Human Vascular System in Mice (2 of 2) (IMAGE) Helmholtz Association Caption The three-dimensional analysis of blood vessels formed shows that growth factors such as fibroblast growth factor-2 effectively promote the coating of the newly formed blood vessels (stained green) with smooth muscle cells (stained red). Image was taken with a confocal microscope. Credit Professor Hellmut Augustin, Joint Research Division "Vascular Biology" of the Mannheim Medical Faculty of the University of Heidelberg and the German Cancer Research Center Usage Restrictions Use credit line 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.