Researchers have developed an inhalable powder that can protect the lungs and airways from viral invasion by strengthening the body’s own mucosal layer. A powder called Spherical Hydrogel Inhalation for Enhanced Lung Defense (SHIELD) reduces infection in both mouse and non-human primate models over a 24-hour period, with repeated dosing without affecting normal lung function. can do.
“The idea behind this study is simple: in order for a virus to reach and infect cells, it must penetrate mucus, so to prevent the virus from reaching lung cells, it binds with its own mucus. We created an inhalable bioadhesive that works well.” Ke Cheng, corresponding author of the paper describing the work. “Mucous is the body’s natural hydrogel barrier. We’re just strengthening that barrier.”
Cheng is a Randall B. Terry, Jr. Distinguished Professor of Regenerative Medicine at the North Carolina State University School of Veterinary Medicine and a Professor at the North Carolina State University/UNC-Chapel Hill Joint Department of Biomedical Engineering.
The inhalable powder microparticles consist of gelatin and poly(acrylic acid) grafted with non-toxic esters. When introduced into moist environments such as the respiratory tract and lungs, the microparticles swell and adhere to the mucosal layers, increasing the ‘stickiness’ of the mucus.
Effects are strongest in the first 8 hours after inhalation. SHIELD biodegrades over her 48 hours and is completely removed from her body.
In a mouse model, SHIELD blocked SARS-CoV-2 pseudoviral particles with an efficiency of 75% 4 hours after inhalation, dropping to 18% after 24 hours. Researchers found similar results in tests against pneumonia and the H1N1 virus.
In non-human primate models of both the original SARS-CoV-2 variant and the Delta SARS-CoV-2 variant, subjects treated with SHIELD had a 50- to 300-fold reduction in viral load compared to control subjects, There were no symptoms commonly associated with infection. Primates such as lung inflammation and fibrosis. Primates do not display the same symptoms of infection as humans, so viral load is the standard marker used to determine exposure.
Researchers also examined potential toxicity both in vitro and in vivo. Ninety-five percent of cell cultures exposed to high concentrations (10 mg ml) of his SHIELD remained healthy, and mice dosed daily for 2 weeks had normal lung and respiratory function.
“SHIELD is easier and safer to use than other physical barriers and antiviral chemicals,” says Cheng. “In situations where masking is difficult, such as during strenuous exercise, eating or drinking, or having close social interactions, it acts like an ‘invisible mask.’ On top of physical masking, he uses SHIELD to provide protection. can also be strengthened.
“But the beauty of SHIELD is that it is not necessarily limited to protection against COVID-19 or the flu. I am considering what to do.”
Original: Inhalable ‘SHIELD’ protects lungs against COVID-19, influenza virus
Than: North Carolina State University
