Figure 5

The effect of 1 μg ml⁻¹ brefeldin A (BFA), 100 μM chloroquine (CQ) and 100 μM histidine (His) on endosomal release of a TP ODN (FL-4PA). Note that the suggested concentration of BFA is 10 μg ml⁻¹ for endosomal release. In the research reported here, this concentration caused significant toxicity even after a short treatment. Thus, a lower and less toxic 1 μg ml⁻¹ concentration was used for this experiment. Passive transfection was performed using 3 μM TP ODN FL-4PA for 24 h followed by washing. Cells were then incubated with BFA, CQ and His, respectively. Three-dimensional microscopy was taken at 0.5 μm per step for 30 steps. Fl-4PA: 5′-FL-T_PepAGTAAAC_PepACATGA_PepATGTGCTGCT_PepAA-3′. PepA, AcHN-Lys(N₃)-Lys-Lys-Arg-Gly-NH₂.