Replicating Human Beta-Cells (image) University of Pennsylvania School of Medicine Caption In cells where p57 was successfully inhibited, beta-cells could undergo DNA replication. Pink: nucleus that has undergone DNA replication. Green: Insulin. Blue: Nuclei counterstained for DNA. White: p57. Credit Klaus Kaestner, Ph.D., Perelman School of Medicine, University of Pennsylvania; JCI Usage Restrictions None 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.