Protective role of IL-1β against post-arthroplasty Staphylococcus aureus infection

J Orthop Res. 2011 Oct;29(10):1621-6. doi: 10.1002/jor.21414. Epub 2011 Mar 28.


MyD88 is an adapter molecule that is used by both IL-1R and TLR family members to initiate downstream signaling and promote immune responses. Given that IL-1β is induced after Staphylococcus aureus infections and TLR2 is activated by S. aureus lipopeptides, we hypothesized that IL-1β and TLR2 contribute to MyD88-dependent protective immune responses against post-arthroplasty S. aureus infections. To test this hypothesis, we used a mouse model of a post-arthroplasty S. aureus infection to compare the bacterial burden, biofilm formation and neutrophil recruitment in IL-1β-deficient, TLR2-deficient and wild-type (wt) mice. By using in vivo bioluminescence imaging, we found that the bacterial burden in IL-1β-deficient mice was 26-fold higher at 1 day after infection and remained 3- to 10-fold greater than wt mice through day 42. In contrast, the bacterial burden in TLR2-deficient mice did not differ from wt mice. In addition, implants harvested from IL-1β-deficient mice had more biofilm formation and 14-fold higher adherent bacteria compared with those from wt mice. Finally, IL-1β-deficient mice had ∼50% decreased neutrophil recruitment to the infected postoperative joints than wt mice. Taken together, these findings suggest a mechanism by which IL-1β induces neutrophil recruitment to help control the bacterial burden and the ensuing biofilm formation in a post-surgical joint.

Publication types

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

MeSH terms

  • Animals
  • Arthroplasty
  • Biofilms / growth & development
  • Bone Wires / microbiology
  • Interleukin-1beta / metabolism*
  • Male
  • Mice
  • Mice, Congenic
  • Mice, Inbred C57BL
  • Myeloid Differentiation Factor 88 / metabolism
  • Neutrophil Infiltration
  • Prosthesis-Related Infections / immunology*
  • Prosthesis-Related Infections / metabolism
  • Staphylococcal Infections / immunology*
  • Staphylococcal Infections / metabolism
  • Staphylococcus aureus
  • Toll-Like Receptor 2 / metabolism*


  • Interleukin-1beta
  • Myd88 protein, mouse
  • Myeloid Differentiation Factor 88
  • Tlr2 protein, mouse
  • Toll-Like Receptor 2