Comparison of Treg and Teff cells in healthy and COPD smokers.

Rationale: COPD is characterized by an abnormal regulatory T cell (Treg) response and increases in Th1 and Th17 cell responses. It is unclear if dysregulation of miRNAs within Treg alters the adaptive immunophenotype in COPD. Objectives: To compare the miRNA profile of COPD Treg cells with that of healthy controls and to explore the function of differentially expressed miRNAs. Methods: Treg cells (CD4+CD25+CD49-CD127-) and T effector (CD4+CD25-) cells were obtained from the peripheral blood of 4 nonsmokers, 4 healthy current smokers, and 4 COPD current smokers for analysis of miRNA expression, matching them for age and sex. We assessed expression initially by microarray analysis on the Illumina miRNA platform then conducted real time RT-PCR validation of the microarray results. 24 samples were analyzed. 8 from each patient group of healthy Normal, Healthy Smoker, and COPD Smoker.