Neutrophil extracellular traps (NETs) may play a critical role in smoking-related chronic airway
inflammation. However, the mechanism by which NETs induced by cigarette
smoke initiate the adaptive immunity in
chronic obstructive pulmonary disease (
COPD) is not fully understood. In this study, we explored the effects of NETs induced by cigarette
smoke on the myeloid dendritic cells (mDCs) and Th1 and Th17 cells. Additionally, we observed the inhibitory effect of
erythromycin on NETs induced by cigarette
smoke. We found that elevated NET levels in the sputum of
COPD patients were correlated with the circulating Th1 response, mDC activation and airflow limitation. NETs induced by cigarette
smoke extract (CSE) could activate monocyte-derived mDCs and promote Th1 and Th17 differentiation in vitro.
Erythromycin effectively inhibited NET formation induced by CSE. In vivo,
erythromycin decreased NETs in the airway and ameliorated
emphysema with Th1 and Th17 cell down-regulation and CD40+ and CD86+ mDCs suppression in mice chronically exposed to cigarette
smoke. These findings provide direct evidence that NETs promote the differentiation of Th1 and Th17 and play a role in the adaptive immunity of smoking-related chronic
lung inflammation.
Erythromycin is a potential therapeutic strategy for NETs inhibition in
COPD.