Figure 3.

Cell binding activity of pK/DNA complex. HEK 293 cells were grown on 12-well dishes. Peptides and FITC-labelled-DNA were incubated together at the indicated ratios, at room temperature for 5 min in 1 ml of serum-free DMEM, and then added to cell monolayers. Cells were exposed to mixtures (2 μg of DNA) for 60 min at 37°C, 5% CO₂ (A–C). Cells exposed to mixtures containing 0.8 μg of TAT-pK and 0.2 μg of DNA for 60 min (D), 8μg of TAT-pK and 2 μg of DNA for 10 min (E) and 30 min (F), indicated ratios of TAT-pK and 2 μg of DNA for 60 min (G, H). In situ detection of TAT-pK/FITC-labelled-DNA complexes (I). Cells were exposed to mixtures containing 8 μg of TAT-pK and 2 μg of DNA for 2 h and FITC was detected with fluorescent microscopy as described under Materials and Methods.