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Dependence of antibody-mediated presentation of antigen on FcRn.

ABSTRACT: The neonatal Fc receptor for IgG (FcRn) is a distant member of the MHC class I protein family. It binds IgG and albumin in a pH-dependent manner and protects these from catabolism by diverting them from a degradative fate in lysosomes. In addition, FcRn-mediated IgG transport across epithelial barriers is responsible for the transmission of IgG from mother to infant and can also enhance IgG-mediated antigen uptake across mucosal epithelia. We now show a previously undescribed role for FcRn in mediating the presentation of antigens by dendritic cells when antigens are present as a complex with antibody by uniquely directing multimeric immune complexes, but not monomeric IgG, to lysosomes.

SUBMITTER: Qiao SW

PROVIDER: S-EPMC2453734 | biostudies-literature | 2008 Jul

REPOSITORIES: biostudies-literature

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Dependence of antibody-mediated presentation of antigen on FcRn.

Qiao Shuo-Wang SW Kobayashi Kanna K Johansen Finn-Eirik FE Sollid Ludvig M LM Andersen Jan Terje JT Milford Edgar E Roopenian Derry C DC Lencer Wayne I WI Blumberg Richard S RS

Proceedings of the National Academy of Sciences of the United States of America 20080701 27

The neonatal Fc receptor for IgG (FcRn) is a distant member of the MHC class I protein family. It binds IgG and albumin in a pH-dependent manner and protects these from catabolism by diverting them from a degradative fate in lysosomes. In addition, FcRn-mediated IgG transport across epithelial barriers is responsible for the transmission of IgG from mother to infant and can also enhance IgG-mediated antigen uptake across mucosal epithelia. We now show a previously undescribed role for FcRn in me ...[more]

PMID: 18599440

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