Comparison of intrinsic allergenicity potentials of gliadins from durum and soft white wheats in an adjuvant-free mouse model

Abstract

Abstract Wheat is one of the major allergenic foods capable of eliciting life-threatening anaphylaxis. Discovering potential hypo/hyper-allergenic wheat classes is imperative to advance our knowledge and manage wheat allergy. Durum wheat (genome AABB) and soft white wheat (genome AABBDD) are two commonly consumed wheats. However, whether there are differences in the intrinsic allergenicity potential between them is unknown. Here, we tested the hypothesis that gliadins extracted from durum and soft white wheats will differ in their intrinsic allergenicity in an adjuvant-free mouse model that uses skin sensitization followed by intraperitoneal (IP) allergen challenge. Balb/c female mice were produced and maintained on a plant protein-free diet during this study. Groups of mice (n=5–10/group) were exposed to gliadins or vehicle via the skin once a week for 9 weeks. IgE responses were analyzed by ELISA to determine sensitization. Systemic anaphylaxis upon IP challenge was quantified by hypothermic shock response (HSR); mucosal mast cell response (MMCR) was quantified by measuring MMCP-1 in the blood. Our results suggest that mice exhibited robust, but comparable levels of specific IgE antibody responses after skin exposures to both wheat gliadins elicited. HSRs induced upon IP challenges with gliadins from the two wheats displayed strikingly similar kinetics. Interestingly, soft white wheat gliadin was significantly more potent in eliciting MMCR compared to the durum wheat gliadin. We demonstrate for the first-time the similarities and differences in intrinsic allergenicity potentials of gliadins obtained from the two wheats. Supported by grants from USDA/NIFA Hatch Project MICL02486 (Accession Number: 1012322)