What is allergen cross-reactivity?
Cross reactivity occurs when allergens from one species cause allergic reactions in a patient who was sensitized to a different species. For example, a person who has developed sensitivity to pollen from live oak in California may experience symptoms from white oak pollen in Connecticut.Cross reactivity results when two or more different proteins bind to the same IgE antibodies because of similarities in the structure of the IgE binding site, or epitope, on the proteins. Cross-reacting allergens are usually taxonomically similar and have similar amino acid sequences. Cross reactivity between allergens can be suggested by correlation with clinical history and experience or immunoblotting with patient sera or monoclonal antibodies. For example; patients allergic to short ragweed may get itching in the mouth when they eat melons, a high percentage of patients that are allergic to birch also have IgE antibody to apple, and patients that are allergic to yellow jacket venom will show IgE bin