Induction by recombinant human granulocyte colony-stimulating factor of differentiation of mouse myeloid leukemic M1 cells.

The effect of recombinant human granulocyte colony-stimulating factor (G-CSF) on induction of differentiation of mouse myeloid leukemic M1 cells was examined. Purified G-CSF caused dose-dependent induction of phagocytic activity and lysozyme activity in M1 cells. Its half-maximally effective concentration was 10 ng/ml. On treatment of M1 cells with G-CSF (100 ng/ml) for 4 days, 30-50% of the cells differentiated morphologically into macrophage cells; 30-40% of the cells were blast cells and 20-30% of the cells were forms intermediate between blastic cells and mature macrophages.