Figure 3. hTIM1-mediated entry of pseudoviruses and VLPs is PS dependent.

(A) A hTIM1 variant deficient in PS binding (AA-hTIM1) does not support viral entry. 293T cells were transduced with hACE2 (mock), hTIM1 or AA-hTIM1, and infected 2 days later with the indicated pseudoviruses or WNV VLPs. Entry was determined by GFP-expression measured by flow cytometry. Figure depicts representative results from one of three independent, duplicated experiments. M.f.i.: mean fluorescent intensity. (B) In parallel with the infection in A, expression levels of hTIM1 and AA-hTIM1 were assessed as in Figure 1A. (C) hTIM1-mediated virus entry enhancement is efficiently blocked by PS-containing liposomes. 293T cells transduced with hACE2 (mock) or hTIM1 were preincubated for 20 min at room temperature with medium alone (none) or with liposomes consisting of either 50% PS and 50% PC (PS/PC) or PC alone (PC). Pseudoviruses or WNV VLPs were then added for a 30 min infection at 37°C, after which unbound liposomes and viruses were washed away and cells supplemented with fresh medium. Entry was quantified as in A and normalized to those of untreated hTIM1-expressing cells. Figure shows mean+SD of three independent, duplicated experiments.