Effect of GM-CSF on procaspase 3 protein levels in OCI/AML3, Mo7e, and TF-1 cells. (A) Growth factor–deprived OCI/AML3 cells were incubated in the absence of GM-CSF and in the presence of increasing concentrations of GM-CSF. Procaspase 3 protein was detected by Western immunoblotting. Representative data from 3 different experiments are shown. (B-C) Effect of GM-CSF on procaspase 3 protein levels in Mo7e (B) and TF-1 (C) cells. Growth factor–deprived cells were incubated in the absence of GM-CSF and in the presence of 0.025 μg/mL GM-CSF. Procaspase 3 protein was detected at different time points by Western immunoblotting. A band of β-actin, demonstrating equal protein loading, is presented as loading control. Representative data from 3 different experiments are shown.