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La banane
lundi 12 avril 2010, par
Malgré sa très large consommation, la banane est à l’origine d’un nombre relativement réduit d’accidents allergiques sévères :
– Pumphrey révèle 1 cas parmi 63 anaphylaxies alimentaires fatales 
– le réseau d’Allergo-Vigilance donne 8 cas parmi 900 déclarations (cf. tableau des déclarations du RAV).
La banane est classiquement un fruit associé à l’allergie au latex (cf. latex et aliments). Mais son statut est plus complexe et une allergie à la banane peut recouvrir différentes étiologies .
Ainsi, Somoza note seulement 9 allergies au latex parmi 23 patients allergiques à la banane . Et Snchez-Monge aucun parmi 36 enfants avec une histoire clinique positive pour la banane .
Et Reindl montre que la profiline de banane (Mus xp 1) est positive chez 44 % des allergiques à la banane sans allergie au latex.
On est donc en présence de 2 cadres immunologiques (au moins) :
– une sensibilisation de "type latex" avec positivité pour chitinase/domaine hévéine
– une sensibilisation profilinique
Ce statut mixte rend l’enquête étiologique importante car les réactions cliniques sont volontiers plus sérieuses en cas de sensibilisation aux chitinases plutôt qu’aux profilines.
La banane ne semblant pas être un fruit du "syndrôme LTP" , l’expression clinique d’une réactivité profilinique se verra chez des sujets polliniques et en l’absence des influences majeures que sont le bouleau ou le latex.
C’est avant tout en milieu méditerranéen qu’ont été décrits ces tableaux. Mais cela s’applique très vraisemblablement aux séries américaines associant ambroisie, melon et banane bien que ces travaux soient couramment cités comme une allergie croisée spécifique de l’ambroisie.
Les allergènes de la banane :
La chitinase a été repérée par des équipes françaises avant d’être identifiée en 1999 .
Dans le fruit mûr on trouve, en plus de la chitinase et de la profiline :
- une thaumatin-like protein (TLP) d’environ 20 kDa, non glycosylée , et IgE-réactive . Cette TLP montre une assez bonne résistance à la digestion gastrique .
- Du fait de la bonne homologie entre la TLP de banane et celle du kiwi (Act d 2, 77 % d’identité), la relation banane-kiwi mériterait d’être éclaircie.
- l’homologie est plus modeste avec les TLP de pomme (Mal d 2, 40 %), de cerise (Pru av 2, 43 %), de poivron (Cap a 2, 48 %) et de genévrier (Jun a 3, 55 %) .
- un lien entre pollinose aux cupressacées et allergie au kiwi a été évoqué
- une beta 1,3 glucanase de 31 kDa , IgE-réactive et croisant avec le domaine N-terminal d’Ole e 9 (pollen d’olivier) .
- Cette enzyme est non glycosylée .
- Sa réactivité croisée avec Hev b 2 dans le latex a été étudiée et certains épitopes semblent être croisants .
- Cette enzyme est non glycosylée
- une lectine de 15 kDa, très résistante à la digestion et dont l’IgE-réactivité doit être précisée.
- une isoflavone réductase repérée par réactivité croisée et dont l’allergénicité reste aussi à établir.
- récemment une étude pédiatrique a évoqué de nouvelles protéines IgE-réactives : une chitinase de classe 3, une LTP et une superoxyde dismutase. Le rôle d’une LTP dans l’allergénicité de la banane est cependant réfuté par Asero .
Les contenus en protéines varient dans la banane en fonction de la maturité du fruit.
On utilise l’éthylène pour le mûrissement final des bananes, juste avant commercialisation. Ce traitement provoque un burst de polygalacturonase, de pectate lyase, etc… , mais aussi d’endochitinase, de beta 1,3 glucanase et de TLP .
Banane et CCD
(voir aussi : Les CCD)
La banane n’échappe pas à la présence des glycoprotéines susceptibles d’être reconnues par des IgE anti-CCD .
Bien qu’étant une monocotylédone comme les graminées, la banane présente peu de chaines de type MUXF (celui de la broméline), mais surtout des Lewis a .
Malgré tout, les tests in vitro sont à risque d’être interférés en présence d’IgE anti-CCD dans le sérum .
[1] - Pumphrey RS. Fatal anaphylaxis in the UK, 1992-2001. Novartis Found Symp 2004;257:116-128
Each year in the UK, around nine deaths are attributed to anaphylaxis to pharmaceuticals, six to food and four to stings. I have identified 214 deaths associated with anaphylaxis, and have sufficient information for 196 to determine that 88 deaths were due to shock, 96 to asphyxia. Five deaths followed epinephrine overdose, seven were complicated by disseminated intravascular coagulation. There will have been other unrecognized fatal antibiotic and asthmatic food reactions. For foods, peak age was 17-27 with a female and atopic predominance; the first arrest was commonly from asthma 25-35 minutes after the implicated food. For stings, peak age was 45-70 with male and non-atopic predominance; death was commonly from shock 10-15 minutes after the sting. A majority of deaths from pharmaceuticals in hospital took 5 minutes or less from dose to arrest; peak age was 60-75. Maximum time for any cause from trigger to first arrest was 6 hours. The danger of epinephrine overdose and its limitations in reversing anaphylaxis must be recognized. The patient should remain supine with legs raised throughout sting and other shock reactions. Prevention of fatal food reactions will depend on avoidance and optimal daily control of asthma.
↩[2] - M'Raihi ML, Charpin D, Pons A, Bongrand P, Vervloet D. Allergénicité croisée entre latex et banane. Rev Fr Allergol Immunol Clin 1989;29:187-189 ↩
[3] - Makinen-Kiljunen S. Banana allergy in patients with immediate-type hypersensitivity to natural rubber latex. J Allergy Clin Immunol 1994;93:990-996
BACKGROUND: An association between allergy to latex and banana has been reported. Even though cross-reacting IgE antibodies have been demonstrated, in no study has the existence of structurally similar allergens been confirmed. In the present study banana allergy was studied in a large series of patients with latex allergy. Specific IgE antibodies were characterized for cross-reactivity and compared with pollen RAST results. Latex and banana extracts were investigated for common antigens and allergens .
METHODS: Latex-, banana-, and pollen-specific (birch, timothy, mugwort) IgE were measured in 47 sera from patients with latex allergy. Thirty-one patients were skin prick tested with banana and questioned for possible reactions after eating bananas. Several RAST inhibition and immunospot inhibition studies were used to characterize cross-reacting IgE antibodies. Structurally similar antigens and allergens were evaluated with crossed-line immunoelectrophoresis and crossed-line radioimmunoelectrophoresis, respectively .
RESULTS: Latex RAST results were positive in 31 (66%) and banana RAST results were positive in 26 (55%) of the 47 sera. Of the 31 latex RAST-positive sera, 25 (81%) were also banana RAST-positive. Results from latex RAST correlated significantly with results from banana RAST (p < 0.001), but not with those from pollen RAST (p > 0.05). Banana skin prick test results were positive in 11 (35%) of the 31 patients tested. Symptoms after eating bananas were reported by 16 (52%) of the 31 patients. In inhibition studies the binding of IgE antibodies to solid-phase banana and to several latex preparations was inhibited by latex and banana, respectively. In crossed-line immunoelectrophoresis at least one antigen from banana fused with an antigen from latex, which also bound IgE antibodies in autoradiography (crossed-line radioimmunoelectrophoresis) .
CONCLUSIONS: Patients with latex allergy have symptoms caused by banana and show positive skin test and specific IgE test results. Cross-reacting IgE antibodies were confirmed by several inhibition techniques. For the first time, a structurally similar antigen/allergen was demonstrated.
↩[4] - Alenius H, Makinen-Kiljunen S, Ahlroth M, Turjanmaa K, Reunala T, Palosuo T. Crossreactivity between allergens in natural rubber latex and banana studied by immunoblot inhibition. Clin Exp Allergy 1996;26:341-348
An association between allergic reactions to natural rubber latex and to banana has been reported but the immunochemical properties of the putative cross-reacting allergens remain unknown. OBJECTIVE: To study extracts of banana and natural rubber latex and sera from latex-allergic patients for possible crossreacting allergens and IgE antibodies.
METHODS: Sera from 22 latex-allergic patients and 22 control subjects with no evidence of allergy to latex or to banana were studied. All patients had positive and controls negative reactions in skin-prick testing using an eluate of latex gloves. IgE antibodies to natural rubber latex and to banana were evaluated by immunoblotting and by radioallergosorbent test (RAST) and crossreactivity between allergens in banana and natural rubber latex by immunoblot inhibition. Skin-prick testing was used to examine in vivo reactivity to banana.
RESULTS: Ten of the 22 (45%) latex-allergic patients sera recognized altogether 14 allergens in banana by immunoblotting. The most frequently identified banana allergens were 23, 32, 36, 39 and 47 kDa proteins. The banana skin-prick test was positive in 14 of 18 (78%) latex-allergic patients studied and banana RAST in 12 of 14 patient sera tested. Fourteen of 21 interviewed patients reported symptoms from eating or handling bananas. In immunoblot inhibition studies a dose-dependent inhibition of IgE binding to banana extract with natural rubber latex proteins was observed in all five patient sera tested and, likewise, the binding of IgE to natural rubber latex extract was inhibited with banana proteins in four of the five patient sera.
CONCLUSIONS: The present results confirm the existence of crossreacting allergens in natural rubber latex and banana and provide new information on the immunochemical nature and heterogeneity of these allergens.
↩[5] - Grob M, Reindl J, Vieths S, Wuthrich B, Ballmer-Weber BK. Heterogeneity of banana allergy: characterization of allergens in banana-allergic patients. Ann Allergy Asthma Immunol 2002;89:513-516
BACKGROUND: Banana is a frequent cause of food allergy, particularly in latex-sensitized patients. OBJECTIVE: The aim of the study was to get insights in immunoglobulin (Ig)E antibody responses of patients with a history of allergic reaction to banana but not to latex.
METHODS: In four patients who complained about symptoms after banana consumption, skin prick tests (SPTs) with aeroallergens, latex, banana, avocado, and kiwi were performed. Total and specific serum IgE to birch pollen, rBet v 1 and rBet v 2, latex, banana, avocado, and kiwi were determined by the CAP method (Pharmacia Diagnostics, Uppsala, Sweden). Allergens were identified by immunoblotting with banana extract and recombinant banana profilin. Two patients underwent double-blind, placebo-controlled food challenges (DBPCFC) with banana.
RESULTS: All patients showed a positive SPT to banana, and three were IgE-CAP positive (> or = class 2). Two patients were also sensitized (SPT and CAP) to latex, avocado, kiwi, and birch pollen. In the immunoblot these two patients' sera reacted to 32- to 34-kDa proteins, which had already been described as major banana allergens. In both patients banana allergy was confirmed by DBPCFC. The third patient also had a sensitization to avocado, but not to latex or pollen. Immunoblot analysis detected a single band at 70 kDa. The fourth patient was sensitized to birch pollen, rBet v 1 and rBet v 2, but not to latex. Immunoblot analysis in this patient's serum was positive with recombinant banana profilin.
CONCLUSIONS: The relevance of banana as a source of food allergy was confirmed in two patients by DBPCFC. In 1 of 2 patients, in whom banana allergy was not a consequence of latex sensitization, a 70-kDa protein was identified as a banana allergen, and in the other patient profilin was detected as a putative cross-reactive allergen.
↩[6] - Ito A, Ito K, Morishita M, Sakamoto T. A banana-allergic infant with IgE reactivity to avocado, but not to latex. Pediatr Int 2006;48:321-323 ↩
[7] - Somoza ML, Rico P, Feliu A, Jiménez A, Rodriguez J, Crespo JF. Banana allergy confirmed by double-blind placebo-controlled food challenge (DBPCFC). EAACI 22th Congress, Paris, 7-11 June, 2003, Poster n°132
Background: Banana, a member of the Musaceae family, is widely consumed all over the world. It is available almost all year round in temperate climates due to heavy exporting from banana-growing countries. Banana allergy has been reported mainly associated to latex allergy. The aim of the study was to investigate clinical features of acute allergic reactions to banana confirmed by double-blind, placebo-controlled, food challenge (DBPCFC).
Methods: Case series of 23 adult patients diagnosed with clinical banana allergy in the Food Allergy Unit from 'Hospital Universitario 12 de Octubre' (Madrid). Diagnostic procedure including a clinical questionnaire, skin testing by prick-prick with fresh fruit and detection of specific IgE (CAP FEIA) were performed in all patients reporting adverse reactions to foods. Patients first underwent an open food challenge (OFC), unless they had a convincing history of severe anaphylaxis. Positive OFC reactions were subsequently evaluated by DBPCFCs. All negative results of DBPCFCs were followed by an open feeding.
Results: The age of patients ranged from 10 to 66 yr. (median= 24 yr.) with a female/male ratio of 2.8. Most patients (62%) experienced multiple allergic reactions after banana ingestion before being diagnosed with banana allergy. The most common clinical manifestation was the oral allergy syndrome (52%), followed by gastrointestinal anaphylaxis (8%) and acute respiratory symptoms (8%). The results of allergy testing were positive in 94% of the patients; however, an IgE-mediated mechanism could not be demostrated in two patients. In addition, 54 adverse reactions to other 20 different foods of vegetable origin were confirmed by DBPCFC‚s in the banana allergic patients; including melon, 12 patients; chestnut, 6 pt.; and avocado and kiwi, 5 pt. each. Latex allergy was diagnosed in 8 out of 23 (35%). Seventy-eight percent of the patients had pollen allergy.
Conclusions: Banana can induce severe anaphylaxis, although most adverse reactions consist of oral allergy syndrome. Isolated banana allergy is uncommon, being associated frequently to melon allergy and latex allergy.
↩[8] - Sanchez-Monge R, Quirce S, Bobolea I, Pascual C, Diaz Perales A, Salcedo G. Identification of major banana allergens in pediatric patients. Allergy 2009;64(Suppl. 90):47
Background: Banana allergy is currently view as a class 2 food allergy, being latex and pollens the main sensitizing agents. Class I chitinases and profilin have been characterized as allergens responsible of these cross-reactions. However banana allergy is increasing in the paediatric population and its development seems to be, in some cases, independent of pollen sensitization. We ought to investigate the banana allergens implicated in paediatric banana allergy.
Methods: Thirty six children (range 6 months to 6 years of age) with clinical symptoms after the ingestion of banana were selected. Specific IgE to banana, other foods, several pollens and latex was measured by Pharmacia CAP System FEIA. IgE immunodetection of a banana protein extract using a serum pool and individual sera were performed. Main IgE binding proteins were purified by affinity, ion-exchange and HPLC chromatography and characterized by N-terminal sequencing and fingerprinting. Specific IgE of individual sera to the purified proteins was determinated by ELISA assays.
Results: Most of the selected banana allergic children were also sensitized to other foods and 50% of them showed pollinosis. None of them have allergy to latex, although some have latex positive CAP. Thaumatin, ß-1,3-glucanase and class III chitinase were detected as potentially relevant IgE-binding proteins from banana extract. Additionally, a non-specific lipid binding protein (LTP) and a superoxide dismutase were recognized by 20% of the sera.
Conclusions: Banana allergy in children can be a primary allergy independent of latex and pollen allergy. Several putative banana allergens seem to be plant defence proteins, such as thaumatins, glucanases and chitinases, with possible implications in latex and pollen cross-reactions.
↩[9] - Reindl J, Rihs HP, Scheurer S, Wangorsch A, Haustein D, Vieths S. IgE Reactivity to Profilin in Pollen-Sensitized Subjects with Adverse Reactions to Banana and Pineapple. Int Arch Allergy Immunol 2002;128:105-114
Background: The so-called 'latex-fruit syndrome' is a well-documented phenomenon in cross-reactive allergies. By contrast, there is a lack of information about allergy to exotic fruits in patients with a predominant pollen sensitization. Since the ubiquitous protein profilin has been identified as an allergen in natural rubber latex as well as in pollen-related foods, the aim of this study was to investigate the role of profilin in allergy to certain exotic fruits.
Methods: Recombinant profilins from banana and pineapple were cloned by a PCR technique after isolation of total RNA using degenerated profilin-specific primers. The unknown 5' ends of copy DNA (cDNA) were identified by rapid amplification of 5'cDNA ends (5'-RACE) and expression in Escherichia coli BL21(DE3) cells. The recombinant profilins were purified by affinity chromatography using poly-(L)-proline as the solid phase. IgE-binding capabilities were characterized by means of immunoblot and Enzyme Allergosorbent Test (EAST). The cross-reactivity to birch pollen profilin and latex profilin was studied by EAST as well as by immunoblot inhibition experiments.
Results: Both banana and pineapple profilin were found to consist of 131 amino acid residues with high amino acid sequence identity to known allergenic pollen and food profilins (71-84%). IgE binding to the recombinant profilins was observed in 7/16 sera from subjects with suspected banana allergy (44%) and in 8/19 sera from subjects with suspected pineapple allergy (42%). Inhibition experiments indicated similar IgE reactivity of natural and recombinant allergens. In addition, high cross-reactivity to birch pollen profilin Bet v 2 and latex profilin Hev b 8 was demonstrated by immunoblot inhibition as well as EAST inhibition experiments.
Conclusions: Since a high IgE-binding prevalence of about 40% was obtained in both banana and pineapple allergy, we conclude that profilin is an important mediator of IgE cross-reactivity between pollen and exotic fruits
↩[10] - Asero R, Mistrello G, Roncarolo D, Amato S. Detection of Some Safe Plant-Derived Foods for LTP-Allergic Patients. Int Arch Allergy Immunol 2007;144:57-63
BACKGROUND: Lipid transfer protein (LTP) is a widely cross-reacting plant pan-allergen. Adverse reactions to Rosaceae, tree nuts, peanut, beer, maize, mustard, asparagus, grapes, mulberry, cabbage, dates, orange, fig, kiwi, lupine, fennel, celery, tomato, eggplant, lettuce, chestnut and pineapple have been recorded .
OBJECTIVE: To detect vegetable foods to be regarded as safe for LTP-allergic patients .
METHODS: Tolerance/intolerance to a large spectrum of vegetable foods other than Rosaceae, tree nuts and peanut was assessed by interview in 49 subjects monosensitized to LTP and in three distinct groups of controls monosensitized to Bet v 1 (n = 24) or Bet v 2 (n = 18), or sensitized to both LTP and birch pollen (n = 16), all with a history of vegetable food allergy. Patients and controls underwent skin prick test (SPT) with a large spectrum of vegetable foods. The absence of IgE reactivity to foods that were negative in both clinical history and SPT was confirmed by immunoblot analysis and their clinical tolerance was finally assessed by open oral challenge (50 g per food) .
RESULTS: All patients reported tolerance and showed negative SPT to carrot, potato, banana and melon; these foods scored positive in SPT and elicited clinical symptoms in a significant proportion of patients from all three control groups. All patients tolerated these four foods on oral challenge. Immunoblot analysis confirmed the lack of IgE reactivity to these foods by LTP-allergic patients .
CONCLUSION: Carrot, potato, banana and melon seem safe for LTP-allergic patients. This finding may be helpful for a better management of allergy to LTP.
↩[11] - Enberg RN, Leickly FE, McCullough J, Bailey J, Ownby DR. Watermelon and ragweed share allergens. J Allergy Clin Immunol 1987;79:867-875
A biotin-avidin amplified ELISA was used to measure antigen-specific IgE for ragweed, representative members of the gourd family (watermelon, cantaloupe, honeydew melon, zucchini, and cucumber), and banana in the sera of 192 allergic patients, each with an IgE greater than or equal to 180 microns/ml. Sixty-three percent (120/192) of the sera contained antiragweed IgE, and of these patients, 28% to 50% contained IgE specific for any single gourd family member. In contrast, no greater than 11% of the sera positive for a given gourd or banana were negative for ragweed. Correlations between ragweed and gourd-specific IgE levels were significant (p less than 0.001), and correlation coefficients between any two gourds exceeded 0.79. In an ELISA system, the extracts of watermelon and ragweed inhibited each other in a dose-dependent manner; the resulting nonparallel inhibition curves indicate that some, but not all, of the allergens in the two extracts are cross-reactive. Isoelectric focusing of watermelon and ragweed extracts in narrow range gel (pH 4 to 6) followed by immunoblotting demonstrated six watermelon allergen bands with isoelectric points identical to those of ragweed allergens. Several remaining bands in the two extracts had differing isoelectric points, however. Six of 26 patients interviewed with watermelon-specific IgE reported developing oropharyngeal symptoms (itching and/or swelling of the lips, tongue, or throat) after ingesting at least one of the study foods, whereas only one of 25 patients interviewed without detectable watermelon-specific IgE reported similar symptoms (p = 0.05)
↩[12] - Anderson LB Jr, Dreyfuss EM, Logan J, Johnstone DE, Glaser J. Melon and banana sensitivity coincident with ragweed pollinosis. J Allergy 1970;45:310-319 ↩
[13] - Delbourg MF, Guilloux L, Moneret-Vautrin DA, Ville G. Hypersensitivity to banana in latex-allergic patients. Identification of two major banana allergens of 33 and 37 kD. Ann Allergy Asthma Immunol 1996;76:321-326
Allergy to banana often occurs in patients sensitized to latex. The spectrum of IgE-mediated responses to latex allergens is more and more documented but banana allergens and epitopes shared by these two allergens have not yet been characterized, even though the existence of cross-reacting IgE antibodies has been demonstrated. OBJECTIVE: The purpose of this study was to assess the relationship between banana hypersensitivity and latex allergy in a population of 19 latex-allergic patients and to identify allergenic components in banana and the common structures shared with latex.
METHODS: The in vivo study was conducted in our outpatient department in patients with well-documented latex allergy. Clinical histories were evaluated and skin prick tests were performed with banana and latex extracts. IgE responses from 19 patients were investigated by means of CAP RAST assay and SDS PAGE immunoblotting. Epitopes shared by banana and latex were investigated by means of immunoblotting experiments.
RESULTS: Eight of 16 patients (50%) reported symptoms after eating bananas and banana skin prick tests were positive in 5 of 14 patients (36%). Banana RAST results were positive in 12 of the 19 patients (63%). In immunoblot experiments, 17 of the 19 patients (89%) exhibited specific banana IgE antibodies and 16 allergenic components were identified with molecular weights ranging from 17 to 128 kD. Two were considered as major allergens: 33 kD was detectable in 15 of 19 sera (88%) and 37 kD in 13 of 19 sera (76%). Inhibition studies by preincubation of two individual sera with banana or latex extract demonstrated the complete disappearance of IgE binding on banana blotted allergens. CONCLUSION: This study confirms the "latex-fruit syndrome" already described by Blanco et al. Two major allergens were revealed in banana at 33 and 37 kD and the presence of more than ten common components with latex was observed.
↩[14] - Lavaud F, Prévost A, Cossart C, Guérin L, Bernard J, Kochman S. Allergy to latex, avocado pear, and banana: evidence for a 30 kd antigen in immunoblotting. J Allergy Clin Immunol 1995;95:557-564
Allergens of natural latex, latex gloves, avocado pear, and banana extracts were investigated by an immunoblotting technique in sera of patients experiencing associated latex and fruit allergies. Extracts were separated by sodium dodecyl-sulfate-polyacrylamide gel electrophoresis and electroblotted onto nitrocellulose. After incubation with patients' sera, IgE antibodies were revealed by a goat anti-human IgE alkaline-phosphatase conjugate. Seventeen serum samples from patients with well-documented latex allergy were studied. Among these patients, 10 demonstrated an allergy to avocado pear sometimes associated with banana. In sera from patients with latex and fruit allergy, prominent IgE binding was revealed at about 30 kd with latex and fruit extracts. Serum controls remained negative. Cross-inhibition of immunoblotting confirmed that this main allergen is linked to a common epitope present in latex and fruits. This must be related to clinical findings and previous observations of cross-reactivity.
↩[15] - Sanchez-Monge R, Blanco C, Diaz-Perales A, Collada C, Carrillo T, Aragoncillo C, et al. Isolation and characterization of major banana allergens: identification as fruit class I chitinases. Clin Exp Allergy 1999;29:673-680
BACKGROUND: Banana allergy has been associated with the latex-fruit syndrome. Several IgE-binding components, the relevant ones being proteins of 30-37-kDa, have been detected in banana fruit, but none of them have been isolated and characterized yet. Objective To purify and characterize the 30-37 kDa banana allergens.
METHODS: Fifteen patients allergic to banana were selected on the grounds of a latex-allergic population. Prick by prick tests to this fruit were performed. Total and specific IgE to banana were determined. Banana allergens were isolated by affinity chromatography, followed by cation-exchange chromatography. Their characterization includes N-terminal sequencing, enzymatic activity assays, immunodetection with sera from allergic patients and with antichitinase antibodies, and CAP and immunoblot inhibition tests. Skin prick tests with banana extracts and with the purified allergens were also carried out.
RESULTS: Two major IgE-binding proteins of 34 and 32 kDa, also recognized by polyclonal antibodies against chestnut chitinases, were immunodetected in crude banana extracts. Purification and characterization of both proteins have allowed their identification as class I chitinases with an hevein-like domain. Each isolated allergen reached inhibition values higher than 90% in CAP inhibition assays, and fully inhibited the IgE-binding by the crude banana extract when tested by an immunoblot inhibition method. The two purified allergens provoked positive skin prick test responses in more than 50% of the banana-allergic patients.
CONCLUSIONS: Class I chitinases with an hevein-like domain are major allergens in banana fruit. Their presence in other fruits and nuts, such as avocado and chestnut, could explain the cross-sensitization among these foods.
↩[16] - Peumans WJ, Proost P, Swennen RL, van Damme EJM. The abundant class III chitinase homolog in young developing banana fruits behaves as a transient vegetative storage protein and most probably serves as an important supply of amino acids for the synthesis of ripening-associated proteins. Plant Physiol 2002;130:1063-1072
AB: Analyses of the protein content and composition revealed dramatic changes in gene expression during in situ banana (Musa spp. [M. acuminata] cv. Grande Naine) fruit formation/ripening. The total banana protein content rapidly increased during the first 60 to 70 days, but remained constant for the rest of fruit formation/ripening. During the phase of rapid protein accumulation, an inactive homologue of class III chitinases accounted for up to 40% (w/v) of the total protein. Concomitant with the arrest of net protein accumulation, the chitinase-related protein (CRP) progressively decreased and several novel proteins appeared in the electropherograms. Hence, CRP behaved as a fruit-specific vegetative storage protein that accumulated during early fruit formation and served as a source of amino acids for the synthesis of ripening-associated proteins. Analyses of individual proteins revealed that a thaumatin-like protein, a beta-1,3-glucanase, a class I chitinase, and a mannose-binding lectin were the most abundant ripening-associated proteins. Because during the ripening of prematurely harvested bananas, similar changes transpired as in the in situ ripening bananas, CRP present in immature fruits was a sufficient source of amino acids for a quasi-normal synthesis of ripening-associated proteins. However, it is evident that the conversion of CRP in ripening-associated proteins took place at an accelerated rate, especially when climacteric ripening was induced by ethylene. The present report also includes a discussion of the accumulation of the major banana allergens and the identification of suitable promoters for the production of vaccines in transgenic bananas.
------------------------------------------------------- Koshte VL, Aalbers M, Calkhoven PG, Aalberse RC.
The potent IgG4-inducing antigen in banana is a mannose-binding lectin, BanLec-I Int Arch Allergy Immunol. 1992;97(1):17-24 IgG4 antibodies to banana were found to occur far more frequently than expected. The most important antigen involved proved to be a lectin, BanLec-I. Because of the lectin nature of the antigen, it was important to establish the antibody nature of the lectin-IgG4 interaction and to exclude an interaction between the sugar-binding site of the lectin and glycosidic chains on IgG4. Three arguments in support of immune binding are: (1) the binding of BanLec-I to IgG4 is mannoside resistant, whereas the binding to all other glycoproteins tested is mannoside inhibitable; (2) only a minor fraction of the IgG4 in serum and none of five IgG4 myelomas tested was bound, and (3) the lectin binds to the Fab fragment of the IgG4 molecule. A curious finding was that in the presence of high-molecular-weight glycoproteins the interaction between IgG4 and BanLec-I was enhanced by alpha-methyl mannoside. The probable explanation of this phenomenon is that complexes of the lectin with high-molecular-weight glycoproteins by sterical interference inhibit the interaction with human IgG4 antibodies (or with rabbit antibodies to the lectin). This inhibition is prevented in the presence of alpha-methyl mannoside. These results support the earlier suggestion that some lectins are particularly prone to induce an immune response upon oral feeding. This banana lectin might be a potentially useful carrier protein for oral antihapten immunization in humans.
↩[17] - Leone P, Menu-Bouaouiche L, Peumans WJ, Payan F, Barre A, Roussel A, et al. Resolution of the structure of the allergenic and antifungal banana fruit thaumatin-like protein at 1.7-A. Biochimie 2006;88:45-52
The structure of a thaumatin-like protein from banana (Musa acuminata) fruit, an allergen with antifungal properties, was solved at 1.7-A-resolution, by X-ray crystallography. Though the banana protein exhibits a very similar overall fold as thaumatin it markedly differs from the sweet-tasting protein by the presence of a surface exposed electronegative cleft. Due to the presence of this electronegative cleft, the banana thaumatin-like protein (Ban-TLP) acquires a strong (local) electronegative character that eventually explains the observed antifungal activity. Our structural analysis also revealed the presence of conserved residues of exposed epitopic determinants that are presumably responsible for the allergenic properties of banana fruit towards susceptible individuals, and provided evidence that the Ban-TLP shares some structurally highly conserved IgE-binding epitopes with thaumatin-like proteins from fruits or pollen from other plants. In addition, some overlap was detected between the predicted IgE-binding epitopes of the Ban-TLP and IgE-binding epitopes previously identified in the mountain cedar Jun a 3 TLP aeroallergen. The presence of these common epitopes offers a molecular basis for the cross-reactivity between aeroallergens and fruit allergens.
↩[18] - Jimenez-Bermudez S, Redondo-Nevado J, Munoz-Blanco J, Caballero JL, Lopez-Aranda JM, Valpuesta V, et al. Manipulation of strawberry fruit softening by antisense expression of a pectate lyase gene. Plant Physiol 2002;128:751-759
Strawberry (Fragaria x ananassa, Duch., cv Chandler) is a soft fruit with a short postharvest life, mainly due to a rapid lost of firm texture. To control the strawberry fruit softening, we obtained transgenic plants that incorporate an antisense sequence of a strawberry pectate lyase gene under the control of the 35S promoter. Forty-one independent transgenic lines (Apel lines) were obtained, propagated in the greenhouse for agronomical analysis, and compared with control plants, non-transformed plants, and transgenic lines transformed with the pGUSINT plasmid. Total yield was significantly reduced in 33 of the 41 Apel lines. At the stage of full ripen, no differences in color, size, shape, and weight were observed between Apel and control fruit. However, in most of the Apel lines, ripened fruits were significantly firmer than controls. Six Apel lines were selected for further analysis. In all these lines, the pectate lyase gene expression in ripened fruit was 30% lower than in control, being totally suppressed in three of them. Cell wall material isolated from ripened Apel fruit showed a lower degree of in vitro swelling and a lower amount of ionically bound pectins than control fruit. An analysis of firmness at three different stages of fruit development (green, white, and red) showed that the highest reduction of softening in Apel fruit occurred during the transition from the white to the red stage. The postharvest softening of Apel fruit was also diminished. Our results indicate that pectate lyase gene is an excellent candidate for biotechnological improvement of fruit softening in strawberry.
↩[19] - Payasi A, Sanwal GG. Pectate lyase activity during ripening of banana fruit. Phytochemistry 2003;63:243-248
Pectate lyase (PEL) activity was demonstrated in ripe banana fruits on supplementing the homogenizing medium with cysteine and Triton X-100. The enzyme was characterized on the basis of alkaline pH optimum, elimination of the activity by EDTA and activation by Ca(2+). PEL activity was not detected in preclimacteric banana fruits. PEL activity increased progressively from early climacteric and reached maximum level at climacteric peak and declined in post climacteric and over ripened fruits. Replacing pectate with pectin in PEL assay manifested enzyme activity even in preclimacteric fruits. In contrast to PEL, polygalacturonase activity progressively increased during fruit ripening even in postclimacteric fruits.
↩[20] - Barre A, Peumans WJ, Menu-Bouaouiche L, Van Damme EJ, May GD, Herrera AF, et al. Purification and structural analysis of an abundant thaumatin-like protein from ripe banana fruit. Planta 2000;211:791-799
The pulp of ripe bananas (Musa acuminata) contains an abundant thaumatin-like protein (TLP). Characterization of the protein and molecular cloning of the corresponding gene from banana demonstrated that the native protein consists of a single polypeptide chain of 200 amino acid residues. Molecular modelling further revealed that the banana thaumatin-like protein (Ban-TLP) adopts an overall fold similar to that of thaumatin and thaumatin-like PR-5 proteins. Although the banana protein exhibits an electrostatically polarized surface, which is believed to be essential for the antifungal properties of TLPs, it is apparently devoid of antifungal activity towards pathogenic fungi. It exhibits a low but detectable in vitro endo-beta-1,3-glucanase (EC 3.2.1.x) activity. As well as being present in fruits, Ban-TLP also occurs in root tips where its accumulation is enhanced by methyl jasmonate treatment of plants. Pulp of plantains (Musa acuminata) also contains a very similar TLP, which is even more abundant than its banana homologue. Our results demonstrate for the first time that fruit-specific (abundant) TLPs are not confined to dicots but occur also in fruits of monocot species. The possible role of the apparent widespread accumulation of fruit-specific TLPs is discussed.
↩[21] - Bobic S, Polovic N, Cirkovic Velickovic T, Jankov R, Atanaskovic-Markovic M, Gavrovic-Jankulovic M. Cross-reactivity between thaumatin-like proteins from banana and kiwi fruit: a case report. EAACI 25th Congress, Vienna, 10-14 June, 2006, Poster n°509
Background: Banana was recognized as food allergen about 80 years ago and so far profilin and class I chitinase have been identified as banana allergens. In last few years thaumatin-like proteins have been established as a new allergen family present in pollen and plant food. Thaumatin-like proteins (TLPs) belong to the pathogenesis-related family of proteins with a certain degree of sequence homology among them. There is no report in literature about allergenicity of banana TLP unlike TLPs from other fruits. The aim of this work was to explore possible cross-reactivity of banana and kiwi TLP.
Methods: Banana and kiwi TLP were isolated from fruit extracts by classical biochemical methods. Stability of these proteins has been investigated in conditions of simulated gastric fluid (by US Pharmacopoeia). Monoclonal antibodies produced against kiwi TLP were used for detection of cross-reactive epitopes on banana TLP. Sera from two patients with oral allergy sindrom to banana (f92; 2.12 kU/L) or kiwi TLP were used for in vivo and in vitro analysis. Kiwi TLP positive patient's sera was used for detection of IgE-binding epitopes on banana TLP. Allergenicity of banana TLP was examined in vivo by skin-prick test.
Results: According to Western blot analysis performed with monoclonal antibodies 20 kD banana TLP shares epitopes with kiwi TLP. Additionally, they also share IgE-binding epitopes. Patient with oral allergy sindrom to banana fruit showed positive skin prick test with purified banana TLP. In spite of the structural similarities, the difference of two proteins was noticed in their resistance in the conditions of simulated gastric fluid, since banana TLP revealed resistence upon one hour of incubation.
Conclusion: Banana TLP shares certain structural similarities with the kiwi TLP. Moreover, banana TLP exerts biological activity by bridging cell-bound IgE on efector mast cells. For the relevance of allergenicity of banana TLP a certain number of patients should be included in the clinical study.
Nevertheless banana TLP has the potential to provoke allergic reaction and should be added to the family of PR-5 allergens.
↩[22] - Sanchez-Monge R, Quirce S, Bobolea I, Pascual C, Diaz Perales A, Salcedo G. Identification of major banana allergens in pediatric patients. Allergy 2009;64(Suppl. 90):47
Background: Banana allergy is currently view as a class 2 food allergy, being latex and pollens the main sensitizing agents. Class I chitinases and profilin have been characterized as allergens responsible of these cross-reactions. However banana allergy is increasing in the paediatric population and its development seems to be, in some cases, independent of pollen sensitization. We ought to investigate the banana allergens implicated in paediatric banana allergy.
Methods: Thirty six children (range 6 months to 6 years of age) with clinical symptoms after the ingestion of banana were selected. Specific IgE to banana, other foods, several pollens and latex was measured by Pharmacia CAP System FEIA. IgE immunodetection of a banana protein extract using a serum pool and individual sera were performed. Main IgE binding proteins were purified by affinity, ion-exchange and HPLC chromatography and characterized by N-terminal sequencing and fingerprinting. Specific IgE of individual sera to the purified proteins was determinated by ELISA assays.
Results: Most of the selected banana allergic children were also sensitized to other foods and 50% of them showed pollinosis. None of them have allergy to latex, although some have latex positive CAP. Thaumatin, ß-1,3-glucanase and class III chitinase were detected as potentially relevant IgE-binding proteins from banana extract. Additionally, a non-specific lipid binding protein (LTP) and a superoxide dismutase were recognized by 20% of the sera.
Conclusions: Banana allergy in children can be a primary allergy independent of latex and pollen allergy. Several putative banana allergens seem to be plant defence proteins, such as thaumatins, glucanases and chitinases, with possible implications in latex and pollen cross-reactions.
↩[23] - Bobic S, Polovic N, Cirkovic Velickovic T, Jankov R, Atanaskovic-Markovic M, Gavrovic-Jankulovic M. Cross-reactivity between thaumatin-like proteins from banana and kiwi fruit: a case report. EAACI 25th Congress, Vienna, 10-14 June, 2006, Poster n°509
Background: Banana was recognized as food allergen about 80 years ago and so far profilin and class I chitinase have been identified as banana allergens. In last few years thaumatin-like proteins have been established as a new allergen family present in pollen and plant food. Thaumatin-like proteins (TLPs) belong to the pathogenesis-related family of proteins with a certain degree of sequence homology among them. There is no report in literature about allergenicity of banana TLP unlike TLPs from other fruits. The aim of this work was to explore possible cross-reactivity of banana and kiwi TLP.
Methods: Banana and kiwi TLP were isolated from fruit extracts by classical biochemical methods. Stability of these proteins has been investigated in conditions of simulated gastric fluid (by US Pharmacopoeia). Monoclonal antibodies produced against kiwi TLP were used for detection of cross-reactive epitopes on banana TLP. Sera from two patients with oral allergy sindrom to banana (f92; 2.12 kU/L) or kiwi TLP were used for in vivo and in vitro analysis. Kiwi TLP positive patient's sera was used for detection of IgE-binding epitopes on banana TLP. Allergenicity of banana TLP was examined in vivo by skin-prick test.
Results: According to Western blot analysis performed with monoclonal antibodies 20 kD banana TLP shares epitopes with kiwi TLP. Additionally, they also share IgE-binding epitopes. Patient with oral allergy sindrom to banana fruit showed positive skin prick test with purified banana TLP. In spite of the structural similarities, the difference of two proteins was noticed in their resistance in the conditions of simulated gastric fluid, since banana TLP revealed resistence upon one hour of incubation.
Conclusion: Banana TLP shares certain structural similarities with the kiwi TLP. Moreover, banana TLP exerts biological activity by bridging cell-bound IgE on efector mast cells. For the relevance of allergenicity of banana TLP a certain number of patients should be included in the clinical study.
Nevertheless banana TLP has the potential to provoke allergic reaction and should be added to the family of PR-5 allergens.
↩[24] - Gavrovic-Jankulovic M, Cirkovic T, Vuckovic O, Petrovic-Djergovic D, Atanaskovic-Markovic M, Jankov RM. Partial characterization of basic pepsin-resistant banana allergen. EAACI 22th Congress, Paris, 7-11 June, 2003, Poster n°704
Background: The prevention of severe anaphylactic food reactions demands the identification of food allergens and development of component-resolved diagnostic tests that will improve the diagnosis of food allergy. Resistance to proteolysis is considered to be an important prerequisite determining the allergenicity of food proteins. Banana allergy together with its association with hypersensitivity to other fruits and to latex has been widely reported in the recent years. The aim of this study was to examine digestibility of banana protein extract and its impact on the allergenicity, and to characterize proteins resistant to proteolysis as well.
Methods: Banana protein extract, prepared in ammonium bicarbonate, was characterised by isoelectric focusing (IEF) and SDS-PAGE. The extract was digested in a simulated gastric fluid (SGF) for one hour, according to US Pharmacopeia. The digest was analysed by SDS-PAGE and size-exclusion chromatography (Superdex 75). Banana resistant protein was isolated by reversed phase chromatography (mRPC C2/C18), and analysed by two-dimensional (2D) PAGE. IgE-binding of the banana extract and SGF resistant banana proteins was shown in Western blot, with a pool of sera from three patients with "latex-fruit" syndrome.
Results: Prepared banana extract reveals almost twenty protein bands in a range of 70 to 15 kD in SDS-PAGE, and pI about 3.5 to 9.4 in IEF. After one hour of incubation with pepsin the majority of the banana proteins were digested except a protein of about 15 kD. In Western blot banana extract reveals eleven IgE binding molecules, whereas digested mixture reveals only one band of about 15 kD. Isolated pepsin resistant protein reveals one spot of about 15 kD and pI about 9.2 in 2D-PAGE.
Conclusion: Pepsin resistant allergen was isolated from the banana digest by a combination of size-exclusion and reversed phase chromatography. The basic protein has a molecular mass of about 15 kD according to 2D-PAGE. The protein retains structural stability and preserves IgE-binding epitopes after exposure to SGF conditions. According to our results, the resistant allergen resembles to the family of lipid transfer proteins known to exhibit structural stability under digestion.
↩[25] - Leone P, Menu-Bouaouiche L, Peumans WJ, Payan F, Barre A, Roussel A, et al. Resolution of the structure of the allergenic and antifungal banana fruit thaumatin-like protein at 1.7-A. Biochimie 2006;88:45-52
The structure of a thaumatin-like protein from banana (Musa acuminata) fruit, an allergen with antifungal properties, was solved at 1.7-A-resolution, by X-ray crystallography. Though the banana protein exhibits a very similar overall fold as thaumatin it markedly differs from the sweet-tasting protein by the presence of a surface exposed electronegative cleft. Due to the presence of this electronegative cleft, the banana thaumatin-like protein (Ban-TLP) acquires a strong (local) electronegative character that eventually explains the observed antifungal activity. Our structural analysis also revealed the presence of conserved residues of exposed epitopic determinants that are presumably responsible for the allergenic properties of banana fruit towards susceptible individuals, and provided evidence that the Ban-TLP shares some structurally highly conserved IgE-binding epitopes with thaumatin-like proteins from fruits or pollen from other plants. In addition, some overlap was detected between the predicted IgE-binding epitopes of the Ban-TLP and IgE-binding epitopes previously identified in the mountain cedar Jun a 3 TLP aeroallergen. The presence of these common epitopes offers a molecular basis for the cross-reactivity between aeroallergens and fruit allergens.
↩[26] - Kim YS, Park JY, Kim KS, Ko MK, Cheong SJ, Oh BJ. A thaumatin-like gene in nonclimacteric pepper fruits used as molecular marker in probing disease resistance, ripening, and sugar accumulation. Plant Mol Biol 2002;49:125-135
During pepper (Capsicum annuum) fruit ripening, the ripe fruit interaction with the anthracnose fungus, Colletotrichum gloeosporioides, is generally incompatible. However, the unripe fruit can interact compatibly with the fungus. A gene, designated PepTLP (for pepper thaumatin-like protein), was isolated and characterized by using mRNA differential display. The PepTLP gene encodes a protein homologous to other thaumatin-like proteins and contains 16 conserved cysteine residues and the consensus pattern of thaumatin. PepTLP gene expression is developmentally regulated during ripening. The accumulation of PepTLP mRNA and PepTLP protein in the incompatible interaction was higher than that in the compatible one.
Furthermore, PepTLP gene expression was stimulated by both jasmonic acid treatment and wounding during ripening, but by wounding only in the unripe fruit. Immunolocalization studies showed that it is localized to the intercellular spaces among cortical cells. The expression of the PepTLP gene upon fungal infection was a rise from the early-breaker fruit. The development of anthracnose became significantly prevented with beginning of fruit ripening, and the sum total of sugar accumulation increased. The results suggest that the PepTLP gene can be used as a molecular marker in probing for disease resistance, ripening, and sugar accumulation in nonclimacteric pepper fruits.
↩[27] - Sharma GS, Midoro-Horiuti T, van Bavel JH, Goldblum RM. Oral allergy syndrome to tomato, banana, and apple in mountain cedar pollinosis. ACAAI Annual Meeting, New Orleans, 7-12 Nov. 2003, Poster n° 59
Mountain cedar (Juniperus ashei, MC, Cupressaceae) pollen is a major cause of seasonal hypersensitivity in the central US. Some patients with hypersensitivity to other pollen allergens have oral allergy syndrome (OAS), an IgE-mediated reaction of the lips, mouth and pharynx after eating native fruits and vegetables. OAS is thought to be due to IgE anti-pollen antibodies that cross-react with the food allergens. OAS has not been reported in MC pollinosis, but OAS to tomatoes has been described in a few patients with Japanese cedar pollinosis. We performed a mail-out / telephone survey of 800 mountain cedar-sensitive patients in the Austin, TX area. After telephone screening, 28 patients were interviewed, skin tested and had serum collected for serological testing. Of the 28 cedar sensitive patients with suspected food allergies, 15 had clinical manifestations of oral allergy syndrome. Eleven of the 28 subjects had positive skin tests to tomato and 6 of these patients were also positive to banana. Subjects with oral allergy syndrome to tomatoes and bananas tended to have stronger cutaneous and in vitro reactivity to cedar pollen. The intensities of the tomato and banana reactivities were correlated with the intensity of cedar reactivity. Sera from the 11 cedar-sensitive patients with positive skin tests to tomato were tested for IgE antibodies to these fruits by ImmunoCAP. ImmunoCAP inhibition assays with cedar and tomato extracts were performed on the 7 sera with adequate IgE antibodies to one or more of the fruits. The results of the inhibition experiments demonstrated a strong cross-reactivity between IgE antibodies to cedar pollen and the three fruits. The primary sensitization was to mountain cedar, since absorption with cedar pollen extract strongly inhibited reactivity to each of the fruits, but absorption with tomato extract did not significantly inhibit IgE binding to cedar extract. This is the first report of an OAS in mountain cedar pollinosis patients. Sensitivity to tomato, banana and apple should be considered in cedar-sensitive patients and confirmed if symptoms develop.
↩[28] - Peumans WJ, Proost P, Swennen RL, van Damme EJM. The abundant class III chitinase homolog in young developing banana fruits behaves as a transient vegetative storage protein and most probably serves as an important supply of amino acids for the synthesis of ripening-associated proteins. Plant Physiol 2002;130:1063-1072
AB: Analyses of the protein content and composition revealed dramatic changes in gene expression during in situ banana (Musa spp. [M. acuminata] cv. Grande Naine) fruit formation/ripening. The total banana protein content rapidly increased during the first 60 to 70 days, but remained constant for the rest of fruit formation/ripening. During the phase of rapid protein accumulation, an inactive homologue of class III chitinases accounted for up to 40% (w/v) of the total protein. Concomitant with the arrest of net protein accumulation, the chitinase-related protein (CRP) progressively decreased and several novel proteins appeared in the electropherograms. Hence, CRP behaved as a fruit-specific vegetative storage protein that accumulated during early fruit formation and served as a source of amino acids for the synthesis of ripening-associated proteins. Analyses of individual proteins revealed that a thaumatin-like protein, a beta-1,3-glucanase, a class I chitinase, and a mannose-binding lectin were the most abundant ripening-associated proteins. Because during the ripening of prematurely harvested bananas, similar changes transpired as in the in situ ripening bananas, CRP present in immature fruits was a sufficient source of amino acids for a quasi-normal synthesis of ripening-associated proteins. However, it is evident that the conversion of CRP in ripening-associated proteins took place at an accelerated rate, especially when climacteric ripening was induced by ethylene. The present report also includes a discussion of the accumulation of the major banana allergens and the identification of suitable promoters for the production of vaccines in transgenic bananas.
------------------------------------------------------- Koshte VL, Aalbers M, Calkhoven PG, Aalberse RC.
The potent IgG4-inducing antigen in banana is a mannose-binding lectin, BanLec-I Int Arch Allergy Immunol. 1992;97(1):17-24 IgG4 antibodies to banana were found to occur far more frequently than expected. The most important antigen involved proved to be a lectin, BanLec-I. Because of the lectin nature of the antigen, it was important to establish the antibody nature of the lectin-IgG4 interaction and to exclude an interaction between the sugar-binding site of the lectin and glycosidic chains on IgG4. Three arguments in support of immune binding are: (1) the binding of BanLec-I to IgG4 is mannoside resistant, whereas the binding to all other glycoproteins tested is mannoside inhibitable; (2) only a minor fraction of the IgG4 in serum and none of five IgG4 myelomas tested was bound, and (3) the lectin binds to the Fab fragment of the IgG4 molecule. A curious finding was that in the presence of high-molecular-weight glycoproteins the interaction between IgG4 and BanLec-I was enhanced by alpha-methyl mannoside. The probable explanation of this phenomenon is that complexes of the lectin with high-molecular-weight glycoproteins by sterical interference inhibit the interaction with human IgG4 antibodies (or with rabbit antibodies to the lectin). This inhibition is prevented in the presence of alpha-methyl mannoside. These results support the earlier suggestion that some lectins are particularly prone to induce an immune response upon oral feeding. This banana lectin might be a potentially useful carrier protein for oral antihapten immunization in humans.
↩[29] - Bobic S, Burazer L, Atanaskovic-Markovic M, Cirkovic Velickovic T, Jankov R, Gavrovic-Jankulovic M. Banana allergens and protein distribution in different banana cultivars. Allergy 2007;62(suppl. 83):339
Background: Banana fruit belongs to the Musaceae family and is extremely nutritious food, but also well known as an allergenic source, eliciting IgE-mediated reaction in sensitized individuals. Some banana proteins are proven to be allergens (profilin and class I chitinase) while the allergenic potential of other abundant proteins like thaumatin-like protein (TLP), ß-1,3-glucanase and banana lectin has not yet been well studied. Evaluation of allergenic potential of individual proteins should indicate relevant allergens for the component-resolved allergy diagnosis.
Methods: Banana extracts from five different bananas were made using the standard procedure and analyzed for protein content by SDS-PAGE, IEF and 2D electrophoresis. After electrophoresis proteins were electrotransfered or printed to the nitrocellulose membrane. They were then analyzed with polyclonal antiserum obtained by immunization of the rabbit with common banana extract, pooled sera from patients with positive skin-prick test to banana extract and polyclonal anti-chitinase antibodies. ELISA inhibition studies for five banana extracts were also performed using rabbit polyclonal antiserum and pooled patient's sera.
Results: Using polyclonal rabbit antiserum it was possible to detect all antigens from the common banana extract and also to compare the pattern of antigenicity between common banana and four banana cultivars analyzed in this study. Banana cultivars contain more or less the same protein profile, but there is a difference in the amount of proteins and isoforms thereof in the extracts. IgE antibodies from pooled patients sera were able to detect not only different isoforms of class I chitinase, but also ß-1,3-glucanase. The difference in the amount of TLP was detected by patients‚ IgE and rabbit polyclonal sera in the banana protein extracts.
Discussion: Rabbit polyclonal antiserum enabled us to analyze the presence and distribution of proteins and their isoforms in different banana cultivars. Results show that apart from the class I chitinase, which is known to be the major banana allergen, both ß-1,3-glucanase and TLP can bind IgE antibodies from patients allergic to banana. This result suggests that fruit extracts could be replaced by well defined panel of relevant allergenic isoforms to achieve more reliable diagnostic reagents for food allergy.
↩[30] - Sanchez-Monge R, Quirce S, Bobolea I, Pascual C, Diaz Perales A, Salcedo G. Identification of major banana allergens in pediatric patients. Allergy 2009;64(Suppl. 90):47
Background: Banana allergy is currently view as a class 2 food allergy, being latex and pollens the main sensitizing agents. Class I chitinases and profilin have been characterized as allergens responsible of these cross-reactions. However banana allergy is increasing in the paediatric population and its development seems to be, in some cases, independent of pollen sensitization. We ought to investigate the banana allergens implicated in paediatric banana allergy.
Methods: Thirty six children (range 6 months to 6 years of age) with clinical symptoms after the ingestion of banana were selected. Specific IgE to banana, other foods, several pollens and latex was measured by Pharmacia CAP System FEIA. IgE immunodetection of a banana protein extract using a serum pool and individual sera were performed. Main IgE binding proteins were purified by affinity, ion-exchange and HPLC chromatography and characterized by N-terminal sequencing and fingerprinting. Specific IgE of individual sera to the purified proteins was determinated by ELISA assays.
Results: Most of the selected banana allergic children were also sensitized to other foods and 50% of them showed pollinosis. None of them have allergy to latex, although some have latex positive CAP. Thaumatin, ß-1,3-glucanase and class III chitinase were detected as potentially relevant IgE-binding proteins from banana extract. Additionally, a non-specific lipid binding protein (LTP) and a superoxide dismutase were recognized by 20% of the sera.
Conclusions: Banana allergy in children can be a primary allergy independent of latex and pollen allergy. Several putative banana allergens seem to be plant defence proteins, such as thaumatins, glucanases and chitinases, with possible implications in latex and pollen cross-reactions.
↩[31] - Palomares O, Villalba M, Quiralte J, Polo F, Rodriguez R. 1,3-beta-glucanases as candidates in latex-pollen-vegetable food cross-reactivity. Clin Exp Allergy 2005;35:345-351
Summary Background 1,3-beta-glucanases (group 2 of pathogenesis-related proteins) are enzymes widely distributed among higher plants and have been recently proven to be significant allergens. Objective The aim of this work was to study the potential implication of 1,3-beta-glucanases in cross-reactivities among latex, pollen and vegetable foods. Methods The cDNA encoding the N-terminal domain (NtD) of Ole e 9, a major allergenic 1,3-beta-glucanase from olive pollen, was amplified by polymerase chain reaction and produced as a recombinant protein in Pichia pastoris (recombinant N-terminal domain, rNtD). Circular dichroism, ELISA, immunoblotting and immunoblotting inhibition experiments were carried out. Sera from olive pollen allergic patients and a rNtD-specific polyclonal antiserum were used. Results The NtD of Ole e 9 has been produced at high yield in the yeast P. pastoris and possesses 1,3-beta-glucanase activity. The expressed polypeptide conserves IgE and IgG immunodominant epitopes of the whole Ole e 9. A rNtD-specific polyclonal antiserum and sera from olive pollen allergic patients allowed detection of IgG and IgE reactive peptidic epitopes common to 1,3-beta-glucanase Ole e 9 in extracts from ash and birch pollen, tomato, potato, bell-pepper, banana and latex. Conclusion rNtD and homologous glucanases are new molecules to be used in diagnostic protocols as they could help to identify allergic pollen patients who are at risk for developing allergic symptoms to fruits, vegetables and latex.
↩[32] - Peumans WJ, Barre A, Derycke V, Rougé P, Zhang W, May GD, et al. Purification, characterization and structural analysis of an abundant beta-1,3-glucanase from banana fruit. Eur J Biochem 2000;267:1188-1195 ↩
[33] - Barre A, Culerrier R, Granier C, Selman L, Peumans WJ, Van Damme EJ et al. Mapping of IgE-binding epitopes on the major latex allergen Hev b 2 and the cross-reacting 1,3beta-glucanase fruit allergens as a molecular basis for the latex-fruit syndrome. Mol Immunol 2009;46:1595-1604
Nine distinct IgE-binding epitopes were identified along the entire amino acid sequence of the major latex allergen Hev b 2 (1,3beta-glucanase) using a set of synthetic 15-mer peptides frameshifted by 3 residues immobilized on cellulose membrane (Spot technique). Most of the amino acid residues building these IgE-binding epitopic regions are nicely exposed on the surface and the epitopes usually correspond to charged regions on the molecular surface of the protein. A smaller number of 5 IgE-binding epitopic areas was identified on the banana 1,3beta-glucanase, which exhibits a very similar overall conformation and charge distribution. The latter epitopes might be responsible for the IgE-binding cross-reactivity currently observed in the latex-fruit syndrome. Using rabbit polyclonal IgG anti-BanGluc as a probe instead of IgE from allergic patients the same epitopic regions were identified in both Hev b 2 and BanGluc. Additionally, surface-exposed regions with a very close conformation were predicted to occur on Ole e 9, the 1,3beta-glucanase allergen identified in olive pollen.
↩[34] - Peumans WJ, Zhang W, Barre A, Houles Astoul C, Balint-Kurti PJ, Rovira P, et al. Fruit-specific lectins from banana and plantain. Planta 2000;211:546-554
One of the predominant proteins in the pulp of ripe bananas (Musa acuminata L.) and plantains (Musa spp.) has been identified as a lectin.
The banana and plantain agglutinins (called BanLec and PlanLec, respectively) were purified in reasonable quantities using a novel isolation procedure, which prevented adsorption of the lectins onto insoluble endogenous polysaccharides. Both BanLec and PlanLec are dimeric proteins composed of two identical subunits of 15 kDa. They readily agglutinate rabbit erythrocytes and exhibit specificity towards mannose.
Molecular cloning revealed that BanLec has sequence similarity to previously described lectins of the family of jacalin-related lectins, and according to molecular modelling studies has the same overall fold and three-dimensional structure. The identification of BanLec and PlanLec demonstrates the occurrence of jacalin-related lectins in monocot species, suggesting that these lectins are more widespread among higher plants than is actually believed. The banana and plantain lectins are also the first documented examples of jacalin-related lectins, which are abundantly present in the pulp of mature fruits but are apparently absent from other tissues. However, after treatment of intact plants with methyl jasmonate, BanLec is also clearly induced in leaves. The banana lectin is a powerful murine T-cell mitogen. The relevance of the mitogenicity of the banana lectin is discussed in terms of both the physiological role of the lectin and the impact on food safety.
↩[35] - Gavrovic-Jankulovic M, Poulsen K, Cirkovic Velickovic T, Petersen A, Jankov R. Biochemical characterization of pepsin-resistant banana allergen. EAACI 23th Congress, Amsterdam, 12-16 June, 2004, Poster n°989
Background. Banana allergy, usually in association with hypersensitivity to other fruits and to latex, has been widely reported in the Mediterranean area. Resistance to proteolytic enzymes of the gastrointestinal tract is considered to be an important prerequisite determining the allergenicity of food proteins. The aim of this work was to identify and to characterize a novel pepsin-resistant banana allergen.
Methods. Pepsin-resistant protein in banana extract exposed for one hour to simulated gastric fluid (SGF, US Pharmacopoeia) was identified by reversed phase chromatography (mRPC C2/C18, Amersham) and SDS-PAGE. For further biochemical characterization protein was isolated by an ion-exchange chromatography. First strand cDNA synthesis from total RNA and PCR amplification were carried out using First-Strand cDNA Synthesis Kit (Amersham). Purified PCR products were cloned into the vector pCR2.1-TOPO and transformed into E. coli. Three distinct clones were sequenced. Beside digestion in SGF, isolated protein was exposed to the conditions of simulated intestinal fluid (SIF; 2 hours, US Pharmacopoeia) and cathepsin D. Preservation of IgE binding epitopes after the proteolytic enzymes treatment was assessed by Western blot analysis, using a pooled serum from 5 patients with latex-fruit syndrome.
Results. A 15 kDa pepsin-resistant protein from banana fruit reacted with sera from patients with latex-fruit syndrome. Degenerate primer deduced from the N-terminal sequence was used in cDNA synthesis from total RNA isolated from a green banana. The obtained cDNA sequence corresponded to a previously published cDNA from banana (GenBank Acc. No. AF001527). The protein belongs to pfam01419 that contains a jacalin-like lectin domain. Besides resistance to the environment of SGF, banana lectin was also stable to proteolysis in the conditions of the SIF as well as lysosomal protease cathepsin D. Banana lectin preserves the IgE binding ability after all enzymatic treatments.
Conclusion. The banana lectin described belongs to the family of proteins that contain modular organization of one or more repeats of a jacalin-like sequence, which are implicated in plant defense against viruses, fungi, and insects. Banana lectin is a true food allergen due to its stability to the conditions simulating human gastrointestinal digestion. This structural feature may explain the earlier finding that banana lectin was the most important IgG4-inducing banana antigen.
↩[36] - Polovic N, Blanusa M, Gavrovic-Jankulovic M, Atanaskovic-Markovic M, Burazer L, Jankov R, et al. A matrix effect in pectin-rich fruits hampers digestion of allergen by pepsin in vivo and in vitro. Clin Exp Allergy 2007;37:764-771
Abstract Background It is a general belief that a food allergen should be stable to gastric digestion. Various acidic plant polysaccharides, including pectin, are ubiquitous in fruit matrixes and can form hydrogels under low-pH conditions. Objective The purpose of this study was to investigate the effect of hydrogel forming polysaccharide-rich fruit matrixes on in vivo gastric and in vitro pepsic digestion of fruit allergens. Methods Fruit extract proteins (kiwi, banana, apple and cherry) and a purified major kiwi allergen Act c 2 were digested with simulated gastric fluid in accordance with the US Pharmacopeia. In vivo experiments on kiwi fruit digestion were performed on four healthy non-atopic volunteers by examining the gastric content 1 h after ingestion of kiwi fruit. The Act c 2 and kiwi proteins were detected in immunoblots using monoclonal anti-Act c 2 antibodies and rabbit polyclonal antisera. Results Crude fruit extracts were resistant to digestion by pepsin when compared with commonly prepared extracts. In the gastric content of all volunteers, following kiwi fruit ingestion and immunoblotting, intact Act c 2 was detected with anti-Act c 2 monoclonal antibodies, while kiwi proteins of higher molecular weights were detected using rabbit polyclonal antisera. Addition of apple fruit pectin (1.5% and 3%) to the purified kiwi allergen was able to protect it from pepsin digestion in vitro. Conclusion The matrix effect in pectin-rich fruits can influence the digestibility of food proteins and thereby the process of allergic sensitization in atopic individuals.
↩[37] - Wellhausen A, Schöning B, Petersen A, Vieths S. IgE binding to a new cross-reactive structure: a 35 kDa protein in birch pollen, exotic fruit and other plant foods. Z Ernahrungswiss 1996;35:348-355
Food allergies in birch pollen allergic patients have been shown to be due to cross-reactivities of specific IgE antibodies which are directed against birch pollen allergens with related proteins in fruit, nuts and vegetables. We identified a new cross-reactive structure of 35 kDa in birch pollen and some plant food extracts by Enzyme Allergosorbent Test (EAST) and immunoblot inhibition studies. The 35 kDa birch pollen protein is a minor allergen to which approximately 10-15% of birch pollen allergic individuals have specific IgE. Our data demonstrate that there is cross-reactivity of this protein with proteins of comparable size from lychee, mango, banana, orange, apple, pear and carrot. While the 35 kDa protein is immunologically independent of the major birch pollen allergen Bet v 1, we also observed IgE binding to a 34 kDa structure which appears to be a Bet v 1 dimer.
↩[38] - Asero R. Plant Food Allergies: A Suggested Approach to Allergen-Resolved Diagnosis in the Clinical Practice by Identifying Easily Available Sensitization Markers. Int Arch Allergy Immunol 2005;138:1-11
"BACKGROUND: Molecular biology techniques have led to the identification of a number of allergens in vegetable foods, but due to the lack of purified food proteins for routine diagnostic use, the detection of sensitizing allergens remains a nearly impossible task in most clinical settings. The allergen-resolved diagnosis of food allergy is essential because each plant-derived food may contain a number of different allergens showing different physical/chemical characteristics that strongly influence the clinical expression of allergy; moreover, many allergens may cross-react with homologue proteins present in botanically unrelated vegetable foods .
OBJECTIVE: Through a review of the available literature, this study aimed to detect ""markers"" of sensitization to specific plant food allergens that are easily accessible in the clinical practice .
RESULTS: There are several ""markers"" of sensitization to different allergenic proteins in vegetable foods that can be helpful in the clinical practice. Specific algorithms for patients allergic to Rosaceae and to tree nuts were built .
CONCLUSION: Clinical allergologists lacking the assistance of an advanced molecular biology lab may take advantage of some specific clinical data as well as of some ""markers"" in the difficult task of correctly diagnosing patients with plant food allergy and to provide them the best preventive advice"
↩[39] - Lohani S, Trivedi PK, Nath P. Changes in activities of cell wall hydrolases during ethylene-induced ripening in banana: effect of 1-MCP, ABA and IAA. Postharvest Biol Technol 2004;31:119-126
Softening during ripening in climacteric fruit is generally attributed to degradation in cell wall assembly, particularly the solublization of pectin. These changes could involve increased activities of various cell wall hydrolases. Their activity is believed to be regulated by ripening-related hormones and/or other signal molecules. Activities of pectin methyl esterase (PME), polygalacturonase (PG), pectate lyase (PL) and cellulase in banana cv. dwarf cavendish fruit were measured over a period of 7 days after ripening was initiated with ethylene. Effects of treatments with 1-methylcyclopropene (1-MCP), abscisic acid (ABA) and indole acetic acid (IAA) on activities of these hydrolases were measured in order to help elucidate their roles during banana ripening. Ethylene stimulated activities of all four enzymes, at best differentially. 1-MCP and IAA suppressed the ethylene effects. ABA stimulated activities of all hydrolases except polygalacturonase. ABA stimulation was most evident for pectate lyase. Thus ethylene plays a major role in up-regulating the activities of various cell wall hydrolases. In contrast IAA suppresses their activity. ABA can enhance softening with or without ethylene.
↩[40] - Marin-Rodriguez MC, Smith DL, Manning K, Orchard J, Seymour GB. Pectate lyase gene expression and enzyme activity in ripening banana fruit. Plant Mol Biol 2003;51:851-857
Two distinct cDNA clones showing sequence homology to higher-plant pectate lyase (Pel) genes were isolated from ripening banana fruits. The transcripts were detected only in fruit tissue and both were strongly ripening-related. Yeast transformation with the most highly expressed Pel clone produced a recombinant protein with pectate lyase activity, demonstrating that this sequence was likely to encode a pectate lyase protein in planta. An assay developed for measuring the action of the endogenous enzyme from banana pulp tissue revealed a significant increase in calcium-dependent pectate lyase activity during ripening. The enhanced levels of enzyme activity corresponded with an increase in soluble polyuronides from banana pulp.
↩[41] - Clendennen SK, May CD. Differential Gene Expression in Ripening Banana Fruit. Plant Physiol 1997;115:463-469
During banana (Musa acuminata L.) fruit ripening ethylene production triggers a developmental cascade that is accompanied by a massive conversion of starch to sugars, an associated burst of respiratory activity, and an increase in protein synthesis. Differential screening of cDNA libraries representing banana pulp at ripening stages 1 and 3 has led to the isolation of 11 nonredundant groups of differentially expressed mRNAs. Identification of these transcripts by partial sequence analysis indicates that two of the mRNAs encode proteins involved in carbohydrate metabolism, whereas others encode proteins thought to be associated with pathogenesis, senescence, or stress responses in plants. Their relative abundance in the pulp and tissue-specific distribution in greenhouse-grown banana plants were determined by northern-blot analyses. The relative abundance of transcripts encoding starch synthase, granule-bound starch synthase, chitinase, lectin, and a type-2 metallothionein decreased in pulp during ripening. Transcripts encoding endochitinase, beta-1,3-glucanase, a thaumatin-like protein, ascorbate peroxidase, metallothionein, and a putative senescence-related protein increased early in ripening. The elucidation of the molecular events associated with banana ripening will facilitate a better understanding and control of these processes, and will allow us to attain our long-term goal of producing candidate oral vaccines in transgenic banana plants.
↩[42] - Wilson IBH, Zeleny R, Kolarich D, Staudacher E, Stroop CJM, Kamerling JP, et al. Analysis of Asn-linked glycans from vegetable foodstuffs: widespread occurrence of Lewis a, core alpha-1,3-linked fucose and xylose substitutions. Glycobiology 2001;11:261-274
The N-glycans from 27 "plant" foodstuffs, including one from a gymnospermic plant and one from a fungus, were prepared by a new procedure and examined by means of matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF-MS). For several samples, glycan structures were additionally investigated by size-fractionation and reverse-phase high-performance liquid chromatography in conjunction with exoglycosidase digests and finally also (1)H-nuclear magnetic resonance spectroscopy. The glycans found ranged from the typical vacuolar "horseradish peroxidase" type and oligomannose to complex Le(a)-carrying structures. Though the common mushroom exclusively contained N-glycans of the oligomannosidic type, all plant foods contained mixtures of the above-mentioned types. Apple, asparagus, avocado, banana, carrot, celery, hazelnut, kiwi, onion, orange, pear, pignoli, strawberry, and walnut were particularly rich in Le(a)-carrying N-glycans. Although traces of Le(a)-containing structures were also present in almond, pistachio, potato, and tomato, no such glycans could be found in cauliflower. Coconut exhibited almost exclusively N-glycans containing only xylose but no fucose. Oligomannosidic N-glycans dominated in buckwheat and especially in the legume seeds mung bean, pea, peanut, and soybean. Papaya presented a unique set of hybrid type structures partially containing the Le(a) determinant. These results are not only compatible with the hypothesis that the carbohydrate structures are another potential source of immunological cross-reaction between different plant allergens, but they also demonstrate that the Le(a)-type structure is very widespread among plants.
↩[43] - Paschinger K, Fabini G, Schuster D, Rendic D, Wilson IB. Definition of immunogenic carbohydrate epitopes. Acta Biochim Pol 2005;52:629-632
Carbohydrates are known as sources of immunological cross-reactivity of allergenic significance. In celery and in cypress pollen, the major allergens Api g 5 and Cup a 1 are recognised by antisera raised against anti-horseradish peroxidase and by patients' IgE which apparently bind carbohydrate epitopes; mass spectrometric analysis of the tryptic peptides and of their N-glycans showed the presence of oligosaccharides carrying both xylose and core alpha1,3-fucose residues. Core alpha1,3-fucose residues are also a feature of invertebrates: genetic and biochemical studies on the fruitfly Drosophila melanogaster, the parasitic trematode Schistosoma mansoni and the nematode worm Caenorhabditis elegans indicate that these organisms possess core alpha1,3-fucosyltransferases. Various experiments have shown that fucosyltransferases from both fly and worm are responsible in vivo and in vitro for the synthesis of N-glycans which cross-react with anti-horseradish peroxidase; thus, we can consider these enzymes as useful tools in generating standard compounds for testing cross-reactive carbohydrate epitopes of allergenic interest
↩[44] - 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
Imprimer la bibliographieBACKGROUND: 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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