People with lung disorder face risk of severe COVID-19

Melbourne, Researchers have decoded why people with chronic obstructive pulmonary disease (COPD) are at higher risk of developing severe COVID-19, an advance that could lead to the development of new therapeutic interventions to reduce the infection in patients with the lung condition. The researchers from the Centenary Institute and the University of Technology Sydney in Australia noted that in inflammatory lung conditions, COPD causes airway blockage and makes it difficult to breathe. It affects around 400 million people globally.

In the study, published in the American Journal of Respiratory and Critical Care Medicine, the researchers infected differentiated airway cells from COPD patients and healthy people with SARS-CoV-2.

They found that the COPD airway cells had a 24-fold greater infection with SARS-CoV-2 than the healthy cells. The team found that the infected COPD cells had increased levels of transmembrane protease serine 2 (TMPRSS2) and cathepsin B (CTSB). Both are enzymes that SARS-CoV-2 uses to enter the host cell.

Other results from the study showed additional reasons for COPD patient's susceptibility to severe COVID-19. Key anti-viral proteins (interferons) that protect against infection were largely blunted in the COPD patient airway cells. This was a likely trigger in causing increased viral production in COPD patients, the researchers said.  

Initial laboratory drug testing by the researchers, to inhibit the enzymes TMPRSS2 and CTSB, and to target the high inflammation levels, successfully and substantially reduced SARS-CoV-2 viral levels in COPD patient cells, ultimately confirming the study's results. The finding was critical with hundreds of millions of people affected by COPD globally and with COVID-19 likely to be around for many years to come, the researchers added.