CTL-induced apoptosis is inhibited by the PTP inhibitor CsA and the ROS scavenger D1417. (A) CTL-induced tritium release in target cells overexpressing Bcl-2 is dependent on the PTP. Jneo cells (□) and JBcl-2 cells (■) were preloaded with 3H-thymidine and incubated for 2 hours with CTLs (E/T ratio = 2:1) or grB/AD in the presence or absence of 100 μM CsA and 5 μM verapamil. The percentage of tritium release, which is an indication of DNA fragmentation, was determined as is outlined in “Apoptosis detection systems.” The numbers indicate the average of 3 independent experiments done in triplicate, with the corresponding standard deviation. (B) CTL-induced tritium release in target cells overexpressing Bcl-2 is dependent on the production of ROS. Jneo cells (□) and JBcl-2 cells (■) were preloaded with 3H-thymidine and incubated for 2 hours with CTLs (E/T ratio = 2:1) or grB/AD in the presence or absence of 1 mM or 3.5 mM D1417, a ROS scavenger. The percentage of tritium release, which is an indication of DNA fragmentation, was determined as outlined in “Apoptosis detection systems.” The numbers indicate the average of 3 independent experiments done in triplicate, with the corresponding standard deviation.
