Endothelial Cells (IMAGE) University of Illinois Chicago Caption Left: Endothelial cells derived from stem cells treated with growth factors alone don't form blood vessels. Right: Endothelial cells derived from stem cells treated with growth factors and glutamine withdrawal form organized blood vessels. Credit Image credit: Jalees Rehman. Usage Restrictions None License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.