Colonic bacterial infection abrogates eosinophilic pulmonary disease

J Infect Dis. 2006 Jan 15;193(2):223-30. doi: 10.1086/498915. Epub 2005 Dec 14.

Abstract

Induction of immunity to one pathogen in the lungs modifies the microenvironment and alters immunopathological changes that result from a second, unrelated pulmonary infection. However, it is unclear whether immunity generated at distant sites also affects lung immune responses. Here, we show that infection with the gut-restricted bacterium Citrobacter rodentium modifies immunopathological changes that result from pulmonary Cryptococcus neoformans infection. Th2 cytokine-driven pulmonary eosinophilia induced by C. neoformans infection was reduced, and the enhanced Th1 cytokine environment afforded more-rapid clearance of the fungus in C. rodentium-immune mice. The activated and intraepithelial (CD103+) T cell populations that expand after C. neoformans infection were diminished in C. rodentium-immune mice. T cell cross-reactivity was absent, but cross-reactive antibodies were detected. It is of importance to the "hygiene hypothesis" that these data indicate that an immune response induced by a gut-restricted pathogen can modify the immune outcome after pulmonary infection, suggesting that cell-phenotype modifications occur across mucosal sites.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Antibodies, Fungal / blood
  • Antigens, Surface / analysis
  • Bronchoalveolar Lavage Fluid / cytology
  • Citrobacter rodentium / immunology
  • Colitis / complications*
  • Colitis / immunology*
  • Colitis / microbiology
  • Cross Reactions
  • Cryptococcosis / complications*
  • Cryptococcosis / immunology*
  • Cryptococcus neoformans / immunology
  • Disease Models, Animal
  • Enzyme-Linked Immunosorbent Assay
  • Female
  • Lung / pathology
  • Mice
  • Mice, Inbred C57BL
  • Pulmonary Eosinophilia / complications*
  • Pulmonary Eosinophilia / immunology*
  • T-Lymphocytes / immunology

Substances

  • Antibodies, Fungal
  • Antigens, Surface