Rapa-induced apoptosis is partially blocked by inhibition of caspase activity.

Immature mo-DCs were cultured in RPMI–10% FCS supplemented with IL-4 and GM-CSF in the absence or presence of 10⁻⁸ or 10⁻⁷ M Rapa for 48 hours. Before addition of Rapa, the cells were preincubated with ZVAD-fmk (5 × 10⁻⁵ M) or its solvent, DMSO. Apoptosis was detected by flow cytometry using annexin V/PI staining. The percentage of apoptosis demonstrates the percentage of annexin V⁺ PI⁻ cells. Data shown are the mean ± SD of duplicate cultures. The results are representative of 5 independent experiments.