Fig. 1

Characterization of rVSV-SARS-CoV and rVSV-SARS-CoV-2. a Schematic diagrams showing genome organization of rVSV vectors. The original VSV G of rVSV-G was replaced by the SARS-CoV S lacking 19 aa at the C-terminus to generate rVSV-SARS-CoV. The original VSV G gene was replaced by the SARS-CoV-2 S lacking 21 aa at the C-terminus to generate rVSV-SARS-CoV-2. b Purified rVSV-SARS-CoV and rVSV-SARS-CoV-2 from supernatants (Lane 1 and 3), lysates of rVSV -SARS-CoV and rVSV -SARS-CoV-2 infected Vero cells (Lane 2 and 4) and mock-infected Vero cells (Con.) (Lane 5) were blotted with antibodies recognizing the S protein of SARS-CoV or SARS-CoV-2, using GAPDH as input control. c Growth kinetics of rVSV-SARS-CoV and rVSV-SARS-CoV-2. Vero cells were infected by the rVSV viruses (MOI = 0.01) and virus titers in the supernatant were measured at the indicated time points post infection by immunofluorescence on Vero cells in duplicate. d Plaque morphology of rVSVs in Vero cells. The plaques of rVSV-SARS-CoV, rVSV-SARS-CoV-2, and rVSV-G formed 5 days of post-infection on Vero cells. Above data are representative of three independent experiments. e Mutations acquired in the S protein by serial passaging at the 15th passage