“Our stem cell plan has an individual focus on the patient. We’re going to make stem cells from a child with a genetic disease, repair those gene defects, coax their cells to become the tissue or the organ affected by the disease and give them back healthy tissues. By recreating their disease in a dish, we can predict with much greater accuracy whether a drug will actually work." – George Q. Daley, MD, PhD, Director of Stem Cell Transplantation Program, Children's Hospital Boston
Stem cells have long been used in the treatment and cure of various diseases of the blood, including immunologic disorders. For the past 40 years, clinicians have used stem cell or bone marrow transplantation in patients with acute and chronic leukemia, lymphoma, severe combined immunodeficiency syndrome, sickle-cell disease, bone marrow failure syndromes such as severe aplastic anemia, and other disorders. The Stem Cell Transplantation Program at Boston Children’s Hospital, established in the 1970’s, operates in partnership with Dana Farber Cancer Institute. It is one of the largest and most active pediatric transplantation programs in the United States: more than 70 pediatric stem cell transplants were completed last year alone.
Bone marrow transplant is an amazing, life-saving and proven option for many patients. However, in some instances, matching donors cannot be found; and there can be a risk in bone marrow transplant of rejection of the donor marrow. George Q. Daley, Director of the Stem Cell Transplantation Program at Children’s, sees these problems in the clinic; his laboratory and others at Children’s are working on ways to overcome those issues.
Dr. Daley’s research includes using gene therapy to fix genetic defects and getting corrected cells to make blood stem cells that match the donor genetically, using stem cell treatments to correct hemoglobin disorders like sickle cell anemia in mouse models, and using embryonic stem cells and induced pluripotent stem cells to better understand such diseases as Fanconi anemia.
Moving theory to clinical practice, hematologist Leonard Zon, MD, Director of the Stem Cell Program at Children’s, has taken a discovery in zebrafish — that the drug, PGE2, can boost numbers of blood stem cells — which has great potential for helping patients battling certain types of cancer. His work has led to a new clinical trial for patients undergoing leukemia or lymphoma treatment.
Children’s scientists and clinicians now hope to repeat these successes in other diseases, ranging from cystic fibrosis to neurologic disorders such as Fragile X syndrome, which the Daley Lab has already modeled in pluripotent stem cells. In 2008, Children’s became the first center to establish a line of iPS cells from patients with specific diseases. There are now dozens of diseases modeled in iPS cells, raising hopes that better understanding of these conditions’ origins will soon lead to new treatment approaches.
Many Affiliate Members of the Stem Cell Program are also pursuing tissue-engineering approaches using adult stem cells. These range from using stem cells from amniotic fluid to fashion tissues to repair birth defects to using bone-marrow stem cells to help repair lung injuries in newborns. These approaches have been tested in animal models and some are moving closer to clinical trial.
Significant and exciting progress is being made. However, there are no short-cuts in sound and responsible science. While an increasing number of clinics around the world claim that they can already provide stem cell “cures” for a variety of diseases such as Parkinson disease, neurological diseases and muscular dystrophy, there is little objective scientific evidence to support these claims. Without objective third party review and outside of a responsible regulatory environment focused on patient safety, many of these treatments may in fact pose significant risks. Boston Children’s Hospital joins the International Society for Stem Cell Research in cautioning patients to carefully assess the credibility of these claims of “cures”.