Pathophysiology of food allergy.

In this article we review the pathophysiology of food allergy, which affects 4% of US children and 2% of adults, and is increasing in prevalence. Most food allergens share certain specific physicochemical characteristics that allow them to resist digestion, thus enhancing allergenicity. During allergic sensitization, these allergens are encountered by specialized dendritic cell populations in the gut, which leads to T-cell priming and the production of allergen-specific IgE production by B cells. Tissue-resident mast cells then bind IgE, and allergic reactions are elicited when mast cells are reexposed to allergen. Adjacent IgE molecules bound to the surface of the mast cell become cross-linked, causing mast cell degranulation and release of powerful vasoactive compounds that cause allergic symptoms.