Fig. 6.

Macrophage infection driven by Zaire and Reston ebolavirus as well as Marburg virus glycoproteins is cathepsin-dependent. A. Macrophages were preincubated with 4 μM CA074Me before infection with pseudotypes bearing the indicated GPs, normalized for equal infectivity. Luciferase activity in cell lysates was measured at 72 h post infection. B. Macrophages were preincubated with the indicated concentrations of leupeptin prior to infection with ZEBOV-GP or MARV-GP pseudoparticles. C. The experiment was carried out as described in (B) but the cells were treated with the indicated concentrations CA074Me prior to infection. The results of representative experiments performed in triplicates are shown in A–C; error bars indicate SD. Similar results were obtained in two independent experiments.