The bcl-2 protein content of TF-1 transfectants. Cell lysates were prepared from vector or PKC isoform overexpressing cells grown in the presence of IL-3 (+IL-3) or deprived of IL-3 (-IL-3) for 40 hours. Proteins in cell lysates were separated by electrophoresis in 16% SDS polyacrylamide gel and analyzed by immunoblotting using an antihuman bcl-2 murine monoclonal antibody obtained from Santa Cruz Biotechnology Inc (Santa Cruz, CA). Similar results were obtained in three different experiments.