Fig. 6

Effect of nanoparticles on the inhibition of pseudo virus and SARS-CoV-2 infection. H1299 cells were treated with nanoparticles or BGB324 for 24 h before being infected with pseudotyped lentivirus or SARS-CoV-2/NTU13. After 1 h of infection, the virus-containing media was removed and replaced with fresh media. (A) For cells infected with pseudotyped lentivirus, the GFP expression was evaluated after 72 h using microscopy images (upper panel). The percent inhibition (%) was calculated as 1-(GFP signal in the treated sample/ (GFP signal in the untreated control) × 100. BF, bright field. Scale bar = 200 μm. Data points represent the mean of three independent experiments ± SD. (B) Images of H1299 cells infected with SARS-CoV-2/NTU13 for 48 h. Scale bar = 100 μm. (C) Plaque formation assay was performed with H1299 cells infected with SARS-CoV-2/NTU13. The percentage of inhibition was calculated as 1-(VD/VC) × 100, where VD and VC refer to the virus titer in the treated and untreated of the test compound, respectively. The data points represent the means of three independent experiments ± SD. (D) Viral yield reduction assay was performed using qRT-PCR to detect the amount of viral RNA. The percentage of inhibition was calculated as 1-(VD/VC) × 100, where VD and VC refer to the virus titer in the treated and untreated of the test compound, respectively. The data points represent the means of three independent experiments ± SD. *p < 0.05 and ***p < 0.001