Cross-reactive epitopes and their role in food allergy

J Allergy Clin Immunol. 2023 May;151(5):1178-1190. doi: 10.1016/j.jaci.2022.12.827. Epub 2023 Mar 15.


Allergenic cross-reactivity among food allergens complicates the diagnosis and management of food allergy. This can result in many patients being sensitized (having allergen-specific IgE) to foods without exhibiting clinical reactivity. Some food groups such as shellfish, fish, tree nuts, and peanuts have very high rates of cross-reactivity. In contrast, relatively low rates are noted for grains and milk, whereas many other food families have variable rates of cross-reactivity or are not well studied. Although classical cross-reactive carbohydrate determinants are clinically not relevant, α-Gal in red meat through tick bites can lead to severe reactions. Multiple sensitizations to tree nuts complicate the diagnosis and management of patients allergic to peanut and tree nut. This review discusses cross-reactive allergens and cross-reactive carbohydrate determinants in the major food groups, and where available, describes their B-cell and T-cell epitopes. The clinical relevance of these cross-reactive B-cell and T-cell epitopes is highlighted and their possible impact on allergen-specific immunotherapy for food allergy is discussed.

Keywords: Allergens; B-cell; IgE antibody; T-cell; allergenic cross-reactivity; clinical cross-reactivity; cross-reactive IgE; cross-reactive epitope; food allergy; tropomyosin.

Publication types

  • Review
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Allergens
  • Animals
  • Cross Reactions
  • Epitopes, T-Lymphocyte*
  • Food Hypersensitivity* / diagnosis
  • Food Hypersensitivity* / therapy
  • Immunoglobulin E
  • Nuts


  • Epitopes, T-Lymphocyte
  • Allergens
  • Immunoglobulin E