Stimulation of phosphoinositol turnover and protein kinase C activation by granulocyte macrophage colony stimulating factor in HL-60 cells

Phosphoinositol turnover, diacylglycerol generation, protein kinase C (PK-C) activity, and intracellular cyclic nucleotides were studied in an established human leukemia cell line, HL-60, in response to one of the hematopoietic cytokines, granulocyte-macrophage colony-stimulating factor (GM-CSF). Continuous exposure of HL-60 cells to GM-CSF induced the cell differentiation that was evaluated by the nitroblue tetrazolium (NBT) reducing activity. GM-CSF also exhibited a proliferative effect on HL-60 cells. GM-CSF at 1 nmol/L, an optimal concentration for cell growth and cell differentiation, induced significant changes in the intracellular inositoltriphos-HE HEMATOPOIETIC stem cells are thought to be T regulated by a group of cytokines, such as multi-colony-stimulating factor interleukin-3 (IL-3), macrophage colony-stimulating factor (M-CSF), granulocyte-CSF (G-CSF), and granulocyte-macrophage-CSF (GM-CSF) in their sur