Identification of surface epitopes of human coagulation factor Va that are important for interaction with activated protein C and heparin
Inactivation of factor Va (FVa) by activated protein C (APC) is a key reaction in the down- regulation of thrombin formation. FVa inactivation by APC is correlated with a loss of FXa cofactor activity as a result of three proteolytic cleavages in the FVa heavy chain at Arg(306), Arg(506), and Arg(679). Recently, we have shown that heparin specifically inhibits the APC- mediated cleavage at Arg(506
