Donald B. Kohn, M.D., studies the biology of blood stem cells, which are located in the bone marrow and have two important properties: they can duplicate themselves and they can create all types of blood cells. Over the course of 30 years of research, Kohn has developed new clinical methods to treat genetic blood diseases using blood stem cells that have been modified to remove genetic mutations. Kohn’s blood stem cell gene therapy method collects some of a patient’s own blood stem cells and either adds a good copy of the defective gene or fixes the broken genes to eliminate disease-causing mutations. The patient then receives a transplant of their own corrected stem cells, which will ideally create an ongoing supply of healthy blood cells. Importantly, this method eliminates the risk of rejection associated with receiving a bone marrow transplant from a different person, meaning the patient doesn’t have to take a lifelong supply of anti-rejection drugs. Kohn’s clinical trials for adenosine deaminase-deficient severe combined immunodeficiency (also known as ADA-SCID or bubble baby disease), a condition where babies are born without an immune system and often don’t survive past the first two years of life, have cured more than 40 babies to date. Babies with the condition and their families have traveled to UCLA for this life-saving treatment from as far away as Lebanon and a new company was formed in 2016 to further develop the therapy and make it available at other centers and to more patients. Kohn is now applying similar blood stem cell gene therapy techniques in clinical trials for two other diseases. One of these diseases is X-linked chronic granulomatous disease, a rare inherited immunodeficiency disorder that prevents white blood cells from effectively killing foreign invaders such as bacteria, fungi or other microorganisms. If untreated, patients often succumb to chronic granulomatous disease within the first decades of life. The second disease is sickle cell disease, the most common inherited blood disorder in the United States. This disease causes abnormal ‘sickle-shaped’ red blood cells that block small blood vessels and do not provide the appropriate amount of oxygen to the body, resulting in debilitating pain and organ damage. Kohn’s clinical trial seeks to overcome or repair the genetic mutation that causes this devastating disease, which impacts millions worldwide. Kohn earned his bachelor’s and master’s degrees from the University of Illinois, Champaign-Urbana and his medical degree from the University of Wisconsin School Of Medicine. He completed a pediatric internship and residency in Wisconsin followed by a medical staff fellowship in the Lymphoid Malignancies Branch (formerly the Metabolism Branch) of the National Cancer Institute. Kohn began working on gene therapy as a fellow at the National Institutes of Health in 1985 and then began practicing as a pediatric bone marrow transplant physician at Children’s Hospital Los Angeles in 1987. While practicing at Children’s Hospital Los Angeles, he started his own lab focused on stem cell research and has continued this work, advancing new therapies from the lab to the clinic.
“All of the children with SCID that I have treated in these stem cell clinical trials would have died in a year or less without this gene therapy, instead they are all thriving with fully functioning immune systems.”
- UCLA Researchers Announce Gene Therapy Cure for 18 ‘Bubble Baby’ Patien