Fig. 2.
Construction and functional analysis of pseudoviruses. (A) Sequence homology of the RBD of the spike gene of human SARS-CoV BJ01 (H-SARS-CoV-BJ01), bat SARSr-CoV WIV1 (B-SL-CoV-WIV1) and bat SARSr-CoV Rp3 (B-SL-CoV-RP3). The * represents different amino acid sites, and theā²represents the same sites among the key residues between H-SARS-CoV-BJ01 and B-SL-CoV-WIV1. (B) Detection of pseudoviruses bearing different S proteins by western-blot. Pseudoviruses were probed with C-oV S protein polyclonal pntibody (top) and with P24-specific mAbs (bottom) as a control. (C) Measurement of pseudovirus infectivity by determining luciferase activity. HIV-1-luciferase pseudotyped with S protein of the H-SARS-CoV-BJ01, B-SL-CoV-WIV1 and their variants, was incubated with HeLa-bACE2, HeLa-cACE2, HeLa-hACE2 and Vero-E6 cells. After 48 h infection, cell lysates were measured as luciferase activity. The results were presented as the means and standard deviations of data from three independent experiments. The error bars indicate standard deviations.