Evaluation of salt-soluble protein extract from an ancient wheat progenitor (Aegilops tauschii) for intrinsic allergenicity in an adjuvant-free mouse model of wheat allergy

Abstract

Abstract Wheat allergies are a growing significant health concern around the globe. The ancient diploid wheat progenitor, Aegilops tauschii (genome DD), contributed to the genetic diversity of the common soft white wheat (Triticum aestivum, genomes AABBDD). The allergenic potential of Ae. tauschii is largely unknown. Here we tested the hypothesis that the the salt-soluble protein extract (SSPE) from Ae. tauschii will be intrinsically allergenic in an adjuvant-free mouse model of wheat allergy. The ancient wheat progenitor was grown at the Michigan State University greenhouse using the seeds stored at our wheat breeding program. The SSPE was prepared, characterized for quality, and then tested in the mouse model that uses skin sensitization followed by oral allergen challenge. Balb/c mice were produced and maintained on a plant protein-free diet. Groups of adult mice (n=10/group) were repeatedly exposed to SSPE or vehicle via the skin. Allergic sensitization was assessed by specific IgE (sIgE) response. Oral anaphylaxis was quantified by hypothermic shock response (HSR). The mucosal mast cell response (MMCR) was quantified by measuring MMCP-1 in the blood. Repeated skin exposure to SSPE but not the vehicle elicited robust sIgE response. Oral SSPE challenge but not vehicle challenge elicited significant, but a modest HSR as well as MMCR. In summary, we report the characterization of intrinsic allergenicity potential of the SSPE obtained from the Ae. tauschii wheat progenitor for the first time. Funding: USDA/NIFA. The United States Department of Agriculture (USDA)/National Institute of Food and Agriculture (NIFA); Hatch project MICL02486 (Accession Number: 1012322); Hatch project MICL01699; Agricultural and Food Research Initiative Competitive Program, grant number: 2018-67017-27876