The role of regulatory T cells (Tregs), damage-associated molecular patterns (DAMPs), and myeloid-derived suppressor cells (MDSCs) in the mechanism of innate and adaptive immune responses in
chronic obstructive pulmonary disease (
COPD) is not well understood.Evaluating the presence of Tregs in the bronchoalveolar lavage fluid (BALF) and peripheral blood in patients with
COPD, and assessment of the relationship between Tregs, MDSCs, and DAMPs as factors activating innate and adaptive immune responses. Description of the association between immune and clinical parameters in
COPD.Thirty-one patients with
COPD were enrolled. Clinical parameters (forced expiratory volume in one second [FEV1], forced vital capacity, total lung capacity [TLC], diffusion capacity of
carbon monoxide, and B-BMI, O-obstruction, D-
dyspnea, E-exercise [BODE]) were assessed. Tregs and MDSCs were investigated in the BALF and blood using
monoclonal antibodies directly conjugated with
fluorochromes in flow cytometry. The levels of
defensin (DEF2),
galectin-1 (Gal-1),
galectin-3 (Gal-3), galectin-9 (Gal-9), heat shock protein-27 (HSP27), and
surfactant protein A were assessed via sandwich
enzyme-linked
immunosorbent assay.The percentage of Tregs was significantly higher in the blood than in the BALF, in contrast to the mean fluorescence intensity of forkhead box P3 (FoxP3). Significant associations were observed between Tregs and HSP27 (r = 0.39),
Gal-1 (r = 0.55), Gal-9 (r = -0.46), and MDSCs (r = -0.50), and between FoxP3 and
Gal-1 (r = -0.42), Gal-3 (r = -0.39), and MDSCs (r = -0.43). Tregs and clinical parameters, including FEV1%
pred (r = 0.39), residual volume (RV)%
pred (r = -0.56), TLC%
pred (r = -0.55), RV/TLC (r = -0.50), arterial oxygen saturation (r = -0.38), and arterial
oxygen pressure (r = -0.39) were significantly correlated. FoxP3 was significantly interlinked with RV/TLC (r = -0.52), arterial
oxygen pressure (r = 0.42), and BODE index (r = -0.57).The interaction between innate and adaptive immune responses in patients with
COPD was confirmed. The expression of Tregs in BALF may have prognostic value in patients with
COPD. The conversion of immune responses to clinical parameters appears to be associated with disease severity.