title: Immune responses to environmental antigens absorbed through the gastrointestinal tract.
abstract: Foods, food additives, beverages, drugs, and intestinal microorganisms are potentially important sources of environmental antigens. While proteins taken orally ordinarily are absorbed to only a limited extent, under appropriate circumstances enough absorption occurs to produce an immune response. Acute allergic reactions to foods are not uncommon and as a rule are mediated by IgE antibodies. The possibility that small quantities of food antigens absorbed over a period of years without acute symptoms of allergy might produce a cumulative systemic or local immunological toxicity remains to be convincingly demonstrated.
mesh_terms: D000367:Age Factors; D000818:Animals; D004342:Drug Hypersensitivity / Q000276:immunology; D004705:Endocytosis; D000939:Epitopes; D000431:Ethanol / Q000276:immunology; D005399:Fishes / Q000276:immunology*; D005503:Food Additives; D005512:Food Hypersensitivity / Q000276:immunology*; D006801:Humans; D007111:Immunity, Cellular; D007116:Immunization, Passive; D007071:Immunoglobulin A, Secretory / Q000502:physiology; D007073:Immunoglobulin E / Q000378:metabolism; D007408:Intestinal Absorption; D007782:Lactoglobulins / Q000276:immunology*; D008222:Lymphokines / Q000502:physiology; D008970:Molecular Weight; D009124:Muscle Proteins / Q000276:immunology; D011506:Proteins / Q000276:immunology / Q000378:metabolism
chemical_list: D000939:Epitopes; D005503:Food Additives; D007071:Immunoglobulin A, Secretory; D007782:Lactoglobulins; D008222:Lymphokines; D009124:Muscle Proteins; D011506:Proteins; D007073:Immunoglobulin E; D000431:Ethanol