BACKGROUND: Ara h 1, a vicilin; Ara h 2, a 2S albumin; and Ara h 3, a legumin, are major peanut allergens. Ara h 2 is an important predictor of clinical reactivity to peanut, but cosensitization to all 3 allergens is correlated with the severity of patients' symptoms. OBJECTIVE: We investigated whether cosensitization to these 3 allergens is caused by IgE cross-reactivity, despite the fact that they do not display obvious structural or sequence similarities. METHODS: IgE cross-inhibitions were performed with purified Ara h 1, Ara h 2, and Ara h 3 and IgG-depleted sera from 10 patients with peanut allergy. After an in silico search for similar peptides, IgE ELISA inhibition assays with synthetic peptides were performed. RESULTS: Ara h 2 inhibited IgE binding to Ara h 1 (average, 86% ± 13%) and Ara h 3 (average, 96% ± 6%). IgE binding to Ara h 2 was inhibited by Ara h 1 by 78% ± 15% and by Ara h 3 by 80% ± 6%. A subsequent sequence comparison showed that these nonhomologous allergens contained several similar surface-exposed peptides. IgE binding to Ara h 2-derived peptides was completely inhibited by Ara h 1 and Ara h 3. A mixture of these peptides reduced IgE binding to Ara h 1 and Ara h 3 by 20% to 60% and to Ara h 2 by 49% to 89%. CONCLUSION: Occurrence of similar sequences in the 3 major peanut allergens accounts for the high extent of cross-reactivity among them.
BACKGROUND:Ara h 1, a vicilin; Ara h 2, a 2S albumin; and Ara h 3, a legumin, are major peanut allergens. Ara h 2 is an important predictor of clinical reactivity to peanut, but cosensitization to all 3 allergens is correlated with the severity of patients' symptoms. OBJECTIVE: We investigated whether cosensitization to these 3 allergens is caused by IgE cross-reactivity, despite the fact that they do not display obvious structural or sequence similarities. METHODS: IgE cross-inhibitions were performed with purified Ara h 1, Ara h 2, and Ara h 3 and IgG-depleted sera from 10 patients with peanutallergy. After an in silico search for similar peptides, IgE ELISA inhibition assays with synthetic peptides were performed. RESULTS:Ara h 2 inhibited IgE binding to Ara h 1 (average, 86% ± 13%) and Ara h 3 (average, 96% ± 6%). IgE binding to Ara h 2 was inhibited by Ara h 1 by 78% ± 15% and by Ara h 3 by 80% ± 6%. A subsequent sequence comparison showed that these nonhomologous allergens contained several similar surface-exposed peptides. IgE binding to Ara h 2-derived peptides was completely inhibited by Ara h 1 and Ara h 3. A mixture of these peptides reduced IgE binding to Ara h 1 and Ara h 3 by 20% to 60% and to Ara h 2 by 49% to 89%. CONCLUSION: Occurrence of similar sequences in the 3 major peanut allergens accounts for the high extent of cross-reactivity among them.
Authors: Peter E Deak; Baksun Kim; Amina Abdul Qayum; Jaeho Shin; Girish Vitalpur; Kirsten M Kloepfer; Matthew J Turner; Neal Smith; Wayne G Shreffler; Tanyel Kiziltepe; Mark H Kaplan; Basar Bilgicer Journal: Proc Natl Acad Sci U S A Date: 2019-04-08 Impact factor: 11.205
Authors: Wenzhe Lu; Surendra S Negi; Catherine H Schein; Soheila J Maleki; Barry K Hurlburt; Werner Braun Journal: Mol Immunol Date: 2018-04-06 Impact factor: 4.407
Authors: Anna Pomés; Maksymilian Chruszcz; Alla Gustchina; Wladek Minor; Geoffrey A Mueller; Lars C Pedersen; Alexander Wlodawer; Martin D Chapman Journal: J Allergy Clin Immunol Date: 2015-07 Impact factor: 10.793
Authors: Jelena P Berglund; Nicole Szczepanski; Anusha Penumarti; Ayeshia Beavers; Janelle Kesselring; Kelly Orgel; Bruce Burnett; A Wesley Burks; Michael Kulis Journal: J Allergy Clin Immunol Pract Date: 2017-01-26
Authors: Kelly A Orgel; Shiteng Duan; Benjamin L Wright; Soheila J Maleki; John C Wolf; Brian P Vickery; A Wesley Burks; James C Paulson; Mike D Kulis; Matthew S Macauley Journal: J Allergy Clin Immunol Date: 2016-08-20 Impact factor: 10.793