Washington: Researchers have created new molecules that can be sprayed into the nose to prevent 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 in, causing illness.
Engineers at Johns Hopkins University in the US have now created thin strands of molecules called supramolecular filaments that can stop the virus in its tracks.
“The idea is that the filaments work like a sponge to absorb the COVID-19 virus and other viruses before they have a chance to attach themselves to cells in our airways,” said Honggang Cui, an associate professor at the Johns Hopkins Whiting School of Engineering. .
“Even though the therapy can block the virus for an hour or two, it can be helpful when people have to be in a public setting,” said Cui, who led the research published in the journal Matter.
Key to this approach is how the filaments carry a receptor called angiotensin-converting enzyme-2, or ACE2, which is also found in cells in the nasal lining, lung surface and small intestine.
They have many biological roles, such as regulating blood pressure and inflammation. The new coronavirus enters our bodies mainly through interactions with this receptor.
The spike protein of the virus clicks on this receptor, much like a key fits into a lock, allowing it to enter the cell and replicate. Once the virus is stuck in the cell, it prevents the cell from performing its normal functions, causing and exacerbating infections.
Researchers know that adding extra ACE2 to the airways can block virus entry, essentially preventing the virus from binding with ACE2 in the lungs. However, since ACE2 has biological functions, simply delivering more ACE2 to the body can have unpredictable complications.
The team’s newly developed strand, called fACE2, serves as a decoy binding site for the virus, with each strand offering different receptors for the COVID-19 spike protein to attach to and silencing ACE2’s biological functions to avoid potential side effects .
“Our plan is for this to be given as a nasal or oral spray, allowing it to either be suspended in the lungs or settle on the surface of the airways and lungs. When a person breathes in the COVID-19 virus, the virus will be induced to bind to the decoy receptor and not the ACE2 receptors on the cells,” Cui said.
Because the filaments attract the characteristic spike protein of SARS-CoV-2, it should work equally well on any current or future variant, the researchers said.
They tested its design in mouse models and found that their filament was not only present in the rodents’ lungs for up to 24 hours later, but caused no obvious inflammation or damage to the lung structures.
Help support honest journalism.
This, the researchers said, suggests that fACE2 can be retained in the lungs for a period of time and is safe. They noted that the molecules may also have the potential to cure people with active COVID-19 infections by counteracting the replication of newly acquired viruses.
“We think fACE2 could also be used on other respiratory viruses that use the ACE2 receptor to infiltrate cells. The filament design is versatile and can be modified to carry various therapeutic proteins that target different receptors,” adds Hongpeng Jia, assistant professor at Johns Hopkins School of Medicine.
Read also | COVID-19 severely impacting manufacturing in India: study