Scientists from the University of Dundee have announced new findings they believe could unlock the development of a new type of treatment for lung conditions, including Covid-19.
Researchers studied patients across two studied with the severe inflammatory lung conditions bronchiectasis, where the lungs become scarred and inflamed, and asthma.
Using specialised technology to study lung samples in high resolution, they found that severe lung conditions were characterised by an excessive type of immune response called neutrophil extracellular trap formation (NETs).
The researchers showed that the severity of respiratory symptoms and associated risk of death could be predicted by measuring this immune response and that a commonly used antibiotic, azithromycin, could prevent the immune system from forming NETs.
Furthermore, they demonstrated that reducing NETs in the lungs was then associated with marked improvements in asthma symptoms.
Similar results were found in bronchiectasis, suggesting a treatment target that can work for multiple lung conditions
. Several studies have shown that NETs are key in patients suffering severe Covid-19 symptoms.
Professor James Chalmers and British Lung Foundation-funded PhD student Holly Keir are presenting their work today at the European Respiratory Society Congress, the world’s largest meeting of respiratory doctors and scientists.
Their results will simultaneously be published in the prestigious New England Journal of Medicine.
Holly explained: “The immune system normally tries to clear infections such as viruses or bacteria from the lungs cleanly, quietly, and without damaging the lung tissue around them.
“Our research has shown how this goes wrong in lung conditions. When this happens, the key immune cells, called neutrophils, explode, forming NETs that damage the lungs.
“Many lung conditions are caused by the immune system going too far, too fast, in trying to fight infections.
“Showing how this goes wrong is the key to unlocking new treatments, both for chronic lung conditions and perhaps also for Covid-19.”
A separate study, undertaken in collaboration with Insmed Incorporated, saw Professor Chalmers and colleagues look at a new drug called brensocatib, which blocks excessive neutrophil immune response.
They demonstrated that brensocatib was associated with a reduction in pulmonary exacerbations in non-cystic fibrosis bronchiectasis patients, potentially leading to a reduction in hospital admissions.
Both brensocatib and azithromycin are now being tested in clinical trials with Covid-19, where researchers believe the same excessive immune response is key to severe disease.
Holly added: “Until now, we have had no drugs specifically designed to reduce the most common type of inflammation caused by bacteria and viruses.
“These results are therefore highly significant and could unlock the development of multiple new treatments for patients with lung disease.”