HUVECs were infected with Lentiviral particles expressing human VEGFR2 specific shRNAs and GFP @ passage 1. Puromycin resistant HUVECs-shRNAVR2-GFP cells were selected and shipped in frozen vials (cells are provided @ passage 3). Endothelial Growth Medium is recommended for cell culture and these cells have a minimum of 18 population doubling levels when cultured following the protocols described below).