An immunotherapeutic method for COVID-19 patients: a soluble ACE2-Anti-CD16 VHH to block SARS-CoV-2 Spike protein

The third outbreak of coronavirus (CoV) infection (after SARS-CoV and MERS-CoV) caused by a novel CoV (SARS-CoV-2) of the genus Beta-coronavirus has become a global pandemic. CoVs are enveloped viruses whose proteins include spike (S), membrane (M), and envelope (E) which are embedded in the viral envelope. The glycosylated S protein, which forms homo-trimeric spikes on the surface of the viral particle, mediates viral entry into host cells. SARS-CoV-2, like SARS-CoV, uses the Angiotensin-Converting Enzyme 2 (ACE2) cell surface protein for cellular entry. An attractive anti-viral approach is targeting virus entry into cells, for which three strategies are suggested: 1) direct targeting of the viral glycoprotein; 2) targeting the viral receptor on the cell surface; and 3) using soluble (s) ACE2 that binds to S protein thereby neutralizing the virus. In this article, the advantages and disadvantages of these strategies are explained. Moreover, we propose that fusion of the sACE2 to anti-CD16 to produce a bi-speci?c molecule could be a promising anti-viral strategy.

Automated summary

The third outbreak of coronavirus (CoV) infection caused by SARS-CoV-2 has become a global pandemic, with the virus entering host cells primarily through the interaction between viral proteins and the ACE2 cell surface protein. Strategies to target virus entry into cells include direct targeting of viral glycoproteins, viral receptors on the cell surface, and the use of soluble ACE2 to neutralize the virus. Fusion of sACE2 to anti-CD16 to produce a bi-specific molecule could be a promising anti-viral strategy.