Human airway cells prevent SARS-CoV-2 multibasic cleavage site cell culture adaptation

Lamers, M. M.; Mykytyn, A. Z.; Breugem, T. I.; Wang, Y.; Wu, D. C.; Riesebosch, S.; van den Doel, P. B.; Schipper, D.; Bestebroer, T.; Wu, N. C.; Haagmans, B. L.

doi:10.1101/2021.01.22.427802

bioRxiv · 10.1101/2021.01.22.427802

Human airway cells prevent SARS-CoV-2 multibasic cleavage site cell culture adaptation

Lamers, M. M.·Mykytyn, A. Z.·Breugem, T. I.·Wang, Y.·Wu, D. C.·Riesebosch, S.·van den Doel, P. B.·Schipper, D.·Bestebroer, T.·Wu, N. C.·Haagmans, B. L.

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Abstract

Virus propagation methods generally use transformed cell lines to grow viruses from clinical specimens, which may force viruses to rapidly adapt to cell culture conditions, a process facilitated by high viral mutation rates. Upon propagation in VeroE6 cells, SARS-CoV-2 may mutate or delete the multibasic cleavage site (MBCS) in the spike protein that facilitates serine protease-mediated entry into human airway cells. We report that propagating SARS-CoV-2 on the human airway cell line Calu-3 - that expresses serine proteases - prevents MBCS mutations. Similar results were obtained using a human airway organoid-based culture system for SARS-CoV-2 propagation. Thus, in-depth knowledge on the biology of a virus can be used to establish methods to prevent cell culture adaptation.

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Lamers, M. M., Mykytyn, A. Z., Breugem, T. I., Wang, Y., Wu, D. C., Riesebosch, S., van den Doel, P. B., Schipper, D., Bestebroer, T., Wu, N. C., Haagmans, B. L.. 2021-01-22. Human airway cells prevent SARS-CoV-2 multibasic cleavage site cell culture adaptation. https://doi.org/10.1101/2021.01.22.427802

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