October 15, 2020

Possible COVID-19 “decoy”

It might be possible to use vesicles carrying the receptor for SARS-CoV-2, the virus that causes COVID-19, to bind the virus and prevent infection.

The novel coronavirus, SARS-CoV-2, must bind to the cell surface receptor ACE2 to enter cells and cause infection. Recently a preclinical study by an international research team found that the presence of a recombinant soluble form of human ACE2 reduced viral growth and inhibited infection. 

This raises the possibility that ACE2 carried by extracellular vesicles or nanoparticles including exomeres could act as a “decoy” to bind the virus and thus prevent infection.  

To test this hypothesis, Robert Coffey, MD, and colleagues confirmed the presence of ACE2 in small extracellular vesicles secreted by colorectal cancer cell lines. They demonstrated that the receptor-binding domain of the SARS-CoV-2 S protein subunit S1 bound to ACE2-positive extracellular vesicles and exomeres. 

Their findings, published in the journal Gastroenterology, have important implications for the development of strategies to prevent infection by SARS-CoV-2, as well as other pathogenic coronaviruses, the researchers concluded.

Qin Zhang, PhD, Dennis Jeppesen, PhD, and James Higginbotham, PhD, were the paper’s first authors.

The National Institutes of Health, National Cancer Institute, Defense Advanced Research Projects Agency of the US Department of Defense, and the Dolly Parton COVID-19 Research Fund at VUMC supported the research.