American Society of Hirudotherapy

Tissue factor/TFPI and blood cells.

Review published in Thrombosis research (2011)

Last Updated: June 18, 2026Reviewed by: ASH Editorial Board
Research article — evidence reviewArticle reference
Evidence: Narrative reviewDrug DevelopmentSalivary PharmacologyOsterud · Thrombosis research, 2011

Abstract

Vascular injury-induced access of blood to tissue factor (TF) leads to the formation of a TF-FVII/FVIIa complex and the triggering of blood coagulation. The activated TF-dependent pathway is regulated by Tissue Factor Pathway Inhibitor (TFPI), which binds and inhibits FXa, but more importantly forms an inactive quaternary complex with TF-FVIIa-FXa, effectively shutting off the TF activity. The old view of TF residing in extravascular sites exclusively has recently been challenged by several reports on TF expression in various blood cells. The latter arena has unfortunately been marred by many contradictions, apparently related to inferior tools and/or study design, notably the widespread use of antibodies with inferior and misleading specificity and TF activity assays of low sensitivity/specificity. Our own studies along with many other reports, compels the conclusion that in blood of healthy individuals TF is exclusively associated with and expressed in circulating monocytes. In this short review the distribution of TF and TFPI in blood is discussed.

Abstract sourced from PubMed (NCBI) for the cited record. See the original publication for the authoritative version.

Publication typeJournal ArticleReview
Indexed MeSH termsAnimalsBlood CellsBlood CoagulationBlood PlateletsCell-Derived MicroparticlesCoagulantsEosinophilsHemophilia AHumansLipoproteinsMonocytesNeutrophils

Summary

Vascular injury-induced access of blood to tissue factor (TF) leads to the formation of a TF-FVII/FVIIa complex and the triggering of blood coagulation. The activated TF-dependent pathway is regulated by Tissue Factor Pathway Inhibitor (TFPI), which binds and inhibits FXa, but more importantly...

Why This Matters for Hirudotherapy

This review discussed the distribution of tissue factor (TF) and tissue factor pathway inhibitor (TFPI) in blood cells, concluding that in healthy individuals TF is exclusively associated with circulating monocytes while noting contradictions in prior literature due to inferior antibodies and assays. The relevance to ASH is peripheral — the abstract addresses coagulation initiation and regulation but involves no leeches, hirudin, or leech-derived molecules. Caveat: no leech involvement; indirect relevance as general coagulation biology context only.

Citation

Tissue factor/TFPI and blood cells.

Osterud · Thrombosis research, 2011

Added to ASH library: May 28, 2026 · Site last updated: June 18, 2026

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