In a study published in Nature, researchers describe a new strategy to make stem cell transplants safer by replacing chemotherapy-based treatment with a more targeted approach. Instead of using toxic agents that damage DNA throughout the body, they use antibodies that recognize specific markers on blood-forming stem cells. These antibodies can help clear the patient’s existing stem cells from the bone marrow in a more selective, less toxic way.

An antibody normally cannot distinguish between the patient’s original stem cells and the infused therapeutic stem cells from the treatment. If the antibody remains in the body, it may also attack the transplanted cells, preventing them from integrating. Researcher Pietro Genovese, Ph.D., of the Dana-Farber/Boston Children’s Cancer and Blood Disorders Center, and his team have solved this problem by giving the therapeutic stem cells a form of molecular protection.