Polymorphonuclear leukocytes regulate the plasminogen-activating system of cultured endothelial cells.
Exposure of bovine pulmonary artery endothelial cells (BEC) to polymorphonuclear leukocytes (PMN) (1 x 10(6)/ml) stimulated by opsonized zymosan (OZ-PMN) decreased plasminogen activator (PA) activity in conditioned medium by as much as 98% as compared to controls. Unstimulated PMN (U-PMN) (1 x 10(6)/ml), after an initial enhancement, decreased PA activity 95%. Low concentrations of U-PMN and OZ-PMN enhanced and high concentrations depressed PA activity. The decline in PA activity was not associated with an increased endothelial cell injury. The suppression of PA activity by OZ-PMN was associated with a 7-fold increase in activity of PA inhibitor 1 (PAI-1). PMN did not affect PA after its secretion, suggesting that modulation of endothelial cells by PMN changes the net activities of PA and PAI-1 in the conditioned medium.
Gilboa
N
N
New York State Department of Health, Wadsworth Center for Laboratories and Research, Albany 12201.
Neumann
P H
PH
Del Vecchio
P J
PJ
Gudewicz
P W
PW
D000818:Animals; D002478:Cells, Cultured; D004730:Endothelium, Vascular / Q000378:metabolism*; D005342:Fibrinolysis; D006023:Glycoproteins / Q000378:metabolism; D006801:Humans; D066298:In Vitro Techniques; D009504:Neutrophils / Q000502:physiology*; D010960:Plasminogen Activators / Q000378:metabolism*; D015849:Plasminogen Inactivators
D006023:Glycoproteins; D015849:Plasminogen Inactivators; D010960:Plasminogen Activators