Flow cytometric analysis of Bcl-x and Bcl-2 in CD34⁺ cells undergoing granulocyte or monocyte/macrophage differentiation. Cells were cultured in the presence of G-CSF or M-CSF and at the indicated time points differentiating cells were stained with mouse antihuman Bcl-x, hamster antihuman Bcl-2 (6C8) or irrelevant antibody as a background control (dotted lines) followed by biotin-conjugated goat antimouse or antihamster IgG and PE-conjugated streptavidin. All histograms are from a representative experiment (n = 3).