Reaction of Fibrin-Bound Thrombin with a Covalent Antithrombin-Heparin Complex Results in an Anticoagulant Surface.

Abstract Thrombin bound to fibrin is protected from inhibition by mixtures of antithrombin (AT) and heparin (H). Resistance of thrombin to reaction with AT + H when fibrin is present results from the formation of a ternary fibrin:thrombin:H complex. However, recent investigations using an antithrombin-heparin conjugate (ATH) showed that the covalent ATH complex rapidly inhibits fibrin-bound thrombin, with the thrombin-ATH …