Increased levels of Th17 cells are associated with non-neuronal acetylcholine in COPD patients

T-lymphocytes, including Th17-cells and T-cells expressing acetylcholine (ACh), are key components of systemic inflammation in chronic obstructive pulmonary disease (COPD). We investigated whether ACh promotes Th17 cells in COPD. ACh, IL-17A, IL-22, ROR?t, FOXP3 expression and AChIL-17A, AChIL-22, AChROR?t coexpression was evaluated in peripheral blood mononuclear cells (PBMC) from COPD patients (n=16), healthy smokers (HS) (n=12) and healthy control subjects (HC) (n=13) (cultured for 48h with PMA) by flow cytometry. Furthermore, we studied the effect of Tiotropium (Spiriva®) (100nM) and Olodaterol (1nM) alone or in combination, and of hemicholinium-3 (50?M) on AChIL-17A, AChIL-22, AChROR?t, and FOXP3 expression in CD3+PBT-cells of PBMC from COPD patients (n=6) cultured for 48h with PMA. CD3+PBT-cells expressing ACh, IL-17A, IL-22 and ROR?t together with CD3+PBT-cells co-expressing AChIL-17A, AChIL-22 and AChROR?t were significantly increased in COPD patients compared to HC and HS subjects with higher levels in HS than in HC without a significant difference. CD3+FOXP3+PBT-cells were increased in HS than in HC and COPD. Tiotropium and Olodaterol reduced the percentage of CD3+PBT-cells co-expressing AChIL-17A, AChIL-22, and AChROR?t while increased the CD3+FOXP3+PBT-cells in PBMC from COPD patients, cultured in vitro for 48h, with an additive effect when used in combination. Hemicholnium-3 reduced the percentage of ACh+IL-17A+, ACh+IL-22+, and ACh+ROR?t+ while it did not affect FOXP3+ expression in CD3+PBT-cells from cultured PBMC from COPD patients. We concluded that ACh might promote the increased levels of Th17-cells in systemic inflammation of COPD. Long-acting ?2-agonists and anticholinergic drugs might contribute to control this event.