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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
Human peripheral blood endothelial progenitor cells synthesize and express functionally active tissue factor
Rossella Di Stefano1, Maria Chiara Barsotti, Chiara Armani
1Cardiovascular Research Laboratory, Cardiac, Thoracic and Vascular Department, University of Pisa, Pisa, Italy. r.distefano@ao-pisa.toscana.it
Thrombosis Research
|January 9, 2009
Summary
Endothelial progenitor cells can synthesize tissue factor when stimulated by lipopolysaccharide. This finding suggests a role for tissue factor in cell-related neovascularization and thrombosis.
Area of Science:
- Cell Biology
- Hematology
- Vascular Biology
Background:
- Endothelial progenitor cells (EPCs) are crucial for repairing damaged vasculature and promoting revascularization in ischemic tissues.
- Tissue factor (TF) is a key procoagulant protein with known roles in angiogenesis.
Purpose of the Study:
- To investigate whether EPCs synthesize tissue factor.
- To determine the conditions under which TF expression is induced in EPCs.
Main Methods:
- EPCs were isolated from peripheral blood mononuclear cells and cultured.
- Procoagulant activity was measured using a clotting assay.
- TF mRNA expression was confirmed via RT-PCR.
Main Results:
- EPCs did not exhibit procoagulant activity at baseline.
- Lipopolysaccharide (LPS) induced dose-dependent TF expression in EPCs, with significant effects at 100 ng/mL.
- TF expression kinetics in EPCs mirrored that of human umbilical vein endothelial cells, peaking within 4 hours.
- Inhibition studies confirmed the induced activity as TF, and protein synthesis inhibitors blocked its expression.
Conclusions:
- EPCs can be induced to synthesize tissue factor by LPS stimulation.
- The TF produced by EPCs may play a role in thrombotic events and neovascularization processes.
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