In a first research of its kind, US researchers are addressing critical challenges for a successful cord blood banking. Low doses of stem cells that lead to longer recovery times, leaving patients more vulnerable to bleeding, infection and transplant failure.
The clinical trial randomized 71 patients with advanced leukemias or lymphomas into either a standard cord blood transplant, in which a patient receives blood stem cells from two umbilical cords, or to a second group that receives regular cells from one cord plus cells from a second cord that were exposed to growth factors in the lab to expand their number.
Patients with recurrent, high-risk acute myeloid leukemia, acute lymphocytic leukemia, chronic myelogenous leukemia, many types of lymphoma, aplastic anemia and other genetic and immunologic disorders require blood stem cell transplants to rebuild their blood supply after intense chemotherapy or as a therapeutic attack on their disease.
In all double-cord blood transplants, one of the two blood types ultimately becomes the patient’s sole blood supply. In half the patients who received expanded cord blood cells in the trial, de Lima noted, the expanded stem cells were predominant for the first 2-12 months after transplant, but by 14 months, the cells from the unexpanded cord become dominant.