Caveolin-1-deficient mice show defects in innate immunity and inflammatory immune response during Salmonella enterica serovar Typhimurium infection

Infect Immun. 2006 Dec;74(12):6665-74. doi: 10.1128/IAI.00949-06. Epub 2006 Sep 18.

Abstract

A number of studies have shown an association of pathogens with caveolae. To this date, however, there are no studies showing a role for caveolin-1 in modulating immune responses against pathogens. Interestingly, expression of caveolin-1 has been shown to occur in a regulated manner in immune cells in response to lipopolysaccharide (LPS). Here, we sought to determine the role of caveolin-1 (Cav-1) expression in Salmonella pathogenesis. Cav-1(-/-) mice displayed a significant decrease in survival when challenged with Salmonella enterica serovar Typhimurium. Spleen and tissue burdens were significantly higher in Cav-1(-/-) mice. However, infection of Cav-1(-/-) macrophages with serovar Typhimurium did not result in differences in bacterial invasion. In addition, Cav-1(-/-) mice displayed increased production of inflammatory cytokines, chemokines, and nitric oxide. Regardless of this, Cav-1(-/-) mice were unable to control the systemic infection of Salmonella. The increased chemokine production in Cav-1(-/-) mice resulted in greater infiltration of neutrophils into granulomas but did not alter the number of granulomas present. This was accompanied by increased necrosis in the liver. However, Cav-1(-/-) macrophages displayed increased inflammatory responses and increased nitric oxide production in vitro in response to Salmonella LPS. These results show that caveolin-1 plays a key role in regulating anti-inflammatory responses in macrophages. Taken together, these data suggest that the increased production of toxic mediators from macrophages lacking caveolin-1 is likely to be responsible for the marked susceptibility of caveolin-1-deficient mice to S. enterica serovar Typhimurium.

Publication types

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

MeSH terms

  • Animals
  • Caveolin 1 / deficiency
  • Caveolin 1 / genetics
  • Caveolin 1 / physiology*
  • Cytokines / genetics
  • Cytokines / metabolism
  • Granuloma / immunology
  • Granuloma / microbiology
  • Granuloma / pathology
  • Immunity, Innate* / genetics
  • Lipopolysaccharides / immunology
  • Liver / immunology
  • Liver / pathology
  • Macrophages / immunology*
  • Macrophages / microbiology
  • Mice
  • Mice, Knockout
  • Neutrophils / immunology
  • Nitric Oxide / metabolism
  • STAT3 Transcription Factor / metabolism
  • Salmonella Infections / genetics
  • Salmonella Infections / immunology*
  • Salmonella Infections / pathology
  • Salmonella typhimurium*
  • Spleen / immunology
  • Spleen / pathology

Substances

  • Caveolin 1
  • Cytokines
  • Lipopolysaccharides
  • STAT3 Transcription Factor
  • Stat3 protein, mouse
  • Nitric Oxide