Figure 3.

Immunofluorescence microscopy analysis of the cell penetration capacity of +21 PfTrx. HeLa cells were incubated in the presence of 0.1 µM positively supercharged (A) or wild-type (B) PfTrx in serum-free medium for 4 h at 37°C, then washed (3X) with 20 U/ml heparin in order to remove cell surface-adsorbed proteins. A representative image of a control incubation performed with +21 PfTrx at 4°C is shown in panel (C). Anti +21 PfTrx (A, C) and anti-wt-PfTrx (B) specific mAbs were used for protein detection (green); nuclei were stained with DAPI (blue) (see ‘Materials and Methods’ for details). Scale bars represent 10 µm.