Fig. 1. Antiviral assay based on immunofluorescent staining using anti-dsRNA antibody showed that remdesivir potently inhibits SARS-CoV-2 infection. (A) Vero cells were treated with increasing concentrations of remdesivir and infected with SARS-CoV-2 (2 MOI). Twenty-four hours post-infection, infected cells were stained with anti-dsRNA antibody and visualized with Alexa Fluor 488-conjugated secondary antibody (green). Nuclei were stained with Hoechst 33342 (blue). (B) Virus infection was calculated by counting the stained cells and antiviral activity (IC50) was determined from the dose-response curve.