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Updated: Jun 28, 2026
03:53
Extracellular Vesicle Tissue Factor Activity Assay
Published on: December 29, 2023
Plasmin enhances cell surface tissue factor activity in mesothelial and endothelial cells
1Biomedical Research, The University of Texas Health Science Center, Tyler, TX 75708, USA.
Journal of Thrombosis and Haemostasis : JTH
|November 6, 2008
Summary
Thrombin increases tissue factor (TF) in mesothelial cells via gene activation, while plasmin enhances TF activity by degrading TFPI. This clarifies protease roles in pleural injury responses.
Area of Science:
- Cell Biology
- Hemostasis and Thrombosis
- Protease-activated Signaling
Background:
- Mesothelial cells regulate local coagulation and fibrinolysis.
- Mechanisms of increased tissue factor (TF) expression in mesothelial cells post-injury are not fully understood.
Purpose of the Study:
- To determine if plasmin or thrombin induce TF expression in human pleural mesothelial cells (HMC).
- To elucidate the molecular mechanisms underlying protease-induced TF expression in HMC.
Main Methods:
- HMC and HUVEC exposed to plasmin or thrombin.
- TF activity measured via Factor Xa generation assay.
- TF antigen and mRNA levels analyzed by immunoblot and Northern blot.
Main Results:
- Both plasmin and thrombin increased HMC TF activity 3-4 fold.
- Thrombin induced de novo TF synthesis; plasmin did not.
- Plasmin inactivated cell-associated TFPI through proteolysis.
Conclusions:
- Thrombin up-regulates TF activity in HMC via transcriptional activation.
- Plasmin increases TF activity by proteolytically inactivating cell-associated TFPI.
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