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Updated: Jun 26, 2026
10:08
Flow Cytometry Analysis of Tissue Factor Expression in Human Platelets
Published on: November 22, 2024
Melagatran prevents tissue factor expression in human platelet-monocyte heterotypic complexes
A Belliard1, G Mauco, M L Bonnet
1Inserm U927, Poitiers, F-86021, France.
Cellular and Molecular Biology (Noisy-Le-Grand, France)
|January 20, 2009
Summary
Melagatran, a direct antithrombin drug, significantly reduced procoagulant Tissue Factor (TF) expression in platelet/monocyte heterotypic complexes (PMHC). This suggests melagatran may prevent TF-driven thrombin generation.
Area of Science:
- Hematology
- Pharmacology
- Thrombosis Research
Background:
- Platelets and monocytes form complexes (PMHC) that induce Tissue Factor (TF) expression.
- TF expression by PMHC promotes thrombin generation and thrombosis.
Purpose of the Study:
- To investigate the preventive effect of melagatran on TF expression in PMHC.
- To determine if melagatran affects platelet activation within PMHC.
Main Methods:
- Human venous blood samples were collected with heparin or heparin and melagatran.
- Flow cytometry and Western blot analyzed TF and P-selectin expression on PMHC.
- TF protein expression in monocytes was specifically examined.
Main Results:
- Melagatran significantly reduced TF-positive PMHC percentage (2.6% vs. 5.9%).
- Melagatran increased P-selectin expression on PMHC, indicating enhanced platelet activation.
- Western blot suggested melagatran targeted a 54kD TF form in monocytes.
Conclusions:
- Melagatran effectively decreases TF expression in PMHC.
- The mechanism involves targeting TF in monocytes, not reducing platelet activation.
- Melagatran shows potential in preventing TF-driven thrombin generation.
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