Fig. 3.

A single amino acid in the TIM-1 IgV domain responsible for the increased ability of Vero E6 TIM-1 to promote entry of VSV pseudotyped with filovirus GPs. (A) Schematic representation of WT and mutant TIM-1s of Vero E6 and COS-1. A Vero E6 mutant TIM-1 containing an asparagine-to-histidine substitution (N48H) and a COS-1 mutant containing a histidine-to-asparagine substitution (H48N) were constructed. (B, C) 293T cells expressing WT and mutant TIM-1s were stained with the anti-TIM-1 polyclonal antibody and analyzed by flow cytometry (B) and the TIM-1 expression was quantified using MFI (C). Open and shaded histograms (B) indicate fluorescent intensity of TIM-1-expressing cells and vector-transduced control cells, respectively. (D, E) 293T cells expressing TIM-1s and control cells were infected with VSVΔG-EBOV, -RESTV, -MARV, -RAVV, and -LLOV GPs at a MOI of 0.02–0.04. The luciferase activity was measured 24 h postinfection. The means and SDs of three independent experiments are shown. Significance was calculated using student’s t-test (^∗P < 0.05, ^∗∗P < 0.01).