Extended Data Fig. 5: Role of VLDLR and ApoER2 in E2–E1-mediated cellular infection by divergent alphaviruses.
From: VLDLR and ApoER2 are receptors for multiple alphaviruses
a, Wild-type (WT) or clonal VLDLR knockout (K.O.) HEK 293T cells were infected with GFP-expressing single-cycle alphavirus RVPs with relative infection measured by FACS. EEEV RVPs more efficiently entered VLDLR K.O. cells, which we suspect could be related to clonal variability, as the cell line was generated by clonal dilution. b, Vero cells were infected with GFP-expressing alphavirus single-cycle RVPs in the presence of the indicated antibodies with relative infection measured by FACS. c, Infection of WT or transduced K562 cells with GFP-expressing single-cycle RVPs. Cells were imaged by fluorescence microscopy. Scale bar is 100 μm. The experiment was performed twice, and representative images are shown. d, Infection of WT or transduced K562 cells with GFP-expressing single-cycle RVPs measured by FACS. NRP2 is a control membrane protein. e, K562 cells expressing VLDLR or ApoER2iso2 were infected with the indicated single-cycle RVPs in the presence of RAP, soluble VLDLR LBD (sVLDLRLBD), or a control protein (transferrin, Tf) with infection measured by FACS. f, WT or transduced K562 cells were infected with the indicated GFP-expressing single-cycle RVPs with infection measured by FACS. g, SFV A774 plaque reduction neutralization test with the indicated proteins performed on Vero cells. h, WT K562 cells or K562 cells transduced to express LDLRAD3 were infected with the indicated GFP-expressing single-cycle RVPs with infection measured by FACS. Means ± standard deviation from an experiment performed once in triplicate (n = 3) (a), or experiments performed twice in triplicate (n = 6) with similar results (b, d–h). One-way ANOVA with Tukey’s multiple comparisons test, ****P < 0.0001 (a, b, d–h). Two-way ANOVA with Šídák’s multiple comparison test, ****P < 0.0001 (g). Cell surface expression of constructs used in (c), (d), and (f) was confirmed with immunostaining (see Extended Data Fig. 3).
