Abstract
Alterations in bone marrow CFU-C and CFU-E in various hematological disorders were studied to clarify the pathogenesis of these disorders from the point of view of hematopoietic stem cells. Emphasis was put on a series of anemia caused by the disturbance of red cell production, polycythemia and leukemias. In aplastic anemias. CFU-C and CFU-E were decreased invariably and the presence of mononuclear cells which are suppressive both to CFU-C and CFU-E was demonstrated in peripheral blood or bone marrow of the patients. It was demonstrated that monocytes and macrophages were playing an important role in this suppression. In sideroblastic anemia, presence of 2 clones of stem cells, the one normal clone forming normal erythroblast colony and the other abnormal clone which develops to the ringed sideroblast in vitro and can not form the erythroblast colony, was demonstrated. By cultivating the peripheral blood of a patient with acute non-lymphocytic leukemia, we could make a leukemia blast colony in vitro. This leukemia colony was consisted of leukemic blasts and the kinetic study on leukemia colony formation showed that each colony was developed from each leukemic stem cell. In chronic myelogenous leukemia, both CFU-C and CFU-E were increased in numbers. CFU-E in chronic myelogenous leukemia was dependent on the erythropoietin.
