Allergy and Clinical Immunology

The systemic manifestations induced by food hypersensitivity responses are due to the ability of localized exposure to foods in the gastrointestinal tract to result in symptoms in distal target organs. Cow’s milk protein, for example, may induce hives (urticaria), atopic dermatitis, isolated gastrointestinal symptoms or severe generalized anaphylaxis in different individuals or in the same person at different times. These diverse manifestations are the result of complex interactions among the causal food protein, gut, immune system and target organs. The dynamic state of these interactions is demonstrated by

the development of food tolerance in most subjects and by the ability to experience the development of new allergies in some subjects. This presentation explores the variety of clinical manifestations of food hypersensitivity disorders in the context of the question: What determines the local or systemic expression of food allergy in a given individual at a particular time? Evidence is provided for both systemic and local immune activation. The role of food-protein chemistry, absorption and processing of ingested allergen, immune responses (type, degree, and specificity) and target organ hyper reactivity are considered as determinants in the expression of food allergic disorders.