Urokinase on Human Monocytes: Catalytic Efficiency and Susceptibility to Inactivation by Plasminogen Activator Inhibitors
نویسنده
چکیده
We compared urokinase-type plasminogen activator (u-PA) in fluid phase and u-PA bound with its receptor on human blood monocytes with respect to proteolytic activity and susceptibility to inactivation by the plasminogen activator inhibitors PAl-i and PAI-2. Receptor-bound u-PA is catalytically twice as efficient as fluid-phase u-PA. Fluidphase u-PA is susceptible to rapid inhibition by PAl-i and PAI-2 at an estimated PAI:u-PA molar ratio of 2:1 . In contrast. u-PA bound to endogenously occupied receptors is inhibited by PAI-2 only at PAI:u-PA molar ratios of 20:1.
منابع مشابه
Functional characteristics of receptor-bound urokinase on human monocytes: catalytic efficiency and susceptibility to inactivation by plasminogen activator inhibitors.
We compared urokinase-type plasminogen activator (u-PA) in fluid phase and u-PA bound with its receptor on human blood monocytes with respect to proteolytic activity and susceptibility to inactivation by the plasminogen activator inhibitors PAI-1 and PAI-2. Receptor-bound u-PA is catalytically twice as efficient as fluid-phase u-PA. Fluid-phase u-PA is susceptible to rapid inhibition by PAI-1 a...
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