title: Interferon-gamma protects against biomaterial-associated Staphylococcus epidermidis infection in mice.
abstract: Survival of Staphylococcus epidermidis inside macrophages has been recognized as a pivotal process in the pathogenesis of biomaterial-associated infection (BAI). Interferon (IFN)-gamma is a potent activator of macrophages. This study examined whether subcutaneous injections of IFN-gamma can reverse macrophage deactivation induced by implanted biomaterials. Mice received subcutaneous implants combined with an injection of 106 S. epidermidis to induce an experimental BAI. Subsequently, 3 groups of mice received subcutaneous injections of 25,000 IU IFN-gamma 3 times weekly, 10,000 IU IFN-gamma 3 times in 2 weeks, or saline 3 times weekly (saline control), respectively. A fourth group received no injections (control). Segments and tissues of the IFN-gamma-treated mice were significantly less (P<.05) culture positive than those of the control groups. Histologically, the high numbers of intracellularly persisting gram-positive cocci observed in the control mice were absent in the IFN-gamma-treated mice. These data indicate that IFN-gamma protects against experimental BAI.
authors.affiliation: Department of Medical Microbiology, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands. Boelensjj@yahoo.com
authors.forename: J J
authors.initials: JJ
authors.lastname: Boelens
authors.forename: T
authors.initials: T
authors.lastname: van der Poll
authors.forename: J
authors.initials: J
authors.lastname: Dankert
authors.forename: S A
authors.initials: SA
authors.lastname: Zaat
mesh_terms: D000818:Animals; D002408:Catheters, Indwelling / Q000009:adverse effects*; D005260:Female; D005549:Foreign-Body Reaction; D007279:Injections, Subcutaneous; D007371:Interferon-gamma / Q000008:administration & dosage / Q000627:therapeutic use*; D008264:Macrophages / Q000382:microbiology; D051379:Mice; D008810:Mice, Inbred C57BL; D013203:Staphylococcal Infections / Q000517:prevention & control*; D013212:Staphylococcus epidermidis
chemical_list: D007371:Interferon-gamma