reagin

biochemistry

Also known as: Prausnitz-Küstner antibody, homocytotropic antibody

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Also called:: homocytotropic antibody or prausnitz-küstner antibody

Related Topics:: antibody; allergy

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reagin, type of antibody found in the serum and skin of allergically hypersensitive persons and in smaller amounts in the serum of normally sensitive persons. Most reaginic antibodies are the immunoglobulin E (IgE) fraction in the blood. Reagins are easily destroyed by heating, do not pass the placental barrier (i.e., an allergic mother cannot passively make her child allergic), and have a much longer life span than other types of antibodies. Reaginic antibodies can be transferred passively to a second person; thus, blood transfusions from allergic donors have occasionally produced temporary identical allergies in the nonallergic recipient for a brief time. See also allergy; atopy.

The Editors of Encyclopaedia BritannicaThis article was most recently revised and updated by Kara Rogers.