Lack of effects of indomethacin and NDGA on the stimulation of surface expression of CD64 induced by IFN-γ in HL-60 cells. HL-60 cells were incubated for 5 days with IFN-γ (2,000 U/mL), indomethacin (50 μmol/L), NDGA (50 μmol/L), or the combination of IFN-γ (2,000 U/mL) and indomethacin (50 μmol/L) and the combination of IFN-γ (2,000 U/mL) and NDGA (50 μmol/L). Expression of CD64 was determined by flow cytometry. The data (means ± SD) represent the percentage of cells staining positive for the respective antigen obtained from six independent experiments. * Significantly different (P < .05, Student's t-test) from controls.