FIG. 3.
Effect of specific caspase inhibitors on Stx1-induced apoptosis of THP-1 cells. Cells (2 × 106 cells/ml) were incubated with various caspase inhibitors (all at 40 μM) for 1 h and then treated with Stx1 (400 ng/ml) for 5 h. Cells were stained with Annexin V and PI and analyzed by flow cytometry. (A) Representative scatter plots showing percentages of cells staining Annexin V positive (lower right quadrants) or Annexin V/PI double positive (upper right quadrants). (B) Percentages of total apoptosis of THP-1 cells treated with specific caspase inhibitors and Stx1. Data shown are the means ± standard errors of the means from three independent experiments. *, a significant difference (P < 0.01) relative to Stx1 treatment.