[Cell receptors for active blood coagulation factors]

Thrombin and Xa factor of blood coagulation form the relation with cell surface of normal human fibroblasts. The relation of serine proteases with cell surface is specific. Catalytically inactivated proteases exhibit low coagulation activity and little capability of nonspecific cell binding. The components of cell surface called receptors are released to the incubation medium and have anticoagulation properties. The biological significance of "floating receptors" is determined by their capacity to bind serine proteases and to control cell homeostasis.