P-selectin induction of tissue factor biosynthesis and expression.

P-selectin on activated platelets and stimulated endothelial cells mediates cell adhesion with monocytes and neutrophils. Since activated platelets induce tissue factor on monocytes, we examined the effect of P-selectin on this activity. Chinese hamster ovary cells expressing P-selectin stimulated tissue factor activity in purified monocytes whereas untransfected Chinese hamster ovary cells and CHO cells expressing E-selectin did not. Anti-P-selectin antibodies inhibited these effects. Incubation of CHO:P-selectin with monocytes stimulates tissue factor mRNA development and the expression of tissue factor antigen on the monocyte surface. These results indicate that P-selectin upregulates the expression of tissue factor on monocytes.