Fig 4.

EMC-S-driven cellular entry depends on the activity of cathepsin B and/or L. MRC5 target cells were preincubated with the indicated concentrations of ammonium chloride, MDL28170, dimethyl sulfoxide (DMSO), or phosphate-buffered saline (PBS) for 60 min, followed by inoculation with infectivity-normalized pseudotypes bearing the glycoprotein of VSV, MLV, hCoV-EMC, or EBOV. Luciferase activity in cell lysates was measured at 72 h postinfection. The results of a representative experiment performed in triplicate are shown. Transduction efficiency is shown relative to transduction of PBS-treated cells, which was set as 100%. Error bars indicate SD. Similar results were obtained in another experiment using different pseudotype preparations.