To cause COVID-19 disease, the SARS-CoV-2 virus must first enter a host cell. To do this, it uses its so-called spike protein connecting the host cell's own receptor (e.g., ACE2) to penetrate the cell. Cholesterol seems to be indispensable in this process.

Cholesterol is an alcohol from the group of fats, which is mainly needed as a component for cell membranes. Approximately two-thirds of the required cholesterol is produced by the body itself. itself. The rest is absorbed through food. Surpluses of cholesterol can lead to arteriosclerosis.

The scientists developed a microscopy-based cell fusion assay in which they simulated SARS-CoV-2 infection in cell lines. For this purpose, the researchers modified cells to carry either the viral spike protein or the ACE2 receptor. The researchers found out that cells that carried ACE2 pushed forward to cells with spike proteins, and when they came together, the membranes of the cells fused. They further observed that infected cells were continually fusing melting their contents into composite cells called syncytia. Additionally, the scientists remarked that SARS2-CoV-2 infection depends on the membrane cholesterol of the virus, but not that of the host cell. 

The researchers tested about 6,000 compounds to find out which ones were suited to disrupt the interaction between the spike protein and the ACE2 receptor. From previous research, it was already known that the body's immune system is able to produce a cholesterol-degrading chemical as part of the body's defense response to the virus. In their tests, many effective compounds prevented fusion by pulling cholesterol from the plasma membrane.

The research findings were published in BioRxiv but have not yet been peer peer-reviewed:
David W. Sanders et al (2020). SARS-CoV-2 Requires Cholesterol for Viral Entry and Pathological Syncytia Formation, bioRxiv. DOI: 10.1101/2020.12.14.422737
https://www.biorxiv.org/content/10.1101/2020.12.14.422737v1

Source:
https://www.labroots.com/trending/microbiology/19681/cholesterol-enables-sars-cov-2-invade-create-mega-cells

More information:
https://softlivingmatter.princeton.edu/