Intestinal Stem Cell (IMAGE) University of Pennsylvania School of Medicine Caption This is a stem cell (blue) from the intestinal crypt. Credit Norifumi Takeda, Raj Jain and Jon Epstein, Perelman School of Medicine, University of Pennsylvania 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.