Blood and Bone Marrow Hematopoietic Stem Cells for Transplantation: A Comparative Review

Classical bone marrow transplantation collects bone marrow from a normal individual. This is infused into a patient rendered aplastic by high-dose chemoradiotherapy. Shortcomings include a limited donor pool and morbidity and mortality from graft-vs-host and graft rejection phenomena. Autologous marrow transplantation, in which the marrow of the patient to be transplanted is harvested, cryopreserved, and stored until needed, is not so constrained. Although marrow cannot be collected from some individuals due to hypocellularity, fibrosis, or infiltration with malignant disease, the presence of peripheral blood stem cells in the circulation allows these individuals to be treated with autologous transplantation therapy. It has been postulated that these hematopoietic progenitors have advantages over bone marrow collected stem cells, including safer and less expensive collections and accelerated rates of hematopoietic recovery following high-dose therapy and stem cell reinfusion.