Engineers at Johns Hopkins have developed a nasal spray that uses thin, thread-like molecules called supramolecular filaments to prevent harmful viruses, such as COVID-19 and influenza, from entering the lungs. The filaments work like a sponge, absorbing the viruses before they can bind to cells in the airways. The filaments carry a receptor called angiotensin-converting enzyme-2 (ACE2), which the virus uses to enter the body. The filaments act as a decoy binding site for the virus, preventing it from binding to ACE2 in the lungs and avoiding any potential side effects from delivering more ACE2 to the body.
The filaments in the nasal spray are designed to attract SARS-CoV-2 spike protein, making it effective against any current or future variants of the virus. The research team tested the design in mouse models and found that the filament presents in the rodents lungs up to 24 hours after administration and did not cause any obvious damage to lung structures or inflammation, indicating that the spray is safe to use even if it stays in the lungs for a longer period.