Tissue factor pathway inhibitor (TFPI) Recombinant Rabbit mAb (S-4436-30)

Tissue factor pathway inhibitor (TFPI) is a Kunitz-type serine protease inhibitor encoded by the TFPI gene, serving as a key negative regulator of the extrinsic coagulation pathway in vivo. TFPI primarily binds directly to coagulation factor Xa through its Kunitz-2 domain, forming a TFPI-Xa complex, which then binds to the coagulation factor VIIa/tissue factor (TF/VIIa) complex via its Kunitz-1 domain in a calcium-dependent manner, thereby forming a quaternary inhibitory complex that effectively terminates the initiation of the extrinsic coagulation pathway. This mechanism positions TFPI as a "brake" in maintaining the coagulation-anticoagulation balance, and its dysfunction leads to a significantly increased risk of thrombosis. At the pharmacological level, due to its inhibitory effects, TFPI has shown potential as a hemostatic drug target in the treatment of hemophilia—inhibiting TFPI can enhance thrombin generation and improve the bleeding phenotype in hemophilia patients. In addition, TFPI is also considered a contact-phase coagulation inhibitor and may enhance its anticoagulant activity through complex formation with heparin. These multifaceted roles make TFPI of great significance in anticoagulant therapy, hemostatic regulation, and the development of novel antithrombotic agents.