Immune Netw.  2008 Sep;8(3):75-81. 10.4110/in.2008.8.3.75.

Platelets Induce Proliferation of Human Umbilical Vein Endothelial Cells via CD154-CD40 Pathway Independently of VEGF

• Cho W
• Ko EM
• Cheon IS
• Jeoung DI
• Kim YM
• Choe J

• KMID: 2163196
• DOI: http://doi.org/10.4110/in.2008.8.3.75

Abstract

BACKGROUND: Platelets take part in repairing the lesions of endothelial damage. To understand the molecular mechanism of this process, we tested the hypothesis that CD154 expressed on activated platelets stimulates proliferation of human endothelial cells.
METHODS
The expression levels of CD154 and CD40 on platelets and endothelial cells, respectively, were measured by flow cytometry and confocal microscopy. Function-blocking monoclonal antibody against CD154 was developed after immunization with CD154- transfected L cells.
RESULTS
An anti-CD40 agonist antibody and soluble CD154 both induced significant proliferation of endothelial cells. In addition, a function-blocking anti-CD154 antibody inhibited the platelet-induced proliferation of endothelial cells, indicating that the CD154-CD40 pathway is involved in these cellular interactions. An anti-VEGF antibody failed to inhibit the proliferation. This, in addition to the fact that very small amounts of VEGF are released from platelets or endothelial cells, suggests that VEGF does not play an important role in the platelet-stimulated proliferation of endothelial cells.
CONCLUSION
Our results indicate that platelets induce proliferation of endothelial cells by CD154-CD40 interactions independently of VEGF.

Keyword

platelet; HUVEC; proliferation; CD40; CD154; VEGF

MeSH Terms

Blood Platelets
Endothelial Cells
Flow Cytometry
Human Umbilical Vein Endothelial Cells
Humans
Immunization
Microscopy, Confocal
Vascular Endothelial Growth Factor A
Vascular Endothelial Growth Factor A