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Le lupin

mardi 29 avril 2008, par Allerdata


Le lupin a de nombreux atouts pour en faire un ingrédient de plus en plus utilisé en technologie alimentaire :

  • il est riche en protéines,
  • il est sans gluten,
  • on peut en faire des concentrés (>60% de protéines),
  • c’est un bon émulsifiant,
  • ses acides aminés peuvent complémenter ceux des céréales,
  • il est de culture aisée, ..

Parmi les espèces de lupin on distingue :

  • le lupin blanc (Lupinus albus),
  • le lupin bleu (L. angustifolius) et
  • le lupin jaune (L. luteus).
  • C’est surtout le lupin blanc qui a été étudié.

On trouve du lupin dans de très nombreux produits :

  • en boulangerie (autorisé jusqu’à 10% dans la farine),
  • dans des produits céréaliers,
  • en biscuiterie,
  • dans des pâtes alimentaires ,
  • des soupes,
  • des bouillons, etc..

Ses graines sont parfois consommées bouillies et séchées.

En Allemagne, on fabrique une sorte de tofu avec le lupin (Lopino®).


Le lupin est, comme le soja, le type-même de l’ « allergène » caché . Il n’est pas toujours facile, d’ailleurs, de pointer le lupin comme responsable d’une réaction alimentaire car il peut se trouver associé dans l’aliment avec des protéines (ou des lécithines) de soja .


Les premiers cas d’allergie au lupin concernaient des pâtes alimentaires (S. Hefle, en 1994 ).

Depuis, de très nombreux travaux ont montré un potentiel allergénique important pour les protéines de lupin et ont amené à ajouter le lupin à la liste des aliments/ingrédients à étiquetage obligatoire.

L’allergie au lupin est classiquement évoquée dans le cadre d’une allergie à l’arachide (cf. Réactivité croisée entre Fabacées). Mais il existe de nombreux cas d’allergie isolée au lupin .

Il faut, de plus, envisager le rôle d’une pollinose au bouleau, de sorte qu’une réactivité au lupin et à l’arachide peut résulter d’une même sensibilisation à des protéines PR-10 . (cf. Fabacées et bouleau).

La farine de lupin est aussi responsable d’allergie respiratoire professionnelle. Parfois cette dernière est doublée d’une allergie alimentaire pour le lupin .


Une modification de certaines protéines pourrait survenir lors de la préparation des isolats de lupin .

Les allergènes du lupin

Une certaine confusion subsiste au sein des protéines IgE-réactives du lupin. Cela est du, entre autres, à l’usage de dénominations anciennes ou imprécises comme « 7S », « globulines », « conglutines », etc..

Ces appellations basées sur des propriétés physicochimiques masquent des différences existant sur le plan moléculaire (familles protéines différentes) et sur le plan immunologique.

A cela s’ajoute la grande hétérogénéité des complexes moléculaires adoptés par la plupart des protéines de stockage des graines.

Les techniques séparatives bidimensionnelles sont donc à préférer pour mieux identifier les protéines IgE-réactives .

Mais ce gain de précision conduit à de nouveaux problèmes, comme celui de distinguer ou non des protéines quasiment identiques : ainsi, on a longtemps trouvé dans la base Allergome 2 protéines distinctes, une « viciline » et une « béta conglutine », alors que ces 2 protéines de 62kD sont identiques à 94% .

Les travaux d’identification des allergènes ont essentiellement concerné le lupin blanc (Lupinus albus) .

On distingue :

  • des alpha conglutines : ces protéines s’apparentent aux légumines, sédimentent en 11-12S et se trouvent à l’état naturel sous forme d’hexamères. Chaque sous-unité est elle-même composée d’une chaîne acide (45-54 kD) et d’une chaîne basique (20 kD). La chaîne acide serait glycosylée .
  • des béta conglutines : ces protéines de type viciline sédimentent en 7S, forment des trimères dont les sous-unités présentent une grande diversité (20 à 80 kD). Les protéines repérées par Peeters ont une certaine homologie avec d’autres vicilines de Fabacées : environ 52% d’identité avec la béta conglycinine de soja et 47% avec Ara h 1 (arachide)
  • une gamma conglutine qui, elle aussi, sédimente en 7S mais qui se range dans un type particulier de protéines de stockage, à l’instar de la « basic 7S globulin » trouvée dans le soja. Elle pourrait être l’homologue de la gamma conglutine de l’amande (45 kD, 7S) qui présente également une activité de type lectine.
    La gamma conglutine de lupin est glycosylée, forme un tétramère à l’état naturel, chaque sous-unité étant composée de 2 chaînes reliées par un pont disulfure (14 et 30 kD)
  • une delta conglutine a aussi été décrite, protéine 2S, monomérique, ayant 2 chaînes couplées par un pont SS (4 et 9 kD).

Les blots 2D montrent un grand nombre de spots IgE-réactifs, très variables d’un patient à un autre, montrant que la liste des protéines potentiellement allergéniques dans le lupin est encore très incomplète.

Une profiline a été identifiée .

Une PR-10, Bet v 1-like, est probable, comme dans d’autres Fabacées.

L’importance de telle ou telle fraction au sein de l’IgE-réactivité globale du lupin est très mal connue.

Il semble que les protéines de stockage aient une place prépondérante. Moneret-Vautrin avait montré, par exemple, que 7 sujets/7 étaient positifs pour une fraction de 43 kD .

La profiline était IgE-réactive chez la moitié des patients dans la seule étude concernant cet allergène .

La conglutine gamma était, par contre, négative dans une étude portant sur 5 patients .

On le voit, les données sont très limitées.

La relevance clinique de ces positivités in vitro est difficile à apprécier, d’autant plus quand le lupin s’inscrit dans un contexte de réactivité croisée (cf. Bouleau et Fabacées, Réactivité croisée entre Fabacées).

Enfin, une protéine de 55 kDa dite « conglutine », issue des graines du lupin bleu (L. angustifolius) a été inscrite dans la liste IUIS sous le nom de Lup an 1. Mais rien n’est connu de cette protéine, pas même la prévalence de sa positivité, car cet « allergène » a été soumis directement au comité IUIS sans publication dans la littérature …

Diagnostic

En France, les tests cutanés et les tests in vitro sont basés sur des extraits de lupin blanc (L. albus).

Fort heureusement, c’est aussi le lupin qui est majoritairement utilisé dans les aliments manufacturés réalisés en France.

Mais en Allemagne et en Europe centrale le lupin jaune (L. luteus) est largement cultivé.

Quant au lupin bleu (L. angustifolius) il représente la plus grande part de la production mondiale de lupin, toutes espèces confondues. Si l’Australie est, pour le moment, le producteur principal de lupin bleu, ce dernier peut être importé et cultivé en France.

Rien ne dit que les tests diagnostiques à base de lupin blanc sont tout à fait adaptés à d’autres lupins.

On possède très peu de données sur l’efficacité des TC ou des tests in vitro dans le cas du lupin. Et encore moins sur la possible distorsion entre ces tests basés sur des extraits réalisés avec des graines crues alors que les patients entrent en contact (alimentaire) uniquement avec des produits cuits.

Les rares données de la littérature sont plutôt négatives et soulignent les difficultés d’un diagnostic positif si l’on ne peut avoir recours à un TPO :

  • aucune relation entre le résultat du TC ou du CAP et le résultat du TPODA
  • la prédiction d’un TPO positif pour un TC de 6mm ou plus n’est pas possible, le likehood ratio n’étant que de 1,1 (NB : le likehood ratio est plus adapté que la VPP et devient significatif quand il est supérieur à 10).
  • En revanche, on pourrait se servir d’un TC inférieur à 3 mm pour écarter une allergie car le likehood ratio est alors de 15


Bien que cela n’ait pas été vérifié jusqu’à présent, le lupin doit très certainement présenter une réactivité de type CCD comme le font nombre d’autres Fabacées.

Stabilité à la chaleur et à la digestion

Peu de données sont disponibles.

L’IgE-réactivité résiste bien à l’ébullition et il faut atteindre des températures très élevées (>130°C) pour voir une baisse sensible d’IgE-réactivité .

La digestion des protéines de lupin n’a pratiquement pas été étudiée sur le plan allergologique. La gamma conglutine serait facilement décomposée en digestion pancréatique .

Réactivités croisées du lupin

Les relations lupin-arachide et lupin-autres Fabacées sont décrites ailleurs (cf. Réactivité croisée entre Fabacées).

[1] - Rojas-Hijazo B, Garcés MM, Caballero ML, Alloza P, Moneo I. Unsuspected Lupin Allergens Hidden in Food. Int Arch Allergy Immunol 2006;141:47-50
BACKGROUND: Lupin is a herbaceous plant from the legume family whose seed allergens usually have cross-reaction with peanut. Lupin flour is used in human nutrition because of its high nutritional and functional qualities. AIMS: The aim of this work was to detect non-specified lupin proteins contained in several manufactured foods . METHODS: Serum from a patient suffering anaphylactic episodes after ingestion of a certain brand of cookies and with oral allergy syndrome after eating chicken bouillon was used as a tracer. Lupin seeds and commercial food extracts were analyzed by SDS-PAGE, immunoblotting and immunoblotting inhibition. Lupin extract allergenicity after thermal processing was also analyzed . RESULTS: A lupin allergen with a molecular weight close to 14 kDa was detected in extracts from cookies, a chicken bouillon cube and a chicken dehydrated soup . CONCLUSIONS: The presence of unsuspected, hidden non-specified lupin sources in food labeling was demonstrated. According to the results of this study, it is important for food-allergic patients that food labels should declare all the components irrespective of their quantity.
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[2] - Fæste CK, Løvik M, Wiker HG, Egaas E. A Case of Peanut Cross-Allergy to Lupine Flour in a Hot Dog Bread. Int Arch Allergy Immunol 2004;135:36-39
BACKGROUND: In a case monitored by the Norwegian National Register for Severe Allergic Reactions to Food, a patient with peanut allergy experienced an allergic reaction after eating a particular brand of hot dog bread. The aim of this study was to identify the eliciting allergen . METHODS: Extracts from the hot dog bread and reference material from peanut, lupine and lupine-fortified food products were analysed by immunochemical methods with patient serum and a new polyclonal anti-lupine antibody . RESULTS: Evidence could be provided that the hot dog bread contained proteins from lupine but not from peanut . CONCLUSION: Crossed peanut-lupine allergy can have clinical significance. A peanut-allergic patient reacted against hidden lupine protein in a hot dog bread. Presented with our results, the producer confirmed the use of lupine flour and changed the ingredient list
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[3] - Hefle SL, Lemanske RF Jr, Bush RK. Adverse reaction to lupine-fortified pasta. J Allergy Clin Immunol 1994;94:167-172
A 5-year-old girl with peanut sensitivity experienced urticaria and angioedema after ingesting a spaghetti-like pasta fortified with sweet lupine seed flour. The pasta was extracted and used in immunologic studies in patients with peanut sensitivity to determine whether such individuals are at similar risk. Results of skin prick tests with the lupine pasta extract were positive in five of seven subjects; these patients also reported a history of adverse reactions to green peas. In direct RAST studies IgE binding from pooled sera from patients with peanut sensitivity to the lupine pasta extract was 7 times that of a nonallergic control serum, and individual serum samples demonstrated binding from 1 to 6 times that of the negative control. Direct RAST studies of lupine seed flour with serum samples from patients with peanut allergy demonstrated IgE binding 1 to 11 times that of the negative control. Immunoblotting studies of electrophoretically separated pasta extract and lupine seed flour proteins showed IgE-binding protein bands at approximately 21 kd and in the range of 35 to 55 kd molecular weight. We conclude that some peanut-sensitive patients may be at risk for adverse reactions to lupine.
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[4] - Quaresma RR, Viseu R, Martins LM, Tomaz E, Inacio F. Allergic primary sensitization to lupine seed. Allergy 2007;62:1473-1474
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[5] - Wüthrich B. Anaphylactic reaction to lupine flour because of a primary sensitization. Allergy 2008;63:476-477
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[6] - Peeters KABM, Nordlee JA, Penninks AH, Chen L, Goodman RE, Bruijnzeel-Koomen CAFM, et al. Lupine allergy: Not simply cross-reactivity with peanut or soy. J Allergy Clin Immunol 2007;120:647-653
BACKGROUND: Reports of lupine allergy are increasing as its use in food products increases. Lupine allergy might be the consequence of cross-reactivity after sensitization to peanut or other legumes or de novo sensitization. Lupine allergens have not been completely characterized . OBJECTIVES: We sought to identify allergens associated with lupine allergy, evaluate potential cross-reactivity with peanut, and determine eliciting doses (EDs) for lupine allergy by using double-blind, placebo-controlled food challenges . METHODS: Six patients with a history of allergic reactions to lupine flour were evaluated by using skin prick tests, CAP tests, and double-blind, placebo-controlled food challenges. Three of these patients were also allergic to peanut. Lupine allergens were characterized by means of IgE immunoblotting and peptide sequencing . RESULTS: In all 6 patients the ED for lupine flour was 3 mg or less for subjective symptoms and 300 mg or more for objective symptoms. The low ED and moderate-to-severe historical symptoms indicate significant allergenicity of lupine flour. Two patients allergic to lupine but not to peanut displayed IgE binding predominantly to approximately 66-kd proteins and weak binding to 14- and 24-kd proteins, whereas patients with peanut allergy and lupine allergy showed weak binding to lupine proteins of about 14 to 21 or 66 kd. Inhibition of binding was primarily species specific . CONCLUSION: Lupine allergy can occur either separately or together with peanut allergy, as demonstrated by 3 patients who are cosensitized to peanut and lupine. CLINICAL IMPLICATIONS: Lupine flour is allergenic and potentially cross-reactive with peanut allergen, thus posing some risk if used as a replacement for soy flour.
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[7] - Crespo JF, Rodríguez J, Vives R, James JM, Reaño M, Daroca P, et al. Occupational IgE-mediated allergy after exposure to lupine seed flour. J Allergy Clin Immunol 2001;108:295-297
The ingestion of lupine seed flour (LSF) has been reported as a cause of allergic reactions, particularly in patients sensitized to peanut, but there is little evidence of its allergenic potential after inhalation. We sought to evaluate the clinical and immunologic reactivity to lupine in employees working with this seed flour. An occupational history was obtained in 7 subjects (median age, 35 years) working with LSF at an agricultural research center. Three subjects (1, 6, and 7) reported work-related allergy symptoms immediately after being exposed to lupine. Skin prick test results with LSF extract were positive in these 3 patients with work-related symptoms. Moreover, lupine-specific IgE antibodies were detected in subjects 6 and 7. In subject 6, the controlled exposure to LSF elicited immediate naso-ocular symptoms without changes in FEV(1). In subject 7, a bronchial provocation with LSF extract elicited an immediate fall (25%) in FEV(1). Double-blinded, placebo-controlled LSF oral challenge results were positive in subjects 6 and 7. Immunologic reactivity to other legumes was detected in subjects 6 and 7, but specific inhalation testing and oral challenge results were negative. Thus, the inhalation of lupine flour could be an important cause of allergic sensitization in exposed workers and might give rise to occupational asthma and food allergy.
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[8] - Wait R, Gianazza E, Brambilla D, Eberini I, Morandi S, Arnoldi A, et al. Analysis of Lupinus albus storage proteins by two-dimensional electrophoresis and mass spectrometry. J Agric Food Chem 2005;53:4599-4606
A laboratory-prepared total protein extract (TPE) and a lupin protein isolate (LPI-E) produced in a pilot plant were submitted to a detailed two-dimensional (2DE) proteomic investigation. Recent findings have indicated that in an established rodent model of hyperlipidemia, moderate daily intakes of LPI-Es lead to a reduction of total and low-density lipoprotein cholesterol levels, and the knowledge of the actual composition of the protein sample used in that study is at the basis of further structure/action investigations. The experimental results indicate that the semi-industrial procedure used for the production of LPI-E damages only marginally the proteins. It does, however, cleave some disulfide bridges and induce mild proteolysis, as confirmed by the higher number of resolved protein spots in the low Mr and acidic pI region of the 2DE map. Out of 72 spots submitted to mass spectrometry and compared with available protein databases, 42 correspond to fragments of beta-conglutin, the 7S globulin of lupin, spanning between positions 37 and 495 of the protein sequence. Using the bioinformatic tool BlastP, these peptides were compared to the alpha'-subunit of beta-conglycinin, the 7S globulin of soybean, this being the most active hypocholesterolemic component of soybean protein, as shown by in vitro and in vivo experiments. At least 18 peptides derived from beta-conglutin, having a percentage identity higher than 50% and a similarity percentage higher than 70% vs the alpha'-subunit of beta-conglycinin, are likely candidates to be the biologically active components of lupin protein.
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[9] - Peeters KABM, Nordlee JA, Penninks AH, Chen L, Goodman RE, Bruijnzeel-Koomen CAFM, et al. Lupine allergy: Not simply cross-reactivity with peanut or soy. J Allergy Clin Immunol 2007;120:647-653
BACKGROUND: Reports of lupine allergy are increasing as its use in food products increases. Lupine allergy might be the consequence of cross-reactivity after sensitization to peanut or other legumes or de novo sensitization. Lupine allergens have not been completely characterized . OBJECTIVES: We sought to identify allergens associated with lupine allergy, evaluate potential cross-reactivity with peanut, and determine eliciting doses (EDs) for lupine allergy by using double-blind, placebo-controlled food challenges . METHODS: Six patients with a history of allergic reactions to lupine flour were evaluated by using skin prick tests, CAP tests, and double-blind, placebo-controlled food challenges. Three of these patients were also allergic to peanut. Lupine allergens were characterized by means of IgE immunoblotting and peptide sequencing . RESULTS: In all 6 patients the ED for lupine flour was 3 mg or less for subjective symptoms and 300 mg or more for objective symptoms. The low ED and moderate-to-severe historical symptoms indicate significant allergenicity of lupine flour. Two patients allergic to lupine but not to peanut displayed IgE binding predominantly to approximately 66-kd proteins and weak binding to 14- and 24-kd proteins, whereas patients with peanut allergy and lupine allergy showed weak binding to lupine proteins of about 14 to 21 or 66 kd. Inhibition of binding was primarily species specific . CONCLUSION: Lupine allergy can occur either separately or together with peanut allergy, as demonstrated by 3 patients who are cosensitized to peanut and lupine. CLINICAL IMPLICATIONS: Lupine flour is allergenic and potentially cross-reactive with peanut allergen, thus posing some risk if used as a replacement for soy flour.
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[10] - Peeters KABM, Nordlee JA, Penninks AH, Chen L, Goodman RE, Bruijnzeel-Koomen CAFM, et al. Lupine allergy: Not simply cross-reactivity with peanut or soy. J Allergy Clin Immunol 2007;120:647-653
BACKGROUND: Reports of lupine allergy are increasing as its use in food products increases. Lupine allergy might be the consequence of cross-reactivity after sensitization to peanut or other legumes or de novo sensitization. Lupine allergens have not been completely characterized . OBJECTIVES: We sought to identify allergens associated with lupine allergy, evaluate potential cross-reactivity with peanut, and determine eliciting doses (EDs) for lupine allergy by using double-blind, placebo-controlled food challenges . METHODS: Six patients with a history of allergic reactions to lupine flour were evaluated by using skin prick tests, CAP tests, and double-blind, placebo-controlled food challenges. Three of these patients were also allergic to peanut. Lupine allergens were characterized by means of IgE immunoblotting and peptide sequencing . RESULTS: In all 6 patients the ED for lupine flour was 3 mg or less for subjective symptoms and 300 mg or more for objective symptoms. The low ED and moderate-to-severe historical symptoms indicate significant allergenicity of lupine flour. Two patients allergic to lupine but not to peanut displayed IgE binding predominantly to approximately 66-kd proteins and weak binding to 14- and 24-kd proteins, whereas patients with peanut allergy and lupine allergy showed weak binding to lupine proteins of about 14 to 21 or 66 kd. Inhibition of binding was primarily species specific . CONCLUSION: Lupine allergy can occur either separately or together with peanut allergy, as demonstrated by 3 patients who are cosensitized to peanut and lupine. CLINICAL IMPLICATIONS: Lupine flour is allergenic and potentially cross-reactive with peanut allergen, thus posing some risk if used as a replacement for soy flour.
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[11] - Peeters KABM, Nordlee JA, Penninks AH, Chen L, Goodman RE, Bruijnzeel-Koomen CAFM, et al. Lupine allergy: Not simply cross-reactivity with peanut or soy. J Allergy Clin Immunol 2007;120:647-653
BACKGROUND: Reports of lupine allergy are increasing as its use in food products increases. Lupine allergy might be the consequence of cross-reactivity after sensitization to peanut or other legumes or de novo sensitization. Lupine allergens have not been completely characterized . OBJECTIVES: We sought to identify allergens associated with lupine allergy, evaluate potential cross-reactivity with peanut, and determine eliciting doses (EDs) for lupine allergy by using double-blind, placebo-controlled food challenges . METHODS: Six patients with a history of allergic reactions to lupine flour were evaluated by using skin prick tests, CAP tests, and double-blind, placebo-controlled food challenges. Three of these patients were also allergic to peanut. Lupine allergens were characterized by means of IgE immunoblotting and peptide sequencing . RESULTS: In all 6 patients the ED for lupine flour was 3 mg or less for subjective symptoms and 300 mg or more for objective symptoms. The low ED and moderate-to-severe historical symptoms indicate significant allergenicity of lupine flour. Two patients allergic to lupine but not to peanut displayed IgE binding predominantly to approximately 66-kd proteins and weak binding to 14- and 24-kd proteins, whereas patients with peanut allergy and lupine allergy showed weak binding to lupine proteins of about 14 to 21 or 66 kd. Inhibition of binding was primarily species specific . CONCLUSION: Lupine allergy can occur either separately or together with peanut allergy, as demonstrated by 3 patients who are cosensitized to peanut and lupine. CLINICAL IMPLICATIONS: Lupine flour is allergenic and potentially cross-reactive with peanut allergen, thus posing some risk if used as a replacement for soy flour.
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[12] - Magni C, Herndl A, Sironi E, Scarafoni A, Ballabio C, Restani P, et al. One- and Two-Dimensional Electrophoretic Identification of IgE-Binding Polypeptides of Lupinus albus and Other Legume Seeds. J Agric Food Chem 2005;53:4567-4571
The prevalence of food allergies in the world population requires integrated approaches to identify new potential allergens, especially those of plant origin. The aim of this work was the allergen in vitro analysis of Lupinus albus seed proteome, a promising food protein source, and the assessment of IgE cross-reactivities with other more diffused legume species. A combination of one- and two-dimensional gel electrophoresis and immunoblotting analyses with specific IgGs for band identification and lupin-sensitized patients' circulating IgEs for allergenicity studies has been used. Two lupin proteins, namely, conglutin gamma and 11S globulin basic subunits, strongly reacted with all patients' sera. Also, cross-reactivities with the homologous polypeptides of other legume species were observed. Otherwise, no reaction at all was detected with a 2S-type lupin protein. This global electrophoretic approach has allowed the identification of a new potential lupin allergen and confirmed the cross-reactivity among the legume 11S globulin basic subunits.
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[13] - Dooper MMBW, Holden L, Fæste CK, Thompson KM, Egaas E. Monoclonal Antibodies against the Candidate Lupin Allergens alpha-Conglutin and beta-Conglutin. Int Arch Allergy Immunol 2007;143:49-58
BACKGROUND: The ingestion of dietary products containing sweet lupin (such as Lupinus albus or Lupinus angustifolius) has been reported to cause IgE-mediated allergic reactions. Recent studies have indicated lupin globulins as important IgE binding proteins. The aim of the present study was to generate and characterize monoclonal antibodies (mAbs) against lupin seed proteins . METHODS: Mice were immunized with a protein isolate from L. albus and mAbs were obtained by hybridoma techniques. Albumins and globulins were extracted, and the globulin fraction was separated further into conglutins by anion exchange chromatography. Specificities, binding patterns and applications of the mAbs were investigated by immunochemical methods . RESULTS: Five mAbs were produced: Lu11 (an IgG2b antibody), Lu8, Lu18, Lu34 and Lu35 (all IgM antibodies). The mAbs reacted strongly with protein isolates from both L. albus and L. angustifolius. All mAbs are directed towards the lupin globulin fraction; Lu11 and Lu18 recognize alpha-conglutin, while Lu8, Lu34 and Lu35 recognize beta-conglutin. In addition, Lu11 inhibited the binding of IgE from patients with positive skin prick tests to lupin proteins in a competitive ELISA by approximately 30%. Furthermore, preliminary results show that Lu11 can be used to develop a sensitive method for the detection of alpha-conglutin in foods . CONCLUSIONS: Lupin globulins are immunogenic and alpha-conglutin is a potential allergen. This is the first study describing mAbs against the candidate lupin allergens, emphasizing the importance of additional studies on conglutins in lupin allergy
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[14] - Giner M, Monteseirin J, Bonilla I, Camacho MJ, Garcia C, Martinez A, et al. Purification and characterization of profilin from Lupinus albus. EAACI 19th Congress, Lisbon, 1-5 July, 2000, Poster
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[15] - Moneret-Vautrin DA, Guérin L, Kanny G, Flabbee J, Frémont S, Morisset M. Cross-allergenicity of peanut and lupine: the risk of lupine allergy in patients allergic to peanuts. J Allergy Clin Immunol 1999;104:883-888
BACKGROUND: Peanut allergy is common, but cross-allergy between legumes is rare. Proteins from Lupinus albus are increasingly eaten in the form of seeds or additives to wheat flour. The risk of cross-allergenicity is still insufficiently known . OBJECTIVE: We sought to study the risk of cross-allergy to lupine in patients allergic to peanut and to study lupine allergenicity . METHODS: Twenty-four patients allergic to peanuts were studied by means of skin prick tests with native lupine flour from Lupinus albus. Double-blind oral challenge tests were performed with lupine flour and peanut in 8 of these patients. Specific IgEs were assayed for peanut, lupine flour, and pollen in 6 sera. RAST inhibition tests for lupine pollen by peanut were performed on 4 of these sera. Peanut and lupine flour immunoblots were carried out for 6 sera, and crossed immunoblot inhibitions for peanut by lupine flour and lupine flour by peanut were carried out for 2 sera . RESULTS: The skin prick test responses with lupine flour were positive in 11 (44%) subjects. The challenge test responses were positive in 7 of 8 subjects at the same doses as with peanut. The major lupine flour allergen (molecular mass, 43 kd) is present in peanuts. The RAST inhibition and immunoblot tests indicated cross-reactivity of peanut with the lupine flour and pollen . CONCLUSIONS: The risk of crossed peanut-lupine allergy is high, contrary to the risk with other legumes. The inclusion of 10% lupine flour in wheat flour without mandatory labeling makes lupine a hidden allergen, presenting a major risk of cross-reaction in subjects already allergic to peanut products. A high sensitizing potential can also be postulated for this legume.
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[16] - Mills ENC, Jenkins J, Marigheto N, Belton PS, Gunning AP, Morris VJ. Allergens of the cupin superfamily. Biochem Soc Trans 2002;30:925-929
The cupin family comprises a family of proteins possessing a common beta-barrel structure that is thought to have originated in a prokaryotic ancestor. This structural motif is found as a single domain in fungal spherulins, fern sporulins and the germins/oxalate oxidase proteins of plants, while the globular storage proteins of plants, called legumins (11 S) and euvicilins (7 S), are two-domain cupins. The 11 S globulins are hexameric heteroligomeric proteins of Mr ~ 360000, with each subunit comprising an acidic 30000ˆ40000-Mr polypeptide that is disulphide-linked to a 20000-Mr basic polypeptide. A number of cupins have been identified as major plant food allergens, including the 7 S globulins of soybean (beta-conglycinin), peanut (conarachin; Ara h 1), walnut (Jug r 2) and lentil, and the 11 S globulins of peanut (arachin; Ara h 3), soybean (glycinin) and possibly also coconut and walnut. Other members of the cupin superfamily have not been identified as allergens, with the exception of one germin (germination-specific protein) from pepper. Cupins are generally very stable proteins. A summary of our current knowledge of allergenic seed storage globulins will be presented, together with an overview of cupin structure and stability properties, as illustrated by the allergenic soya globulins, glycinin and beta-conglycinin.
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[17] - Peeters KABM, Nordlee JA, Penninks AH, Chen L, Goodman RE, Bruijnzeel-Koomen CAFM, et al. Lupine allergy: Not simply cross-reactivity with peanut or soy. J Allergy Clin Immunol 2007;120:647-653
BACKGROUND: Reports of lupine allergy are increasing as its use in food products increases. Lupine allergy might be the consequence of cross-reactivity after sensitization to peanut or other legumes or de novo sensitization. Lupine allergens have not been completely characterized . OBJECTIVES: We sought to identify allergens associated with lupine allergy, evaluate potential cross-reactivity with peanut, and determine eliciting doses (EDs) for lupine allergy by using double-blind, placebo-controlled food challenges . METHODS: Six patients with a history of allergic reactions to lupine flour were evaluated by using skin prick tests, CAP tests, and double-blind, placebo-controlled food challenges. Three of these patients were also allergic to peanut. Lupine allergens were characterized by means of IgE immunoblotting and peptide sequencing . RESULTS: In all 6 patients the ED for lupine flour was 3 mg or less for subjective symptoms and 300 mg or more for objective symptoms. The low ED and moderate-to-severe historical symptoms indicate significant allergenicity of lupine flour. Two patients allergic to lupine but not to peanut displayed IgE binding predominantly to approximately 66-kd proteins and weak binding to 14- and 24-kd proteins, whereas patients with peanut allergy and lupine allergy showed weak binding to lupine proteins of about 14 to 21 or 66 kd. Inhibition of binding was primarily species specific . CONCLUSION: Lupine allergy can occur either separately or together with peanut allergy, as demonstrated by 3 patients who are cosensitized to peanut and lupine. CLINICAL IMPLICATIONS: Lupine flour is allergenic and potentially cross-reactive with peanut allergen, thus posing some risk if used as a replacement for soy flour.
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[18] - Giner M, Monteseirin J, Bonilla I, Camacho MJ, Garcia C, Martinez A, et al. Purification and characterization of profilin from Lupinus albus. EAACI 19th Congress, Lisbon, 1-5 July, 2000, Poster
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[19] - Moneret-Vautrin DA, Guérin L, Kanny G, Flabbee J, Frémont S, Morisset M. Cross-allergenicity of peanut and lupine: the risk of lupine allergy in patients allergic to peanuts. J Allergy Clin Immunol 1999;104:883-888
BACKGROUND: Peanut allergy is common, but cross-allergy between legumes is rare. Proteins from Lupinus albus are increasingly eaten in the form of seeds or additives to wheat flour. The risk of cross-allergenicity is still insufficiently known . OBJECTIVE: We sought to study the risk of cross-allergy to lupine in patients allergic to peanut and to study lupine allergenicity . METHODS: Twenty-four patients allergic to peanuts were studied by means of skin prick tests with native lupine flour from Lupinus albus. Double-blind oral challenge tests were performed with lupine flour and peanut in 8 of these patients. Specific IgEs were assayed for peanut, lupine flour, and pollen in 6 sera. RAST inhibition tests for lupine pollen by peanut were performed on 4 of these sera. Peanut and lupine flour immunoblots were carried out for 6 sera, and crossed immunoblot inhibitions for peanut by lupine flour and lupine flour by peanut were carried out for 2 sera . RESULTS: The skin prick test responses with lupine flour were positive in 11 (44%) subjects. The challenge test responses were positive in 7 of 8 subjects at the same doses as with peanut. The major lupine flour allergen (molecular mass, 43 kd) is present in peanuts. The RAST inhibition and immunoblot tests indicated cross-reactivity of peanut with the lupine flour and pollen . CONCLUSIONS: The risk of crossed peanut-lupine allergy is high, contrary to the risk with other legumes. The inclusion of 10% lupine flour in wheat flour without mandatory labeling makes lupine a hidden allergen, presenting a major risk of cross-reaction in subjects already allergic to peanut products. A high sensitizing potential can also be postulated for this legume.
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[20] - Sastre J, Fernández-Nieto M, Marañón F, Fernández-Caldas E, Pelta R, Quirce S. Allergenic cross-reactivity between nickel and chromium salts in electroplating-induced asthma. J Allergy Clin Immunol 2001;108:650-651
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[21] - Magni C, Herndl A, Sironi E, Scarafoni A, Ballabio C, Restani P, et al. One- and Two-Dimensional Electrophoretic Identification of IgE-Binding Polypeptides of Lupinus albus and Other Legume Seeds. J Agric Food Chem 2005;53:4567-4571
The prevalence of food allergies in the world population requires integrated approaches to identify new potential allergens, especially those of plant origin. The aim of this work was the allergen in vitro analysis of Lupinus albus seed proteome, a promising food protein source, and the assessment of IgE cross-reactivities with other more diffused legume species. A combination of one- and two-dimensional gel electrophoresis and immunoblotting analyses with specific IgGs for band identification and lupin-sensitized patients' circulating IgEs for allergenicity studies has been used. Two lupin proteins, namely, conglutin gamma and 11S globulin basic subunits, strongly reacted with all patients' sera. Also, cross-reactivities with the homologous polypeptides of other legume species were observed. Otherwise, no reaction at all was detected with a 2S-type lupin protein. This global electrophoretic approach has allowed the identification of a new potential lupin allergen and confirmed the cross-reactivity among the legume 11S globulin basic subunits.
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[22] - Shaw J, Roberts G, Grimshaw K, White S, Hourihane J. Lupin allergy in peanut-allergic children and teenagers. Allergy 2008;63:370-373
BACKGROUND: Lupin has now been introduced into food production in the UK. There is a concern that, on account of cross-reactivity, peanut-allergic children are at high risk for lupin allergy. AIMS: To investigate the prevalence of lupin sensitization and allergy in children with peanut allergy compared with atopic controls . METHODS: Children (<18 years) were recruited. Peanut-allergic subjects either had a convincing history of peanut allergy with diagnostic peanut skin prick test (SPT) or specific-immunoglobulin E (IgE) results or a positive food challenge. Control subjects were atopic but not peanut-allergic. All subjects had SPT to peanut and lupin. Sensitized subjects were offered a randomized, double-blind, placebo-controlled lupin challenge. Lupin allergy was defined as objective immediate hypersensitivity reaction at food challenge . RESULTS: Forty-seven peanut-allergic children and 46 atopic controls were recruited. Sixteen peanut-allergic children were sensitized to lupin [34%, 95% confidence interval (CI): 21-49%]. Nine were challenged to lupin. Two reacted (itchy mouth and urticaria; itchy mouth and 20% drop in peak expiratory flow rate) giving a minimum prevalence of lupin allergy in peanut-allergic children of 4.0% (95% CI: 1-15%). Atopic controls were significantly (P = 0.001) less likely to be sensitized to lupin (4%, 95% CI: 1-15%) and had smaller wheals and serum-specific IgE results. None of the atopic controls reacted on lupin challenge, giving a rate of allergy in the atopic controls of 0% (95% CI: 0-8%) . CONCLUSIONS: A small but significant number of children with peanut allergy are allergic to lupin. Sensitization to lupin is much rarer in nonpeanut-allergic atopic subjects.
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[23] - 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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[24] - Parisot L, Aparicio C, Moneret-Vautrin DA, Guérin L. Allergy to lupine flour. Allergy 2001;56:918-919
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[25] - Alvarez-Alvarez J, Guillamon E, Crespo JF, Cuadrado C, Burbano C, Rodriguez J, et al. Effects of extrusion, boiling, autoclaving, and microwave heating on lupine allergenicity. J Agric Food Chem 2005;53:1294-1298
Lupine flour has been reported as a causative agent of allergic reactions. However, the allergenicity of lupine after thermal processing is not well-known. For this purpose, the allergenic characteristics of lupine seeds after boiling (up to 60 min), autoclaving (121 degrees C, 1.18 atm, up to 20 min and 138 degrees C, 2.56 atm, up to 30 min), microwave heating (30 min), and extrusion cooking were studied. The IgE-binding capacity was analyzed by IgE-immunoblotting and CAP inhibition using a serum pool from 23 patients with lupine-specific IgE. Skin testing was carried out in four patients. An important reduction in allergenicity after autoclaving at 138 degrees C for 20 min was observed. IgE antibodies from two individual sera recognized bands at 23 and 29 kDa in autoclaved samples at 138 degrees C for 20 min. Autoclaving for 30 min abolished the IgE binding to these two components. A previously undetected band at 70 kDa was recognized by an individual serum. Therefore, prolonged autoclaving might have an important effect on the allergenicity of lupine with the majority of patients lacking IgE reactivity to these processed samples.
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[26] - Duranti M, Gius C, Sessa F, Vecchio G. The saccharide chain of lupin seed conglutin gamma is not responsible for the protection of the native protein from degradation by trypsin. Eur J Biochem 1995;230:886-891
Native glycosylated and enzymically deglycosylated conglutin gamma (a lupin seed oligomeric protein) both showed an unusual resistance to tryptic degradation. The result of this treatment was that a single 40-residue peptide was cleaved from the N-terminus of conglutin gamma light subunit. Acid treatment of the two protein forms led to their substantial unfolding, as indicated by CD spectra. After this treatment, both polypeptides were completely degraded by trypsin after a few minutes of incubation. Conversely, trypsin pulse experiments run under renaturing conditions demonstrated a different refolding behaviour of the two proteins: the glycosylated form became resistant to trypsin after a 7-h renaturation, while the deglycosylated form required 42 h renaturation. These results were confirmed by CD spectra and reverse-phase HPLC analyses of the glycosylated and deglycosylated conglutin gamma forms. Therefore, it was concluded that the saccharide chain of conglutin gamma increased the rate of formation of a trypsin-resistant conformation upon refolding of the acid-treated protein, without playing any direct role in the protection of the native protein from proteolysis.
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