secretory immunoglobulin A

immunoglobulin /im·mu·no·glob·u·lin/ (-glob´ūl-in) a protein of animal origin with known antibody activity, synthesized by lymphocytes and plasma cells and found in serum and in other body fluids and tissues; abbreviated Ig. There are five distinct classes based on structural and antigenic properties: IgA, IgD, IgE, IgG, and IgM.

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secretory immunoglobulin A  IgA immunoglobulin in which two IgA molecules are linked by a polypeptide (secretory piece) and by a J chain; it is the predominant immunoglobulin.

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secretory immunoglobulin A,

n protein found in bodily secretions; can protect against antigen overload by binding the antigens and transporting them through the liver into the bile to be eliminated. In some cases it can prevent the absorption of antigens.