FIG. 3.

CPE-induced DNA cleavage in CaCo-2 cells treated with 1 μg of CPE per ml. (A) Confluent CaCo-2 cells were pretreated for 2 h at 37°C with HBSS that contained or did not contain either the broad-spectrum caspase inhibitor Z-VAD-FMK or the oncosis inhibitor glycine. Those cultures were then treated for 60 min at 37°C in HBSS with or without 1 μg of CPE per ml, along with the same inhibitor (if any) used during pretreatment. After CPE treatment, DNA was extracted from each sample and run on a 2% agarose gel, followed by staining with ethidium bromide. CaCo-2 cells treated for 8 h at 37°C with either 2 μM staurosporine (Staurosp.) or 5 μM ionomycin (IONO) served as positive controls for apoptosis and oncosis, respectively. Control,CaCo-2 cells treated only with HBSS (no CPE). The arrows indicate the migration of DNA size markers. (B) Confluent CaCo-2 cells were pretreated for 2 h at 37°C with HBSS that contained or did not contain a specified caspase inhibitor and then treated for 60 min at 37°C in HBSS with or without 1 μg of CPE per ml, along with the same inhibitor (if any) used during pretreatment. After CPE treatment, DNA was extracted from each sample and run on a 2% agarose gel, followed by staining with ethidium bromide. Control, depicts CaCo-2 cells treated only with HBSS (no CPE). The arrows indicate the migration of DNA size markers.