Fig. 2. Characterization of S-expressing rMVs.

a Growth kinetics of rMV constructs used to infect Vero cells at an MOI of 0.1. Cell-associated virus titers are indicated in TCID₅₀/ml. b Western blot analysis of SARS-CoV-2 S protein in cell lysates of Vero cells infected with the rMVs expressing SF-dER or S2-dER from either ATU2 or ATU3, with or without the 2P mutation. c Western blot analysis of ultracentrifuged media and cell lysates of Vero infected with rMV-ATU2-SF-2P-dER. d Immunofluorescence staining of Vero cells infected with the indicated rMVs 24 h after infection. Permeabilized or non-permeabilized cells were stained for S (red), MV N (green) and nuclei (blue); ×20 magnification (scale bar, 50 µm). The experiments shown were conducted using two or three biologically independent Vero cell batches.