SARS-CoV-2 entry into human airway organoids is serine protease-mediated and facilitated by the multibasic cleavage site
- Erasmus MC, Netherlands
Abstract
Coronavirus entry is mediated by the spike protein which binds the receptor and mediates fusion after cleavage by host proteases. The proteases that mediate entry differ between cell lines and it is currently unclear which proteases are relevant in vivo. A remarkable feature of the SARS-CoV-2 spike is the presence of a multibasic cleavage site (MBCS), which is absent in the SARS-CoV spike. Here, we report that the SARS-CoV-2 spike MBCS increases infectivity on human airway organoids (hAOs). Compared with SARS-CoV, SARS-CoV-2 entered faster into Calu-3 cells, and more frequently formed syncytia in hAOs. Moreover, the MBCS increased entry speed and plasma membrane serine protease usage relative to cathepsin-mediated endosomal entry. Blocking serine proteases, but not cathepsins, effectively inhibited SARS-CoV-2 entry and replication in hAOs. Our findings demonstrate that SARS-CoV-2 enters relevant airway cells using serine proteases, and suggest that the MBCS is an adaptation to this viral entry strategy.
Data availability
All data generated or analysed during this study are included in the manuscript and supporting files
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Author details
Funding
Nederlandse Organisatie voor Wetenschappelijk Onderzoek (0.22.005.032)
- Bart L Haagmans
ZonMw (10150062010008)
- Bart L Haagmans
Health Holland (LSHM19136)
- Bart L Haagmans
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Copyright
© 2021, Mykytyn et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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SARS-CoV-2 entry into human airway organoids is serine protease-mediated and facilitated by the multibasic cleavage site
eLife 10:e64508.
https://doi.org/10.7554/eLife.64508
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