[Effect of monoclonal antibody against human tissue factor pathway inhibitor on plasma coagulation time]

The purpose of this study was to evaluate the influences of the monoclonal antibody against human tissue factor pathway inhibitor (TFPI), McAb4F8, on prothrombin time (PT) and activated partial thromboplatin time (APTT). The results showed that PT and APTT were prolonged by exogenous TFPI. Dilute thromboplastin coagulation time was shortened with a dose-dependent manner by McAb4f8. Low molecular weight heparin (LMWH) prolonged significantly PT and APTT, and this effect ws weakened by an antibody against human AT III. McAb4F8 was also proved to shorten dilute thromboplastin coagulation time of factor IX deficient plasma. These results indicated that the tissue factor pathway plays an important role not only in physiological coagulation but also in hemorrhage of hemophilia.