Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0014118 (endocarditis)
 15,629 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Fibrin is the primary constituent of the vegetation in infective endocarditis, and tissue factor expression is a major mechanism of coagulation activation on infected valves. To determine which cells may participate in coagulation activation in this setting, expression of procoagulant activity (PCA; shown to be tissue factor) was studied in cultured endothelial and stromal cells derived from human cardiac valves. Endothelial cells had negligible PCA (99 +/- 50 mU/10(5) cells, mean +/- 1 standard deviation) unless stimulated by lipopolysaccharide or interleukin-1, which increased PCA to 5,592 +/- 1,482 and 5,901 +/- 1,497 mU/10(5) cells, respectively, in 6 h. Incubation of cells with viable enterococci or viridans streptococci or with an enterococcal cell wall preparation did not induce PCA. Cultured valve stromal cells constitutively expressed high levels of PCA (14,276 +/- 8,738 mU/10(5) cells) which was not changed with exposure to interleukin-1. PCAs of stromal or stimulated endothelial cells from valves of both right and left sides of the heart were comparable. The results suggest that endothelial cells may contribute to fibrin deposition during infection if stimulated, but PCA is not directly induced by bacteria. Stromal cells could contribute PCA if exposed to blood in the course of valve injury.
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PMID:Effects of interleukin-1, lipopolysaccharide, and streptococci on procoagulant activity of cultured human cardiac valve endothelial and stromal cells. 249 62

Staphylococcus aureus is one of the most significant pathogens in human sepsis and endocarditis. A hallmark of these endovascular S. aureus infections is that the coagulation system is triggered by a tissue factor (TF)-dependent pathway. This study demonstrates that highly purified S. aureus peptidoglycan, lipoteichoic acid (LTA) and TSST-1 increase TF mRNA and TF surface protein in human umbilical vein endothelial cells (ECs). Concomitantly, peptidoglycan- and LTA-activated ECs express significant TF-dependent procoagulant activity (TF PCA). In addition peptidoglycan, but not LTA or TSST-1, induced surface expression of the EC inflammation markers ICAM-1 and VCAM-1, which supported the adhesion of monocytes to these ECs. During the coculture of peptidoglycan-activated ECs and adherent monocytes, a marked additional increase of TF PCA was observed. Marginal increases in TF PCA were observed in cocultures of monocytes with LTA- or TSST-1-activated ECs. This study defines in particular staphylococcal peptidoglycan, previously known as a potent initiator of TF PCA in monocytes, as also being an activator of a coagulant response in human ECs that is further intensified by the presence of surface-bound monocytes.
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PMID:Staphylococcal peptidoglycan initiates an inflammatory response and procoagulant activity in human vascular endothelial cells: a comparison with highly purified lipoteichoic acid and TSST-1. 1803 38