Reliable, easy-to-handle phenotypic screening platforms are needed for the identification of anti-SARS-CoV-2 compounds. Here, we present caspase 3/7 activity as a readout for monitoring the replication of SARS-CoV-2 isolates from different variants, including a remdesivir-resistant strain, and of other coronaviruses in numerous cell culture models, independently of cytopathogenic effect formation. Compared to other models, the Caco-2 subline Caco-2-F03 displayed superior performance. It possesses a stable SARS-CoV-2 susceptibility phenotype and does not produce false-positive hits due to drug-induced phospholipidosis. A proof-of-concept screen of 1,796 kinase inhibitors identified known and novel antiviral drug candidates including inhibitors of phosphoglycerate dehydrogenase (PHGDH), CDC like kinase 1 (CLK-1), and colony stimulating factor 1 receptor (CSF1R). The activity of the PHGDH inhibitor NCT-503 was further increased in combination with the hexokinase II (HK2) inhibitor 2-deoxy-D-glucose, which is in clinical development for COVID-19. In conclusion, caspase 3/7 activity detection in SARS-CoV-2-infected Caco-2-F03 cells provides a simple phenotypic high-throughput screening platform for SARS-CoV-2 drug candidates that reduces false-positive hits.
- Bojkova, D.
- Reus, P.
- Panosch, L.
- Bechtel, M.
- Rothenburger, T.
- Kandler, J. D.
- Pfeiffer, A.
- Wagner, J. U. G.
- Shumliakivska, M.
- Dimmeler, S.
- Olmer, R.
- Martin, U.
- Vondran, F. W. R.
- Toptan, T.
- Rothweiler, F.
- Zehner, R.
- Rabenau, H. F.
- Osman, K. L.
- Pullan, S. T.
- Carroll, M. W.
- Stack, R.
- Ciesek, S.
- Wass, M. N.
- Michaelis, M.
- Cinatl, J., Jr.
Keywords
- Drugs
- Screening in health technology
- Virology
