Polymeric IgA Is Superior to Monomeric IgA

In vitro comparison of the biologic activities of monoclonal monomeric IgA, polymeric IgA, and secretory IgA.

Secretory IgA (S-IgA), a major humoral mediator of mucosal immunity, is a polymeric Ig containing an unusual extra polypeptide, secretory component (SC), added during transcytosis through epithelial cells. Polymeric S-IgA is more effective than monomeric IgA (mIgA) and IgG in neutralizing viruses. It is not known whether this increased efficacy is due solely to the polymeric structure of the mo...

Dimeric and polymeric IgA, but not monomeric IgA, enhance the production of IL-6 by human renal mesangial cells

Depositions of IgA in the renal glomerular mesangial area are a hallmark of IgA nephropathy, and are thought to be crucial for the onset of inflammation processes in IgA nephropathy. In this report we show that human mesangial cells (MC) in vitro bind IgA and that binding of IgA enhances the production of IL-6 by MC. Furthermore we show that the size of IgA is crucial in its capability to enhan...

Brie£ Dehnitive Report Secretory Component as the Receptor for Polymeric Iga on Rat Hepatocytes

The rapid and active transport of polymeric IgA from the blood to the bile (1, 2) is selective (3, 4), which suggests the existence of a specific receptor for this molecule. The liver cells responsible for the transfer have been identified as the hepatocytes by autoradiography and electron microscopy of the livers o f rats killed 5, 30, and 60 min after the injection of radiolabeled IgA (5). 5 ...

Secretory IgA Monoclonal Monomeric IgA, Polymeric IgA, and In Vitro Comparison of the Biologic Activities of

Brie£ DeHnitive Report

The rapid and active transport of polymeric IgA from the blood to the bile (1, 2) is selective (3, 4), which suggests the existence of a specific receptor for this molecule. The liver cells responsible for the transfer have been identified as the hepatocytes by autoradiography and electron microscopy of the livers o f rats killed 5, 30, and 60 min after the injection of radiolabeled IgA (5). 5 ...