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Updated: May 18, 2026
03:53
Extracellular Vesicle Tissue Factor Activity Assay
Published on: December 29, 2023
Regulation of tissue factor coagulant activity on cell surfaces
1Department of Cellular and Molecular Biology, Center for Biomedical Research, The University of Texas Health Science Center, Tyler, TX, USA.
Journal of Thrombosis and Haemostasis : JTH
|September 26, 2012
Summary
Tissue factor (TF) regulates blood clotting and cell signaling. Its activity is controlled by mechanisms beyond protein levels, crucial for preventing thrombosis and maintaining hemostasis.
Area of Science:
- Biochemistry
- Cell Biology
- Hematology
Background:
- Tissue factor (TF) is vital for initiating blood coagulation via the TF-FVIIa complex.
- TF triggers cell signaling through protease-activated receptors.
- While normally absent from blood-contacting cells, TF can be induced, and its dysregulation causes thrombosis.
Purpose of the Study:
- To review mechanisms regulating cell surface TF coagulant activity.
- To emphasize regulation independent of TF protein levels.
- To incorporate recent data and expert perspectives.
Main Methods:
- Literature review of TF regulation.
- Analysis of cell surface mechanisms affecting TF activity.
- Focus on post-translational modifications and membrane composition.
Main Results:
- TF activity is modulated by membrane composition (phospholipids, cholesterol).
- Thiol-dependent modifications and allosteric disulfide bonds impact TF function.
- Post-translational modifications offer additional regulatory layers for TF activity.
Conclusions:
- TF coagulant activity is finely tuned by multiple cell-surface mechanisms.
- Regulation independent of protein levels is critical for hemostatic balance.
- Understanding these mechanisms is key for managing thrombotic disorders.
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