The expression and production of vascular endothelial growth factor in oral mucosa equivalents

Angiogenesis is anticipated during wound healing. Vascular endothelial growth factor (VEGF) is a potent direct angiogenic factor that stimulates endothelial cell migration and proliferation in vitro and angiogenesis in vivo. Ex vivo produced oral mucosa equivalent (EVPOME) grafts have been reported to promote re-vascularization in the underlying tissue after grafting. The aim of this study was to evaluating the following: VEGF mRNA and its protein expression in EVPOME grafts, the protein levels in conditioned media produced by EVPOMEs, and the ability of VEGF to stimulate the growth of microvascular endothelial cells. VEGF mRNA expression and immunoreaction were found in basal and suprabasal layers. VEGF secreted by EVPOME was detected throughout the period of manufacture of the grafts, and became elevated for the first week at an air-liquid interface. Both EVPOME-conditioned media and a medium containing 10ng/mL recombinant human VEGF induced endothelial cell proliferation, while neutralization of VEGF by an antibody blocked cell growth. These results suggest that VEGF secreted by EVPOME grafts might assist initial vascularization after grafting, which is critical to subsequent graft survival.