increased genes expression levels of cytokines related to th17/treg cells in peripheral blood mononuclear cell correlate with clinical severity in copd and mustard gas-exposed patients

The long lasting inflammation and immune dysregulation is one of the main mechanisms involved in lung complication of veterans exposed to sulfur mustard (sm) gas. th17/treg cells have an important role in immunopathogenesis of chronic obstructive pulmonary disease (copd) and mustard lung disease. in this study, expression of cytokines genes levels related to th17/treg cells was determined in peripheral blood mononuclear (pbmc) of mustard lung patients and was compared with copd patients and healthy controls (hc). real time-polymerase chain reaction was used to assay genes expression levels of th17 related cytokines (il-17, il-6 and tgf-β) and treg related cytokines (il-10, tgf-β). il-17 gene expression level considerably was higher in sm patients (9.98±0.65, p<0.001), and copd (4.75±0.71, p<0.001), compare to hc group. also, gene expression level of il-6 in the sm group (3.31±0.93, p<0.001) and copd group (2.93±0.21, p<0.001) were significantly higher than the hc group. the il-10 gene expression level showed a high increase in sm patients (4.12±0.91, p<0.01), and copd (2.1±0.45, p<0.01). finally, the tgf-β gene expression level was increased in sm patients (4.91±0.69, p<0.001) as well as in copd group (5.41±0.78, p<0.001). in sm patients, il-17 (r=-0.721, p<0.05), il-6 (r=-0.621, p<0.05) and tgf-β (r=-0.658, p<0.05) had significant negative association with fev1 (%). inversely, il-10 showed positive correlation (r=0.673) with fev1 (%). th17/treg cells related cytokines genes were highly expressed and imbalanced in peripheral blood mononuclear cells of sm and copd patients which correlated with pulmonary dysfunction.