Determination of caspase activity within CD4+ T lymphocytes through chemical chromatography

PBS was used to wash the collected CD4⁺ T lymphocytes (1×10⁶) twice, after which the supernatant was discarded, 250 μl precooled lysis buffer was added, and the mixture was later placed in an ice bath for 10 min. The homogenate was centrifuged at 1000 rpm for 5 min, the supernatant was transferred to an EP tube, and the caspase activity was determined in the 96-well plate. The reaction system consisted of 100 μg protein, 50 μl reactive solution, and 5 μl caspase colorimetry for substrate. The homogenate was incubated for 2 h at 37°C in the dark, and the results were measured using a microplate spectrophotometer.