Transplantation of hemapheresis-derived hemopoietic stem cells: A new concept in the treatment of patients with malignant lymphohemopoietic disorders

Abstract

The usual source of hemopoietic stem cells for transplantation is the bone marrow. However, evidence in rodents, canines, and nonhuman primates indicates that stem cells with marrow repopulating ability also circulate in the peripheral blood. l-4 To use the circulating blood as the primary source of stem cells to repopulate an aplastic bone marrow is a concept that reflects the physiological pattern in which fetal hemopoiesis develops. The fetal bone marrow becomes a site of hemopoiesis after pluripotent hemopoietic stem cells immigrate into its stromal matrix via the circulating blood. Thus, transfusing blood-derived stem cells in adults may be considered to repeat the prenatal seeding of hemopoiesis into the bone marrow. 5.6 In man, the repopulating ability of circulating stem cells is less well established. Goldman et al. 7 were the first to show that blood-derived hemopoietic stem cells can reestablish hemopoietic function after myeloablative treatment for blast crisis in chronic myelogenous leukemia (CML). However, in these patients most stem cells collected and eventually