Rapid tissue factor induction by oral streptococci and monocyte-IL-1beta.
The ability of pro-inflammatory cytokines to promote coagulation prompted the hypothesis that pro-inflammatory cytokines induced by oral streptococci might play a role in the pathogenesis of viridans endocarditis. We used supernatant fluids from peripheral blood mononuclear monocyte (PBMC) cultures, stimulated for just 4-6 hrs with representative streptococcal isolates, to study cytokines that promoted endothelial tissue factor (TF) activity. Neutralizing antibodies demonstrated that interleukin-1beta (IL-1beta) was a major early endothelial TF inducer, and that recombinant IL-1beta was comparable with the supernatant fluid in activity. IL-1beta-rich supernatant fluids from oral streptococci-stimulated or lipopolysaccharide-stimulated PBMC cultures up-regulated the expression of endothelial ICAM-1 and E-selectin. These molecules could help trap TF-producing monocytes or dendritic cells bearing streptococci at the site. Thus, the rapid IL-1beta-inducing capacity of oral streptococci could facilitate the early deposition of bacteria in fibrin clots and promote endocarditis.
Hahn
C-L
CL
Department of Endodontics, School of Dentistry, Richmond, VA 23298-0566, USA.
Best
A M
AM
Tew
J G
JG
D000704:Analysis of Variance; D016470:Bacteremia / Q000382:microbiology*; D002448:Cell Adhesion; D002478:Cells, Cultured; D017077:Culture Media, Conditioned / Q000494:pharmacology; D003713:Dendritic Cells / Q000502:physiology; D019040:E-Selectin / Q000378:metabolism; D042783:Endothelial Cells / Q000382:microbiology; D004730:Endothelium, Vascular / Q000166:cytology / Q000382:microbiology*; D006801:Humans; D018799:Intercellular Adhesion Molecule-1 / Q000378:metabolism; D053583:Interleukin-1beta / Q000494:pharmacology / Q000502:physiology*; D008070:Lipopolysaccharides; D009000:Monocytes / Q000187:drug effects / Q000378:metabolism / Q000382:microbiology*; D009055:Mouth / Q000382:microbiology; D011994:Recombinant Proteins / Q000494:pharmacology; D013925:Thromboplastin / Q000096:biosynthesis* / Q000502:physiology; D015854:Up-Regulation; D034363:Viridans Streptococci / Q000472:pathogenicity*
D017077:Culture Media, Conditioned; D019040:E-Selectin; D053583:Interleukin-1beta; D008070:Lipopolysaccharides; D011994:Recombinant Proteins; D018799:Intercellular Adhesion Molecule-1; D013925:Thromboplastin