Figure 2.
F0213 inhibits a broad-spectrum of human-pathogenic CoVs replication in human cellular models. (A) Immunofluorescence staining of SARS-CoV-2 NP antigen (Magenta) and MERS-CoV-NP antigen (green), and Vero cell nucleus (blue). Cells (0.1 MOI) were treated by DMSO (0.1%), Rmedesivir (10 µmol/L), GRL0617 (20 µmol/L), or F0213 (10 µmol/L) for 24 h, respectively. Shown are representative images selected from a pool images captured in two independent experiments. (B) Quantification of NP antigen signal using one-way ANOVA when compared with the DMSO group of either SARS-CoV-2 or MERS-CoV infection. ****P < 0.0001 and ns indicates P > 0.05. (C) Dose-response analysis of F0213 against SARS-CoV-2 variants of concern (Alpha, Beta, Delta and Omicron) in VeroE6-TMPRSS2 cells. EC50 was achieved by plaque reduction assays. (D) F0213 inhibited SARS-CoV-2 (0.1 MOI) replication in human primary CMs. Cell lysates were collected for viral load determination. Data represent mean ± SD for n = 3 biological replicates. (E) Antiviral activity of F0213 against MERS-CoV (0.01 MOI, 48 hpi), HCoV-229E (0.001 MOI, 72 hpi), and HCoV-OC43 (0.001 MOI, 72 hpi) in cell lines as indicated. Viral load in the cell lysate was quantified by RT-qPCR assays. Data represent mean ± SD for n = 3 biological replicates. One-way AVONA for statistical analysis were compared with the DMSO group (0 µmol/L), ****P < 0.0001, ***P < 0.001, **P < 0.01 and *P < 0.05