TABLE 2.
Levels of apoptosis and necrosis in VT1 or bacterium-treated HEp-2 cells (determined by electron microscopy)a
| Treatment | Mean % ± SD
|
|
|---|---|---|
| Apoptotic cells | Necrotic cells | |
| None | 0.85 ± 0.69 | 3.9 ± 1.0 |
| VT 1 (12.5 ng/ml overnight) | 15.8 ± 3.6 | 15.2 ± 2.8 |
| EPEC E2348/69 (5 h) | 13.5 ± 2.3 | 13.4 ± 1.4 |
| EHEC 84-289 (5 h) | 12.0 ± 1.9 | 15.0 ± 3.5 |
| EHEC 85-170 (5 h) | 10.7 ± 0 | 12.3 ± 2.5 |
| HB101 (5 h) | 6.2 ± 1.2 | 7.3 ± 0.7 |
a
Percentages based on a count of at least 100 cells and experiments were determined two to five times. Apoptosis was evidenced by nuclear condensation, membrane blebbing, and decreased cell volume. Necrosis was evidenced by swollen cell morphology, nuclear membrane disintegration, and plasma membrane breaks.