Use of Hemapheresis-Derived Hemopoietic Stem Cells for Transplantation in Malignant Lymphohemopoietic Disorders

The usual source of hemopoietic stem cells for transplantation is the bone marrow. However, evidence in rodents, canines and non-human primates indicates that stem cells with marrow repopulating ability also circulate in the peripheral blood [1–4]. To use the circulating blood as the primary source of stem cells to repopulate an aplastic bone marrow is a concept which reflects the physicological 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].