Fig. 6
Effects of systemic sirolimus treatment on thymocyte caspase activity (Day 4). One representative from three triplicate experiments is shown. Mice received intraperitoneal DMSO (a) or sirolimus (b) on Days 0–3. On Day 4, thymic fragments were collected and incubated with the caspase-3 substrate Ac-DEVD-AMC with and without zVAD (pancaspase inhibitor) as described in “Methods” section. The tissue homogenates were separated on HPLC and analyzed by fluorescence for the released AMC moieties (reflecting intracellular caspase activity, R t = 3.44 min). The values of AMC peak areas (arbitrary unit ÷ 103 per mg) are shown. AMC peak areas decreased by ≥78 % in the presence of zVAD, confirming the cleavage was mediated mainly by caspases