Figure 3. Trigger of cell death by abrin-a A chain is independent of inhibition of protein synthesis.

HepG2 cells (1×10⁶/ml) were treated with 19.2 nM of either one of the immunoconjugates: F1G4-IT or F1G4-IT_R167L, or abrin (51.25 pM) for different time intervals. The cells were harvested, fixed with 70% ethanol at −20°C, stained with staining solution (20 µg/ml propidium iodide and 50 µg/ml RNase A in PBS) and analyzed by flow cytometry. The percentage of dead population was determined and plotted above control cells. Each bar represents the mean of at least three different experiments carried out with duplicate samples. **P<0.005.