Is blood a better source of allogeneic hematopoietic stem cells for use after radiation accidents?
Peripheral blood and cord blood are increasingly used as sources of hematopoietic stem cells. They offer several advantages over bone marrow-derived stem cell grafts and are expected to replace bone marrow transplantation for treatment of malignant hematological disorders and solid tumors. Since the benefit of bone marrow transplantation for treatment of victims of radiation accidents has been seriously questioned, it is reasonable to examine if these alternative stem cell sources may change future strategies. Cord blood is attractive since it is an immediately available and fully characterized allogeneic stem cell source. However, experience with transplants in children suggests that recovery times are too long to benefit a victim of a radiation accident. Because of their potential to rapidly restore hematopoiesis, peripheral blood stem cells may currently be the best stem cell source for a patient who is expected to die from the consequences of prolonged pancytopenia (and not from damage of nonhematopoietic tissue). However, before getting accepted as the optimal stem cell source, the risk of acute and chronic GVHD must be confirmed to be low and unrelated donors must be shown to accept the potential risk of treatment with mobilizing agents. Future strategies should aim at developing methods of transiently rather than permanently engrafting allogeneic stem cells, since essentially all patients exposed to high doses of irradiation are expected to recover autologous marrow function.
Frickhofen
N
N
Department of Medicine III, University of Ulm, Germany.
Körbling
M
M
Fliedner
T M
TM
D001773:Blood Cells / Q000637:transplantation*; D001854:Bone Marrow Cells; D001855:Bone Marrow Diseases / Q000209:etiology / Q000628:therapy*; D002648:Child; D005312:Fetal Blood / Q000166:cytology; D005544:Forecasting; D030342:Genetic Diseases, Inborn / Q000628:therapy; D006086:Graft vs Host Disease / Q000517:prevention & control; D018380:Hematopoietic Stem Cell Transplantation; D006801:Humans; D007937:Leukapheresis / Q000379:methods; D011832:Radiation Injuries / Q000209:etiology / Q000628:therapy*; D018788:Radioactive Hazard Release; D011878:Radiotherapy / Q000009:adverse effects*