 Locus, Responsible for a Major Allergen of Wheat, on IgE Reactivity for Patients Suffering from Food Allergy to Wheat. J Agric Food Chem 2007;55:799-805

Wheat presents an important genetic diversity that could be useful to look for cultivars with reduced allergencity. omega5-Gliadins have been described as major allergens for wheat allergic patients suffering from wheat-dependent exercise-induced anaphylaxis (WDEIA) and some cases of chronic urticaria (U). Our objective was to study the influence of genetic variability at the Gli-B1 locus encoding for omega5-gliadins on the reactivity of IgE antibodies from these patients. We selected cultivars expressing 13 alleles at Gli-B1 including a wheat/rye translocation and studied the reactivity to gliadins of a rabbit antiserum specific for omega5-gliadins and of IgE from 10 patients. The antiserum and IgE from nine patients with WDEIA and U strongly detected omega5-gliadins expressed by most of the Gli-B1 alleles but showed no or faint responses to the gliadins and secalins extracted from the translocated wheat. The selection of genotypes lacking the Gli-B1 locus may reduce wheat allergenicity. Keywords: Wheat; food allergy; exercise induced anaphylaxis; omega5-gliadins; allelic variants.

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[161] - Bouchez-Mahiout I, Snégaroff J, Boulenc E, Pecquet C, Choudat D, Raison-Peyron N, et al. Spécificité des protéines impliquées dans différentes formes d’allergie au blé. Rev Fr Allergol Immunol Clin 2007;47:285

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[162] - Laurière M, Pecquet C, Bouchez-Mahiout I, Snégaroff J, Bayrou O, Raison-Peyron N, et al. Hydrolysed wheat proteins present in cosmetics can induce immediate hypersensitivities. Contact Dermatitis 2006;54:283-289

Cosmetics containing hydrolysed wheat proteins (HWP) can induce rare but severe allergic reactions. 9 patients, all females without common wheat allergy, but with contact urticaria to such cosmetics, were studied. 6 of them also experienced generalized urticaria or anaphylaxis to foods containing HWP. All patients had low to moderate levels of immunoglobulin (Ig)E specific of wheat flour (f4) or gluten (f79). Their sensitivity to HWP and their tolerance to unmodified wheat proteins extracted from grains were confirmed using skin tests. Immunoblotting analyses showed that IgE from all patients reacted with almost all HWP tested. Reactions generally occurred with large random peptide aggregates. IgE reacted also with unmodified grain proteins, which contrasted with skin tests results. They reacted always with salt soluble proteins but variably with gluten proteins. No reaction occurred with gliadins in patients without associated immediate hypersensitivity to food containing HWP. These results show the role of hydrolysis on the allergenicity of wheat proteins, both through skin or digestive routes. At least part of the epitopes involved is pre-existing in unmodified wheat proteins. The aggregation of peptide bearing these epitopes and others created by hydrolysis, along with the increased solubility and the route of exposure, are possible factors of the allergenicity of HWP.

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[163] - Snégaroff J, Bouchez-Mahiout I, Pecquet C, Choudat D, Raison-Peyron N, Vigan M, et al. Des protéines recombinantes pour tester in vitro la réactivité des IgE de patients allergiques au blé. Rev Fr Allergol Immunol Clin 2007;47:266-267

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[164] - Snégaroff J, Branlard G, Bouchez-Mahiout I, Laudet B, Tylichova M, Chardot T, et al. Recombinant Proteins and Peptides as Tools for Studying IgE Reactivity with Low-Molecular-Weight Glutenin Subunits in Some Wheat Allergies. J Agric Food Chem 2007;55:9837-9845

Two genes of wheat low-molecular-weight glutenin subunits (LMW-GS), B16 and P73, were cloned and expressed in E. coli. They were homologous to proteins encoded respectively at Glu-B3 and Glu-D3 loci. The N-terminal and C-terminal halves of B16 (NB16 and B16C) and the two chimeras combining the halves of the two genes (B16-P73 and P73- B16) were also expressed. All these constructs were compared for their reactivity with IgE from 24 patients suffering from different forms of wheat allergies. The results confirmed that LMW-GSs bound IgE in all adult allergies tested. Strong differences in reactivity between all the constructs were observed. They were disease-dependent. In wheat-dependent exercise-induced anaphylaxis (WDEIA), the reactivity of the constructs depended partly on common epitopes with omega-5 gliadins but also on differences in molecule conformation. The presence of NB16 in the constructs greatly influenced their IgE reactivity.

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[165] - Akiyama H, Sakata K, Yoshioka Y, Murata Y, Ishihara Y, Teshima R, et al. Profile Analysis and Immunoglobulin E Reactivity of Wheat Protein Hydrolysates. Int Arch Allergy Immunol 2006;140:36-42

BACKGROUND: Wheat protein hydrolysates have been traditionally used as food additives and are now being used in cooking worldwide. There have been a few studies on the relationship between the molecular mass distribution and the immunoglobulin E (IgE) reactivity of the wheat protein hydrolysates . METHOD: We analyzed the peptide profile of commercial wheat protein hydrolysate samples from enzymatic or acid hydrolysis of wheat protein using size exclusion chromatography. We further investigated the IgE reactivity of the wheat protein hydrolysates using the inhibition ELISA method and sera of 5 patients sensitive to wheat . RESULTS: The wheat protein enzymatic hydrolysate samples showed high concentrations of peptides with molecular masses greater than 1,050 Da, whereas in contrast, the wheat protein acid hydrolysates showed extremely low concentrations of peptides with molecular masses greater than 1,050 Da. Tested wheat protein acid hydrolysates hardly inhibited the patient IgE binding ability to wheat proteins in the five patient sera. On the contrary, some tested wheat protein enzymatic hydrolysate samples inhibited the IgE binding ability to wheat proteins . CONCLUSION: These results suggested that the uptake of wheat protein enzymatic hydrolysates might still have the possibility of causing food allergic reactions in patients allergic to wheat and the processed foods containing them

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[166] - Corominas M, Lleonart R, Martin C, De la Torre F. Profile of allergen pollen reactivity in patients sensitised to Olea pollen. Allergy 2008;63(suppl. 88):104

Background: Previous studies performed in our area (with low levels of Olea pollen) showed that 38% of patients with pollinosis were sensitised to Olea, although only 7% of them are monosensitised. The aim of this study is to evaluate sensitisation to olive pollen as a consequence of cross reactivity with other pollen allergens. We studied the sensitisation pollen profile of patients with positive skin prick test (SPT) to Olea and the cross reactivity with other pollen allergens. Patients and methods: Fourteen adult patients (8 males and 6 females) whith a positive SPT to Olea pollen were included. We analyzed their clinical history and SPT to common airborne allergens and allergens with a high LTP, profilin or polcalcin content. Specific serum IgE against to recombinant allergens Ole e1, Ole e 9, Salk1, Par j 1, Phl p 1, Phl p 5, Art v 1, Cup s 1, Bet v 1, Pru p 3, Mal d 4, Che a 3 (ALK-Abello) were quantified in the ADVIA Centaur platform. Results: Ten patients presented rhinitis and four asthma and rhinitis. According to SPT, 78% were positive to grasses, 64% to Parietaria, 57% to Salsola, 57% to Plantago, 50% to Platanus, 43% to Artemisia, 36% to Cupressus, 36% to peach, 21% to polcalcin, 14% to profilin and 14% to Betula. When we analyzed specific IgE against recombinant allergens, we found that 11 of the 14 patients (78%) were reactive to Ole e1 and none to Ole e 9. Only one patient had specific IgE to Che a 3 (polcalcin), and another to Che a 3 and to Mal d 4 (profilin). Ole e 1 specific IgE levels correlated with IgE levels of Phl p 1, Phl p 5, Pru p 3, Cup s 1, Che a 3, Mal d4, Pla l 1 and Bet v 1 (P<0.002). Conclusions: Most of the patients sensitised to Olea had specific IgE to Ole e 1 allergen. Profilin and polcalcin allergens are not responsible for polysensitisation present in these patients. In this group, sensitisation to Olea pollen corresponds to the great number of sensitisation present, but it is not a result of cross reactivity.

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[167] - Larré C, Denery-Papini S, Popineau Y, Deshayes G, Desserme C, Lefebvre J. Biochemical Analysis and Rheological Properties of Gluten Modified by Transglutaminase. Cereal Chem 2000;77:121-127

A transglutaminase from Streptoverticillium sp. was used to create new covalent intermolecular cross-links between proteins in gluten. This modification induced drastic changes in its physicochemical properties as well as in its rheological behavior. To understand these changes, we characterized the gluten extractability in acetic acid and identified the proteins of supernatant and pellet by immunoblotting using antibodies specific for each prolamin class. The proportion of soluble proteins decreased drastically after transglutaminase treatment due to the formation of large insoluble polymers as shown by SDS-PAGE. Among the constitutive proteins of gluten, the high molecular weight glutenin subunits were the most affected in the transglutaminase reaction. The rheological behavior of gluten after 18 hr of incubation with transglutaminase was studied in shear by dynamic measurements over 10-3 ˆ 101 Hz frequency range and by creep and recovery tests. The behavior of treated glutens remained that of a transient network, but the viscoelastic response was shifted toward shorter times and the steady-state viscosity was greatly increased. The enzymatic treatment caused a considerable reinforcement of the network. The modified glutens were also less sensitive to thermal processing than unmodified glutens, as shown by a lower amplitude of variation of storage modulus G' with temperature after enzymatic treatment.

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[168] - Malandain H. Transglutaminases : a meeting point for wheat allergy, celiac disease, and food safety. Eur Ann Allergy Clin Immunol 2005;37:397-403

Wheat is the staple cereal in many countries and its uses in manufactured foods are ever growing due to the technological qualities of gluten proteins. Transglutaminases (TG) are ubiquitous enzymes with many functions. They are able to transform proteins by deamidation and/or transamidation. This last reaction can cross-link proteins together. Intestinal tissue TG has been shown to play an important role in two kinds of immune reactions to wheat: celiac disease and wheat-dependent exercise-induced anaphylaxis. In addition, new epitopes have been suspected in cases of anaphylaxis to wheat isolates, a food ingredient consisting mainly of deamidated gluten proteins. As a microbial TG is included in many food technological processes, its safe use should be checked. This assessment must cover not only the safety of the TG itself but also that of the deamidated/cross-linked proteins generated by this enzyme. This article aims at discussing the possible consequences of using TG in food industry in the light of today knowledge about immune reactions to wheat.

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[169] - Morita E, Kunie K, Matsuo H. Food-dependent exercise-induced anaphylaxis. J Dermatol Sci 2007;47:109-117

Food-dependent exercise induced anaphylaxis (FDEIA) is a distinct form of food allergy induced by physical exercise. Symptoms are typically generalized urticaria and severe allergic reactions such as shock or hypotension. Whereas various food items are responsible for the development of FDEIA, wheat is reported to be the allergen with the highest frequency in Japan. Recently aspirin has been known to be an additional exacerbating factor. Skin tests and in vitro serum food-specific IgE assays are currently used, however their sensitivity and specificity are not always satisfactory. A challenge test consisting of ingestion of assumed food followed by intense physical exercise is the only reliable method to determine the causative food and to diagnose the disease. The challenge test is not always safe because in some cases the test induces an anaphylactic shock. So a reliable in vitro diagnostic method is necessary for the patients with FDEIA. We revealed that wheat omega-5 gliadin and high molecular weight gl utenin subunit are major allergens in wheat-dependent exercise-induced anaphylaxis (WDEIA). A simultaneous detection of specific IgE to epitope sequences of both omega-5 gliadin and high molecular weight glutenin is found to achieve higher sensitivity and specificity compared with the in vitro serum food-specific IgE assays currently used for diagnosis of WDEIA. On the other hand, immunoreactive gliadins appeared in the sera of patients during the provocation test with both wheat-exercise and wheat-aspirin challenges in parallel with allergic symptoms. These findings suggest that FDEIA is IgE-mediated hypersensitivity reaction to foods and both exercise and aspirin facilitate allergen absorption from the gastrointestinal tract.

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[170] - Palosuo K, Varjonen E, Nurkkala J, Kalkkinen N, Harvima R, Reunala T, et al. Transglutaminase-mediated cross-linking of a peptic fraction of omega-5 gliadin enhances IgE reactivity in wheat-dependent, exercise-induced anaphylaxis. J Allergy Clin Immunol 2003;111:1386-1392

BACKGROUND: Patients with wheat-dependent, exercise-induced anaphylaxis (WDEIA) experience recurrent anaphylactic reactions when exercising after ingestion of wheat products. We have identified omega-5 gliadin (Tri a 19) as a major allergen in WDEIA, but the role of exercise in eliciting the symptoms remains obscure . OBJECTIVE: The aim was to examine whether tissue transglutaminase (tTG)-mediated cross-linking could be involved in modulating the IgE-binding ability and in vivo reactivity of digested omega-5 gliadin peptides in WDEIA . METHODS: Purified omega-5 gliadin was digested with pepsin or with pepsin and trypsin and treated with tTG. The binding of IgE antibodies in pooled sera from 10 patients with WDEIA was studied by means of immunoblotting before and after tTG treatment of the digested peptides. The peptides derived from pepsin digestion were separated by means of gel-filtration chromatography, and IgE reactivity of 4 different peptide fractions was studied by immunoblotting before and after tTG treatment. The fraction showing the greatest degree of cross-linking by tTG was further studied by means of IgE ELISA, ELISA inhibition, and skin prick testing . RESULTS: The IgE-binding ability of omega-5 gliadin was retained after pepsin and pepsin-trypsin digestion. tTG treatment of the whole peptic digest formed large peptide complexes, with molecular weights ranging from 40 to greater than 200 kd. These cross-linked aggregates bound IgE antibodies in immunoblotting more intensely than untreated, pepsin-digested, or pepsin-trypsin-digested omega-5 gliadin. A gel-filtration fraction of the whole peptic digest corresponding to the highest peak of the chromatogram and showing the greatest degree of tTG-mediated cross-linking showed an increase in serum IgE reactivity in ELISA after tTG treatment, as well as a shift of reactivity to cross-linked complexes. In the 20 patients with WDEIA, the mean skin prick test wheal elicited by this tTG-treated peptic fraction was 77% larger (P <.001) than that elicited by the untreated peptic fraction and 56% larger (P <.01) than that elicited by intact omega-5 gliadin . CONCLUSIONS: Omega-5 gliadin-derived peptides are cross-linked by tTG, which causes a marked increase in IgE binding both in vitro and in vivo. Activation of tTG during exercise in the intestinal mucosa of patients with WDEIA could lead to the formation of large allergen complexes capable of eliciting anaphylactic reactions.

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[171] - Bouchez-Mahiout I, Snégaroff J, Boulenc E, Pecquet C, Choudat D, Raison-Peyron N, et al. Spécificité des protéines impliquées dans différentes formes d’allergie au blé. Rev Fr Allergol Immunol Clin 2007;47:285

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[172] - Bouchez-Mahiout I, Tylichova M, Snégaroff J, Pecquet C, Branlard G, Laurière M. Diversité de la réactivité des IgE vis à vis des protéines du blé dans l'anaphylaxie au blé induite par l'effort. Rev Fr Allergol Immunol Clin 2008;48:275

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[173] - Battais F, Courcoux P, Popineau Y, Kanny G, Moneret-Vautrin DA, Denery-Papini S. Food allergy to wheat: differences in IgE binding proteins as a function of age and symptoms. J Cereal Sci 2005;42:109-117

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[174] - Morita E, Matsuo H, Mihara S, Morimoto K, Savage AW, Tatham AS. Fast omega-gliadin is a major allergen in wheat-dependent exercise-induced anaphylaxis. J Dermatol Sci 2003;33:99-104

BACKGROUND: Wheat-dependent exercise-induced anaphylaxis is an anaphylaxy induced by physical exercise after ingestion of wheat. An immediate-type hypersensitivity to water/salt-insoluble fraction of wheat proteins (gluten) has been considered to underlie in this disease. OBJECTIVE: The aim of the study is to determine the major allergen in Japanese patients with wheat-dependent exercise-induced anaphylaxis by using a panel of purified wheat gliadins and glutenins. METHODS: Water/salt-insoluble wheat proteins, alpha-gliadin, beta-gliadin, gamma-gliadin, fast omega-gliadin, slow omega-gliadin, high molecular weight glutenin and low molecular weight glutenin, were purified, and five patients with wheat-dependent exercise-induced anaphylaxis, whose diagnose had been determined by positive-challenge test, were evaluated for skin prick test, dot-blotting test and CAP-RAST inhibition test by using these purified wheat proteins. RESULTS: The fast omega-gliadin was the most potent allergen among these water/salt-insoluble proteins when evaluated by skin prick test and dot-blotting test. Fast and slow omega-gliadin, and gamma-gliadin caused dose-dependent inhibition of the serum IgE-binding to solid-phase gluten in the patients. The incubation with fast omega-gliadin of the patient's serum caused dose-dependent inhibition in the IgE-binding to gamma-gliadin as well as slow omega-gliadin, indicating a cross-reactivity of these proteins in IgE-binding. CONCLUSION: We concluded that fast omega-gliadin is a major allergen among these water/salt-insoluble proteins for wheat-dependent exercise-induced anaphylaxis in Japanese patients, and IgE against fast omega-gliadin cross-reacts to gamma-gliadin and slow omega-gliadin.

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[175] - Matsuo H, Dahlstrom J, Tanaka A, Kohno K, Takahashi H, Furumura M, et al. Sensitivity and specificity of recombinant omega-5 gliadin-specific IgE measurement for the diagnosis of wheat-dependent exercise-induced anaphylaxis. Allergy 2008;63:233-236

BACKGROUND: A recent study has shown that the measurement of specific IgE antibodies to B-cell epitope peptides of wheat omega-5 gliadin (Pep A) and high molecular weight glutenin subunit (Pep B) are useful to diagnose wheat-dependent exercise-induced anaphylaxis (WDEIA). AIMS OF THE STUDY: We sought to compare the sensitivity and specificity of the in vitro tests for measuring the specific IgE antibodies to recombinant omega-5 gliadin (romega-5 gliadin) with those for wheat, gluten, Pep A, and Pep B in identification of patients with WDEIA . METHODS: Fifty patients with WDEIA, 25 healthy subjects and 25 patients with atopic dermatitis with specific IgE antibodies to wheat but without experience of allergic reactions after ingestion of wheat products were enrolled in this study. The concentrations of specific IgE antibodies were measured using ImmunoCAP. The empirical receiver operating characteristics curves (ROC) for each test were prepared and the areas under the ROC curve (AUC) were compared . RESULTS: In patients with WDEIA, the sensitivities of the allergen-specific IgE tests for wheat, gluten, Pep A, Pep B and romega-5 gliadin were 48%, 56%, 76%, 22%, and 80%, respectively. The seven of 10 WDEIA patients with no specific IgE antibodies to romega-5 gliadin had specific IgE antibodies to Pep B. The highest AUC (0.850) was observed in the test for romega-5 gliadin . CONCLUSIONS: Measuring the concentration of specific IgE antibodies to romega-5 gliadin is more useful than to wheat, gluten, or Pep A in the identification of patients with WDEIA.

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[176] - Malandain H. Transglutaminases : a meeting point for wheat allergy, celiac disease, and food safety. Eur Ann Allergy Clin Immunol 2005;37:397-403

Wheat is the staple cereal in many countries and its uses in manufactured foods are ever growing due to the technological qualities of gluten proteins. Transglutaminases (TG) are ubiquitous enzymes with many functions. They are able to transform proteins by deamidation and/or transamidation. This last reaction can cross-link proteins together. Intestinal tissue TG has been shown to play an important role in two kinds of immune reactions to wheat: celiac disease and wheat-dependent exercise-induced anaphylaxis. In addition, new epitopes have been suspected in cases of anaphylaxis to wheat isolates, a food ingredient consisting mainly of deamidated gluten proteins. As a microbial TG is included in many food technological processes, its safe use should be checked. This assessment must cover not only the safety of the TG itself but also that of the deamidated/cross-linked proteins generated by this enzyme. This article aims at discussing the possible consequences of using TG in food industry in the light of today knowledge about immune reactions to wheat.

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[177] - Palosuo K, Varjonen E, Alenius H, Reunala T. Clinical and laboratory findings in 32 patients with wheat-dependent, exercise-induced anaphylaxis. EAACI 22th Congress, Paris, 7-11 June, 2003, Poster n°29

Wheat has been increasingly recognized as a cause of food-dependent, exercise-induced anaphylaxis. This is a unique form of allergy, where ingestion of a specific food before physical exercise triggers anaphylactic reactions. We examined a total of 32 patients (13 females, 19 males) with wheat-dependent, exercise-induced anaphylaxis (WDEIA). All patients had positive skin prick test responses to wheat (1:10 w/v) and crude gliadin (1 mg/ml). In addition, the patients showed positive skin prick test responses or specific IgE antibodies in ELISA to purified omega-5 gliadin (Tri a 19), a major allergen in WDEIA. None of the patients had suffered from wheat allergy in childhood, and other atopic diseases, such as allergic rhinitis, atopic dermatitis, or asthma were present in 30% of the patients. The mean age at onset of WDEIA was 34 years (range 18 to 66 years) and at diagnosis 40 years (range 24 to 77 years). The amount of wheat ingested as well as the degree of exercise needed to provoke symptoms showed considerable variation. The foods most typically triggering symptoms included bread, pasta, pizza, and pastries. The level of physical exertion ranged from light indoor activities and walking to more strenuous exercise, such as bicycling, jogging, skiing, dancing, and ball games. The time between wheat ingestion and the beginning of exercise varied from 10 minutes to 4 hours, and the duration of exercise before the onset of symptoms from 10 minutes to about 1 hour. The prodromal symptoms included pruritus, flushing, and erythema of the skin. This was followed by generalized urticaria in all patients. In 21 (66%) patients it was accompanied by angioedema and in seven (22%) patients by respiratory distress. Hypotension was documented in 20 (63%) patients, and 8 (25%) patients reported dizziness (blood pressure not taken). The reaction progressed to vascular collapse in 24 (75%) patients. The number of anaphylactic episodes ranged from one to ten per year. Introduction of a gluten-free or wheat-free diet led to symptom resolution, and the patients were able to continue their earlier exercise regimens. The present material suggests that the prevalence of WDEIA is higher than generally believed. Skin prick testing with wheat gliadin and detection of IgE to omega-5 gliadin with ELISA facilitates the diagnosis of this severe allergy.

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[178] - Fiedler EM, Zuberbier T, Worm M. A combination of wheat flour, ethanol and food additives inducing FDEIA. Allergy 2002;57:1090-1091

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[179] - Aihara Y, Kotoyori T, Takahashi Y, Osuna H, Ohnuma S, Ikezawa Z. The necessity for dual food intake to provoke food-dependent exercise-induced anaphylaxis (FEIAn): a case report of FEIAn with simultaneous intake of wheat and umeboshi. J Allergy Clin Immunol 2001;107:1100-1105

BACKGROUND: Food-dependent exercised-induced anaphylaxis (FEIAn) is classified among the physical allergies. Many different food allergens have been reported, but the pathophysiology of FEIAn remains unknown. Furthermore, provocation tests with a suspected food do not always succeed in patients with FEIAn. OBJECTIVE: We sought to clarify and investigate causative foods and mechanisms of FEIAn in a 14-year-old boy. In addition, we tested in vivo and in vitro effects of cromolyn sodium in the same patient. METHODS: We used open challenge tests for the provocation of FEIAn and measured changes in plasma histamine levels and FEV1. In addition, we investigated the mechanism of FEIAn in this case with in vitro histamine release testing. RESULTS: The patient was diagnosed as having FEIAn by provocation testing with a simultaneous intake of wheat and umeboshi, but not when each food was eaten singly, followed by exercise. In addition, his plasma histamine level increased transiently and forced expiratory volume 1, expressed as a percentage change from baseline, decreased significantly. A synergistic effect on in vitro histamine release testing with 2 kinds of the causative foods was shown. Administration of cromolyn sodium proved to be effective on both the in vitro and in vivo tests. CONCLUSION: This is the first report of FEIAn provoked by the test with a simultaneous intake of 2 kinds of food. This case might in part explain negative challenge test results in patients with FEIAn

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[180] - Sowa J, Tomitaka A, Suzuki K, Matsunaga K. [A case of food-dependent exercise-induced anaphylaxis (FDEIA) caused by wheat successfully induced by administration of aspirin and wheat]. Arerugi 2001;50:547-550

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[181] - Fujita H, Osuna H, Kanbara T, Inomata N, Ikezawa Z. [Wheat anaphylaxis enhanced by administration of acetylsalicylic acid or by exercise]. Arerugi 2005;54:1203-1207

A 23-year-old woman experienced generalized urticaria and loss of consciousness during walking after ingestion of wheat. Skin prick test and CAP-RAST were positive for gluten. An oral challenge test using 100g wheat was positive without exercise. The patient was given diagnosis of wheat allergy. In addition, not only exercise but also administration of 500mg aspirin were found to exacerbate her symptoms after the ingestion of wheat, suggesting that acetylsalicylic acid could be an augmentation factor in wheat allergy. Etodorac failed to enhance the symptoms. Further, oral administration of Fexofenadine could prevent allergic reactions induced by ingestion of 100g wheat, but sodium cromoglycate partially reduced the reactions.

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[182] - Nakamura K, Inomata N, Ikezawa Z. Dramatic augmentation of wheat allergy by aspirin in a dose-dependent manner. Ann Allergy Asthma Immunol 2006;97:712-713

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[183] - Le Corre Y, Drouet M, Nicolie B, Bonneau JC, Leclère JM, Beauvillain C. Anaphylaxie induite par l'exercice au blé (AIE-blé): rôle du Saccharomyces ? Rev Fr Allergol Immunol Clin 2008;48:274

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[184] - Rasmussen SW. Sequence of a 28.6 kb region of yeast chromosome XI includes the FBA1 and TOA2 genes, an ORF similar to a TCTP, one ORF containing motifs also found in plant storage proteins and 13 ORFs with weak or no homology to known proteins. Yeast 1994;10:S63-S68

The complete DNA sequence of cosmid clone pUKG148 comprising 28,600 base pairs was determined from an ordered set of subclones. The sequence contains 22 open reading frames longer than 100 amino acids of which five are entirely covered by other, longer reading frames. YKL054 exhibits 25% homology at the amino acid level to a number of plant storage proteins of the glutenin type, YKL056 is 40% homologous to a translationally controlled mammalian tumour protein, YKL058 (TOA2) is identical to the small subunit of transcription factor TFIIA from yeast and YKL060 is identical to the FBA1 gene also from yeast, already sequenced but not mapped to chromosome XI. The remaining 13 open reading frames show weak or no homology to known genes.

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[185] - Tanabe S. Analysis of Food Allergen Structures and Development of Foods for Allergic Patients. Biosci Biotechnol Biochem 2008;72:649-659

Food allergy is one of the important health problems, and countermeasures are socially required. We have been undertaking studies on wheat allergens and their epitopes, and have developed a method for producing hypoallergenic wheat flour by enzymatic modification. The hypoallergenic products are now provided to patients. More noteworthy, by taking hypoallergenic cupcakes over a long period, more than half of patients are hyposensitized and become able to eat normal wheat products. This suggests that the hypoallergenic wheat flour can act as anti-allergenic via allergen-specific immunotolerance.This series of studies was followed by expansive research on food allergy: analysis of epitopes of bovine serum albumin (the major beef allergen), isolation and identification of inhibitory peptides for allergen absorption at the intestine, evaluation of hesperetin as an inhibitor of degranulation of mast cells, and the development of PCR detection methods for verifying allergen labeling and for identifying hidden allergic ingredients in processed foods.

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[186] - Sampson HA, Ho DG. Relationship between food-specific IgE concentrations and the risk of positive food challenges in children and adolescents. J Allergy Clin Immunol 1997;100:444-451

"BACKGROUND: The double-blind, placebo-controlled food challenge (DBPCFC) is the ""gold standard"" for diagnosis of food hypersensitivity. Skin prick tests and RASTs are sensitive indicators of food-specific IgE antibodies but poor predictors of clinical reactivity. Previous studies suggested that high concentrations of food-specific IgE antibody were predictive of food-induced clinical symptoms. Because the CAP System FEIA (Pharmacia Diagnostics, Uppsala, Sweden) provides a quantitative assessment of allergen-specific IgE antibody, this study was undertaken to determine the potential utility of the CAP System FEIA in diagnosis of IgE-mediated food hypersensitivity . METHODS: Sera from 196 patients with food allergy were analyzed for specific IgE antibodies to egg, milk, peanut, soy, wheat, and fish by CAP System FEIA. Sera were randomly selected from 300 stored samples of children and adolescents who had been evaluated by history, skin prick tests, and DBPCFCs. The study population was highly atopic; all patients had atopic dermatitis, and approximately 50% had asthma and allergic rhinitis at the time of initial evaluation. The performance characteristics of the CAP System FEIA were compared with those of skin prick tests and the outcome of DBPCFCs or ""convincing"" histories of anaphylactic reactions . RESULTS: The prevalence of specific food allergies in the study population varied from 22% for wheat to 73% for egg. Allergy to egg, milk, peanut, and soy accounted for 87% of confirmed reactions. The performance characteristics of skin prick tests and CAP System FEIA (egg, milk, peanut, fish) were comparable, with excellent sensitivity and negative predictive accuracy but poor specificity and positive predictive accuracy. The performance characteristics of the CAP System FEIA for soy and wheat were poor. For egg, milk, peanut, and fish allergy, diagnostic levels of IgE, which could predict clinical reactivity in this population with greater than 95% certainty, were identified: egg, 6 kilounits of allergen-specific IgE per liter (kU[A]/L); milk, 32 kU(A)/L; peanut, 15 kU(A)/L; and fish, 20 kU(A)/L . CONCLUSIONS: When compared with the outcome of DBPCFCs, results of CAP System FEIA are generally comparable to those of skin prick tests in predicting symptomatic food hypersensitivity. Furthermore, by measuring the concentrations of food-specific IgE antibodies with the CAP System FEIA, it is possible to identify a subset of patients who are highly likely (>95%) to experience clinical reactions to egg, milk, peanut, or fish. This could eliminate the need to perform DBPCFCs in a significant number of patients suspected of having IgE-mediated food allergy."

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[187] - Salvatori N, Reccardini F, Convento M, Purinan A, Colle R, De Carli S, et al. Asthma induced by inhalation of flour in adults with food allergy to wheat. Clin Exp Allergy 2008;38:1349-1356

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[188] - Jones SM, Magnolfi CF, Cooke SK, Sampson HA. Immunologic cross-reactivity among cereal grains and grasses in children with food hypersensitivity. J Allergy Clin Immunol 1995;96:341-351

Because of a lack of clinical data from food challenges, allergists often recommend dietary restriction of all cereal grains in patients with sensitivity to at least one grain. OBJECTIVES: The purposes of this study were to assess the degree of intrabotanical cross-reactivity among cereal grains and related grasses, to better define the prevalence of multiple grain hypersensitivity, and to define the protein fractions associated with wheat hypersensitivity. METHODS: One hundred forty-five patients evaluated by food challenges and skin prick tests were divided into three groups: group 1, cereal grain and grass allergies; group 2, wheat allergy alone; and group 3, grass allergy alone. Fifteen patients were further selected from groups 1 to 3. Sodium dodecylsulfate--polyacrylamide gel electrophoresis and immunoblot analyses were performed on six grains and four related grasses with sera from these patients. RESULTS: Only 21% of patients had symptomatic reactivity as determined by food challenge; 80% had reactivity to only one grain. As determined by immunoblot analyses, patients in groups 1 and 2 showed extensive cross-reactivity (within each group) among grains but little cross-reactivity among grasses, whereas patients in group 3 showed cross-reactivity between the grains and grasses. Patients with wheat allergy had specific IgE binding to wheat fractions 47 kd and 20 kd, bands not recognized by patients with grass allergy. CONCLUSIONS: Clinically insignificant cross-reactivity exists among cereal grains and grasses; therefore, elimination of all grains from the diet of a patient with grain allergy is unwarranted. Further purification and characterization of the 47 kd and 20 kd wheat fractions is needed to provide more specific in vitro testing.

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[189] - Scibilia J, Pastorello EA, Zisa G, Ottolenghi A, Bindslev-Jensen C, Pravettoni V, et al. Wheat allergy: A double-blind, placebo-controlled study in adults. J Allergy Clin Immunol 2006;117:433-439

BACKGROUND: Wheat is believed to be an uncommon cause of food allergy in adults; the number of studies that address IgE mediated wheat allergy in adults is all too few . OBJECTIVE: Determine how many subjects with a history of wheat allergy have real allergy by double-blind, placebo-controlled food challenge; identify the symptoms manifested during the challenge; determine the lowest provocation dose; determine the performance characteristics of wheat skin prick test and specific IgE; identify subjects with real wheat allergy for potential immunoblotting studies . METHODS: Patients underwent skin test with commercial wheat extract; specific wheat IgE was determined. Subjects were challenged with 25 g wheat. Subjects who were positive to raw wheat challenge underwent cooked wheat challenge . RESULTS: Thirty-seven double-blind placebo-controlled wheat challenges were performed on 27 patients. A total of 13 of 27 (48%) patients had a positive result. Eleven subjects with positive raw wheat challenge underwent cooked wheat challenge: 10 were positive. The provocation dose range was 0.1 to 25 g. Twenty-seven percent of the subjects allergic to wheat had a provocation dose that was < or =1.6 g . CONCLUSION: Wheat causes real food allergy in adults. More than a quarter of the patients allergic to wheat reacted to less than 1.6 g wheat. Specific IgE was more sensitive than skin test for wheat; however, specificity and predictive values were low for both tests. Thus, these tests should not be used to validate diagnosis of wheat allergy.

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[190] - de Boissieu D, Dupont C. Dermatite atopique de l'enfant et allergie au blé. Rev Fr Allergol Immunol Clin 2005;45:411-415

La fréquence de l'allergie au blé au cours de la dermatite atopique de l'enfant est évaluée entre 14 et 18 %. Elle a la particularité de se manifester souvent par des réactions retardées, avec des manifestations cutanées ou digestives. Les réactions immédiates sévères semblent relativement rares. La négativité des pricks tests et des IgE spécifiques au blé n'éliminent pas le diagnostic. Le test épicutané à la farine de blé semble le meilleur examen de dépistage, mais est peu spécifique chez le très jeune enfant. Le diagnostic doit être confirmé par un test de provocation qui doit être prolongé sur plusieurs jours en raison de la fréquence des réactions retardées.

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[191] - Niggemann B, Reibel S, Wahn U. The atopy patch test (APT)-- a useful tool for the diagnosis of food allergy in children with atopic dermatitis. Allergy 2000;55:281-285

BACKGROUND: While immediate-type clinical reactions to food can quite easily be identified by history or measurement of specific IgE in combination with positive oral food challenges, the evaluation of food allergy in the absence of immediate clinical reactions still presents diagnostic difficulties--particularly in children with atopic dermatitis. The objective of this study was to evaluate the diagnostic value of the atopy patch test (APT) with regard to late-phase reactions observed in double-blind, placebo-controlled food challenges with cow's milk, hen's egg, wheat, and soybean. METHODS: We investigated 75 children (median age 2.1 years) with suspected food allergy by double-blind, placebo-controlled food challenges, specific IgE in serum, skin prick test, and APT. Of the subjects, 69/75 suffered from atopic dermatitis. RESULTS: Of 209 oral challenges, 133 were performed with allergen and 76 with placebo. We assessed 77/133 allergen and 2/76 placebo challenges as positive. In 66 of 77 (86%) positive oral challenges, specific IgE in serum to the corresponding allergen was positive; in 64/77 (83%) the skin prick test, and in 42/77 (55%) the APT was positive. While immediate-type reactions were associated with positive skin prick test and proof of specific IgE in serum, late-phase clinical reactions were associated with a positive APT (sensitivity 76%, specificity 95%). CONCLUSIONS: The APT seems to be a valuable additional tool in the diagnostic work-up of food allergy in children with atopic dermatitis - especially with regard to late-phase clinical reactions. The APT may help to prevent unnecessary restrictive diets which may be the consequence of misjudging late reactions by clinical assessment alone

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[192] - Majamaa H, Moisio P, Holm K, Turjanmaa K. Wheat allergy: diagnostic accuracy of skin prick and patch tests and specific IgE. Allergy 1999;54:851-856

BACKGROUND: Food allergy makes an important contribution to the pathogenesis of atopic eczema in infants. However, clinical data on cereal allergy are scanty. The objective was to study the relevance of patch testing, skin prick tests, and the concentration of wheat-specific IgE antibodies (CAP RAST) in correlation with oral wheat challenge in infants with suspected wheat allergy. In particular, we aimed to determine whether the patch test could increase the diagnostic accuracy in detecting wheat allergy. METHODS: The study material comprised 39 infants under the age of 2 years. Of these patients, 36 were suffering from atopic eczema and three had only gastrointestinal symptoms. The patients were subjected to a double-blind, placebo-controlled or open wheat challenge. Wheat-specific IgE was measured by CAP RAST, and skin prick and patch tests were performed. RESULTS: Of the total 39 wheat challenges, 22 (56%) were positive. Of the positive reactions, five involved immediate-type skin reactions over a period of 2 h from the commencement of the challenge. In 17 patients, delayed-onset reactions of eczematous or gastrointestinal type appeared. Of the infants with challenge-proven wheat allergy, 20% showed elevated IgE concentrations to wheat, 23% had a positive skin prick test, and 86% had a positive patch test for wheat. The specificities of CAP RAST, skin prick tests, and patch tests were 0.93, 1.00, and 0.35, respectively. CONCLUSIONS: Our study demonstrated that patch testing with cereals will significantly increase the probability of early detection of cereal allergy in infants with atopic eczema and is helpful in the planning of successful elimination diets before challenge. The specificity of the patch test was lower than that of other tests. Therefore, confirmation of the diagnosis with the elimination-challenge test is essential in patients with positive patch test results.

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[193] - Järvinen KM, Turpeinen M, Suomalainen H. Concurrent cereal allergy in children with cow’s milk allergy manifested with atopic dermatitis. Clin Exp Allergy 2003;33:1060-1066

BACKGROUND: There is increasing consensus about the significance of food allergens in the pathogenesis of atopic dermatitis (AD) in infancy and childhood, with cow's milk and egg accounting for most of the reactions. Previous studies have indicated that multiple food sensitization, such as cereals, is very common in patients with cow's milk allergy (CMA). Evidence is lacking, however, as to its clinical relevance . OBJECTIVE: The purpose of this study was to determine the concurrent occurrence of cereal allergy among children with challenge-proven CMA who have residual symptoms, such as AD and/or gastrointestinal symptoms, during cow's milk elimination diet. Further, we sought to evaluate the utility of patch testing in prescreening foods other than cow's milk behind allergic symptoms in children . METHODS: The study population comprised 90 children, aged from 2.5 to 36 months (mean 1.1 years), with challenge-proven CMA. As a result of residual symptoms during meticulous cow's milk elimination diet (AD: n=80, and gastrointestinal: n=10), the children were put on a cereal elimination diet (oats, wheat, rye, and barley) and skin prick tests (SPT) and patch testing with cereals were performed. Open cereal challenge was performed to confirm cereal allergy . RESULTS: Cereal challenge was positive in 66 (73%) of the children with CMA. Of them, 17% reacted with immediate reactions and delayed-onset reactions were seen in 83% of the children. SPT was positive in 23%, patch test in 67%, and either SPT or patch test was positive in 73% of the children with cereal allergy. SPT gave the best positive predictive value, whereas SPT together with patch test gave the best negative predictive value . CONCLUSIONS: Residual symptoms, such as eczema or gastrointestinal symptoms in CMA children may be a sign of undetected allergy to other food antigens. SPT with cereals aids in diagnosing cereal allergy in small children, especially when used together with patch testing.

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[194] - Roehr CC, Reibel S, Ziegert M, Sommerfeld C, Wahn U, Niggemann B. Atopy patch tests, together with determination of IgE levels, reduce the need for need for oral food challenges in children with atopic dermatitis. J Allergy Clin Immunol 2001;107:548-553

BACKGROUND: Atopic dermatitis is commonly associated with food allergy. In addition to skin prick tests (SPTs) and measurements of specific IgE levels, the atopy patch test (APT) has recently been introduced into the diagnostic procedure for food allergy . OBJECTIVE: Our aim was to evaluate whether a combination of allergologic tests could improve the prognostic value of the individual tests for positive food challenge results. We hypothesized that the combination of a positive APT result plus proof of specific IgE, a positive SPT result, or both would render double-blind, placebo-controlled, food challenges unnecessary . METHODS: One hundred seventy-three double-blind, placebo-controlled, food challenges were performed in 98 children (median age, 13 months) with atopic dermatitis. All children were subjected to SPTs, APTs, and determination of specific IgE. Sensitivity, specificity, and positive and negative predictive values were calculated . RESULTS: Ninety-five (55%) of 173 oral provocations were assessed as positive. For evaluating suspected cow's milk (CM) allergy, the APT was the best single predictive test (positive predictive value [PPV], 95%), and the combination of a positive APT result with evidence of specific IgE or an APT result together with a positive skin prick test response optimized the PPV to 100%. For hen's egg (HE) allergy, the APT was also the best single predictive test (PPV, 94%). The combination of 2 or more tests did not exceed the APT's predictive value. In both CM and HE challenges, the predictability of oral challenges depended on the level of specific IgE. For wheat allergy, the APT proved to be the most reliable test, and the PPV of 94% could not be improved by a combination with other allergologic tests . CONCLUSION: The combination of positive APT results and measurement of levels of specific IgE (CM, > or = 0.35 kU/L; HE, > or = 17.5 kU/L) makes double-blind, placebo-controlled, food challenges superfluous for suspected CM and HE allergy.

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[195] - Moneret-Vautrin DA, Lemerdy P. VPP des prick tests aux aliments natifs: vers un diagnostic absolu ? Alim'Inter 2006;11:228-232

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[196] - Niggemann B, Verstege A, Mehl A, Rolinck-Werninghaus C, Nocon M, Beyer K. The Predictive Value of Skin Prick Tests for the Outcome of Oral Food Challenges in Children With Atopic Dermatitis. J Allergy Clin Immunol 2005;115(2 suppl.):S101

RATIONALE: The Skin Prick Test (SPT) is considered an important measure in the diagnostic work-up of food allergy Objective: To evaluate the role of the SPT in predicting the outcome of food challenges, and to determine threshold levels of SPTs that could render double-blind, placebo-controlled food challenges unnecessary METHODS: In 391 children (median age 22 months), 758 controlled oral challenges were performed with cowâ_˙s milk (CM), henâ_˙s egg (HE), wheat and soy. 342/391 (88%) children suffered from atopic dermatitis For all children, absolute SPT wheal diameters and the skin index (defined as the ratio of the allergen wheal to the histamine wheal diameter) were determined. Sensitivity, specificity, positive and negative predictive values, ROC-curves as well as predictive decision points were calculated RESULTS: 297/758 oral food challenges with allergens were assessed as positive. Sensitivity of SPT was 93% for HE, 87% for CM, 24% for soy, and 66% for wheat. Specificity was 57% for HE, 73% for CM, 88% for soy, and 77% for wheat. Calculating 90%, 95% and 99% predicted probabilities using logistic regression revealed predictive decision points of 11.9 mm (skin index 2.6), 15.0 mm (skin index 3.4), and 21.8 mm (skin index 5.3) for HE, respectively. For CM, only the 90% predicted probability (17.7 mm, skin index 4.5) could be calculated. No decision points could be determined for wheat and soy CONCLUSION: SPT predictive decision points can be calculated for HE, which may help to avoid oral food challenges in some cases. However, data need to be ascertained for each allergen separately

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[197] - Sward-Nordmo M, Paulsen BS, Wold JK. The glycoprotein allergen Ag-54 (Cla h II) from Cladosporium herbarum. Structural studies of the carbohydrate moiety. Int Arch Allergy Appl Immunol 1988;85:288-294

The carbohydrate moiety of an important allergen, Ag-54 in Cladosporium herbarum was studied by alkaline-borohydride treatment, gel filtration, high-performance liquid chromatography, methylation analysis, gas liquid chromatography and mass spectometry. The Ag-54 protein core possessed a very limited number of sugar chains. The carbohydrate moiety consisted mainly of one large highly branched polysaccharide chain which accounted for nearly 75% of the total molecular weight of the glycoprotein. The carbohydrate moiety is made up of D-mannose and D-glucose units in pyranose form having D-galactofuranose side chains attached. Mannose is both 1,2- and 1,6-linked, while glucose is 1,4- and 1,6-linked. Some of the 1,6-linked galactofuranose side chains are bound through C-2 of the 1,6-linked mannose units, and the rest to C-3 of 1,6-linked mannose and 1,2-linked mannose units. A few oligoglucosidic chains of approximately 4 glucose units are also attached to the protein.

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[198] - Räsänen L, Lehto M, Turjanmaa K, Savolainen J, Reunala T. Allergy to ingested cereals in atopic children. Allergy 1994;49:871-876

Clinical features, hypersensitivity mechanisms, and differential diagnosis of cereal allergy or intolerance were investigated in children with atopic dermatitis (AD). On oral provocation, 18 children exhibited a positive response to wheat, three to rye, one to barley, and one to oats. Cereal-induced symptoms were dermatologic, gastrointestinal, or oropharyngeal, and their onset after provocation was immediate (eight cases), delayed (14 cases), or both immediate and delayed (one case). A combination of type I allergy tests (prick test, RAST, and histamine-release test) detected all immediate reactors and 9/14 delayed reactors. Of the five subjects remaining negative in these tests, three were positive in the patch or lymphocyte-proliferation tests. Subjects with cereal allergy or intolerance frequently possessed IgE, IgA, and IgG antibodies against gliadin, but only one of these children was HLA-DR3-positive, and none had reticulin antibodies typical of celiac disease. Combining tests of immediate and delayed hypersensitivity can confirm allergy to cereals in a more reliable way. The coexistence of cereal allergy and celiac disease seems to be rare.

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[199] - Majamaa H, Moisio P, Holm K, Turjanmaa K. Wheat allergy: diagnostic accuracy of skin prick and patch tests and specific IgE. Allergy 1999;54:851-856

BACKGROUND: Food allergy makes an important contribution to the pathogenesis of atopic eczema in infants. However, clinical data on cereal allergy are scanty. The objective was to study the relevance of patch testing, skin prick tests, and the concentration of wheat-specific IgE antibodies (CAP RAST) in correlation with oral wheat challenge in infants with suspected wheat allergy. In particular, we aimed to determine whether the patch test could increase the diagnostic accuracy in detecting wheat allergy. METHODS: The study material comprised 39 infants under the age of 2 years. Of these patients, 36 were suffering from atopic eczema and three had only gastrointestinal symptoms. The patients were subjected to a double-blind, placebo-controlled or open wheat challenge. Wheat-specific IgE was measured by CAP RAST, and skin prick and patch tests were performed. RESULTS: Of the total 39 wheat challenges, 22 (56%) were positive. Of the positive reactions, five involved immediate-type skin reactions over a period of 2 h from the commencement of the challenge. In 17 patients, delayed-onset reactions of eczematous or gastrointestinal type appeared. Of the infants with challenge-proven wheat allergy, 20% showed elevated IgE concentrations to wheat, 23% had a positive skin prick test, and 86% had a positive patch test for wheat. The specificities of CAP RAST, skin prick tests, and patch tests were 0.93, 1.00, and 0.35, respectively. CONCLUSIONS: Our study demonstrated that patch testing with cereals will significantly increase the probability of early detection of cereal allergy in infants with atopic eczema and is helpful in the planning of successful elimination diets before challenge. The specificity of the patch test was lower than that of other tests. Therefore, confirmation of the diagnosis with the elimination-challenge test is essential in patients with positive patch test results.

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[200] - Järvinen KM, Turpeinen M, Suomalainen H. Concurrent cereal allergy in children with cow’s milk allergy manifested with atopic dermatitis. Clin Exp Allergy 2003;33:1060-1066

BACKGROUND: There is increasing consensus about the significance of food allergens in the pathogenesis of atopic dermatitis (AD) in infancy and childhood, with cow's milk and egg accounting for most of the reactions. Previous studies have indicated that multiple food sensitization, such as cereals, is very common in patients with cow's milk allergy (CMA). Evidence is lacking, however, as to its clinical relevance . OBJECTIVE: The purpose of this study was to determine the concurrent occurrence of cereal allergy among children with challenge-proven CMA who have residual symptoms, such as AD and/or gastrointestinal symptoms, during cow's milk elimination diet. Further, we sought to evaluate the utility of patch testing in prescreening foods other than cow's milk behind allergic symptoms in children . METHODS: The study population comprised 90 children, aged from 2.5 to 36 months (mean 1.1 years), with challenge-proven CMA. As a result of residual symptoms during meticulous cow's milk elimination diet (AD: n=80, and gastrointestinal: n=10), the children were put on a cereal elimination diet (oats, wheat, rye, and barley) and skin prick tests (SPT) and patch testing with cereals were performed. Open cereal challenge was performed to confirm cereal allergy . RESULTS: Cereal challenge was positive in 66 (73%) of the children with CMA. Of them, 17% reacted with immediate reactions and delayed-onset reactions were seen in 83% of the children. SPT was positive in 23%, patch test in 67%, and either SPT or patch test was positive in 73% of the children with cereal allergy. SPT gave the best positive predictive value, whereas SPT together with patch test gave the best negative predictive value . CONCLUSIONS: Residual symptoms, such as eczema or gastrointestinal symptoms in CMA children may be a sign of undetected allergy to other food antigens. SPT with cereals aids in diagnosing cereal allergy in small children, especially when used together with patch testing.

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[201] - Sicherer SH, Morrow EH, Sampson HA. Dose-response in double-blind, placebo-controlled oral food challenges in children with atopic dermatitis. J Allergy Clin Immunol 2000;105:582-586

"BACKGROUND: Double-blind, placebo-controlled oral food challenges (DBPCFCs) are considered the ""gold standard"" for diagnosing food hypersensitivity, but the dose that elicits positive challenges, or determinants that may predict dose-response relationships, have not been reported . OBJECTIVE: Our purpose was to determine the quantity of food that elicits reactions during DBPCFCs and to evaluate parameters that may predict the provocative dose and severity of reaction . METHODS: We reviewed challenge data for all positive challenges to 6 common allergenic foods in children with atopic dermatitis evaluated for food allergy over a 13-year period. Challenge food was generally administered in 6 doses at 10- to 15-minute intervals beginning with 400 to 500 mg and completing with a total of 8 to 10 g of food. An open feeding of a larger portion followed negative challenges. At the physician's discretion, a lower starting dose was occasionally used (100 mg, 250 mg). Food-specific IgE antibody concentrations (radioallergosorbent test [RAST]) were determined on stored sera of 20% of the challenges selected randomly and 99.6% had prick skin tests (PSTs) performed to the challenged food . RESULTS: A total of 196 children (45% male; median age 5 y 9 mo; atopic dermatitis 98%, asthma 62%) had 513 positive challenges distributed as follows: egg 267, milk 117, soy 53, wheat 40, peanut 24, fish 12. The percentage of children reacting at the first dose (500 mg or less) was as follows: egg 49%, milk 55%, soy 28%, wheat 25%, peanut 26%, and fish 17%. Twenty-six milk challenges and 22 egg challenges were positive at a first dose of 250 mg; 3 milk challenges and 7 egg challenges were positive at a first dose of 100 mg. Eleven percent of the reactions that occurred on the first dose were severe. The percentage reacting after the final dose of the DBPCFC (or during open challenge) were egg 11%, milk 12%, soy 19%, wheat 12.5%, peanut 8.7%, and fish 25%. There was not a strong correlation between PST absolute wheal size or score (adjusted for histamine controls) and dose at reaction or severity of reaction (R(s) range -0.22 to 0.39 for particular foods). Serum concentration of food-specific IgE did not correlate well with the dose causing a reaction or with severity (R(s) range -0.40 to 0.55 for particular foods) . CONCLUSIONS: This food-allergic population may react to as little as 100 mg of food, possibly less, and the dose causing a reaction and the severity of reaction is not predicted by PST or RAST. Lower doses (100 mg or less) should be investigated for their appropriateness in initiating DBPCFCs."

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[202] - Sander I, Merget R, Degens PO, Goldscheid N, Brüning T, Raulf-Heimsoth M. Comparison of wheat and rye flour skin prick test solutions for diagnosis of baker’s asthma. Allergy 2004;59:95-98

BACKGROUND: Skin prick tests (SPTs) play an important role in the diagnosis of baker's asthma and in the investigation of sensitization frequencies in field studies. It was the aim of our study to compare different SPT solutions for wheat and rye flour sensitization and to assess the validity of test results . METHODS: Skin prick tests with wheat and rye flour were performed in parallel with extracts from different companies and compared with the results of bronchial challenge tests with both flours (69 rye flour and 51 wheat flour challenge tests). Additionally, specific immunoglobulin E (sIgE) to wheat and rye flour were tested. SPT solutions were analysed for protein content and by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) . RESULTS: Skin prick test solutions for diagnosis of wheat and rye flour sensitization from three companies differed in protein concentrations and composition with the consequence of widely differing SPT results. Sensitivity of SPTs in comparison with allergen-specific bronchial challenge as a gold standard was between 40 and 67%, specificity was between 86 and 100%, the positive predictive value (PPV) ranged from 81 to 100% and the negative predictive value (NPV) from 44 to 70%. These numbers were only marginally affected by using a combination of challenge test result and sIgE value as a more specific gold standard . CONCLUSION: Improvement and standardization of SPT extracts for wheat and rye flour is highly recommended.

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[203] - van Kampen V, Rabstein S, Sander I, Merget R, Brüning T, Broding HC, et al. Prediction of challenge test results by flour-specific IgE and skin prick test in symptomatic bakers. Allergy 2008;63:897-902

BACKGROUND: Wheat and rye flours are among the most important allergens causing occupational asthma. Usually, the diagnosis of baker's asthma is based on inhalation challenge tests with flours. AIMS OF THE STUDY: To evaluate the relevance of flour-specific serum immunoglobulin E (IgE) and skin prick test (SPT) in the diagnosis of baker's asthma and to define flour-specific IgE concentrations and wheal sizes that allow a prediction of the outcome of challenge testing . METHODS: Bronchial and nasal challenge tests with wheat (rye) flour were performed in 71 (95) symptomatic bakers. Determinations of flour-specific IgE as well as SPTs were performed in all subjects. Analyses included the calculation of sensitivity, specificity, positive (PPV) and negative predictive values (NPV) at different IgE concentrations and different wheal sizes, and receiver-operating characteristics (ROC) plots with the challenge result as gold standard . RESULTS: Thirty-seven bakers were positive in the challenge with wheat flour, while 63 were positive with rye flour. Depending on the flour-specific IgE concentrations (wheal size), PPV was 74-100% (74-100%) for wheat and 82-100% (91-100%) for rye flour, respectively. The minimal cut-off values with a PPV of 100% were 2.32 kU/l (5.0 mm) for wheat flour and 9.64 kU/l (4.5 mm) for rye flour. The shapes of the ROC plots were similar for wheat and rye flour . CONCLUSION: High concentrations of flour-specific IgE and clear SPT results in symptomatic bakers are good predictors for a positive challenge test. Challenge tests with flours may be avoided in strongly sensitized bakers.

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[204] - Majamaa H, Moisio P, Holm K, Turjanmaa K. Wheat allergy: diagnostic accuracy of skin prick and patch tests and specific IgE. Allergy 1999;54:851-856

BACKGROUND: Food allergy makes an important contribution to the pathogenesis of atopic eczema in infants. However, clinical data on cereal allergy are scanty. The objective was to study the relevance of patch testing, skin prick tests, and the concentration of wheat-specific IgE antibodies (CAP RAST) in correlation with oral wheat challenge in infants with suspected wheat allergy. In particular, we aimed to determine whether the patch test could increase the diagnostic accuracy in detecting wheat allergy. METHODS: The study material comprised 39 infants under the age of 2 years. Of these patients, 36 were suffering from atopic eczema and three had only gastrointestinal symptoms. The patients were subjected to a double-blind, placebo-controlled or open wheat challenge. Wheat-specific IgE was measured by CAP RAST, and skin prick and patch tests were performed. RESULTS: Of the total 39 wheat challenges, 22 (56%) were positive. Of the positive reactions, five involved immediate-type skin reactions over a period of 2 h from the commencement of the challenge. In 17 patients, delayed-onset reactions of eczematous or gastrointestinal type appeared. Of the infants with challenge-proven wheat allergy, 20% showed elevated IgE concentrations to wheat, 23% had a positive skin prick test, and 86% had a positive patch test for wheat. The specificities of CAP RAST, skin prick tests, and patch tests were 0.93, 1.00, and 0.35, respectively. CONCLUSIONS: Our study demonstrated that patch testing with cereals will significantly increase the probability of early detection of cereal allergy in infants with atopic eczema and is helpful in the planning of successful elimination diets before challenge. The specificity of the patch test was lower than that of other tests. Therefore, confirmation of the diagnosis with the elimination-challenge test is essential in patients with positive patch test results.

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[205] - Räsänen L, Lehto M, Turjanmaa K, Savolainen J, Reunala T. Allergy to ingested cereals in atopic children. Allergy 1994;49:871-876

Clinical features, hypersensitivity mechanisms, and differential diagnosis of cereal allergy or intolerance were investigated in children with atopic dermatitis (AD). On oral provocation, 18 children exhibited a positive response to wheat, three to rye, one to barley, and one to oats. Cereal-induced symptoms were dermatologic, gastrointestinal, or oropharyngeal, and their onset after provocation was immediate (eight cases), delayed (14 cases), or both immediate and delayed (one case). A combination of type I allergy tests (prick test, RAST, and histamine-release test) detected all immediate reactors and 9/14 delayed reactors. Of the five subjects remaining negative in these tests, three were positive in the patch or lymphocyte-proliferation tests. Subjects with cereal allergy or intolerance frequently possessed IgE, IgA, and IgG antibodies against gliadin, but only one of these children was HLA-DR3-positive, and none had reticulin antibodies typical of celiac disease. Combining tests of immediate and delayed hypersensitivity can confirm allergy to cereals in a more reliable way. The coexistence of cereal allergy and celiac disease seems to be rare.

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[206] - Roehr CC, Reibel S, Ziegert M, Sommerfeld C, Wahn U, Niggemann B. Atopy patch tests, together with determination of IgE levels, reduce the need for need for oral food challenges in children with atopic dermatitis. J Allergy Clin Immunol 2001;107:548-553

BACKGROUND: Atopic dermatitis is commonly associated with food allergy. In addition to skin prick tests (SPTs) and measurements of specific IgE levels, the atopy patch test (APT) has recently been introduced into the diagnostic procedure for food allergy . OBJECTIVE: Our aim was to evaluate whether a combination of allergologic tests could improve the prognostic value of the individual tests for positive food challenge results. We hypothesized that the combination of a positive APT result plus proof of specific IgE, a positive SPT result, or both would render double-blind, placebo-controlled, food challenges unnecessary . METHODS: One hundred seventy-three double-blind, placebo-controlled, food challenges were performed in 98 children (median age, 13 months) with atopic dermatitis. All children were subjected to SPTs, APTs, and determination of specific IgE. Sensitivity, specificity, and positive and negative predictive values were calculated . RESULTS: Ninety-five (55%) of 173 oral provocations were assessed as positive. For evaluating suspected cow's milk (CM) allergy, the APT was the best single predictive test (positive predictive value [PPV], 95%), and the combination of a positive APT result with evidence of specific IgE or an APT result together with a positive skin prick test response optimized the PPV to 100%. For hen's egg (HE) allergy, the APT was also the best single predictive test (PPV, 94%). The combination of 2 or more tests did not exceed the APT's predictive value. In both CM and HE challenges, the predictability of oral challenges depended on the level of specific IgE. For wheat allergy, the APT proved to be the most reliable test, and the PPV of 94% could not be improved by a combination with other allergologic tests . CONCLUSION: The combination of positive APT results and measurement of levels of specific IgE (CM, > or = 0.35 kU/L; HE, > or = 17.5 kU/L) makes double-blind, placebo-controlled, food challenges superfluous for suspected CM and HE allergy.

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[207] - Moneret-Vautrin DA, Kanny G, Perrier P, Denery-Papini S, Morisset M, Leduc V, et al. Etude prospective 1999-2002 de l'allergie alimentaire à la farine de blé chez l'enfant et chez l'adulte, comparée à la maladie coeliaque. Association de DR1 à l'allergie chez l'enfant. Alim'Inter 2003;8:2-8

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[208] - Halvorsen R, Dahlström J, Aas M, Tørres T. Anaphylactic reactions to wheat. Allergy Clin Immunol Int 2005;17(Suppl. 1):351

Background: Sensitisation to wheat is common in small children. However, reactions to ingested wheat are seldom seen and mostly associated with atopic eczema and exercise induced anaphylaxis. There are only few reports of anaphylactic reactions to wheat without exercise. We report 10 children with serious reactions to wheat containing food and compare them with 19 patients with sensitisation, but no clinical reactions. Methods: 29 children with IgE sensitisation to wheat were referred to Voksentoppen, Oslo, for further diagnostic procedures. All children had specific IgE to wheat. and were thus advised to avoid wheat in their diet. Skin prick test, total and specific IgE as well as oral provocation tests were performed. Results: Ten out of 29 children had severe reactions upon challenge with wheat containing food and were treated with adrenalin and, in most cases, oral steroids. Six out of 10 children with severe reactions had more than 100 kU/L of specific IgE to wheat, two had 90 - 100 kU/L, one had 46 and one 6 kU/L. Of the 19 children with no reaction after wheat intake, five had more than 100 kU/L of specific IgE to wheat, six had 55-100 kU/L and the remainder had values between 4 and 55 kUa/L. Specific IgE against other wheat proteins, such as gluten and gliadin, correlated closely with specific IgE to wheat. Conclusions: It is important to identify children at risk for general reactions to wheat, as cereals are common foods. In order to identify children at risk for anaphylactic reactions to ingested wheat, specific IgE against wheat without clinical investigation is of little use. Food challenge is today the only possible way to identify these children, and to avoid serious reactions upon challenge it is essential to identify the proteins involved in the anaphylactic reactions.

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[209] - Celik-Bilgili S, Mehl A, Verstege A, Staden U, Nocon M, Beyer K, et al. The predictive value of specific immunoglobulin E levels in serum for the outcome of oral food challenges. Clin Exp Allergy 2005;35:268-273

Summary Background Specific serum IgE is considered as one of the important diagnostic measures in the diagnostic work-up of food allergy. Objective To evaluate the role of specific serum IgE in predicting the outcome of oral food challenges, and to determine threshold concentrations of specific serum IgE that could render double-blind, placebo-controlled food challenges unnecessary. Methods In 501 children (median age 13 months), 992 controlled oral challenges were performed with cow's milk (CM), hen's egg (HE), wheat and soy. 440/501 (88%) children suffered from atopic dermatitis. For all children, specific IgE concentrations in serum were determined. Sensitivity, specificity, positive and negative predictive values, receiver operator characteristics-curves as well as predictive decision points were calculated. Results Four hundred and forty-five out of 992 oral food challenges with allergens were assessed as positive. Sensitivity of specific serum IgE was 97% for HE, 83% for CM, 69% for soy, and 79% for wheat. Specificity was 51% for HE, 53% for CM, 50% for soy, and 38% for wheat. Calculating 90%, 95% and 99% predicted probabilities using logistic regression revealed predictive decision points of 6.3, 12.6, and 59.2 kU/L for HE, respectively. Subdividing our children in those of below or above 1 year of age resulted in a markedly different predicted probability for HE. For CM, only the 90% predicted probability (88.8 kU/L) could be calculated. No decision points could be determined for CM, wheat and soy. Conclusion In general, specific serum IgE levels showed a correlation with the outcome of positive oral food challenges for CM and HE. Meaningful predictive decision points can be calculated for HE, which may help to avoid oral food challenges in some cases. However, data need to be ascertained for each allergen separately. Furthermore, the age of the patient population under investigation must also be taken into account.

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[210] - Sampson HA, Ho DG. Relationship between food-specific IgE concentrations and the risk of positive food challenges in children and adolescents. J Allergy Clin Immunol 1997;100:444-451

"BACKGROUND: The double-blind, placebo-controlled food challenge (DBPCFC) is the ""gold standard"" for diagnosis of food hypersensitivity. Skin prick tests and RASTs are sensitive indicators of food-specific IgE antibodies but poor predictors of clinical reactivity. Previous studies suggested that high concentrations of food-specific IgE antibody were predictive of food-induced clinical symptoms. Because the CAP System FEIA (Pharmacia Diagnostics, Uppsala, Sweden) provides a quantitative assessment of allergen-specific IgE antibody, this study was undertaken to determine the potential utility of the CAP System FEIA in diagnosis of IgE-mediated food hypersensitivity . METHODS: Sera from 196 patients with food allergy were analyzed for specific IgE antibodies to egg, milk, peanut, soy, wheat, and fish by CAP System FEIA. Sera were randomly selected from 300 stored samples of children and adolescents who had been evaluated by history, skin prick tests, and DBPCFCs. The study population was highly atopic; all patients had atopic dermatitis, and approximately 50% had asthma and allergic rhinitis at the time of initial evaluation. The performance characteristics of the CAP System FEIA were compared with those of skin prick tests and the outcome of DBPCFCs or ""convincing"" histories of anaphylactic reactions . RESULTS: The prevalence of specific food allergies in the study population varied from 22% for wheat to 73% for egg. Allergy to egg, milk, peanut, and soy accounted for 87% of confirmed reactions. The performance characteristics of skin prick tests and CAP System FEIA (egg, milk, peanut, fish) were comparable, with excellent sensitivity and negative predictive accuracy but poor specificity and positive predictive accuracy. The performance characteristics of the CAP System FEIA for soy and wheat were poor. For egg, milk, peanut, and fish allergy, diagnostic levels of IgE, which could predict clinical reactivity in this population with greater than 95% certainty, were identified: egg, 6 kilounits of allergen-specific IgE per liter (kU[A]/L); milk, 32 kU(A)/L; peanut, 15 kU(A)/L; and fish, 20 kU(A)/L . CONCLUSIONS: When compared with the outcome of DBPCFCs, results of CAP System FEIA are generally comparable to those of skin prick tests in predicting symptomatic food hypersensitivity. Furthermore, by measuring the concentrations of food-specific IgE antibodies with the CAP System FEIA, it is possible to identify a subset of patients who are highly likely (>95%) to experience clinical reactions to egg, milk, peanut, or fish. This could eliminate the need to perform DBPCFCs in a significant number of patients suspected of having IgE-mediated food allergy."

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[211] - Sampson HA. Utility of food-specific IgE concentrations in predicting symptomatic food allergy. J Allergy Clin Immunol 2001;107:891-896

BACKGROUND: The double-blind, placebo-controlled food challenge is considered the gold standard for diagnosing food allergy. However, in a retrospective analysis of children and adolescents with atopic dermatitis and food allergy, discrete food-specific IgE concentrations were established that could predict clinical reactivity to egg, milk, peanut, and fish with greater than 95% certainty. OBJECTIVE: The purpose of this investigation was to determine the utility of these 95% predictive decision points in a prospective evaluation of food allergy. METHODS: Sera from 100 consecutive children and adolescents referred for evaluation of food allergy were analyzed for specific IgE antibodies to egg, milk, peanut, soy, wheat, and fish by using the Pharmacia CAP System FEIA. Food-specific IgE values were compared with history and the results of skin prick tests and food challenges to determine the efficacy of previously established 95% predictive decision points in identifying patients with increased probability of reacting during a specific food challenge. RESULTS: One hundred children (62% male; median age, 3.8 years; range, 0.4-14.3 years) were evaluated for food allergy. The diagnosis of food allergy was established by means of history or oral food challenge. On the basis of the previously established 95% predictive decision points for egg, milk, peanut, and fish allergy, greater than 95% of food allergies diagnosed in this prospective study were correctly identified by quantifying serum food-specific IgE concentrations. CONCLUSION: In a prospective study of children and adolescents referred for evaluation of food allergy, previously established 95% predictive decision points of food-specific IgE antibody concentrations for 4 major food allergens were effective in predicting clinical reactivity. Quantification of food-specific IgE is a useful test for diagnosing symptomatic allergy to egg, milk, peanut, and fish in the pediatric population and could eliminate the need to perform double-blind, placebo-controlled food challenges in a significant number of children.

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[212] - Komata T, Imai T, Tomikawa M, Tachimoto H, Shukuya A, Ebisawa M. Usefulness of egg white, milk, wheat and soy specific IgE antibody titers in the diagnosis of food allergy. Allergy Clin Immunol Int 2005;17(Suppl. 1):331-332

Background: The relationship between food-specific IgE titers and the outcome of food challenges is established through threshold values and probability curves. One major difference between the different suggested threshold values is the age of the used populations. OBJECTIVE: The purpose of the study was to determine whether antigen specific IgE values could become the index of food allergy diagnosis in Japan and to determine the effect of different ages. METHODS: Children whose specific IgE against major food antigens (egg white, cow's milk, wheat and soy bean) were measured within six months after their first visit, were included in the study. The diagnosis of food allergy was made at the point of blood drawn, by firm episodes after the ingestion of those foods, or the results of food challenge tests. Specific IgE to the relevant antigen were measured using the Pharmacia CAP-System FEIA®. The total numbers of examination were; egg whites; 1025 subjects, milk; 458 subjects, wheat; 437 subjects, and soy bean; 422 subjects. The children were poststratfied into 6 age groups, < 0.5 year, 0.5-1 year, 1 year, 2 year, 3 year and 4 years of age. The specific IgE antibody concentrations were related ro the oucome using a logistic regression model. The estimated models were expressed as probabilities. Tests and confidence intervals were according to Wald, using a p value of 0.05 as significant. Computerised statistical analysis was performed using SAS System V8.01 Results: For each antigen a significant relationship between the probability of reacting to food and the specific IgE antibody concentrations could be found. When the population was post stratified for ages, different shapes of the probability curves were found. For egg white four significantly different relationships were found, indicating that for children of 1 year or younger even a very low concentration of specific IgE antibodies was associated with a rather high probability for reaction, the younger the child was the higher probability. The same pattern was found also for milk and wheat. CONCLUSIONS: Our results show that the age and the kinds of antigen are major factors when relating the specific IgE antibody concentration to the probability of reacting to food. They also make an explanation to the previously published different threshold values, indicating that age may explain the difference in threshold values.

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[213] - Scibilia J, Pastorello EA, Zisa G, Ottolenghi A, Bindslev-Jensen C, Pravettoni V, et al. Wheat allergy: A double-blind, placebo-controlled study in adults. J Allergy Clin Immunol 2006;117:433-439

BACKGROUND: Wheat is believed to be an uncommon cause of food allergy in adults; the number of studies that address IgE mediated wheat allergy in adults is all too few . OBJECTIVE: Determine how many subjects with a history of wheat allergy have real allergy by double-blind, placebo-controlled food challenge; identify the symptoms manifested during the challenge; determine the lowest provocation dose; determine the performance characteristics of wheat skin prick test and specific IgE; identify subjects with real wheat allergy for potential immunoblotting studies . METHODS: Patients underwent skin test with commercial wheat extract; specific wheat IgE was determined. Subjects were challenged with 25 g wheat. Subjects who were positive to raw wheat challenge underwent cooked wheat challenge . RESULTS: Thirty-seven double-blind placebo-controlled wheat challenges were performed on 27 patients. A total of 13 of 27 (48%) patients had a positive result. Eleven subjects with positive raw wheat challenge underwent cooked wheat challenge: 10 were positive. The provocation dose range was 0.1 to 25 g. Twenty-seven percent of the subjects allergic to wheat had a provocation dose that was < or =1.6 g . CONCLUSION: Wheat causes real food allergy in adults. More than a quarter of the patients allergic to wheat reacted to less than 1.6 g wheat. Specific IgE was more sensitive than skin test for wheat; however, specificity and predictive values were low for both tests. Thus, these tests should not be used to validate diagnosis of wheat allergy.

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[214] - Mehl A, Staden U, Beyer K, Niggemann B. Utility of the ratio of food-specific IgE / total IgE in predicting symptomatic food allergy in children. EAACI 23th Congress, Amsterdam, 12-16 June, 2004, Poster n°965

Background: Double blind, placebo controlled food challenges are time-consuming, expensive and not without risk. Therefore, a laboratory test that could accurately predict food allergy would be of great value. Objective: To evaluate the utility of the ratio of specific IgE / total IgE and its benefit compared to specific IgE alone in predicting symptomatic food allergy. Methods: 1202 controlled oral food challenges were performed in 468 children (median age 14 months). Sera were analyzed for concentrations of total IgE and food-specific IgE. The ratio of specific IgE / total IgE was calculated and tested for correlation with the outcome of food challenges. ROC-curves were performed; predicted probabilities and predictive decision points were calculated. Results: A significant correlation between the ratio and the outcome of food challenges was found for cow‚s milk (CM), hen‚s egg (HE) and wheat, but not for soy. ROC- and predicted probability curves as well as sensitivity and specificity of the decision points of the ratio were similar to those of specific IgE levels for CM and HE. For wheat, in contrast to specific IgE alone, the ratio reached a 95% predictied probability. Conclusion: Regarding the higher effort that has to be made for the ratio together with a missing benefit compared to the specific IgE, the determination of the ratio of specific IgE / total IgE for diagnosing symptomatic food allergy is senseless for CM, HE and soy. For wheat, the use of the ratio may be beneficial in selected cases. However, controlled oral food challenges remain the method of choice in the majority of children.

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[215] - Salvatori N, Reccardini F, Convento M, Purinan A, Colle R, De Carli S, et al. Asthma induced by inhalation of flour in adults with food allergy to wheat. Clin Exp Allergy 2008;38:1349-1356

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[216] - Moneret-Vautrin DA, Kanny G, Perrier P, Denery-Papini S, Morisset M, Leduc V, et al. Etude prospective 1999-2002 de l'allergie alimentaire à la farine de blé chez l'enfant et chez l'adulte, comparée à la maladie coeliaque. Association de DR1 à l'allergie chez l'enfant. Alim'Inter 2003;8:2-8

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[217] - Perry TT, Matsui EC, Conover-Walker MK, Wood RA. The relationship of allergen-specific IgE levels and oral food challenge outcome. J Allergy Clin Immunol 2004;114:144-149

Background Oral food challenges remain the gold standard for the diagnosis of food allergy. However, clear clinical and laboratory guidelines have not been firmly established to determine when oral challenges should be performed. Objective : We sought to determine the value of food-specific IgE levels in predicting challenge outcome. Method s : A retrospective chart review of 604 food challenges in 391 children was performed. All children had food-specific IgE levels measured by means of CAP-RAST before challenge. Data were analyzed to determine the relationship between food-specific IgE levels and challenge outcome, as well as the relationship between other clinical parameters and challenge outcome. Result s : Forty-five percent of milk challenges were passed compared with 57% for egg, 59% for peanut, 67% for wheat, and 72% for soy. Specific IgE levels were higher among patients who failed challenges than among those who passed (P .03 for each food). When seeking a specific IgE level at which a 50% pass rate could be expected, a cutoff level of 2 kUA/L was determined for milk, egg, and peanut. Data were less clear for wheat and soy. Coexistent eczema or asthma was associated with failed egg challenges, but other atopic disease was otherwise not associated with challenge outcome. Conclusions : Allergen-specific IgE concentrations to milk, egg, and peanut and, to a lesser extent, wheat and soy serve as useful predictors of challenge outcome and should be considered when selecting patients for oral challenge to these foods.

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[218] - Niggemann B, Celik-Bilgili S, Ziegert M, Reibel S, Sommerfeld C, Wahn U. Specific IgE levels do not indicate persistence or transience of food allergy in children with atopic dermatitis. J Investig Allergol Clin Immunol 2004;14:98-103

BACKGROUND: Food allergy in early childhood usually resolves with time; however, little is known about predictors for persistence or transience of food allergy in children with atopic dermatitis. The aim of the study was to evaluate whether specific IgE levels in serum could be a useful predictor of the outcome of oral re-challenges . METHODS: In 74 children, 99 oral food challenges were performed (cow milk n = 48, hen egg n = 37, and wheat n = 14) and repeated after a median time interval of 16 months. In 15 of the 74 children, a third challenge (n = 22) could be performed, with a median time interval from second challenge to third challenge of 15 months . RESULTS: There were 37 children with transient food allergy (positive first challenge and negative second challenge), while 62 children had persistent food allergy (positive first challenge and negative second challenge). Comparison of the two groups showed that specific IgE as well as total IgE in serum was significantly higher in the latter group. However, looking at the time course, specific IgE did not decrease significantly during elimination diet . CONCLUSION: Our results indicate that specific IgE in serum--although very helpful at the time of the first diagnosis--cannot predict whether a chid will become tolerant after a period of avoidance. Therefore, oral re-challenges remain mandatory.

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[219] - Takizawa T, Arakawa H, Tokuyama K, Morikawa A. Identification of allergen fractions of wheat flour responsible for anaphylactic reactions to wheat products in infants and young children. Int Arch Allergy Immunol 2001;125:51-56

Wheat is a food allergen which occasionally causes anaphylactic reactions exclusively in young children. There is very little knowledge of the clinical outcome in cases of food-related anaphylaxis and the differences in the allergenic protein components of food involved, comparing individuals who have suffered from an anaphylactic reaction with other individuals. The objectives of the present study were to examine the clinical features of 7 young children who had experienced anaphylactic reactions after ingesting wheat flour-containing products, and to analyze the allergens in wheat flour responsible for the anaphylactic symptoms. We measured the total IgE levels and the levels of IgE antibodies specific to wheat flour and performed IgE immunoblotting, comparing the sera from these children with sera from patients with atopic dermatitis. All sera from children who had experienced anaphylactic reactions were found to be positive for IgE specific to wheat. IgE immunoblotting revealed that 3 of these 7 children had sera showing reactivity to components of the salt-soluble protein fraction (16, 35--67 and 94 kD) and salt-insoluble protein-containing fraction (16, 38 and 70 kD) and 4 had no sera showing reactivity to components of the salt-soluble fraction. Patients with atopic dermatitis showed similar staining patterns. Various proteins in wheat flour could be allergens responsible for anaphylaxis and atopic dermatitis in infants or young children. Our findings suggest that these two clinically diverse allergic diseases do not necessarily represent responses to different allergenic proteins of wheat

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[220] - Sander I, Merget R, Degens PO, Goldscheid N, Brüning T, Raulf-Heimsoth M. Comparison of wheat and rye flour skin prick test solutions for diagnosis of baker’s asthma. Allergy 2004;59:95-98

BACKGROUND: Skin prick tests (SPTs) play an important role in the diagnosis of baker's asthma and in the investigation of sensitization frequencies in field studies. It was the aim of our study to compare different SPT solutions for wheat and rye flour sensitization and to assess the validity of test results . METHODS: Skin prick tests with wheat and rye flour were performed in parallel with extracts from different companies and compared with the results of bronchial challenge tests with both flours (69 rye flour and 51 wheat flour challenge tests). Additionally, specific immunoglobulin E (sIgE) to wheat and rye flour were tested. SPT solutions were analysed for protein content and by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) . RESULTS: Skin prick test solutions for diagnosis of wheat and rye flour sensitization from three companies differed in protein concentrations and composition with the consequence of widely differing SPT results. Sensitivity of SPTs in comparison with allergen-specific bronchial challenge as a gold standard was between 40 and 67%, specificity was between 86 and 100%, the positive predictive value (PPV) ranged from 81 to 100% and the negative predictive value (NPV) from 44 to 70%. These numbers were only marginally affected by using a combination of challenge test result and sIgE value as a more specific gold standard . CONCLUSION: Improvement and standardization of SPT extracts for wheat and rye flour is highly recommended.

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[221] - van Kampen V, Rabstein S, Sander I, Merget R, Brüning T, Broding HC, et al. Prediction of challenge test results by flour-specific IgE and skin prick test in symptomatic bakers. Allergy 2008;63:897-902

BACKGROUND: Wheat and rye flours are among the most important allergens causing occupational asthma. Usually, the diagnosis of baker's asthma is based on inhalation challenge tests with flours. AIMS OF THE STUDY: To evaluate the relevance of flour-specific serum immunoglobulin E (IgE) and skin prick test (SPT) in the diagnosis of baker's asthma and to define flour-specific IgE concentrations and wheal sizes that allow a prediction of the outcome of challenge testing . METHODS: Bronchial and nasal challenge tests with wheat (rye) flour were performed in 71 (95) symptomatic bakers. Determinations of flour-specific IgE as well as SPTs were performed in all subjects. Analyses included the calculation of sensitivity, specificity, positive (PPV) and negative predictive values (NPV) at different IgE concentrations and different wheal sizes, and receiver-operating characteristics (ROC) plots with the challenge result as gold standard . RESULTS: Thirty-seven bakers were positive in the challenge with wheat flour, while 63 were positive with rye flour. Depending on the flour-specific IgE concentrations (wheal size), PPV was 74-100% (74-100%) for wheat and 82-100% (91-100%) for rye flour, respectively. The minimal cut-off values with a PPV of 100% were 2.32 kU/l (5.0 mm) for wheat flour and 9.64 kU/l (4.5 mm) for rye flour. The shapes of the ROC plots were similar for wheat and rye flour . CONCLUSION: High concentrations of flour-specific IgE and clear SPT results in symptomatic bakers are good predictors for a positive challenge test. Challenge tests with flours may be avoided in strongly sensitized bakers.

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[222] - Laurière M, Bouchez I, Doyen C, Eynard L. Identification of glycosylated forms of wheat storage proteins using 2D electrophoresis and blotting. Electrophoresis 1996;17:497-501

Two-dimensional electrophoresis with acid-polyacrylamide gel electrophoresis (PAGE), followed by sodium dodecyl sulfate (SDS)-PAGE and SDS-PAGE of unreduced polypeptides followed by SDS-PAGE under reducing conditions, were used to separate and identify the different subgroups of gliadins and glutenins and to distinguish between covalent and noncovalent polymers of glutenins. Gels were blotted under semidry conditions according to Laurière (Anal. Biochem. 1993, 212, 206-211) to allow large polymers of glutenins to be transferred efficiently. Glycosylated polypeptides were detected on blots using either the method of Haselbeck and Hösel (Glycoconjugate J. 1990, 7, 63-74), or using anti-(xylose-containing N-glycan) antibodies (Laurière et al., Plant Physiol 1989, 90, 1182-1188). High and low molecular weight glutenin subunits were shown to aggregate through both disulfide bridges and noncovalent protein-to-protein interactions. Aggregated gamma-gliadins were also demonstrated. Glycans were detected on both gliadin and glutenin polypeptides. Covalently aggregated low molecular weight glutenins were shown to contain N-glycans with xylose, which demonstrated their sorting in the Golgi apparatus.

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[223] - Malandain H, Giroux F, Cano Y. The influence of carbohydrate structures present in common allergen sources on specific IgE results. Eur Ann Allergy Clin Immunol 2007;39:216-220

BACKGROUND: Cross-reactive carbohydrate determinants (CCD) are well known interferants in specific IgE assays (sIgE). Glyco-epitopes are not restricted to CCD and extracts used to prepare in vitro tests contain many other glycoproteins able to bind glycan-specific IgE. The overall amounts of IgE-bindable glycan structures in allergen sources are unknown . OBJECTIVE: We aimed at quantifying the influence of N-glycan structures on IgE reactivity to commonly tested allergen sources . METHODS: IgE reactivity to 51 allergen extracts, one purified natural allergen and 10 recombinant allergens was measured on Phadia UniCAP system using 2 sera demonstrating significant levels of glycan-related IgE reactivity. Immobilized bromelain and horseradish peroxidase (HRP) were used to capture N-glycan-specific IgE from these sera. Residual IgE reactivity was measured for 42 allergen sources and 4 recombinant/purified allergens . RESULTS: An obviously excessive number of positive CAP-results were obtained with both sera, especially for plant-based allergen sources. Capture of glycan-specific IgE led to a decrease of serum IgE ractivity, variable among allergen sources and between sera. Among others, peanut results were proven largely interfered by the presence of glycan-specific IgE. Unexpectedly some allergen sources showed a slight influence of glycan-related reactivity, such as cockroach, mosquito, mussel, shrimp and domestic mites . CONCLUSION: In patients sensitized to pollens or to Hymenoptera venoms sIgE results should be interpreted with caution. One cannot substract the result of a glyco-reporter test (bromelain and/or HRP) in order to compute glycan-free slgE results for common allergen sources like peanuts. As long as the demonstration of a significant role for glycan structures in clinical allergic reactions is lacking, a simple pre-treatment able to discard glycan-specific IgE from serum would be useful to improve accuracy of in vitro diagnostic tests.

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[224] - Pastorello EA, Farioli L, Conti A, Pravettoni V, Bonomi S, Iametti S, et al. Wheat IgE-Mediated Food Allergy in European Patients: alpha-Amylase Inhibitors, Lipid Transfer Proteins and Low-Molecular-Weight Glutenins Allergenic Molecules Recognized by Double-Blind, Placebo-Controlled Food Challenge. Int Arch Allergy Immunol 2007;144:10-22

BACKGROUND: Three main problems hamper the identification of wheat food allergens: (1) lack of a standardized procedure for extracting all of the wheat protein fractions; (2) absence of double-blind, placebo-controlled food challenge studies that compare the allergenic profile of Osborne's three protein fractions in subjects with real wheat allergy, and (3) lack of data on the differences in IgE-binding capacity between raw and cooked wheat . METHODS: Sera of 16 wheat-challenge-positive patients and 6 patients with wheat anaphylaxis, recruited from Italy, Denmark and Switzerland, were used for sodium dodecyl sulfate-polyacrylamide gel electrophoresis/immunoblotting of the three Osborne's protein fractions (albumin/globulin, gliadins and glutenins) of raw and cooked wheat. Thermal sensitivity of wheat lipid transfer protein (LTP) was investigated by spectroscopic approaches. IgE cross-reactivity between wheat and grass pollen was studied by blot inhibition . RESULTS: The most important wheat allergens were the alpha-amylase/trypsin inhibitor subunits, which were present in all three protein fractions of raw and cooked wheat. Other important allergens were a 9-kDa LTP in the albumin/globulin fraction and several low-molecular-weight (LMW) glutenin subunits in the gluten fraction. All these allergens showed heat resistance and lack of cross-reactivity to grass pollen allergens. LTP was a major allergen only in Italian patients . CONCLUSIONS: The alpha-amylase inhibitor was confirmed to be the most important wheat allergen in food allergy and to play a role in wheat-dependent exercise-induced anaphylaxis, too. Other important allergens were LTP and the LMW glutenin subunits.

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[225] - Battais F, Courcoux P, Popineau Y, Kanny G, Moneret-Vautrin DA, Denery-Papini S. Food allergy to wheat: differences in IgE binding proteins as a function of age and symptoms. J Cereal Sci 2005;42:109-117

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[226] - de Boissieu D, Dupont C. Dermatite atopique de l'enfant et allergie au blé. Rev Fr Allergol Immunol Clin 2005;45:411-415

La fréquence de l'allergie au blé au cours de la dermatite atopique de l'enfant est évaluée entre 14 et 18 %. Elle a la particularité de se manifester souvent par des réactions retardées, avec des manifestations cutanées ou digestives. Les réactions immédiates sévères semblent relativement rares. La négativité des pricks tests et des IgE spécifiques au blé n'éliminent pas le diagnostic. Le test épicutané à la farine de blé semble le meilleur examen de dépistage, mais est peu spécifique chez le très jeune enfant. Le diagnostic doit être confirmé par un test de provocation qui doit être prolongé sur plusieurs jours en raison de la fréquence des réactions retardées.

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[227] - Varjonen E, Vainio E, Kalimo K. Antigliadin IgE: indicator of wheat allergy in atopic dermatitis. Allergy 2000;55:386-391

BACKGROUND: Cereal grains are recognized as the cause of adverse reactions in some patients exposed to grain or flour by either inhalation or ingestion. Cereal-related diseases, such as celiac disease and baker's asthma, have been well studied and the causative cereal proteins have been characterized. Although cereals form an essential part of daily nutrition, the allergenic proteins causing symptoms on ingestion in atopic dermatitis (AD) have remained obscure. In this study, we have investigated the allergenic fraction of wheat in AD . METHODS: Skin prick tests (SPT) with a NaCl wheat suspension and the ethanol-soluble wheat gliadin were performed on 18 wheat-challenge-positive or -negative children with AD, six adult AD patients with suspected cereal allergy, and one adult with wheat-dependent exercise-induced urticaria/anaphylaxis. Serum total IgE and specific IgE-antibody levels to wheat and gluten were measured with the radioallergosorbent test (RAST) simultaneously. In addition serum samples of all 25 patients were analyzed by IgE immunoblotting with the ethanol-soluble wheat-protein extract . RESULTS: Thirteen of the AD children were wheat-challenge-positive, 11/12 of them appeared to be positive with gliadin SPT, and all had an elevated gluten RAST value. Those challenge-negative were negative with both gliadin SPT and gluten RAST. Positive wheat SPT and RAST alone were not associated with positive challenges. Four of the adult patients responded to a cereal-free diet, although only two of them appeared to be positive with gliadin SPT and gluten RAST. A broad and intensive staining of gliadin peptides in IgE-immunoblotting studies was seen in challenge-positive children with positive gliadin SPT and/ or gluten RAST. Besides staining of peptides in the main gliadin area of 30-46 kDa, a characteristic finding was the staining of small, <14-kDa proteins with sera of challenge- and gliadin-SPT-positive patients . CONCLUSIONS: We found that wheat-allergic AD patients have IgE antibodies against gliadin that can be detected by both SPT and the sensitive immunoblotting method. This suggests that gliadin peptides are important allergens, and ingestion of wheat causes symptoms of AD. A broad and intensive IgE staining was seen of gliadin peptides against both the previously characterized peptides in the main gliadin area and small, previously uncharacterized peptides of less than 14 kDa. The gliadin SPT and gluten RAST are good screening methods. Further characterization of the IgE-stained gliadin proteins is needed.

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[228] - Mittag D, Niggemann B, Sander I, Reese I, Fiedler EM, Worm M, et al. Immunoglobulin E-reactivity of wheat-allergic subjects (baker's asthma, food allergy, wheat-dependent, exercise-induced anaphylaxis) to wheat protein fractions with different solubility and digestibility. Mol Nutr Food Res 2004;48:380-389

Baker's asthma, food allergy to wheat, and wheat-dependent, exercise-induced anaphylaxis (WDEIA) are different clinical forms of wheat allergy. We investigated the correlation of solubility and digestion stability of wheat allergens with the IgE-reactivity patterns of different patient groups. Three wheat protein fractions were extracted according to their solubility: salt-soluble albumins and globulins, ethanol-soluble gliadins, and glutenins soluble only after treatment with detergents and reducing reagents. Sera from subjects with history of each variant of wheat allergy were characterized by CAP FEIA and immunoblotting. There was a high degree of heterogeneity of recognized allergens between the different subject groups as well as within these groups. However, subjects with WDEIA showed similar immunoglobulin E (IgE)-reactivity patterns to gliadins and especially to a 65 kDa protein. Subjects with baker's asthma as well as the food-allergic subjects had the most intense IgE-reactivity to the albumin/globulin fraction. The latter group additionally showed IgE-reactivity to the other fractions. Divergent results of immunoblotting and CAP-FEIA demonstrated that the detection of wheat-specific IgE highly depends on the applied method, thus the diagnostic tool must be carefully chosen. Most wheat allergens were rapidly digested as analyzed by determination of IgE-reactivity on immunoblots to wheat extracts after simulation of gastric and duodenal digestion. However, ethanol-soluble gliadins were stable to gastric enzymes and exhibit low solubility in gastric and duodenal fluids. Therefore, they are likely to be important in food allergy to wheat.

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[229] - Battais F, Pineau F, Popineau Y, Aparicio C, Kanny G, Guérin L, et al. Food allergy to wheat: identification of IgE- and IgG-binding proteins with sequential extracts and purified proteins from wheat flour. Clin Exp Allergy 2003;33:962-970

BACKGROUND: Cereal-associated allergy is particularly considered a serious problem, because cereals are essential in our daily diet. Wheat proteins are classified into albumins, globulins and prolamins (insoluble gliadins and glutenins) . OBJECTIVES: Our objectives were to study the involvement in food allergy to wheat of these different protein types by using purified fractions and to identify those binding IgE and IgG antibodies . METHODS: Sera were obtained from 28 patients with food allergy to wheat. Albumins/globulins, gliadins and glutenins were obtained by sequential extraction based on differential solubility; alpha-, beta-, gamma- and omega-gliadins and low molecular weight (LMW) and high molecular weight (HMW) glutenin subunits were purified by chromatography. IgE binding to these extracts and fractions were analysed by radioallergosorbent test (RAST), and immunoblotting; IgG binding was detected by enzyme-linked immunosorbent assay (ELISA) . RESULTS: In RAST, 60% of sera were shown to have specific IgE antibodies against alpha-, beta-gliadins and LMW glutenin subunits, 55% to gamma-gliadins, 48% to omega-gliadins and 26% to HMW glutenins. Immunoblotting analysis confirmed results obtained in RAST concerning LMW and HMW glutenin subunits and showed that 67% of patients have IgE antibodies to the albumin/globulin fraction . CONCLUSION: Results obtained in the different tests showed common features and in agreement with other studies indicated the presence of numerous allergens in food allergy to wheat; alpha-, beta-, gamma- and omega-gliadins, LMW glutenin subunits and some water/salt-soluble proteins appeared as major IgE binding allergens, whereas HMW glutenins were only minor allergens. The same type of antigenic profile against gliadins and glutenins was observed with IgG antibodies. Important sequence or structural homologies between the various gliadins and LMW glutenin subunits could certainly explain similarity of IgE binding to these proteins.

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[230] - Battais F, Courcoux P, Popineau Y, Kanny G, Moneret-Vautrin DA, Denery-Papini S. Food allergy to wheat: differences in IgE binding proteins as a function of age and symptoms. J Cereal Sci 2005;42:109-117

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[231] - Denery-Papini S, Lauriere M, Branlard G, Morisset M, Pecquet C, Choudat D, et al. Influence of the Allelic Variants Encoded at the Gli-B1 Locus, Responsible for a Major Allergen of Wheat, on IgE Reactivity for Patients Suffering from Food Allergy to Wheat. J Agric Food Chem 2007;55:799-805

Wheat presents an important genetic diversity that could be useful to look for cultivars with reduced allergencity. omega5-Gliadins have been described as major allergens for wheat allergic patients suffering from wheat-dependent exercise-induced anaphylaxis (WDEIA) and some cases of chronic urticaria (U). Our objective was to study the influence of genetic variability at the Gli-B1 locus encoding for omega5-gliadins on the reactivity of IgE antibodies from these patients. We selected cultivars expressing 13 alleles at Gli-B1 including a wheat/rye translocation and studied the reactivity to gliadins of a rabbit antiserum specific for omega5-gliadins and of IgE from 10 patients. The antiserum and IgE from nine patients with WDEIA and U strongly detected omega5-gliadins expressed by most of the Gli-B1 alleles but showed no or faint responses to the gliadins and secalins extracted from the translocated wheat. The selection of genotypes lacking the Gli-B1 locus may reduce wheat allergenicity. Keywords: Wheat; food allergy; exercise induced anaphylaxis; omega5-gliadins; allelic variants.

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[232] - Battais F, Courcoux P, Popineau Y, Kanny G, Moneret-Vautrin DA, Denery-Papini S. Food allergy to wheat: differences in IgE binding proteins as a function of age and symptoms. J Cereal Sci 2005;42:109-117

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[233] - Soeria-Atmadja D, Eriksson C, Turjanmaa K, Hammerling U, Önell A, Holmquist I, et al. A supervised learning approach to identify potentially useful components in wheat allergy diagnosis. Allergy 2008;63(suppl. 88):135-136

Background: In the clinic it is often difficult to tell, without challenge, whether IgE sensitisation to wheat reflects a food allergy or not. The aim of this study was to evaluate the applicability of a range of components and protein fractions with a potential of being useful for the clinical diagnosis of wheat allergy. Subjects: Serum samples were collected from 65 children, with ages ranging from 3 months to 7 years, all challenged with wheat. Provocation separated test subjects into two clinical groups: A) children with acute symptoms (n526) and B) children either without symptoms or those of delayed type (n539). Methods: Gliadins and water soluble proteins were purified according to standard procedures. The fractionated proteins were immobilized in triplicates onto a capillary flow membrane. In total, specific IgE abs to 30 proteins/fractions were recorded for each patient using an anti-IgE ab conjugated to a fluorescent marker. To identify a potentially discriminative set of proteins/fractions, supervised multivariate data analysis was performed on the array data according to the following protocol:1. Randomised division of subjects in a training set for model building and a test set2. Supervised identification of the protein/fraction combination that best discriminates between groups in the training set3. Design of a supervised classifier with training set using best protein combination4. Evaluation of predictive performance of classifier using the test set5. Evaluation of robustness by repeating step 1ˆ4 50 times with varying selection of patients in training/test sets. Results: Frequencies of proteins occurring in combinations that best discriminated between groups A and B over 50 iterations were recorded. Eleven of the components/ fractions were never selected in this process and 10 had a low frequency range (2ˆ10%). Those of highest occurrence frequencies were timothy allergen Phl p 4, a marker for cross-reactive carbohydrate determinant (CCD) and wheat a-Amylase inhibitor 2. Average sensitivity and specificity over 50 iterations was 64% and 76%, respectively. Conclusion: Clearly, analysis of multivariate data generated from protein micro arrays needs specialized computational methods. The presented methodology seems useful for discarding components with limited clinical importance. More test subjects are, however, needed to identify single or combinations of components for a robust prediction of wheat allergy.

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[234] - Mittag D, Niggemann B, Sander I, Reese I, Fiedler EM, Worm M, et al. Immunoglobulin E-reactivity of wheat-allergic subjects (baker's asthma, food allergy, wheat-dependent, exercise-induced anaphylaxis) to wheat protein fractions with different solubility and digestibility. Mol Nutr Food Res 2004;48:380-389

Baker's asthma, food allergy to wheat, and wheat-dependent, exercise-induced anaphylaxis (WDEIA) are different clinical forms of wheat allergy. We investigated the correlation of solubility and digestion stability of wheat allergens with the IgE-reactivity patterns of different patient groups. Three wheat protein fractions were extracted according to their solubility: salt-soluble albumins and globulins, ethanol-soluble gliadins, and glutenins soluble only after treatment with detergents and reducing reagents. Sera from subjects with history of each variant of wheat allergy were characterized by CAP FEIA and immunoblotting. There was a high degree of heterogeneity of recognized allergens between the different subject groups as well as within these groups. However, subjects with WDEIA showed similar immunoglobulin E (IgE)-reactivity patterns to gliadins and especially to a 65 kDa protein. Subjects with baker's asthma as well as the food-allergic subjects had the most intense IgE-reactivity to the albumin/globulin fraction. The latter group additionally showed IgE-reactivity to the other fractions. Divergent results of immunoblotting and CAP-FEIA demonstrated that the detection of wheat-specific IgE highly depends on the applied method, thus the diagnostic tool must be carefully chosen. Most wheat allergens were rapidly digested as analyzed by determination of IgE-reactivity on immunoblots to wheat extracts after simulation of gastric and duodenal digestion. However, ethanol-soluble gliadins were stable to gastric enzymes and exhibit low solubility in gastric and duodenal fluids. Therefore, they are likely to be important in food allergy to wheat.

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[235] - Battais F, Courcoux P, Popineau Y, Kanny G, Moneret-Vautrin DA, Denery-Papini S. Food allergy to wheat: differences in IgE binding proteins as a function of age and symptoms. J Cereal Sci 2005;42:109-117

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[236] - Bouchez-Mahiout I, Tylichova M, Snégaroff J, Pecquet C, Branlard G, Laurière M. Diversité de la réactivité des IgE vis à vis des protéines du blé dans l'anaphylaxie au blé induite par l'effort. Rev Fr Allergol Immunol Clin 2008;48:275

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[237] - Battais F, Courcoux P, Popineau Y, Kanny G, Moneret-Vautrin DA, Denery-Papini S. Food allergy to wheat: differences in IgE binding proteins as a function of age and symptoms. J Cereal Sci 2005;42:109-117

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[238] - Snégaroff J, Branlard G, Bouchez-Mahiout I, Laudet B, Tylichova M, Chardot T, et al. Recombinant Proteins and Peptides as Tools for Studying IgE Reactivity with Low-Molecular-Weight Glutenin Subunits in Some Wheat Allergies. J Agric Food Chem 2007;55:9837-9845

Two genes of wheat low-molecular-weight glutenin subunits (LMW-GS), B16 and P73, were cloned and expressed in E. coli. They were homologous to proteins encoded respectively at Glu-B3 and Glu-D3 loci. The N-terminal and C-terminal halves of B16 (NB16 and B16C) and the two chimeras combining the halves of the two genes (B16-P73 and P73- B16) were also expressed. All these constructs were compared for their reactivity with IgE from 24 patients suffering from different forms of wheat allergies. The results confirmed that LMW-GSs bound IgE in all adult allergies tested. Strong differences in reactivity between all the constructs were observed. They were disease-dependent. In wheat-dependent exercise-induced anaphylaxis (WDEIA), the reactivity of the constructs depended partly on common epitopes with omega-5 gliadins but also on differences in molecule conformation. The presence of NB16 in the constructs greatly influenced their IgE reactivity.

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[239] - Weichel M, Glaser AG, Ballmer-Weber BK, Schmid-Grendelmeier P, Crameri R. Wheat and maize thioredoxins: A novel cross-reactive cereal allergen family related to baker's asthma. J Allergy Clin Immunol 2006;117:676-681

BACKGROUND: Baker's asthma is a serious problem for a significant proportion of workers in bakeries, confectionaries, and the food industry. Although several wheat allergens related to baker's asthma have been described, standardized reagents for a reliable diagnosis are not yet available . OBJECTIVE: To clone novel wheat allergens related to baker's asthma and investigate the cross-reactive potential of their maize and human homologues . METHODS: A wheat cDNA phage display library was screened with sera from bakers with occupational asthma for IgE-binding structures. Homologous sequences from maize and human thioredoxins were amplified from corresponding cDNA libraries . RESULTS: Within the enriched wheat cDNA repertoire we identified, among others, the sequence encoding wheat thioredoxin-hB (Triticum aestivum allergen 25 [Tri a 25]). The recombinant protein displayed enzymatic activity, and we observed a sensitization rate of 47% among bakers with occupational asthma and of 35% among patients with grass pollen allergy, but without a clinical history of cereal allergy. Furthermore, the previously characterized maize thioredoxin-h1 (Zea mays allergen 25 [Zea m 25]), sharing 74% identity with Tri a 25, exhibited distinct IgE cross-reactivity with its wheat homologue. Two bakers also showed sensitization to human thioredoxin, which shares 29% identity with Tri a 25. In a comparative study, we included recombinant alpha-amylase inhibitor 0.19, showing a sensitization rate of 65% in individuals with baker's asthma . CONCLUSION: Thioredoxins represent a novel family of cross-reactive allergens that might contribute to the symptoms of baker's asthma and might in addition be related to grass pollen allergy, as indicated by the reactivity of grass pollen allergic patients to cereal thioredoxins. CLINICAL IMPLICATIONS: The recombinant cereal thioredoxins will, together with the already reported wheat allergens, contribute to a more reliable diagnosis of baker's asthma and, perhaps, become a tool for the development of component-resolved immunotherapy.

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[240] - Bouchez-Mahiout I, Snégaroff J, Boulenc E, Pecquet C, Choudat D, Raison-Peyron N, et al. Spécificité des protéines impliquées dans différentes formes d’allergie au blé. Rev Fr Allergol Immunol Clin 2007;47:285

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[241] - Bittner C, Grassau B, Frenzel K, Baur X. Identification of wheat gliadins as an allergen family related to baker’s asthma. J Allergy Clin Immunol 2008;121:744-749

BACKGROUND: Flour is still one of the most common causes of occupational asthma worldwide. Thus far, little is known about the relevant allergens causing baker's asthma. Therefore the reliability of current diagnostic procedures is insufficient. Only few of the suspected causative wheat allergens have been hitherto characterized on the molecular level . OBJECTIVE: The aim was to identify and characterize unknown wheat allergens related to baker's asthma to improve the reliability of diagnostic procedures . METHODS: A wheat pJuFo cDNA phage display library was created and screened for IgE binding to wheat proteins with pooled sera from patients with baker's asthma. After identifying an alphabeta-gliadin, the frequency of sensitization was investigated by means of ELISA screening of 153 bakers' sera with the recombinant alphabeta-gliadin. Furthermore, the allergenicity of native total gliadin (alphabeta, gamma, omega) was analyzed by means of ImmunoCAP . RESULTS: One cDNA clone was identified as an alphabeta-gliadin. Serum IgE antibodies to the recombinant allergen were found in 12% of bakers with occupational asthma. Of the asthmatic bakers, 33% showed sensitization to native total gliadin; 4% of them had negative results on routine IgE testing with wheat extract . CONCLUSIONS: Gliadins represent a newly discovered family of inhalable allergens in baker's asthma. This finding demonstrates that water-insoluble proteins might also represent causative allergens.

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[242] - Matsuo H, Kohno K, Morita E. Molecular cloning, recombinant expression and IgE-binding epitope of omega-5 gliadin, a major allergen in wheat-dependent exercise-induced anaphylaxis. FEBS J 2005;272:4431-4438

Wheatomega-5 gliadin has been identified as a major allergen in wheat-dependent exercise-induced anaphylaxis. We have detected seven IgE-binding epitopes in primary sequence of the protein. We newly identified four additional IgE-binding epitope sequences, QQFHQQQ, QSPEQQQ, YQQYPQQ and QQPPQQ, in three patients with wheat-dependent exercise-induced anaphylaxis in this study. Diagnosis and therapy of food allergy would benefit from the availability of defined recombinant allergens. However, because omega-5 gliadin gene has not been cloned, recombinant protein is currently unavailable. We sought to clone the omega-5 gliadin gene and produce the homogeneous recombinant protein for use in an in vitro diagnostic tool. Using a PCR-based strategy we isolated two full-length omega-5 gliadin genes, designated omega-5 and omega-5b, from wheat genomic DNA and determined the nucleotide sequences. The protein encoded by omega-5a was predicted to be 439 amino acids long with a calculated mass of 53 kDa; the omega-5b gene would encode a 393 amino acid, but it contains two stop codons indicating that omega-5b is pseudogene. The C-terminal half (178 amino acids) of the omega-5a gliadin protein, including all 11 IgE-binding epitope sequences, was expressed in Escherichia coli by means of the pET system and purified using RP-HPLC. Western blot analysis and dot blot inhibition assay of recombinant and native omega-5 gliadin purified from wheat flour demonstrated that recombinant protein had IgE-binding ability. Our results suggest that the recombinant protein can be a useful tool for identifying patients with wheat-dependent exercise-induced anaphylaxis in vitro.

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[243] - Battais F, Courcoux P, Popineau Y, Kanny G, Moneret-Vautrin DA, Denery-Papini S. Food allergy to wheat: differences in IgE binding proteins as a function of age and symptoms. J Cereal Sci 2005;42:109-117

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[244] - Palosuo K, Alenius H, Varjonen E, Koivuluhta M, Mikkola JH, Keskinen H, et al. A novel wheat gliadin as a cause of exercise-induced anaphylaxis. J Allergy Clin Immunol 1999;103:912-917

BACKGROUND: Food-dependent, exercise-induced anaphylaxis is a severe form of allergy; the reaction is caused by ingestion of a specific food before exercise. This disorder often escapes diagnosis because neither the ingested food nor the exercise alone induces the symptoms. OBJECTIVE: The aim of the study was to characterize the allergens involved in wheat-dependent, exercise-induced anaphylaxis and to describe the clinical outcome in a series of 18 adult patients. METHODS: All 18 patients had experienced recurrent episodes of generalized urticaria during exercise, 17 patients in association with collapse and 15 patients with an anaphylactic reaction. The symptoms appeared only when the patients had eaten food containing wheat before exercise. Wheat allergens were detected by immunoblotting, purified by gel filtration and reversed-phase chromatography, and subjected to N-terminal sequencing. The IgE-binding ability of the purified proteins was studied by ELISA, and their in vivo reactivity was studied by skin prick testing. RESULTS: IgE antibodies from pooled patient sera were bound to 65-kd and 40-kd wheat proteins in immunoblotting. The 65-kd allergen was a previously undescribed wheat protein, showing 61% sequence identity to gamma-gliadin, whereas the 40-kd allergen had 100% identity to alpha-gliadin. In ELISA, all 18 patients showed elevated IgE levels to the novel gamma-like gliadin, and 13 of the patients showed elevated IgE levels to the alpha-gliadin. None of the 54 control subjects with wheat allergy, urticaria, or coeliac disease had IgE antibodies to the gamma-like gliadin. The in vivo reactivity of the gamma-like gliadin was verified by positive skin prick test responses in all of the 15 patients who were tested. During the follow-up on a gluten-free or wheat-free diet, 3 patients experienced reactions after having unknowingly eaten wheat before exercise, but all the other patients who were adhering to the diet remained symptom-free. CONCLUSION: This study shows that wheat is a frequent cause of food-dependent, exercise-induced anaphylaxis and suggests that the major allergen is a previously undescribed gamma-like gliadin. For screening of this life-threatening allergy, we recommend skin prick testing with crude gliadin and we recommend a gluten-free diet for treatment.

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[245] - Ledent C, Mairesse M. Urticaire par allergie alimentaire induite par l'exercice: intérêt du dosage des IgEs oméga 5 gliadine et isolats de blé. Rev Fr Allergol Immunol Clin 2008;48:272-273

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[246] - Le Corre Y, Drouet M, Nicolie B, Bonneau JC, Leclère JM, Beauvillain C. Anaphylaxie induite par l'exercice au blé (AIE-blé): rôle du Saccharomyces ? Rev Fr Allergol Immunol Clin 2008;48:274

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[247] - Bouchez-Mahiout I, Tylichova M, Snégaroff J, Pecquet C, Branlard G, Laurière M. Diversité de la réactivité des IgE vis à vis des protéines du blé dans l'anaphylaxie au blé induite par l'effort. Rev Fr Allergol Immunol Clin 2008;48:275

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[248] - Matsuo H, Dahlström J, Kohno K, Takahashi H, Morita E. IgE Reactivity to Recombinant Omega-5 Gliadin in Wheat-Dependent Exercise-Induced Anaphylaxis. J Allergy Clin Immunol 2007;119(1 suppl):S30

RATIONALE: Since the measurement of IgE specific to wheat grain or gluten is not reliable test for diagnosing wheat-dependent exercise-induced anaphylaxis (WDEIA), we investigated the usefulness of measurement of IgE to recombinant omega-5 gliadin (rO5-glia) for identification of patients with WDEIA. METHODS: Fifty patients with WDEIA, 25 healthy subjects and 25 patients with atopic dermatitis who had wheat grain-specific IgE without experience of allergic reactions to wheat products were enrolled in this study. The C-terminal half (178 amino acids) of omega-5 gliadin was produced in E. coli and Pep A (KPQQQSPQQQFPQQQIPQQQ) from omega-5 gliadin and Pep B (PTSPQQSGQGQQPGQGQQ) from high molecular weight glutenin were chemically synthesized. Specific IgE to rO5-glia, Pep A and Pep B were measured with ImmunoCAP˙ (Phadia, Uppsala, Sweden). RESULTS: Forty of 50 patients with WDEIA had specific IgE to rO5-glia and 38 had IgE to Pep A, whereas 24 and 28 had IgE to wheat grain and gluten, respectively. Ten of 50 patients with WDEIA had specific IgE to Pep B and 7 of them had no specific IgE to either rO5-glia or Pep A. Eight, 4 and 10 of 25 patients with atopic dermatitis had IgE to rO5-glia, Pep A and Pep B, respectively, but the serum levels were low. None of the healthy controls had IgE to any of the tests. CONCLUSIONS: Measurements of specific IgE to rO5-glia, Pep A and Pep B are useful compared to that of wheat grain or gluten-specific IgE to identify patients with WDEIA.

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[249] - Matsuo H, Dahlstrom J, Tanaka A, Kohno K, Takahashi H, Furumura M, et al. Sensitivity and specificity of recombinant omega-5 gliadin-specific IgE measurement for the diagnosis of wheat-dependent exercise-induced anaphylaxis. Allergy 2008;63:233-236

BACKGROUND: A recent study has shown that the measurement of specific IgE antibodies to B-cell epitope peptides of wheat omega-5 gliadin (Pep A) and high molecular weight glutenin subunit (Pep B) are useful to diagnose wheat-dependent exercise-induced anaphylaxis (WDEIA). AIMS OF THE STUDY: We sought to compare the sensitivity and specificity of the in vitro tests for measuring the specific IgE antibodies to recombinant omega-5 gliadin (romega-5 gliadin) with those for wheat, gluten, Pep A, and Pep B in identification of patients with WDEIA . METHODS: Fifty patients with WDEIA, 25 healthy subjects and 25 patients with atopic dermatitis with specific IgE antibodies to wheat but without experience of allergic reactions after ingestion of wheat products were enrolled in this study. The concentrations of specific IgE antibodies were measured using ImmunoCAP. The empirical receiver operating characteristics curves (ROC) for each test were prepared and the areas under the ROC curve (AUC) were compared . RESULTS: In patients with WDEIA, the sensitivities of the allergen-specific IgE tests for wheat, gluten, Pep A, Pep B and romega-5 gliadin were 48%, 56%, 76%, 22%, and 80%, respectively. The seven of 10 WDEIA patients with no specific IgE antibodies to romega-5 gliadin had specific IgE antibodies to Pep B. The highest AUC (0.850) was observed in the test for romega-5 gliadin . CONCLUSIONS: Measuring the concentration of specific IgE antibodies to romega-5 gliadin is more useful than to wheat, gluten, or Pep A in the identification of patients with WDEIA.

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[250] - Palosuo K, Varjonen E, Kekki OM, Klemola T, Kalkkinen N, Alenius H, et al. Wheat omega-5 gliadin is a major allergen in children with immediate allergy to ingested wheat. J Allergy Clin Immunol 2001;108:634-638

Sensitization to wheat by ingestion can lead to food allergy symptoms and wheat-dependent, exercise-induced anaphylaxis. Sensitization by inhalation causes bakers' asthma and rhinitis. Wheat allergens have been characterized at the molecular level in bakers' asthma and in wheat-dependent, exercise-induced anaphylaxis, in which omega-5 gliadin (Tri a 19) is a major allergen. However, little information is available regarding allergens responsible for hypersensitivity reactions to ingested wheat in children. OBJECTIVE: The aim of this study was to examine whether children with allergy to ingested wheat have IgE antibodies to omega-5 gliadin. METHODS: Sera were obtained from 40 children (mean age, 2.5 years; range, 0.7-8.2 years) with suspected wheat allergy who presented with atopic dermatitis and/or gastrointestinal and/or respiratory symptoms. Wheat allergy was diagnosed with open or double-blinded, placebo-controlled oral wheat challenge. Wheat omega-5 gliadin was purified by reversed-phase chromatography, and serum IgE antibodies to omega-5 gliadin were measured by means of ELISA. In vivo reactivity was studied by skin prick testing. Control sera were obtained from 22 children with no evidence of food allergies. RESULTS: In oral wheat challenge, 19 children (48%) reacted with immediate and 8 children (20%) with delayed hypersensitivity symptoms. Sixteen (84%) of the children with immediate symptoms had IgE antibodies to purified omega-5 gliadin in ELISA. In contrast, IgE antibodies to omega-5 gliadin were not detected in any of the children with delayed or negative challenge test results or in the control children. The diagnostic specificity and positive predictive value of omega-5 gliadin ELISA were each 100% for immediate challenge reactions. Skin prick testing with omega-5 gliadin was positive in 6 of 7 children with immediate challenge symptoms and negative in 2 children with delayed challenge symptoms. CONCLUSION: The results of this study show that omega-5 gliadin is a significant allergen in young children with immediate allergic reactions to ingested wheat. IgE testing with omega-5 gliadin could be used to reduce the need for oral wheat challenges in children.

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[251] - Shibata R, Nishima S, Kohno K, Morita E, Matsuo H, Tanaka A. Specific IgE Antibodies To omega-5 Gliadin-Indicator Of Wheat Anaphylaxis And Its Tolerance In Wheat Sensitized Children. J Allergy Clin Immunol 2007;119(1 suppl):S120

RATIONALE: Wheat is one of the common food allergens and sometimes induces anaphylaxis in infantile atopic dermatitis with high wheat-specific IgE. The diagnostic role of omega-5 gliadin specific IgE antibodies in patients with wheat-dependent excise-induced anaphylaxis has been demonstrated. OBJECTIVE: The aim of this study was to identify the specific IgE antibodies to omega -5 gliadin and synthetic combined epitope peptides A and B for children with wheat hypersensitivity and tolerance confirmed by challenge test. PATIENTS AND METHODS: Forty eight wheat allergy patients (mean age 3.2 years old) were enrolled. Wheat allergy was confirmed by wheat specific IgE and challenge test with wheat noodles. Specific IgE antibody to wheat, gluten, omega -5 gliadin, peptide A and B were measured by CAP-system. RESULTS: Patients with wheat anaphylaxis showed significantly higher levels (~37 UA/ml) of omega-5 gliadin specific IgE than those with local urticaria and atopic eczema. In contrast, 80% of challenge negative patients did not indicate omega -5 gliadin specific IgE. In follow up cases of 16 wheat hypersensitivity the omega -5 gliadin IgE antibodies were significantly decreased to undetectable levels after tolerance by confirmed challenge, although wheat and gluten IgE antibodies were persistent at the positive levels. Specific IgE antibodies to peptide A were also detected at low levels in patients with wheat anaphylaxis but peptide B IgE were did not identified. CONCLUSIONS: Measurement of IgE levels specific to omega -5 gliadin is useful as a prediction of wheat-induced anaphylaxis and its tolerance.

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[252] - Dahlström J, Halvorsen R, Matsuo H, Kohno K, Morita E. IgE antibodies to recombinant omega-5 gliadin in children with severe reactions to wheat. EAACI 25th Congress, Vienna, 10-14 June, 2006, Poster n°1504

Background Wheat is a staple food in the western world and thus it is of great importance to identify patients at risk of having severe allergic reactions to wheat. IgE sensitisation to wheat is common among food allergic patients, but does not always correlate with allergic symptoms. Oral food challenge is today the only way to identify patients with clinical symptoms to wheat. However, food challenges are often inconvenient and a potential risk for the patients. Therefore, more reliable in vitro tests are needed. Here we describe the use of three wheat allergen components to identify patients suffering from immediate severe reactions when ingesting wheat. Subjects Thirty children (9 month to 8 years old) with IgE antibodies (IgE ab) to wheat grain, gluten and gliadin, suspected of having allergic symptoms to wheat were referred to Voksentoppen, Oslo, for further clinical investigation and oral challenge. Fourteen of the children reacted when challenged with wheat whereas 16 were asymptomatic (but reacted to other foods than wheat). Forty healthy control subjects were included in the study. Methods Allergen specific and total IgE was measured with ImmunoCAPTM (Phadia AB, Uppsala, Sweden). The C-terminal part of omega-5 gliadin (rO5-glia) was expressed in E.coli by the pET system and purified using RP-HPLC and Pep A from O5-glia and Pep B from HMW glutenin, were synthesized. The rO5-glia, Pep A and Pep B were conjugated to individual ImmunoCAP. Results All 30 patients, both the 14 symptomatic and the 16 asymptomatic, had IgE ab to wheat grain, gluten and gliadin. Eleven of the 14 symptomatic children had conciderable levels of IgE ab to rO5-glia (1-35 kU/L), 10/14 to Pep A (0.48-16 kU/L) and 2/14 to Pep B . Among the children with severe general reactions to wheat 9/10 patients had IgE ab to rO5-glia and 9/10 to Pep A and only 2/10 to Pep B. Of the asymptomatic children only 3/16 had low levels of IgE ab to rO5-glia (0.48-1.8 kU/L) and 2/16 (0.38 - 0.63 kU/L) to Pep A and 1/16 to Pep B. None of the healthy controls had IgE ab to any of the tests. Conclusion Measurement of IgE ab to recombinant omega-5 gliadin and Peptide A are very good complements to the measurements of IgE ab to wheat grain, gluten and gliadin to identify children at risk of having severe immediate reactions after intake of wheat containing foods.

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[253] - Ito K, Takaoka Y, Futamura M, Sakamoto T, Kohno K, Morita E, et al. Omega-5-Gliadin Specific IgE as a Predictor of Wheat Allergy in Children. J Allergy Clin Immunol 2007;119(1 suppl):S191

RATIONALE: Wheat is the third-most common food allergen in Japanese children, but detection of wheat-specific IgE antibody is insufficient to diagnose wheat allergy because of low clinical specificity. Omega-5-gliadin is known to represent a major allergen in wheat-dependent exercise-induced anaphylaxis, but levels in immediate-type wheat allergy in children remain unclear. METHODS: IgE antibody to omega-5-gliadin was detected by ImmunmoCAP in sera from patients with wheat allergy (n=44; mean age, 3.4 years) diagnosed according to positive wheat challenge or apparent clinical history. Control patients (n=44; mean age, 4.9 years) with positive IgE for wheat (>=3.5 UA/ml) but without clinical symptoms after ingestion of wheat products were also recruited. RESULTS: Levels of wheat-specific IgE (mean ±SD) were 44.52 ±36.37 UA/ml in patients and 12.57 ±11.81 UA/ml in controls. Omega-5-gliadin-specific IgE was positive (>0.34 UA/ml) in 37 patients with wheat allergy (84.1%) and 12 controls(27.3%). Mean IgE titer in positive sera was 7.25 UA/ml in patients (range, 0.40-81.0 UA/ml) and 1.08 UA/ml in controls (0.35-4.80 UA/ml). Although only 1 control patient showed a level of 4.80 UA/ml (all others were <1.30 UA/ml), 100% positive predictive value was obtained using a cutoff of >5.0 UA/ml. Patients with high IgE titer to omega-5-gliadin tended to display severe reactions including respiratory symptoms or anaphylaxis. CONCLUSIONS: Detection of omega-5-gliadin-specific IgE is useful for the diagnosis of immediate-type wheat allergy in children comparing to that of wheat.

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[254] - Dahlström J, Ito K, Shibata R, Borres M, Matsuo H, Kohno K, et al. Omega-5 gliadin in the diagnosis of children with wheat allergy. Allergy 2007;62(suppl. 83):104

Background: Wheat is a staple food in the western world and thus it is of great importance to identify patients at risk of having severe allergic reactions to wheat. IgE sensitization to wheat is common among food allergic patients, but does not always correlate with allergic symptoms. Measurement of IgE to omega-5 gliadin has been reported useful in detecting patients with exercise induced symptoms to wheat. Moreover, children with immediate reactions are reported to have IgE to omega-5 gliadin. Here we report the usage of omega-5 gliadin to identify children suffering from immediate reactions when ingesting wheat. Subjects: There were 126 wheat sensitised children (1 to 15 years old) enrolled in the study. Among theese 71 children reacted when challenged with wheat or had a strong convincing clinical history of allergy to wheat and 55 children had no symptoms or had a negative challenge to ingested wheat. Methods: Allergen specific IgE antibodies were measured with ImmunoCAPTM (Phadia AB, Uppsala, Sweden). The C-terminal part of omega-5 gliadin (rO5-glia) was expressed in E.coli by the pET system, purified using RP-HPLC and conjugated to ImmunoCAP. Results: All 126 patients were sensitized to wheat, both the 71 children with symptoms and the 55 children having no symptoms when ingesting wheat. In the group of patients having clinical symptoms when ingesting wheat 61/71 (86%) had elevated levels of IgE to rO5-glia (0.40-81 kUA/L). Among the patients having no clinical symptoms when ingesting wheat, although sensitized to wheat, only 13/55 (23.6%) had IgE to rO5-glia (0.39-4.8 kUA/L). In this study the sensitivity was 86% and the specificity was 76% for the test. Conclusion: Measurement of IgE ab to omega-5 gliadin in wheat sensitized children is very useful to identify children at risk of developing immediate clinical symptoms after intake of wheat containing foods.

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[255] - Paty E, Sheinmann P. Anaphylaxie à la farine de blé chez l'enfant. Rev Fr Allergol Immunol Clin 2008;48:287

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[256] - Daengsuwan T, Palosuo K, Phankingthongkum S, Visitsunthorn N, Jirapongsananuruk O, Alenius H, et al. IgE antibodies to omega-5 gliadin in children with wheat-induced anaphylaxis. Allergy 2005;60:506-509

Background: Wheat can cause severe immunoglobulin E (IgE)-mediated systemic reactions including anaphylaxis but knowledge on relevant wheat allergens at the molecular level is scanty. Methods: Seven children (aged from 6 months to 13 years) experiencing from 2 to 10 anaphylactic reactions in a year after eating food-containing wheat were examined. Purified omega-5 gliadin was used as an allergen in IgE enzyme-linked immunosorbent assay (ELISA) and in skin prick testing (SPT). Wheat CAP radioallergosorbent test (RAST) and SPT were also examined. Results: All seven anaphylactic children, but none of 15 control subjects had IgE antibodies to omega-5 gliadin in ELISA. Five of the six tested anaphylactic children showed positive SPT to omega-5 and crude gliadin, and all seven had positive wheat CAP RAST and SPT. One child was challenged with wheat, which caused anaphylaxis. After adherence to a wheat-free diet four children remained symptomless and three experienced one to two anaphylactic reactions. Conclusion: The present results show that wheat omega-5 gliadin is a major sensitizing allergen in children with wheat-induced anaphylaxis. They also suggest that omega-5 gliadin IgE ELISA could be used as a diagnostic test for this severe allergy.

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[257] - Denery-Papini S, Lauriere M, Branlard G, Morisset M, Pecquet C, Choudat D, et al. Influence of the Allelic Variants Encoded at the Gli-B1 Locus, Responsible for a Major Allergen of Wheat, on IgE Reactivity for Patients Suffering from Food Allergy to Wheat. J Agric Food Chem 2007;55:799-805

Wheat presents an important genetic diversity that could be useful to look for cultivars with reduced allergencity. omega5-Gliadins have been described as major allergens for wheat allergic patients suffering from wheat-dependent exercise-induced anaphylaxis (WDEIA) and some cases of chronic urticaria (U). Our objective was to study the influence of genetic variability at the Gli-B1 locus encoding for omega5-gliadins on the reactivity of IgE antibodies from these patients. We selected cultivars expressing 13 alleles at Gli-B1 including a wheat/rye translocation and studied the reactivity to gliadins of a rabbit antiserum specific for omega5-gliadins and of IgE from 10 patients. The antiserum and IgE from nine patients with WDEIA and U strongly detected omega5-gliadins expressed by most of the Gli-B1 alleles but showed no or faint responses to the gliadins and secalins extracted from the translocated wheat. The selection of genotypes lacking the Gli-B1 locus may reduce wheat allergenicity. Keywords: Wheat; food allergy; exercise induced anaphylaxis; omega5-gliadins; allelic variants.

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[258] - Lehto M, Palosuo K, Varjonen E, Majuri ML, Andersson U, Reunala T, et al. Humoral and cellular responses to gliadin in wheat-dependent, exercise-induced anaphylaxis. Clin Exp Allergy 2003;33:90-95

Wheat-dependent, exercise-induced anaphylaxis (WDEIA) is a severe allergy where wheat ingestion together with physical exercise induces anaphylaxis. We have previously shown that patients with WDEIA have IgE antibodies against gliadin proteins and identified -5 gliadin (Tri a 19) as a major allergen. ObjectiveThe aim of this study was to examine gliadin-specific IgG subclass, IgA and IgE antibodies, basophil histamine release and cell-mediated responses in WDEIA. MethodsSera and peripheral blood mononuclear cells (PBMC) were obtained from patients with WDEIA and from controls without wheat allergy. Serum antibodies to crude gliadin extract (CGE) and purified -5 gliadin were measured by ELISA and basophil reactivity by histamine-release test. Gliadin-induced cell-mediated responses were assessed by lymphocyte proliferation assay, and cytokine mRNA expression with real-time quantitative PCR. ResultsAll patients with WDEIA, but none of the controls, had IgE antibodies to CGE and -5 gliadin. Both allergens released high levels of histamine from the basophils of patients with WDEIA. Levels of IgA antibodies to CGE and -5 gliadin were significantly elevated in the patients, but the distribution of IgG subclass antibodies showed no statistically significant differences between the two groups. Proliferative responses of PBMC to CGE were increased in patients with WDEIA, and stimulation of PBMC with CGE caused, both in patients and in controls, a clear induction of IL-10 mRNA. Compared with the controls, induction of IL-10 mRNA expression in patients with WDEIA was significantly (P < 0.01) suppressed. ConclusionThese results suggest that, in addition to IgE antibodies against -5 gliadin, specific IgA antibodies may be involved in the pathogenesis of WDEIA. Decreased expression of IL-10 mRNA in PBMC during gliadin stimulation may facilitate the development of gliadin-specific T cell responses.

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[259] - Morita E, Matsuo H, Mihara S, Morimoto K, Savage AW, Tatham AS. Fast omega-gliadin is a major allergen in wheat-dependent exercise-induced anaphylaxis. J Dermatol Sci 2003;33:99-104

BACKGROUND: Wheat-dependent exercise-induced anaphylaxis is an anaphylaxy induced by physical exercise after ingestion of wheat. An immediate-type hypersensitivity to water/salt-insoluble fraction of wheat proteins (gluten) has been considered to underlie in this disease. OBJECTIVE: The aim of the study is to determine the major allergen in Japanese patients with wheat-dependent exercise-induced anaphylaxis by using a panel of purified wheat gliadins and glutenins. METHODS: Water/salt-insoluble wheat proteins, alpha-gliadin, beta-gliadin, gamma-gliadin, fast omega-gliadin, slow omega-gliadin, high molecular weight glutenin and low molecular weight glutenin, were purified, and five patients with wheat-dependent exercise-induced anaphylaxis, whose diagnose had been determined by positive-challenge test, were evaluated for skin prick test, dot-blotting test and CAP-RAST inhibition test by using these purified wheat proteins. RESULTS: The fast omega-gliadin was the most potent allergen among these water/salt-insoluble proteins when evaluated by skin prick test and dot-blotting test. Fast and slow omega-gliadin, and gamma-gliadin caused dose-dependent inhibition of the serum IgE-binding to solid-phase gluten in the patients. The incubation with fast omega-gliadin of the patient's serum caused dose-dependent inhibition in the IgE-binding to gamma-gliadin as well as slow omega-gliadin, indicating a cross-reactivity of these proteins in IgE-binding. CONCLUSION: We concluded that fast omega-gliadin is a major allergen among these water/salt-insoluble proteins for wheat-dependent exercise-induced anaphylaxis in Japanese patients, and IgE against fast omega-gliadin cross-reacts to gamma-gliadin and slow omega-gliadin.

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[260] - Battais F, Courcoux P, Popineau Y, Kanny G, Moneret-Vautrin DA, Denery-Papini S. Food allergy to wheat: differences in IgE binding proteins as a function of age and symptoms. J Cereal Sci 2005;42:109-117

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[261] - Jacquenet S, Morisset M, Battais F, Denery-Papini S, Croizier A, Beaudouin E, et al. Intérêt du CAP oméga-5 gliadine pour le diagnostic de l'allergie au blé induite par l'effort. Alim'Inter 2007;12:227

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[262] - Ledent C, Mairesse M. Urticaire par allergie alimentaire induite par l'exercice: intérêt du dosage des IgEs oméga 5 gliadine et isolats de blé. Rev Fr Allergol Immunol Clin 2008;48:272-273

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[263] - Le Corre Y, Drouet M, Nicolie B, Bonneau JC, Leclère JM, Beauvillain C. Anaphylaxie induite par l'exercice au blé (AIE-blé): rôle du Saccharomyces ? Rev Fr Allergol Immunol Clin 2008;48:274

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[264] - Daengsuwan T, Palosuo K, Phankingthongkum S, Visitsunthorn N, Jirapongsananuruk O, Alenius H, et al. IgE antibodies to omega-5 gliadin in children with wheat-induced anaphylaxis. Allergy 2005;60:506-509

Background: Wheat can cause severe immunoglobulin E (IgE)-mediated systemic reactions including anaphylaxis but knowledge on relevant wheat allergens at the molecular level is scanty. Methods: Seven children (aged from 6 months to 13 years) experiencing from 2 to 10 anaphylactic reactions in a year after eating food-containing wheat were examined. Purified omega-5 gliadin was used as an allergen in IgE enzyme-linked immunosorbent assay (ELISA) and in skin prick testing (SPT). Wheat CAP radioallergosorbent test (RAST) and SPT were also examined. Results: All seven anaphylactic children, but none of 15 control subjects had IgE antibodies to omega-5 gliadin in ELISA. Five of the six tested anaphylactic children showed positive SPT to omega-5 and crude gliadin, and all seven had positive wheat CAP RAST and SPT. One child was challenged with wheat, which caused anaphylaxis. After adherence to a wheat-free diet four children remained symptomless and three experienced one to two anaphylactic reactions. Conclusion: The present results show that wheat omega-5 gliadin is a major sensitizing allergen in children with wheat-induced anaphylaxis. They also suggest that omega-5 gliadin IgE ELISA could be used as a diagnostic test for this severe allergy.

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[265] - Beyer K, Schulz G, Wahn U, Niggemann B. Role of omega-5-gliadian-specific IgE antibodies in the diagnosis of wheat allergy in childhood. Allergy 2007;62(suppl. 83):104

Background: Wheat allergy is a common disease in early childhood. The diagnostic is currently based on oral food challenge tests. No good correlation between the outcome of oral food challenges and the level of wheat-specific serum IgE have been observed. However, it had been recently shown by others that wheat allergen omega-5-gliadin correlated well with oral challenge results. Over 80% of children with immediate symptoms to wheat had IgE antibodies to omega-5-gliadin, whereas none were detected in children with negative challenge tests. The aim of the present study was to confirm the role of omega-5-gliadin for the diagnosis of wheat allergy in our population. METHODS: Fifty-seven children, who underwent double-blind placebo controlled wheat challenge for diagnostics were included into the study. Age ranged from 6 month to 14 years (median age 1 year) and 95% had atopic dermatitis. Sera were obtained in all patients before challenge. omega-5- and wheat-specific IgE antibodies were measured in the sera using the Phadia® CAP system. Results: Out of 57 children, 27 had a positive wheat challenge with immediate reactions and 30 challenges were negative. No significant difference were observed regarding wheat-specific IgE antibodies in both patient groups (<0.35 to 96.3 kU/l, median 4.3 kU/l for allergic patients and <0.35 to 87.1 kU/l, median 1.05 for non-reactive children). omega-5-gliadin-specific IgE antibody concentrations did not differ significantly between both groups (0 to 16.3 kU/l, median 0.2 kU/l for allergic patients and 0 to 5.0 kU/l, median 0.07 for non-reactive children). Subanalysis of patients with wheat-specific IgE > 0.35 kU/l gave similar results. Importantly, 9 out of 30 non-allergic patients showed IgE antibodies to ?-5-gliadin. Conclusion: Levels of omega-5 gliadin-specific IgE antibodies did not correlate with the outcome of oral food challenges in patient with suspected wheat allergy. Therefore, measurement of omega-5 gliadin-specific IgE appears not to be helpful in the diagnostic of wheat allergy in our study population.

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[266] - Dahlström J, Halvorsen R, Matsuo H, Kohno K, Morita E. IgE antibodies to recombinant omega-5 gliadin in children with severe reactions to wheat. EAACI 25th Congress, Vienna, 10-14 June, 2006, Poster n°1504

Background Wheat is a staple food in the western world and thus it is of great importance to identify patients at risk of having severe allergic reactions to wheat. IgE sensitisation to wheat is common among food allergic patients, but does not always correlate with allergic symptoms. Oral food challenge is today the only way to identify patients with clinical symptoms to wheat. However, food challenges are often inconvenient and a potential risk for the patients. Therefore, more reliable in vitro tests are needed. Here we describe the use of three wheat allergen components to identify patients suffering from immediate severe reactions when ingesting wheat. Subjects Thirty children (9 month to 8 years old) with IgE antibodies (IgE ab) to wheat grain, gluten and gliadin, suspected of having allergic symptoms to wheat were referred to Voksentoppen, Oslo, for further clinical investigation and oral challenge. Fourteen of the children reacted when challenged with wheat whereas 16 were asymptomatic (but reacted to other foods than wheat). Forty healthy control subjects were included in the study. Methods Allergen specific and total IgE was measured with ImmunoCAPTM (Phadia AB, Uppsala, Sweden). The C-terminal part of omega-5 gliadin (rO5-glia) was expressed in E.coli by the pET system and purified using RP-HPLC and Pep A from O5-glia and Pep B from HMW glutenin, were synthesized. The rO5-glia, Pep A and Pep B were conjugated to individual ImmunoCAP. Results All 30 patients, both the 14 symptomatic and the 16 asymptomatic, had IgE ab to wheat grain, gluten and gliadin. Eleven of the 14 symptomatic children had conciderable levels of IgE ab to rO5-glia (1-35 kU/L), 10/14 to Pep A (0.48-16 kU/L) and 2/14 to Pep B . Among the children with severe general reactions to wheat 9/10 patients had IgE ab to rO5-glia and 9/10 to Pep A and only 2/10 to Pep B. Of the asymptomatic children only 3/16 had low levels of IgE ab to rO5-glia (0.48-1.8 kU/L) and 2/16 (0.38 - 0.63 kU/L) to Pep A and 1/16 to Pep B. None of the healthy controls had IgE ab to any of the tests. Conclusion Measurement of IgE ab to recombinant omega-5 gliadin and Peptide A are very good complements to the measurements of IgE ab to wheat grain, gluten and gliadin to identify children at risk of having severe immediate reactions after intake of wheat containing foods.

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[267] - Ito K, Takaoka Y, Futamura M, Sakamoto T, Kohno K, Morita E, et al. Omega-5-Gliadin Specific IgE as a Predictor of Wheat Allergy in Children. J Allergy Clin Immunol 2007;119(1 suppl):S191

RATIONALE: Wheat is the third-most common food allergen in Japanese children, but detection of wheat-specific IgE antibody is insufficient to diagnose wheat allergy because of low clinical specificity. Omega-5-gliadin is known to represent a major allergen in wheat-dependent exercise-induced anaphylaxis, but levels in immediate-type wheat allergy in children remain unclear. METHODS: IgE antibody to omega-5-gliadin was detected by ImmunmoCAP in sera from patients with wheat allergy (n=44; mean age, 3.4 years) diagnosed according to positive wheat challenge or apparent clinical history. Control patients (n=44; mean age, 4.9 years) with positive IgE for wheat (>=3.5 UA/ml) but without clinical symptoms after ingestion of wheat products were also recruited. RESULTS: Levels of wheat-specific IgE (mean ±SD) were 44.52 ±36.37 UA/ml in patients and 12.57 ±11.81 UA/ml in controls. Omega-5-gliadin-specific IgE was positive (>0.34 UA/ml) in 37 patients with wheat allergy (84.1%) and 12 controls(27.3%). Mean IgE titer in positive sera was 7.25 UA/ml in patients (range, 0.40-81.0 UA/ml) and 1.08 UA/ml in controls (0.35-4.80 UA/ml). Although only 1 control patient showed a level of 4.80 UA/ml (all others were <1.30 UA/ml), 100% positive predictive value was obtained using a cutoff of >5.0 UA/ml. Patients with high IgE titer to omega-5-gliadin tended to display severe reactions including respiratory symptoms or anaphylaxis. CONCLUSIONS: Detection of omega-5-gliadin-specific IgE is useful for the diagnosis of immediate-type wheat allergy in children comparing to that of wheat.

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[268] - Dahlström J, Ito K, Shibata R, Borres M, Matsuo H, Kohno K, et al. Omega-5 gliadin in the diagnosis of children with wheat allergy. Allergy 2007;62(suppl. 83):104

Background: Wheat is a staple food in the western world and thus it is of great importance to identify patients at risk of having severe allergic reactions to wheat. IgE sensitization to wheat is common among food allergic patients, but does not always correlate with allergic symptoms. Measurement of IgE to omega-5 gliadin has been reported useful in detecting patients with exercise induced symptoms to wheat. Moreover, children with immediate reactions are reported to have IgE to omega-5 gliadin. Here we report the usage of omega-5 gliadin to identify children suffering from immediate reactions when ingesting wheat. Subjects: There were 126 wheat sensitised children (1 to 15 years old) enrolled in the study. Among theese 71 children reacted when challenged with wheat or had a strong convincing clinical history of allergy to wheat and 55 children had no symptoms or had a negative challenge to ingested wheat. Methods: Allergen specific IgE antibodies were measured with ImmunoCAPTM (Phadia AB, Uppsala, Sweden). The C-terminal part of omega-5 gliadin (rO5-glia) was expressed in E.coli by the pET system, purified using RP-HPLC and conjugated to ImmunoCAP. Results: All 126 patients were sensitized to wheat, both the 71 children with symptoms and the 55 children having no symptoms when ingesting wheat. In the group of patients having clinical symptoms when ingesting wheat 61/71 (86%) had elevated levels of IgE to rO5-glia (0.40-81 kUA/L). Among the patients having no clinical symptoms when ingesting wheat, although sensitized to wheat, only 13/55 (23.6%) had IgE to rO5-glia (0.39-4.8 kUA/L). In this study the sensitivity was 86% and the specificity was 76% for the test. Conclusion: Measurement of IgE ab to omega-5 gliadin in wheat sensitized children is very useful to identify children at risk of developing immediate clinical symptoms after intake of wheat containing foods.

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[269] - Palosuo K, Varjonen E, Kekki OM, Klemola T, Kalkkinen N, Alenius H, et al. Wheat omega-5 gliadin is a major allergen in children with immediate allergy to ingested wheat. J Allergy Clin Immunol 2001;108:634-638

Sensitization to wheat by ingestion can lead to food allergy symptoms and wheat-dependent, exercise-induced anaphylaxis. Sensitization by inhalation causes bakers' asthma and rhinitis. Wheat allergens have been characterized at the molecular level in bakers' asthma and in wheat-dependent, exercise-induced anaphylaxis, in which omega-5 gliadin (Tri a 19) is a major allergen. However, little information is available regarding allergens responsible for hypersensitivity reactions to ingested wheat in children. OBJECTIVE: The aim of this study was to examine whether children with allergy to ingested wheat have IgE antibodies to omega-5 gliadin. METHODS: Sera were obtained from 40 children (mean age, 2.5 years; range, 0.7-8.2 years) with suspected wheat allergy who presented with atopic dermatitis and/or gastrointestinal and/or respiratory symptoms. Wheat allergy was diagnosed with open or double-blinded, placebo-controlled oral wheat challenge. Wheat omega-5 gliadin was purified by reversed-phase chromatography, and serum IgE antibodies to omega-5 gliadin were measured by means of ELISA. In vivo reactivity was studied by skin prick testing. Control sera were obtained from 22 children with no evidence of food allergies. RESULTS: In oral wheat challenge, 19 children (48%) reacted with immediate and 8 children (20%) with delayed hypersensitivity symptoms. Sixteen (84%) of the children with immediate symptoms had IgE antibodies to purified omega-5 gliadin in ELISA. In contrast, IgE antibodies to omega-5 gliadin were not detected in any of the children with delayed or negative challenge test results or in the control children. The diagnostic specificity and positive predictive value of omega-5 gliadin ELISA were each 100% for immediate challenge reactions. Skin prick testing with omega-5 gliadin was positive in 6 of 7 children with immediate challenge symptoms and negative in 2 children with delayed challenge symptoms. CONCLUSION: The results of this study show that omega-5 gliadin is a significant allergen in young children with immediate allergic reactions to ingested wheat. IgE testing with omega-5 gliadin could be used to reduce the need for oral wheat challenges in children.

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[270] - Shibata R, Nishima S, Kohno K, Morita E, Matsuo H, Tanaka A. Specific IgE Antibodies To omega-5 Gliadin-Indicator Of Wheat Anaphylaxis And Its Tolerance In Wheat Sensitized Children. J Allergy Clin Immunol 2007;119(1 suppl):S120

RATIONALE: Wheat is one of the common food allergens and sometimes induces anaphylaxis in infantile atopic dermatitis with high wheat-specific IgE. The diagnostic role of omega-5 gliadin specific IgE antibodies in patients with wheat-dependent excise-induced anaphylaxis has been demonstrated. OBJECTIVE: The aim of this study was to identify the specific IgE antibodies to omega -5 gliadin and synthetic combined epitope peptides A and B for children with wheat hypersensitivity and tolerance confirmed by challenge test. PATIENTS AND METHODS: Forty eight wheat allergy patients (mean age 3.2 years old) were enrolled. Wheat allergy was confirmed by wheat specific IgE and challenge test with wheat noodles. Specific IgE antibody to wheat, gluten, omega -5 gliadin, peptide A and B were measured by CAP-system. RESULTS: Patients with wheat anaphylaxis showed significantly higher levels (~37 UA/ml) of omega-5 gliadin specific IgE than those with local urticaria and atopic eczema. In contrast, 80% of challenge negative patients did not indicate omega -5 gliadin specific IgE. In follow up cases of 16 wheat hypersensitivity the omega -5 gliadin IgE antibodies were significantly decreased to undetectable levels after tolerance by confirmed challenge, although wheat and gluten IgE antibodies were persistent at the positive levels. Specific IgE antibodies to peptide A were also detected at low levels in patients with wheat anaphylaxis but peptide B IgE were did not identified. CONCLUSIONS: Measurement of IgE levels specific to omega -5 gliadin is useful as a prediction of wheat-induced anaphylaxis and its tolerance.

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[271] - Palosuo K, Alenius H, Varjonen E, Koivuluhta M, Mikkola JH, Keskinen H, et al. A novel wheat gliadin as a cause of exercise-induced anaphylaxis. J Allergy Clin Immunol 1999;103:912-917

BACKGROUND: Food-dependent, exercise-induced anaphylaxis is a severe form of allergy; the reaction is caused by ingestion of a specific food before exercise. This disorder often escapes diagnosis because neither the ingested food nor the exercise alone induces the symptoms. OBJECTIVE: The aim of the study was to characterize the allergens involved in wheat-dependent, exercise-induced anaphylaxis and to describe the clinical outcome in a series of 18 adult patients. METHODS: All 18 patients had experienced recurrent episodes of generalized urticaria during exercise, 17 patients in association with collapse and 15 patients with an anaphylactic reaction. The symptoms appeared only when the patients had eaten food containing wheat before exercise. Wheat allergens were detected by immunoblotting, purified by gel filtration and reversed-phase chromatography, and subjected to N-terminal sequencing. The IgE-binding ability of the purified proteins was studied by ELISA, and their in vivo reactivity was studied by skin prick testing. RESULTS: IgE antibodies from pooled patient sera were bound to 65-kd and 40-kd wheat proteins in immunoblotting. The 65-kd allergen was a previously undescribed wheat protein, showing 61% sequence identity to gamma-gliadin, whereas the 40-kd allergen had 100% identity to alpha-gliadin. In ELISA, all 18 patients showed elevated IgE levels to the novel gamma-like gliadin, and 13 of the patients showed elevated IgE levels to the alpha-gliadin. None of the 54 control subjects with wheat allergy, urticaria, or coeliac disease had IgE antibodies to the gamma-like gliadin. The in vivo reactivity of the gamma-like gliadin was verified by positive skin prick test responses in all of the 15 patients who were tested. During the follow-up on a gluten-free or wheat-free diet, 3 patients experienced reactions after having unknowingly eaten wheat before exercise, but all the other patients who were adhering to the diet remained symptom-free. CONCLUSION: This study shows that wheat is a frequent cause of food-dependent, exercise-induced anaphylaxis and suggests that the major allergen is a previously undescribed gamma-like gliadin. For screening of this life-threatening allergy, we recommend skin prick testing with crude gliadin and we recommend a gluten-free diet for treatment.

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[272] - Bouchez-Mahiout I, Snégaroff J, Boulenc E, Pecquet C, Choudat D, Raison-Peyron N, et al. Spécificité des protéines impliquées dans différentes formes d’allergie au blé. Rev Fr Allergol Immunol Clin 2007;47:285

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Les allergènes du blé

Allergie respiratoire aux farines de céréales

Allergie aux isolats / hydrolysats de gluten

Anaphylaxie au blé induite par l’effort

Diagnostic des réactions au blé

Rubriques

Dans la même rubrique

Les céréales : généralités et réactions croisées