A spray that could prevent Covid infection from developing

Researchers have created new molecules that can be sprayed into the nose to block the SARS-CoV-2 virus from entering the lungs and causing infection. The Covid-19 virus enters the body through the lungs when people breathe, resulting in illness.
Engineers at the Johns Hopkins University in the US have now created thin, thread-like strands of molecules called supramolecular filaments capable of blocking Covid-19 virus in its tracks. “The idea is that the filaments will work like a sponge to absorb the Covid virus and other viruses before they have the chance to bind to cells in our airways,” said Honggang Cui, an associate professor at Johns Hopkins Whiting School of Engineering.
“Even if the therapeutic can block the virus for an hour or two, that can be helpful when people must be in a public setting,” said Cui, who led the research. The key to this approach is the way that the filaments carry a receptor called angiotensin converting enzyme-2, or ACE2 which are also found in cells in the nasal lining, the lung surface, and small intestine. They have many biological roles, such as regulating blood pressure and inflammation. The novel coronavirus enters our bodies primarily through interactions with this receptor.
The team’s newly developed filament, called fACE2, serves as a decoy binding site for the virus, with each filament offering several receptors for the Covid spike protein to attach to, and silences ACE2’s biological functions to avoid potential side effects. “Our plan is that this would be administered as a nasal or oral spray, allowing it to be suspended in the lungs or settle on the surface of airways and lungs. When a person breathes in the Covid virus, the virus will be fooled into binding to the decoy receptor and not the ACE2 receptors on cells,” Cui said. Since the filaments attract SARS-CoV-2’s characteristic spike protein, it should work equally well on any current or future variants, the researchers said. They tested its design in mouse models and found their filament was not only present in the rodents’ lungs up to 24 hours later, but also elicited no inflammation or obvious damage to the lungs’ structures.