CEBPA^sil leukemia cells are resistant to myeloid growth. Tritiated thymidine incorporation experiment of 3 CEBPA^sil and 7 CEBPA^mut leukemia samples. Response of leukemia cells to IL-3, GM-CSF, and G-CSF is shown relative to irradiated nonstimulated cells (ie, stimulation index), based on the mean of 3 measurements.