Failure to induce IFN-β production during Staphylococcus aureus infection contributes to pathogenicity

J Immunol. 2012 Nov 1;189(9):4537-45. doi: 10.4049/jimmunol.1201111. Epub 2012 Sep 24.

Abstract

The importance of type I IFNs in the host response to viral infection is well established; however, their role in bacterial infection is not fully understood. Several bacteria (both Gram-positive and -negative) have been shown to induce IFN-β production in myeloid cells, but this IFN-β is not always beneficial to the host. We examined whether Staphylococcus aureus induces IFN-β from myeloid phagocytes, and if so, whether it is helpful or harmful to the host to do so. We found that S. aureus poorly induces IFN-β production compared with other bacteria. S. aureus is highly resistant to degradation in the phagosome because it is resistant to lysozyme. Using a mutant that is more sensitive to lysozyme, we show that phagosomal degradation and release of intracellular ligands is essential for induction of IFN-β and inflammatory chemokines downstream of IFN-β. Further, we found that adding exogenous IFN-β during S. aureus infection (in vitro and in vivo) was protective. Together, the data demonstrate that failure to induce IFN-β production during S. aureus infection contributes to pathogenicity.

Publication types

  • Research Support, N.I.H., Extramural

MeSH terms

  • Animals
  • Cells, Cultured
  • Disease Models, Animal
  • Humans
  • Interferon-beta* / antagonists & inhibitors
  • Interferon-beta* / biosynthesis
  • Interferon-beta* / genetics
  • Mice
  • Mice, Inbred C57BL
  • Mice, Knockout
  • Mutation / immunology
  • Staphylococcal Infections / blood
  • Staphylococcal Infections / immunology*
  • Staphylococcal Infections / microbiology*
  • Staphylococcus aureus / genetics
  • Staphylococcus aureus / immunology*
  • Staphylococcus aureus / pathogenicity*

Substances

  • Interferon-beta