| 1. |
- Kwiecinski, Jakub, 1985, et al.
(författare)
-
Tissue Plasminogen Activator Coating on Implant Surfaces Reduces Staphylococcus aureus Biofilm Formation
- 2016
-
Ingår i: Applied and Environmental Microbiology. - : American Society for Microbiology. - 0099-2240 .- 1098-5336. ; 82:1, s. 394-401
-
Tidskriftsartikel (refereegranskat)abstract
- Staphylococcus aureus biofilm infections of indwelling medical devices are a major medical challenge because of their high prevalence and antibiotic resistance. As fibrin plays an important role in S. aureus biofilm formation, we hypothesize that coating of the implant surface with fibrinolytic agents can be used as a new method of antibiofilm prophylaxis. The effect of tissue plasminogen activator (tPA) coating on S. aureus biofilm formation was tested with in vitro microplate biofilm assays and an in vivo mouse model of biofilm infection. tPA coating efficiently inhibited biofilm formation by various S. aureus strains. The effect was dependent on plasminogen activation by tPA, leading to subsequent local fibrin cleavage. A tPA coating on implant surfaces prevented both early adhesion and later biomass accumulation. Furthermore, tPA coating increased the susceptibility of biofilm infections to antibiotics. In vivo, significantly fewer bacteria were detected on the surfaces of implants coated with tPA than on control implants from mice treated with cloxacillin. Fibrinolytic coatings (e.g., with tPA) reduce S. aureus biofilm formation both in vitro and in vivo, suggesting a novel way to prevent bacterial biofilm infections of indwelling medical devices.
|
|
| 2. |
- Na, Manli, et al.
(författare)
-
Deficiency of the complement component 3 but not factor B aggravates Staphylococcus aureus septic arthritis in mice.
- 2016
-
Ingår i: Infection and immunity. - 1098-5522. ; 84:4, s. 930-939
-
Tidskriftsartikel (refereegranskat)abstract
- The complement system plays an essential role in the innate immune response and protection against bacterial infections. However, detailed knowledge regarding the role of complement in Staphylococcus aureus (S. aureus) septic arthritis is still largely missing. In this study, we elucidated the role of selected complement proteins in S. aureus septic arthritis. Mice lacking the complement component 3 (C3(-/-)), complement factor B (fB(-/-)), receptor for C3 derived anaphylatoxin C3a (C3aR(-/-)) and wild-type (WT) control mice were intravenously or intraarticularly inoculated with Staphylococcus aureus Newman strain. The clinical course of septic arthritis as well as histopathological and radiological changes in joints were assessed. After intravenous inoculation, arthritis severity and frequency was significantly higher in C3(-/-) mice compared to WT controls, whereas fB(-/-) mice displayed intermediate arthritis severity and frequency. This was in accordance with both histopathological and radiological findings. C3 but not fB deficiency was associated with larger weight loss, more frequent kidney abscesses, as well as higher bacterial burden in kidneys. S. aureus opsonised with C3(-/-) sera displayed decreased uptake by mouse peritoneal macrophages compared with bacteria opsonised with WT or fB(-/-) sera. C3aR deficiency had no effect on the course of hematogenous S. aureus septic arthritis. We conclude that C3 deficiency increases the susceptibility to hematogenous S. aureus septic arthritis and impairs host bacterial clearance, conceivably due to diminished opsonisation and phagocytosis of S. aureus.
|
|
