Figure 4
Cellular internalization of the DMAE-SS-PRX/β-gal complexes.
(A-D) CLSM images of HeLa cells after 24 h incubation with FITC-β-gal (A) cell-penetrating peptide-based Xfect/FITC-β-gal (B) cleavable DMAE-SS-PRX/FITC-β-gal (N/C 2) (C) and non-cleavable DMAE-PRX/FITC-β-gal (N/C 2) (D) (scale bars: 20 μm). The nuclei and the late endosomes/lysosomes were visualized with Hoechst 33342 (blue) and LysoTracker Red (red), respectively. (E) Mean fluorescence intensities of HeLa cells after 24 h incubation with FITC-β-gal, Xfect/FITC-β-gal, cleavable DMAE-SS-PRX/FITC-β-gal (N/C 2) and non-cleavable DMAE-PRX/FITC-β-gal (N/C 2) as determined by flow cytometry. In these experiments, the initial concentration of FITC-β-gal in the medium was adjusted to 20 nM. Data are expressed as the means ± SD of triplicate experiments (*p < 0.05, **p < 0.001, NS indicates not significant).
