Apoptosis as a Mechanism for Delayed Engraftment in Cryopreserved Peripheral Blood Stem Cell Transplants
High dose chemotherapy treatment for lymphoma is followed by the infusion of patients’ own bloodforming stem cells to restore the function of the bone marrow. Canada Blood Services provides critical support in processing and storing these essential stem cell products at very low temperatures. On occasion, the recovery of blood cells after the transplant is delayed, increasing the risk of infections and bleeding complications. In many cases, it is not known why there is delayed engraftment. Cells that undergo storage at low temperatures are exposed to special drugs, termed cryoprotectants that may cause harm to stem and progenitor cells and cause cellular death in some cases. The induction of cell death pathways, termed apoptosis, has not been systematically examined in blood stem cell products. By examining cells from actual cases of delayed engraftment and control samples, we hope to study the role of apoptosis in unexplained delayed engraftment.