Sonja Schrepfer, M.D., Ph.D., Professor of Surgery, founded the Transplant and Stem Cell Immunobiology (TSI) Lab in 2009 in Germany. In 2016, she joined the faculty of the Department of Surgery at the University of California San Francisco. She is also Director of the TSI Lab at UCSF.

Dr. Schrepfer's research career has been dedicated to making fundamental discovers in stem cell immunology, transplant and cardiovascular immunobiology. Her lab currently works on immunobiological mechanisms of pluripotent stem cells (mouse and human). One project uses e.g. a combination of molecular/cellular biology, genomic/epigenomic profiling, tissue engineering, and molecular imaging technologies to better understand stem cell biology in vitro and in vivo. She has made significant contributions in the field of immunological barriers in regenerative medicine and in identifying novel immunobiological targets involved in cardiovascular diseases.