Microparticles in sputum of COPD patients: a potential biomarker of the disease?

• Published in: International journal of chronic obstructive pulmonary disease Vol. 11; no. 1; pp. 527 - 533
• Main Authors: Lacedonia, Donato, Carpagnano, Giovanna Elisiana, Trotta, Teresa, Palladino, Grazia Pia, Panaro, Maria Antonietta, Zoppo, Liugi Davide, Foschino Barbaro, Maria Pia, Porro, Chiara
• Format: Journal Article
• Language: English
• Published: New Zealand Dove Medical Press Limited 01.01.2016; Dove Medical Press Ltd; Dove Medical Press
• Subjects: Aged; Antigens; Apoptosis; Biomarkers - analysis; Body mass index; Cell Count - methods; Cell-Derived Microparticles - pathology; Chronic obstructive pulmonary disease; Cystic fibrosis; Dyspnea; Dyspnea - physiopathology; Flow Cytometry - methods; Forced Expiratory Volume; Genotype & phenotype; Granulocytes; Humans; Lavage; Lung diseases; Male; Middle Aged; Neutrophils; Original Research; Political aspects; Predictive Value of Tests; Prognosis; Pulmonary Disease, Chronic Obstructive - diagnosis; Pulmonary Disease, Chronic Obstructive - pathology; Pulmonary Disease, Chronic Obstructive - physiopathology; Respiratory distress syndrome; Severity of Illness Index; Sputum - cytology; Standard deviation; Statistics as Topic; United Kingdom > UK; United States > US; lung; microparticles; sputum; COPD
• ISSN: 1178-2005; 1176-9106; 1178-2005
• DOI: 10.2147/COPD.S99547

Microparticles (MPs) are small membrane vesicles of 0.1-1 µm which are released by cells following chemical, physical, and apoptotic stimuli. MPs represent more than a miniature version of the cell. Their composition and function depend not only on cellular origin, but also on stimuli. Chronic obstructive pulmonary disease (COPD) is a lung disease characterized by nearly irreversible lung destruction which results in airway limitation. We investigated the presence and source of MPs in sputum of COPD patients to evaluate if changes in MP number and origin may reflect the pathophysiological conditions of disease and may serve as potential biomarkers for diagnostic and prognostic use. Induced sputum samples were collected from 18 male subjects and liquefied with Sputasol. MPs obtained were immunolabeled for leukocyte (CD11a), granulocyte (CD66b), monocyte-macrophage (CD11b), platelets and megakaryocytic cells (CD41), endothelial cells (CD31), and red blood cells (CD235ab) and analyzed by cytofluorimetry. There was a negative correlation between CD31-MPs and forced expiratory volume in 1 second (R=-53, P<0.05) and CD66b-MP level was correlated with worse performance index of COPD such as the Body mass index airflow Obstruction, Dyspnea, and Exercise capacity (BODE); they were negatively correlated with 6-minute walking test: 0.65 and -0.64, respectively (P<0.05). CD235ab-MPs showed a negative correlation with body mass index (R=-0.86, P<0.05), while there was a positive correlation with dyspnea index (R=0.91, P<0.05). The main finding of this study was that MPs were detected in the sputum of patients affected by COPD. The phenotype of some of them was related to the main COPD parameters. These results suggest that MPs could be implicated in the pathogenesis of COPD.