Identification of cross-reactive B-cell epitopes between Bos d 9.0101(Bos Taurus) and Gly m 5.0101 (Glycine max) by epitope mapping MALDI-TOF MS

CANDREVA ANGELA; FERRER-NAVARRO MARIO; BRONSOMS SILVIA; QUIROGA ALEJANDRA; CURCIARELLO RENATA; ANA CAUERHFF; PETRUCCELLI SILVANA; DOCENA GUILLERMO; TREJO SEBASTIAN

JOURNAL OF PROTEOMICS

ELSEVIER SCIENCE BV

Lugar: Amsterdam; Año: 2017

1874-3919

Exposure to cow´s milk and soy proteins constitutes one of the most common causes of food allergy and cross-allergenicity in a restricted proportion of milk allergic pediatric patients treated with soy formulae as a dairy substitute. We have previously identified several cross-reactive allergens between milk and soy that may explain this intolerance., The purpose of the present work was to investigate cross-reactive epitopes applying two different approaches for epitope mapping, using an α-casein-specific monoclonal antibody (1D5 mAb), purified milk caseins, and the recombinant soy allergen Gly m 5.0101(Glym5). The 1D5 mAb was immobilized onto magnetic beads, incubated with the peptide mixture previously obtained by enzymatic digestion of the allergens, and the captured peptides were identified by MALDI-TOF MS analysis. On a second approach, the peptide mixture was resolved by RP-HPLC and immunodominant peptides were identified by dot blot with the mAb. Finally, the peptides identified by both strategies were sequenced by MALDI-TOF mass spectrometry.This novel MS based approach led us to identify and characterize four peptides on α-casein and three peptides on Glym5 with a common core motif. Information obtained from these cross-reactive epitopes allows us to gain valuable insight into the molecular mechanisms of cross-reactivity, to further develop new and more effective vaccines for food allergy.