RT Journal Article
SR Electronic
T1 Differences in plasma and sputum biomarkers between COPD and COPD–asthma overlap
JF European Respiratory Journal
JO Eur Respir J
FD European Respiratory Society
SP 421
OP 429
DO 10.1183/09031936.00024313
VO 43
IS 2
A1 Hiroshi Iwamoto
A1 Jing Gao
A1 Jukka Koskela
A1 Vuokko Kinnula
A1 Hideo Kobayashi
A1 Tarja Laitinen
A1 Witold Mazur
YR 2014
UL http://erj.ersjournals.com/content/43/2/421.abstract
AB The pathophysiological features of chronic obstructive pulmonary disease (COPD)–asthma overlap are poorly understood and there has been no study of plasma or sputum biomarkers in overlap patients. In order to clarify the similarity and differences between overlap and COPD or asthma, we have investigated four potential biomarkers of COPD: surfactant protein A (SP-A), soluble receptor for advanced glycation end-products (sRAGE), myeloperoxidase (MPO) and neutrophil gelatinase-associated lipocalin (NGAL). SP-A and sRAGE are pneumocyte-derived markers. MPO and NGAL are neutrophil-derived molecules, but NGAL can also be expressed by respiratory epithelial cells. Plasma levels of SP-A and sRAGE and induced sputum levels of MPO and NGAL were measured by enzyme immunoassay/ELISA in 134 subjects: nonsmokers (n=26), smokers (n=23), asthma (n=32), COPD (n=39) and COPD–asthma overlap patients (n=14). In patients with COPD–asthma overlap, sputum MPO and plasma SP-A were significantly elevated whereas plasma sRAGE levels were reduced compared with asthma patients. Only sputum NGAL was significantly elevated in COPD–asthma overlap compared with COPD (p=0.00016) and could be used to differentiate patients with overlap from those with COPD. Increased induced sputum levels of NGAL might be a characteristic feature of overlap, suggesting enhanced neutrophilic airway inflammation and/or airway epithelial injury in COPD–asthma overlap. Increased sputum levels of neutrophil gelatinase-associated lipocalin in COPD–asthma overlap versus COPD/asthma patients http://ow.ly/qxC8X