Enhancement of granulocytic colony formation by deletion of phagocytic cells in the bone marrow of patients with idiopathic aplastic anemia

To study the pathogenesis of aplastic anemia, phagocytic cells from the bone marrow of patients with aplastic anemia were investigated. From 10 of 10 patients with this disease the concentrations of CFUc in the bone marrow cells significantly increased after the removal of phagocytic cells. On the other hand, in bone marrow from only 4 of 27 controls, 22 non-aplastic anemia patients and 5 normal volunteers, the concentration of CFUc increased after the same treatment. From these findings, it may be inferred that phagocytic cells from the bone marrow of patients with aplastic anemia suppress proliferation and differentiation of granulocytic progenitor cells, and that this phenomenon is related to the development of this disease.