SARS-CoV-2 requires cholesterol for viral entry and pathological syncytia formation
- Princeton University, United States
- Boston University, United States
- University of Virginia, United States
- Washington University School of Medicine, United States
- Harvard Medical School, United States
Abstract
Many enveloped viruses induce multinucleated cells (syncytia), reflective of membrane fusion events caused by the same machinery that underlies viral entry. These syncytia are thought to facilitate replication and evasion of the host immune response. Here, we report that co-culture of human cells expressing the receptor ACE2 with cells expressing SARS-CoV-2 spike, results in synapse-like intercellular contacts that initiate cell-cell fusion, producing syncytia resembling those we identify in lungs of COVID-19 patients. To assess the mechanism of spike/ACE2-driven membrane fusion, we developed a microscopy-based, cell-cell fusion assay to screen ~6000 drugs and >30 spike variants. Together with quantitative cell biology approaches, the screen reveals an essential role for biophysical aspects of the membrane, particularly cholesterol-rich regions, in spike-mediated fusion, which extends to replication-competent SARS-CoV-2 isolates. Our findings potentially provide a molecular basis for positive outcomes reported in COVID-19 patients taking statins, and suggest new strategies for therapeutics targeting the membrane of SARS-CoV-2 and other fusogenic viruses.
Data availability
All data generated or analyzed during this study are included in the manuscript and supporting files with the exception of raw imaging data (>400,000 Nikon ND2 files), which is not feasible to post online given its massive size (>1.5 TB). This data is available from the lead contact upon request, assuming the interested party provides a server with sufficient storage capacity. Raw data (computed fusion scores) from the drug repurposing screen is available in Supplemental File 1; bioinformatics, Supplemental File 3.
Article and author information
Author details
Clifford P Brangwynne
Funding
National Institute of General Medical Sciences (GM095467)
- Bruce D Levy
National Heart, Lung, and Blood Institute (HL122531)
- Bruce D Levy
National Institute of General Medical Sciences (GM134949)
- Ilya Levental
National Institute of General Medical Sciences (GM124072)
- Ilya Levental
Howard Hughes Medical Institute
- Clifford P Brangwynne
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Ethics
Human subjects: Human pathology studies were performed with the approval of the Institutional Review Board at Brigham and Women's Hospital. Clinical autopsies with full anatomic dissection were performed on SARS-CoV-2 decedents by a board-certified anatomic pathologist (RFP) with appropriateinfectious precautions.
Copyright
© 2021, Sanders 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 requires cholesterol for viral entry and pathological syncytia formation
eLife 10:e65962.
https://doi.org/10.7554/eLife.65962
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