- reagin
- 1. Wolff-Eisner term for antibody. 2. Old term for the “Wassermann” antibody; not to be confused with the Prausnitz-Küstner antibody. 3. Antibodies that mediate immediate hypersensitivity reactions (IgE in humans). 4. SYN: homocytotropic antibody.- atopic r. SYN: Prausnitz-Küstner antibody.
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re·agin rē-'ā-jən, -gən n1) a substance that is in the blood of individuals with syphilis and is responsible for positive serological reactions for syphilis2) an antibody (as IgE in humans) that mediates hypersensitive allergic reactions of rapid onsetre·agin·ic .rē-ə-'jin-ik, -'gin- adj* * *
n.a type of antibody, formed against an allergen, that has special affinity for cell membranes and remains fixed in various tissues. Subsequent contact with the allergen causes damage to the tissues when the antigen-antibody reaction occurs. The damaged cells, particularly mast cell, release histamine and serotonin, which are responsible for the local inflammation of an allergy or the very severe effects of anaphylactic shock (see anaphylaxis). Reagins belong to the IgE class of immunoglobulin.* * *
re·a·gin (reґə-jin) [reagent + -in] 1. the antibody that mediates type I hypersensitivity reactions; in humans, IgE. 2. former name for the serum antibody detected by the Wassermann test.
Medical dictionary. 2011.