Biochem/physiol Actions

Inhibition of tissue factor function and thrombus formation by TFPI (tissue factor pathway inhibitor) is a major reason for ischemic stroke in carotid artery disease. The main function of TFPI is to regulate blood coagulation system. It possess both anticoagulant and antimetastatic action. This protein is prominently localized to medial and neointimal smooth muscle cells, macrophages and T-cells of atherosclerotic plaques. Upregulation of the TFPI gene is observed in atherosclerosis. Mutation in the TFPI gene leads to the risk of coronary artery disease.

General description

The TFPI (tissue factor pathway inhibitor) gene is mapped to human chromosome 2q32.1. This protein exists in two isoforms TFPIα and TFPIβ.

Tissue factor pathway inhibitor (TFPI) also known as Extrinsic pathway inhibitor (EPI), Lipoprotein - associated coagulation inhibitor (LACI), is a plasma proteinase inhibitor synthesized by vascular endothelial cells and part of it is associated with glycosaminoglycans of these cells. TFPI is a single-chain polypeptide which can reversibly inhibit Factor Xa (Xa) and Thrombin (Factor IIa). TFPI is a secreted protein with a N­terminal acidic region, three Kunitz (K) domains separated with by two linker regions, and a C­terminal basic region. The first K domain inhibits coagulation factor VIIa complexed to tissue factor (TF); The second K domain inhibits factor Xa; The third K domain binds to heparin; The C­terminal basic region may have several functions. For example, it plays an important role in binding of TFPI to cell surfaces.

Physical form

Lyophilized from 0.22 µm filtered solution in PBS, pH 7.4. Normally Mannitol or Trehalose is added as protectants before lyophilization.

Reconstitution

Centrifuge the vial prior to opening. Reconstitute in sterile PBS, pH 7.4 to a concentration of 50 µg/mL. Do not vortex. This solution can be stored at 2-8°C for up to 1 month. For extended storage, it is recommended to store at -20°C.