Immune response and clinical reaction to food proteins with high vs. low/non allergenic potential in an adjuvant-free mouse model (79.17)

Abstract

Abstract Predicting allergenic potential of novel proteins present in foods such as genetically modified foods is a major challenge facing regulatory agencies and biotech industries. Here we tested the hypothesis that the adjuvant-free mouse model that we have previously reported (Birmingham et al Int Arch Allergy Immunol 2007;144(3):203-10) will be useful to distinguish human food proteins with high vs. low/non allergenic potential. Three readouts were used for testing food allergenicity: 1) systemic specific IgE antibody response to transdermal food protein exposure; 2) clinical symptoms of systemic anaphylaxis to oral food protein challenge; and 3) drop in rectal temperature (hypothermia) to oral food protein challenge. The following food proteins were tested for allergenicity: food proteins with high allergenic potential (cashew nut, milk), food proteins with low/non allergenic potential (kidney bean, Pinto bean); and a food protein with unknown history of allergenicity (Amaranth seed protein). We found that whereas, both cashew nut and milk tested positive for all three readouts of allergenicity, Pinto bean and kidney bean although induced specific IgE antibodies, did not cause systemic anaphylaxis and hypothermia. Interestingly, Amaranth seed protein induced not only a robust IgE response but also elicited clinical symptoms of systemic anaphylaxis as well as hypothermia. These data demonstrate that: 1) further testing with additional food proteins is necessary to evaluate the predictive utility of this mouse model for allergenicity testing; and 2) further studies are needed to evaluate the relationship between circulating food specific IgE antibodies and clinical sensitization for oral food induced systemic anaphylaxis. Funding: US EPA STAR Grant#R833133