Researchers at France's Institut Curie have uncovered a promising avenue for local COVID-19 treatment. By isolating extracellular vesicles in vitro, they've created biological decoys that "cheat" the virus, trapping it before it infects cells. What does this mean for patients?
SARS-CoV-2, the virus behind COVID-19, is studded with spike "S" proteins that give it its crown-like shape. To invade human cells—especially lung cells—the S protein binds to the ACE2 receptor on cell surfaces. TMPRSS2 then cleaves the S protein, enabling viral entry (see diagram below).
In a study published December 28, 2020, in The Journal of Extracellular Vesicles, Clotilde Théry of INSERM and her Institut Curie team isolated extracellular vesicles from cultured cells. These naturally occurring "bubbles" in the body mimic human cell surfaces, displaying ACE2 receptors, with or without TMPRSS2.
The research showed SARS-CoV-2's S protein binds to these vesicles, which act as decoys—trapping the virus, blocking cell attachment, and slashing infectivity. Effectiveness scaled with ACE2 receptor density and improved with TMPRSS2. This positions extracellular vesicles as a credible local therapy to curb infection risk and severity.
"The vesicles we isolated decoy SARS-CoV-2 and neutralize it, making them ideal for local COVID-19 treatment," said Clotilde Théry.
The team is advancing this innovative approach, evaluating feasibility, efficacy, and safety. Success could lead to new drug development.
