Journal: Antiviral Research

Article Title: A highly sensitive cell-based luciferase assay for high-throughput automated screening of SARS-CoV-2 nsp5/3CLpro inhibitors

doi: 10.1016/j.antiviral.2022.105272

Figure Lengend Snippet: Antiviral activity and cytotoxicity of nsp5 inhibitor candidates. A. The structure of the four secondary hit compounds (#5, #24, #35 and #39) is shown and their tertiary amide component is circled. GC376 was used as a control. B. The ability of compounds #5, #24, #35 and #39 to inhibit SARS-CoV-2 replication was evaluated at concentrations corresponding to 3-fold serial-dilutions from 50 to 0.02 μM in a multicycle replication assay on A549-ACE2 cells, followed by RT-qPCR quantification of the viral genomic RNA in the supernatant collected at 72 hpi. In parallel the indicated compounds were tested on A549-ACE2 cells for cell cytotoxicity by the CellTiter-Glo assay. The percent of viral inhibition (open symbols, mean ± SD of technical triplicates) and percent of cytotoxicity (closed symbols, mean ± SD of technical triplicates) were determined as described in the Methods section. One experiment representative of two independent experiments is shown.

Article Snippet: HEK-293T cells (designated as HEK-293T/17 from ATCC, # CRL-11268) and A549 cells stably expressing the human ACE2 receptor (A549-ACE2, kindly provided by O. Schwartz, Institut Pasteur) were grown in complete Dulbecco's modified Eagle's medium (Gibco) supplemented with 10% fetal bovine serum (FBS).

Techniques: Activity Assay, Quantitative RT-PCR, Glo Assay, Inhibition