PHILADELPHIA — Klaus Kaestner, PhD, professor of Genetics and postdoctoral fellow Dana Avrahami, PhD, from the Perelman School of Medicine, University of Pennsylvania, published a study this week in the Journal of Clinical Investigation, with colleague Benjamin Glaser, MD, from the Hadassah-Hebrew University Medical Center, Jerusalem, and colleagues. In this study, they were able to replicate human pancreatic beta cells – the cells in our body that produce the critical hormone insulin – in a mouse model in which donor cells were transplanted.