“If we can identify how and when things go wrong at the cellular level, we may be able to interfere with this process or block it to prevent these diseases. It is an exciting time for stem cell biology, and now we can truly go forward and set the foundation for clinical breakthroughs. Stem cells are going to play a part in virtually all of the major medical breakthroughs of the twenty-first century.”

Ihor R. Lemischka, PhD
Director of the Black Family Stem Cell Institute and Lillian and Henry M.
Stratton Professorial Chair of Gene and Cell Medicine

The arrival of Ihor R. Lemischka, PhD, in 2007 signaled a major leap in stem cell research at Mount Sinai. Since his appointment as Director, the Black Family Stem Cell Institute has grown in both size and scope and now serves as a hub for both basic and disease-oriented research on embryonic and adult stem cells.

An internationally renowned stem cell biologist, Dr. Lemischka established his reputation as a pioneer in the field in the 1980s, when he became one of the first scientists to discover that a single blood-producing stem cell in bone marrow — known as a hematopoietic stem cell — could rebuild all blood cell types in a mouse whose blood cells had been destroyed. Since then, working with both adult and embryonic stem cells, he has studied stem cell behavior and activity and has obtained patents on gene products identified in isolated stem cells. His studies focus on stem cell mechanisms to determine how embryonic stem cells develop to form a variety of cell types, including muscle, nerve, and other tissues.

The Black Family Stem Cell Institute explores fundamental questions of human biology — questions even as basic as, “What makes a stem cell a stem cell?” Dr. Lemischka and his colleagues are investigating the process by which stem cells decide what type of cells they will become — known as cell fate decisions — and how these decisions are made. The Institute is also examining how stem cells, at all stages of development, communicate with neighboring cells. The goal is to characterize the stem cell’s decision-making process and regulatory network. Once this process is clarified, scientists hope to be able to manipulate stem cell decisions, reprogram these cellular processes, and develop novel therapeutics that provide the opportunity for more-targeted treatment and possibly even cell regeneration. Dr. Lemischka’s most recent research has found that it is possible to reprogram adult skin cells into cells that are very similar to embryonic stem cells.

In addition to relying on established approaches in experimenting with stem cells, the Black Family Stem Cell Institute plans to explore some newly available research tools and quantitative approaches. For example, work with the Experimental Therapeutics Institute and the Department of Pharmacology and Systems Therapeutics is underway to develop computational tools to model and understand the mechanisms by which stem cells control their differentiation decisions.

An active advocate, Dr. Lemischka has traveled the world educating the public about stem cell behavior and the potential within stem cell research. A member of the International Society for Stem Cell Research, Dr. Lemischka stands by the notion that scientific freedom is key to resolving some of the biggest mysteries in medicine and that a myriad of therapeutic opportunities lie in the decades ahead.

Dr. Lemischka came to Mount Sinai from Princeton University, where he spent 21 years at the forefront of stem cell research as a Professor of Molecular Biology. He earned his doctoral degree in the Center for Cancer Research at Massachusetts Institute of Technology and went on to become a postdoctoral research associate there. Afterward, Dr. Lemischka went to the Whitehead Institute for Biomedical Research in Cambridge, Massachusetts, where he completed an additional postdoctoral fellowship.