Ige Cross-Reactivity Between Shellfish and Diverse Potential Food Insects

Is observed IgE cross-reactivity of insect and shellfish tropomyosins explained by sequence and/or structural characteristics and if so can we use this to predict likely reactivity? We analyzed cross-reactivity patterns of shellfish and seven insect species using sera from 14 shellfish allergic individuals using IgE immunoblotting. We obtained protein sequences either from public databases (where available) or from translation of novel insect tropomyosin genes cloned in our lab. Relevence of both existing and novel tropomyosin sequences was demonstrated by quantitative protein mass spectrometry. Distinct patterns of cross-reactivity were observed, with three edible insect species consistently displaying lower binding of IgE. This pattern was not due to overall sequence homology. These results will be discussed with reference to differences in localized protein sequence motifs and other phyisco-chemical protein properties. Edible insects vary in the capacity of major allergens to bind shrimp allergic IgE, and therefore potentially elicit allergic reactions. This information is essential for the successful risk assessment of edible insects as potential food allergens.