The microbiome of the lung and its extracellular vesicles in nonsmokers, healthy smokers and COPD patients

People with chronic obstructive pulmonary disease (COPD) have distinct types of bacteria-derived vesicles in the lungs. A team led by Sei Won Lee from the University of Ulsan College of Medicine, South Korea, analyzed both the bacterial communities and the tiny vesicles secreted by these bacteria in the lungs of 13 non-smokers, 13 smokers who did not have COPD and 13 smokers with COPD. In all groups, they found a greater level of biodiversity in the bacteria-derived vesicles than in the bacteria themselves, suggesting that some of these vesicles may originate outside the airways. The vesicle diversity was especially pronounced in people with COPD. The findings could help explain how these bacterial by products contribute to the immune dysfunction and inflammation that are the hallmark of COPD.