secretory immunoglobulin A
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se·cre·to·ry im·mu·no·glob·u·lin A
a subclass of IgA that is found primarily in secretions such as tears and colostrum. This form of IgA is protected from proteolytic degradation by the presence of a secretory component.
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.