Poly-Ig Receptor: Specialized Fc receptors (RECEPTORS, FC) for polymeric immunoglobulins, which mediate transcytosis of polymeric IMMUNOGLOBULIN A and IMMUNOGLOBULIN M into external secretions. They are found on the surfaces of epithelial cells and hepatocytes. After binding to IMMUNOGLOBULIN A, the receptor-ligand complex undergoes endocytosis, transport by vesicle, and secretion into the lumen by exocytosis. Before release, the part of the receptor (SECRETORY COMPONENT) that is bound to IMMUNOGLOBULIN A is proteolytically cleaved from its transmembrane tail. (From Rosen et al., The Dictionary of Immunology, 1989)

Synonym: polymeric immunoglobulin receptor, polymeric ig receptor, polyimmunoglobulin receptor.

Terms Related to Poly-Ig Receptor

• Secretory Component

  A glycoprotein found in a variety of external secretions (tears, bile, colostrum) usually complexed to secreted polymeric immunoglobulins (IMMUNOGLOBULIN A or, less frequently IMMUNOGLOBULIN M). ...

• J Chain Immunoglobulins

  The immunoglobulin fragments found in the light chain fractions of secretory IMMUNOGLOBULIN A and polymeric IMMUNOGLOBULIN M in a ratio of one J chain per ...

• Immunoglobulin A

  Represents 15-20% of the human serum immunoglobulins, mostly as the 4-chain polymer in humans or dimer in other mammals. Secretory IgA (IMMUNOGLOBULIN A, SECRETORY) ...

• Secretory Immunoglobulin A

  The principle immunoglobulin in exocrine secretions such as milk, respiratory and intestinal mucin, saliva and tears. The complete molecule (around 400 kD) is composed of ...

• Immunoglobulins

  Glycoproteins present in the blood (ANTIBODIES) and in other tissue. They are classified by structure and activity into five classes (IMMUNOGLOBULIN A; IMMUNOGLOBULIN D; IMMUNOGLOBULIN ...

• IgA

  Represents 15-20% of the human serum immunoglobulins, mostly as the 4-chain polymer in humans or dimer in other mammals. Secretory IgA (IMMUNOGLOBULIN A, SECRETORY) ...

• Secretory IgA

  The principle immunoglobulin in exocrine secretions such as milk, respiratory and intestinal mucin, saliva and tears. The complete molecule (around 400 kD) is composed of ...

• IgA2

  Represents 15-20% of the human serum immunoglobulins, mostly as the 4-chain polymer in humans or dimer in other mammals. Secretory IgA (IMMUNOGLOBULIN A, SECRETORY) ...

• Immunoglobulin Alterations

  Glycoproteins present in the blood (ANTIBODIES) and in other tissue. They are classified by structure and activity into five classes (IMMUNOGLOBULIN A; IMMUNOGLOBULIN D; IMMUNOGLOBULIN ...

• Colostral IgA

  The principle immunoglobulin in exocrine secretions such as milk, respiratory and intestinal mucin, saliva and tears. The complete molecule (around 400 kD) is composed of ...