Vascular endothelial growth factor (VEGF), also known as vascular permeability factor (VPF) and VEGF-A, and is a member of the platelet-derived growth factor (PDGF)/vascular endothelial growth factor (VEGF) family and encodes a protein that is often found as a disulfide linked homodimer. This protein is a glycosylated mitogen that specifically acts on endothelial cells and has various effects, including mediating increased vascular permeability, inducing angiogenesis, vasculogenesis and endothelial cell growth, promoting cell migration, and inhibiting apoptosis. Alternatively spliced transcript variants, encoding either freely secreted or cell-associated isoforms, have been characterized. Alternatively spliced isoforms of 121,145,165,183,189 and 206 amino acids in length are expressed in humans. Mature human VEGF189 shares 88% aa sequence identity with mouse VEGF188. VEGF189 binds to heparan sulfate both on the cell surface and in the extracellular matrix (ECM) where it retains bioactivit. Furthermore, VEGF189 interacts with various receptors including VEGF R1, VEGF R2, Neuropilin-1, and Integrins aVb3, aVb5, a3b1, and a5b1.