Biomaterial centered infection is an important cause of the failure of prosthetic implants and organs. Almost all such infections, early and late, occur in the periprosthetic space and are caused by low levels of contamination with microbes implanted at the time of surgery. The inability of the host to eliminate relatively few bacteria is most likely due to failure of oxidative killing by the neutrophil in the presence of the foreign body. We have carefully explored, in the previous grant period, the direct interactions between neutrophilic respiratory burst and various biomaterials. Our evidence and that of others supports the idea that proteins adsorbed to certain polymers bind to specific receptors on the neutrophil and prime it to excessive production of reactive oxygen intermediates (ROI) when triggered by contaminating bacterial products (Staphylococcus or lipopolysaccharide) or inflammatory cytokines like tumor necrosis factor. As a result of excessive production of ROI, the neutrophils are likely to be impaired in their capacity to kill bacteria. In support of this idea is the fact that may adsorbed proteins can not only bind and prime neutrophils, but they can also specifically bind (opsonize) bacteria and bacterial products. Such proteins include the plasma protein (fibrinogen), the extracellular matrix proteins (fibronectin, laminin), the platelet derived protein (thrombospondin), and lipopolysaccharide binding protein (LBP). The prosthetic surface would then become a platform for infection because it adsorbs proteins which both bind the bacteria and the neutrophil into a configuration which leads to massive and prolonged production of ROI which in turn downregulates oxidative killing. Furthermore, such a complex biomaterial/protein/bacterial surface is likely to stimulate macrophages: 1) to secrete cytokines which will downregulate phagocytic killing; and 2) to secrete nitric oxide which has the capacity to react with and quench the ROI needed to kill bacteria. The present proposal is designed to systematically elucidate the interactions between a few selected biomaterials and suspect opsonic proteins in order to determine how such proteins bind to biomaterial and how the complexes fix bacteria to the polymeric surface. Once it becomes clear that certain opsonic proteins can be adsorbed onto biomaterials and bind bacteria there, the effects of the biomaterial/protein/bacterial complex on neutrophil and macrophage responses can be determined. The ultimate goal is a more complete understanding of the net effect of these interactions on oxidative killing of bacteria in the presence of a prosthetic implant.

Agency
National Institute of Health (NIH)
Institute
National Institute of General Medical Sciences (NIGMS)
Type
Research Project (R01)
Project #
5R01GM041734-09
Application #
2900707
Study Section
Surgery, Anesthesiology and Trauma Study Section (SAT)
Project Start
1989-12-01
Project End
2001-03-31
Budget Start
1999-04-01
Budget End
2000-03-31
Support Year
9
Fiscal Year
1999
Total Cost
Indirect Cost
Name
University of Pittsburgh
Department
Surgery
Type
Schools of Medicine
DUNS #
053785812
City
Pittsburgh
State
PA
Country
United States
Zip Code
15213
Green, Jerril; Doughty, Lesley; Kaplan, Sandra S et al. (2002) The tissue factor and plasminogen activator inhibitor type-1 response in pediatric sepsis-induced multiple organ failure. Thromb Haemost 87:218-23
Kaplan, S S; Simmons, R L (2001) Effect of plasma and matrix proteins on defensin-induced impairment of phagocytic killing by adherent neutrophils. J Biomed Mater Res 57:1-7
Kaplan, S S; Heine, R P; Simmons, R L (1999) Defensins impair phagocytic killing by neutrophils in biomaterial-related infection. Infect Immun 67:1640-5
Doughty, L; Carcillo, J A; Kaplan, S et al. (1998) Plasma nitrite and nitrate concentrations and multiple organ failure in pediatric sepsis. Crit Care Med 26:157-62
Doughty, L; Carcillo, J A; Kaplan, S et al. (1998) The compensatory anti-inflammatory cytokine interleukin 10 response in pediatric sepsis-induced multiple organ failure. Chest 113:1625-31
Kaplan, S S; Lancaster Jr, J R; Basford, R E et al. (1996) Effect of nitric oxide on staphylococcal killing and interactive effect with superoxide. Infect Immun 64:69-76
Kaplan, S S; Basford, R E; Jeong, M H et al. (1996) Biomaterial-neutrophil interactions: dysregulation of oxidative functions of fresh neutrophils induced by prior neutrophil-biomaterial interaction. J Biomed Mater Res 30:67-75
Wong, H R; Carcillo, J A; Burckart, G et al. (1996) Nitric oxide production in critically ill patients. Arch Dis Child 74:482-9
Doughty, L A; Kaplan, S S; Carcillo, J A (1996) Inflammatory cytokine and nitric oxide responses in pediatric sepsis and organ failure. Crit Care Med 24:1137-43
Kaplan, S S (1994) Biomaterial-host interactions: consequences, determined by implant retrieval analysis. Med Prog Technol 20:209-30

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