Development and validation of a phenotypic high-content imaging assay for assessing the antiviral activity of small-molecule inhibitors targeting the Zika virus

Bernatchez, J. A.; Yang, Z.; Coste, M.; Li, J.; Beck, S.; Liu, Y.; Clark, A. E.; Zhu, Z.; Luna, L. A.; Sohl, C.; Purse, B. W.; Li, R.; Siqueira-Neto, J. L.

doi:10.1101/302927

bioRxiv · 10.1101/302927

Development and validation of a phenotypic high-content imaging assay for assessing the antiviral activity of small-molecule inhibitors targeting the Zika virus

Bernatchez, J. A.·Yang, Z.·Coste, M.·Li, J.·Beck, S.·Liu, Y.·Clark, A. E.·Zhu, Z.·Luna, L. A.·Sohl, C.·Purse, B. W.·Li, R.·Siqueira-Neto, J. L.

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Abstract

Zika virus (ZIKV) has been linked to the development of microcephaly in newborns, as well as Guillain-Barre syndrome. There are currently no drugs available to treat infection, and accordingly there is an unmet medical need for discovery of new therapies. High-throughput drug screening efforts focusing on indirect readouts of cell viability are prone to a higher frequency of false positives in cases where the virus is viable in the cell but the cytopathic effect is reduced or delayed. Here, we describe a fast and label-free phenotypic high-content imaging assay used to detect cells affected by the viral-induced cytopathic effect (CPE) using automated imaging and analysis. Protection from CPE correlates with a decrease in viral antigen production as observed by immunofluorescence. We trained our assay using a collection of nucleoside analogues against ZIKV; the previously reported antiviral activities of 2-C-methylribonucleosides and ribavirin against the Zika virus in Vero cells were confirmed using our developed method. Profiling of a novel library of 24 natural product derivatives using our assay revealed compound 1 as an inhibitor of ZIKV-induced cytopathic effect; activity of the compound was confirmed in human fetal neural stem cells (NSCs). The described technique can be easily leveraged as a primary screening assay for profiling large compound libraries against ZIKV, and can be expanded to other ZIKV strains and other cell lines displaying morphological changes upon ZIKV infection.

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Bernatchez, J. A., Yang, Z., Coste, M., Li, J., Beck, S., Liu, Y., Clark, A. E., Zhu, Z., Luna, L. A., Sohl, C., Purse, B. W., Li, R., Siqueira-Neto, J. L.. 2018-04-17. Development and validation of a phenotypic high-content imaging assay for assessing the antiviral activity of small-molecule inhibitors targeting the Zika virus. https://doi.org/10.1101/302927

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