Tissue factor pathway inhibitor

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Protein TFPI PDB 1adz.png
Available structures
PDB Ortholog search: PDBe RCSB
Aliases TFPI , EPI, LACI, TFI, TFPI1, tissue factor pathway inhibitor
External IDs OMIM: 152310 MGI: 1095418 HomoloGene: 4579 GeneCards: TFPI
RefSeq (mRNA)



RefSeq (protein)


Location (UCSC) Chr 2: 187.46 – 187.57 Mb Chr 2: 84.26 – 84.31 Mb
PubMed search [3] [4]
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Tissue factor pathway inhibitor (or TFPI) is a single-chain polypeptide which can reversibly inhibit factor Xa (Xa). While Xa is inhibited, the Xa-TFPI complex can subsequently also inhibit the FVIIa-tissue factor complex. TFPI contributes significantly to the inhibition of Xa in vivo, despite being present at concentrations of only 2.5 nM.


The gene for TFPI is located on chromosome 2q31-q32.1, and has nine exons which span 70 kb. A similar gene, termed TFPI2 , has been identified on chromosome 7, at locus 7q21.3; in addition to TFPI activity, its product also has retinal pigment epithelial cell growth-promoting properties.

Protein structure

TFPI has a relative molecular mass of 34,000 to 40,000 depending on the degree of proteolysis of the C-terminal region.

TFPI consists of a highly negatively charged amino-terminus, three tandemly linked Kunitz domains, and a highly positively charged carboxy-terminus. With its Kunitz domains, TFPI exhibits significant homology with human inter-alpha-trypsin inhibitor and bovine basic pancreatic trypsin inhibitor.


Tissue factor pathway inhibitor has been shown to interact with Factor X. [5]

See also

Related Research Articles

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<span class="mw-page-title-main">Factor X</span> Mammalian protein found in Homo sapiens

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<span class="mw-page-title-main">Factor XI</span> Mammalian protein found in Homo sapiens

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<span class="mw-page-title-main">Protein Z</span> Protein involved in blood clotting

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<span class="mw-page-title-main">Plasma kallikrein</span>

Plasma kallikrein is an enzyme. This enzyme catalyses the following chemical reaction

<span class="mw-page-title-main">Apolipoprotein H</span> Protein-coding gene in humans

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<span class="mw-page-title-main">TFPI2</span> Protein-coding gene in the species Homo sapiens

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<span class="mw-page-title-main">F2RL2</span> Protein-coding gene in the species Homo sapiens

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<span class="mw-page-title-main">HGFAC</span> Protein-coding gene in humans

Hepatocyte growth factor activator is a protein that in humans is encoded by the HGFAC gene.

<span class="mw-page-title-main">Kunitz domain</span>

Kunitz domains are the active domains of proteins that inhibit the function of protein degrading enzymes or, more specifically, domains of Kunitz-type are protease inhibitors. They are relatively small with a length of about 50 to 60 amino acids and a molecular weight of 6 kDa. Examples of Kunitz-type protease inhibitors are aprotinin, Alzheimer's amyloid precursor protein (APP), and tissue factor pathway inhibitor (TFPI). Kunitz STI protease inhibitor, the trypsin inhibitor initially studied by Moses Kunitz, was extracted from soybeans.

Four drugs from the class of direct Xa inhibitors are marketed worldwide. Rivaroxaban (Xarelto) was the first approved FXa inhibitor to become commercially available in Europe and Canada in 2008. The second one was apixaban (Eliquis), approved in Europe in 2011 and in the United States in 2012. The third one edoxaban was approved in Japan in 2011 and in Europe and the US in 2015. Betrixaban (Bevyxxa) was approved in the US in 2017.


  1. 1 2 3 GRCh38: Ensembl release 89: ENSG00000003436 - Ensembl, May 2017
  2. 1 2 3 GRCm38: Ensembl release 89: ENSMUSG00000027082 - Ensembl, May 2017
  3. "Human PubMed Reference:". National Center for Biotechnology Information, U.S. National Library of Medicine.
  4. "Mouse PubMed Reference:". National Center for Biotechnology Information, U.S. National Library of Medicine.
  5. Broze, G J; Warren L A; Novotny W F; Higuchi D A; Girard J J; Miletich J P (Feb 1988). "The lipoprotein-associated coagulation inhibitor that inhibits the factor VII-tissue factor complex also inhibits factor Xa: insight into its possible mechanism of action". Blood. UNITED STATES. 71 (2): 335–43. doi: 10.1182/blood.V71.2.335.335 . ISSN   0006-4971. PMID   3422166.

Further reading