[Different effects of cytostatics on cell kinetics of normal and leukemic human bone marrow in vitro]

The kinetics of the erythropoietic and of the granulocytopoietic pool of normal und leukemic human bone marrow cells were investigated in vitro under the influence of 23 cytostatic drugs. Clot cultures were evaluated up to 72 hours by differential and mitotic counting in smears stained according to Pappenheim. Based on mitotic index, caryological curve and percentage of proliferative cells different patterns of proliferation were observed: spindle poisons enhanced the mitotic index, all other investigated cytostatic drugs diminished it, but in a different degree the one of the erythroblasts, of the granuloblasts and of the leukemic blasts. The decrease of the percentage of proliferative precursors did not always correlate with the decrease of the mitotic index, because sometimes an ineffective granulocytopoiesis arised or leukemic blasts entered the Go-phase of the cell cycle. 1-asparaginase was the only drug which increased erythroblasts. Chloramphenicol was the only out of 18 drugs tested on leukemic bone marrow that decreased only the leukemic proliferation and had no influence on the normal one.