Figure 1.

Human NPC1 confers susceptibility to filovirus entry and infection. (A) Viper VH-2 cells were engineered to express empty vector or human NPC1. Expression of human NPC1 was determined by immunoblotting (IB) with an anti-NPC1 antibody. Proteins non-specifically detected by this antibody were used as a loading control. Samples for IB of NPC1 were resolved on one gel and loading controls were resolved on another. (B, C) Infection of control and NPC1-expressing VH-2 cells by wild-type filoviruses (B), or recombinant VSVs bearing VSV or filovirus glycoproteins (C). Infected cells (green) and counter-stained nuclei (blue) were visualized by fluorescence microscopy. Scale bars, 20 μm. (D, E) Infectivity of VSV pseudotypes bearing VSV or filovirus glycoproteins in control and NPC1-expressing VH-2 cells. (E) NPC1-expressing VH-2 cells were pretreated with the cysteine protease inhibitor E-64 (300 μM) for 4 h at 37°C and then exposed to virus. (D, E) Results (n=3) are representative of two independent experiments. Error bars indicate s.d. Asterisk indicates values below the limit of detection. Figure source data can be found in Supplementary data.