Stem Cells (IMAGE) Massachusetts Institute of Technology Caption This image shows human embryonic stem cells grown on a synthetic surface developed by MIT researchers. The cells at top (blue) are stained to reveal their nuclei, while the cells in the middle and bottom are stained for proteins that are known to be present when cells are pluripotent. Green cells are stained for Oct4 (using green fluorescent protein) and red cells are stained for SSEA-4. Credit Ying Mei, Krishanu Saha, Robert Langer, Rudolf Jaenisch, and Daniel G. Anderson Usage Restrictions With proper caption and credit 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.