Fig. 4. Inhibition of SARS-CoV-2 replication in Vero E6 cell by colloidal bismuth subcitrate (CBS). (A) Representative immunofluorescence staining images of Vero E6 cells infected with SARS-CoV-2. The nucleocapsid protein of SARS-CoV-2 (N protein) antigens and cell nuclei (DAPI) were stained in green and blue, respectively. (B) Inhibition of SARS-CoV-2 replication and cytotoxicity of increasing concentrations of colloidal bismuth subcitrate (CBS). Each experiment was performed in triplicates. The data are shown in mean ± sd.