Role of proliferation in endothelial cell monolayer formation

In the present study, the rates of human coronary artery endothelial cell (HCAEC) monolayer formation on a tissue engineered blood vessel wall model (TEWM) and collagen coated glass are evaluated in both static and fluid flow conditions. The role of proliferation in monolayer formation was investigated by determining the percentage of cells proliferating through BrdU incorporation. The role of proliferation was further investigated by evaluating monolayer formation and cell proliferation after exposure to mitomycin, a proliferation inhibiting drug. Finally, stimulation of proliferation on the TEWM was attempted by incorporating bFGF into the model. These experiments showed that the rate of monolayer formation was significantly reduced on the TEWM when compared to formation on glass in static culture. The reduced rate of monolayer formation correlated to fewer proliferating HCAEC on the TEWM and on the glass when exposed to shear stress. Exposure to mitomycin caused a decrease in both monolayer formation and proliferating cells in a dose dependent manner. The addition of bFGF showed a significant increase in monolayer formation on the TEWM. These experiments indicate that stimulation of proliferation, possibly through incorporation of bFGF, may be a potential method of promoting the formation of monolayers on tissue engineered vascular grafts.