Analysis of transdermal sensitization and oral anaphylaxis using salt-soluble protein extracts from diploid wheats in an adjuvant-free mouse model

Abstract

Abstract Wheat allergies are growing at an alarming rate for reasons that are not well understood. The commonly consumed wheats belong to the AABB and AABBDD genotypes. The AA wheat is less commonly consumed, and the DD wheat is not commercially available. It is unknown at present whether the diploid wheats elicit allergic reactions in mice. Here we tested the hypothesis that the salt-soluble protein extracts (SSPEs) from AA and DD wheats will induce food allergy in Balb/cJ male mice in an adjuvant-free model. We grew the DD wheat at our university and used it in this study. The AA wheat was obtained from www.einkorn.com. Balb/cJ male mice were bred and maintained on a plant protein-free diet. Mice were exposed to SSPEs or saline via skin once a week for nine weeks. SSPE-specific IgE (sIgE) was measured using an ELISA. After sensitization, mice were orally challenged with SSPEs or saline to elicit a hypothermia shock response (HSR). We found that both AA- and DD-SSPEs elicited significant and comparable levels of sIgE responses upon skin exposures. Oral challenge with DD-SSPE but not saline in DD-SSPE sensitized elicited a mild HSR lasting up to only 15 minutes. In contrast, oral challenge with AA-SSPE but not saline in AA-SSPE sensitized mice elicited a severe HSR lasting for 30 minutes. These data together suggest that the diploid wheats induce comparable sensitization, but DD wheat is less potent in inducing oral anaphylaxis compared to the AA wheat.