Influence of DT388–GM-CSF on sphingomyelin and ceramide metabolism, protein synthesis, and apoptosis in HL-60/VCR cells.
(A) Sphingomyelin and ceramide metabolism, and protein synthesis. Cells were exposed to 1.0 nM DT388–GM-CSF in medium containing [3H]palmitic acid for the times indicated. Radiolabeled sphingomyelin and ceramide were analyzed as detailed in “Materials and methods.” Protein synthesis was followed by [3H]leucine utilization as described in “Materials and methods,” and is represented as percent decrease in protein synthesis compared with rate in untreated control cells. (B) Apoptosis. HL-60/VCR cells were treated with 1.0 nM DT388–GM-CSF for the times shown and chromatin fragmentation was measured by the Cell Death Detection ELISA as described.
