Neonatal Fc Receptor for IgG (FcRn) Expressed in the Gastric Epithelium Regulates Bacterial Infection in Mice

Mucosal Immunol. 2012 Jan;5(1):87-98. doi: 10.1038/mi.2011.53. Epub 2011 Nov 16.

Abstract

Neonatal Fc receptors for immunoglobulin (Ig)G (FcRn) assume a central role in regulating host IgG levels and IgG transport across polarized epithelial barriers. We have attempted to elucidate the contribution of FcRn in controlling Helicobacter infection in the stomach. C57BL/6J wild-type or FcRn(-/-) mice were infected with Helicobacter heilmannii, and gastric lesions, bacterial load and the levels of antigen-specific IgG in serum and gastric juice were analyzed. The elevated levels of anti-H. heimannii IgG in gastric juice were observed exclusively in wild-type mice but not in FcRn(-/-) mice. In contrast, an increase in lymphoid follicles and bacterial loads along with deeper gastric epithelium invasion were noted in FcRn(-/-) mice. C57BL/6J wild-type or FcRn(-/-) mice were also infected with Helicobacter pylori SS1, and the results of the bacterial load in stomachs of these mice and the anti-H. pylori IgG levels in serum and gastric juice were similar to those from H. heilmannii infection. Our data suggest that FcRn can be functionally expressed in the stomach, which is involved in transcytosis of IgG, and prevent colonization by H. heilmannii and the associated pathological consequences of infection.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Antibodies, Bacterial / immunology
  • Antibodies, Bacterial / metabolism
  • Helicobacter Infections / immunology*
  • Helicobacter heilmannii / immunology*
  • Helicobacter heilmannii / pathogenicity
  • Helicobacter pylori / immunology*
  • Helicobacter pylori / pathogenicity
  • Histocompatibility Antigens Class I / genetics
  • Histocompatibility Antigens Class I / immunology
  • Histocompatibility Antigens Class I / metabolism*
  • Immunoglobulin G / immunology
  • Immunoglobulin G / metabolism
  • Intestinal Mucosa / immunology
  • Intestinal Mucosa / metabolism*
  • Intestinal Mucosa / microbiology
  • Intestinal Mucosa / pathology
  • Mice
  • Mice, Inbred C57BL
  • Mice, Knockout
  • Receptors, Fc / genetics
  • Receptors, Fc / immunology
  • Receptors, Fc / metabolism*
  • Stomach / pathology*
  • Transcytosis
  • Virulence

Substances

  • Antibodies, Bacterial
  • Histocompatibility Antigens Class I
  • Immunoglobulin G
  • Receptors, Fc
  • Fc receptor, neonatal