The expression of selected biomarkers at the systemic and local level in patients with COPD

Abstract

Chronic obstructive pulmonary disease (COPD) is characterized by inflammation at both the pulmonary and systemic level. Cytokines involved in COPD pathogenesis may be expressed locally or systemically, and their role in inflammation is not well characterized. The aim of the study was to compare serum and induced sputum (IS) cytokine levels in COPD patients and in controls without respiratory diseases. Method: 30 patients with mild-moderate COPD and 27 controls were enrolled to the study. All patients underwent lung function testing, blood sampling and sputum induction. Analysis of 27 cytokines in serum and IS samples were performed using Luminex platform. Results: COPD patients were older, both groups were similar with regard to gender. COPD patients had significantly higher sputum levels of 14 measured cytokines: Hu IL-1b (3.0 vs. 1.8), IL-6 (17.1 vs. 1.31), IL-7 (0.9 vs. 0.1), IL-8 (550.2 vs. 63.9), IL-12 (0.3 vs. 0.1), IL-13 (0.4 vs. 0.01), IL-15 (9.4 vs. 0.6) , G-CSF (17.9 vs. 1.6), GM-CSF (0.05 vs. 0.01), IP-10 (107.3 vs. 31.5), MCP-1 (5.5 vs. 0.6), MIP-1a (0.4 vs. 0.1), MIP-1b (7.5 vs. 4.8), TNF-α (5.4 vs. 1.2). In contrast serum cytokines levels (except PDGF) in COPD subjects were not elevated compared with controls. It is worth noting that IL-15 and IP-10 sputum levels were increased in COPD patients, and correlated inversely with lung function parameters (p≤ 0.05). These two cytokines are currently being discussed as new, promising COPD markers. Conclusion: elevated levels of selected cytokines were observed in sputum of COPD patients vs. controls. It is possible that in mild-moderate COPD local inflammation plays an important role or systemic inflammation is very poorly expressed.