Protein A is a virulence factor in Staphylococcus aureus arthritis and septic death

Microb Pathog. 2002 Nov;33(5):239-49. doi: 10.1006/mpat.2002.0533.


Staphylococcal protein A (SpA), a cell wall anchored protein of Staphylococcus aureus, has the ability to interact with several host components, possibly indicating a role as a virulence factor in S. aureus infections. In this study, the contribution of SpA to bacterial virulence was investigated in a murine model of S. aureus arthritis. Intravenous inoculation of S. aureus wild-type strain Newman gave rise to more severe arthritis and higher mortality than the isogenic spa mutant strain DU5873. The wild-type strain caused more in vitro spleen cell proliferation than the SpA-deficient strain. However, IL-6 and TNF-alpha levels were higher after stimulation with thespa mutant strain compared to the wild-type strain. To conclude, our results clearly indicate that SpA is a virulence factor of S. aureus in murine septic arthritis.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Arthritis, Infectious / blood
  • Arthritis, Infectious / immunology
  • Arthritis, Infectious / microbiology*
  • Complement C3 / analysis
  • Cytokines / analysis
  • Gene Expression Regulation, Bacterial
  • Immunoglobulins / analysis
  • Mice
  • Spleen / cytology
  • Spleen / growth & development
  • Spleen / metabolism
  • Staphylococcal Infections / blood
  • Staphylococcal Infections / immunology
  • Staphylococcal Infections / microbiology*
  • Staphylococcal Protein A / metabolism*
  • Staphylococcus aureus / genetics
  • Staphylococcus aureus / metabolism
  • Staphylococcus aureus / pathogenicity*
  • Survival Analysis
  • Virulence Factors / metabolism*


  • Complement C3
  • Cytokines
  • Immunoglobulins
  • Staphylococcal Protein A
  • Virulence Factors