Leonardo V. Riella, M.D. Ph.D. is the Harold and Ellen Danser Endowed Chair in Transplant Surgery at Harvard Medical School and the Medical Director of Kidney Transplantation at the Massachusetts General Hospital. Dr. Riella’s research is focused on understanding the mechanisms of immune regulation and on developing novel therapies to promote immune tolerance. His lab is also tackling the organ transplant shortage head-on by pioneering two extraordinary paths: bioengineering kidneys from human stem cells and turning to gene-modified pigs as potential kidney donors. These innovative approaches could drastically increase the availability of organs and transform the transplant landscape.