A structural basis for food allergy: The role of cross-reactivity

PURPOSE OF REVIEW: Immunologic cross-reactivity, which is important in many aspects of host defense and immune-mediated diseases, is a prominent feature of allergic disorders. The goal of this article is to define allergenic cross-reactivity and its role in food allergy, review current understanding of mechanisms of cross-reactivity, and consider how advances in our ability to predict cross-reactivity can impact diagnosis and treatment of food allergy. RECENT FINDINGS: Recent evidence suggests that specific T cells, in addition to IgE, developed in response to inhaled allergens can cross-react with related food allergens, leading to distinct clinical reactions. Several new cross-reactivities have been identified, including food-food, pollen-food, and latex-venom associations. Debate continues regarding prediction of allergenicity based on protein structure, and clinical relevance of in-vitro testing. Cross-reactivity is also being used to develop specific immunotherapy for treatment of food allergy. SUMMARY: A thorough understanding of immunologic cross-reactivity is essential to advancing our knowledge about food allergy. This knowledge will help elucidate the pathogenesis of the disorder and prevent exposures to allergenic, genetically engineered foods. New insight will allow for better utilization of current diagnostic tools and the development of more accurate tests and therapies for food allergy.