Nanoparticles in induced sputum – a window to airway inflammation among active smokers
Abstract
Aims: To evaluate the role of nanoparticles (NP) in sputum samples of active smokers as markers of inflammation and disease. Materials & methods: 29 active smokers were included (14 with chronic obstructive pulmonary disease [COPD]) and underwent clinical assessment, pulmonary function tests, sputum induction (with NP analysis) and blood sampling. Results: Higher particle and NP concentrations and smaller mean size directly correlated with clinical parameters such as the COPD Assessment Test score and impulse oscillometry results. Similar correlations were found between NPs and increased sputum IL-1β, IL-6 and TNF-α. Among COPD patients, higher IL-8 and lower IL-10 serum levels also correlated with NP concentrations. Conclusion: This proof-of-concept study shows the potential of sputum NPs as markers of airway inflammation and disease.
Plain language summary
What is this article about? Identifying markers of lung inflammation and diseases could offer early diagnosis and treatment. In this study, we questioned whether nanoparticles in the sputum of active smokers correlate with lung inflammation and disease. What were the results? We found that higher nanoparticle concentration in the sputum and lower mean nanoparticle size correlated with different clinical parameters and inflammatory markers. What do the results mean? This proof-of-concept study suggests that nanoparticle analysis in the sputum of active smokers has potential as a marker that correlates with lung inflammation and disease. Our results should encourage additional research in this field to better understand the role of nanoparticles in the diagnosis, prognosis and treatment of active smokers.
Tweetable abstract
Analysis of nanoparticle characteristics from the sputum of active smokers. Nanoparticle concentration and mean size were found to correlate with sputum inflammatory markers and clinical variables.
Graphical abstract
Papers of special note have been highlighted as: • of interest; •• of considerable interest
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