Growth and differentiation of v-Myc expressing U-937-myc-6 and parental U-937-GTB cells. Cells were induced by TPA, IFN-γ, or TPA + IFN-γ and analyzed at the indicated time points. (A) ³H-TdR incorporation. Cells were labeled with 10 μCi of ³H-TdR for 1 hour. (B) CD11a, (C) CD11b, (D) CD4, (E) CD11c, and (F) FcγRI expression. The surface antigen expression was measured by fluorescence-activated cell sorter analysis by using specific antibodies.