Primary vascular plexus originate from angioblasts through a process called vasculogenesis. The precise role of basic fibroblast growth factor (bFGF) and the vascular endothelial growth factor (VEGF) are both suggested as key regulators in vasculogenesis is still unclear. This crucial aspect was investigated by using time lapse observation of in vitro generated embryonic stem (ES) cell-derived endothelial structures which were recognizable by using the platelet cell adhesion molecule (PECAM-1) driven endothelial-specific expression of the live reporter gene enhanced green fluorescent protein (EGFP). In serum free conditions VEGF led to improved survival of angioblasts and to the formation of primitive endothelial tubes whereas bFGF alone increased their survival. Our study suggests that the complex process of vasculogenesis can be driven by VEGF alone but not by bFGF.
Copyright 2002 S. Karger AG, Basel