Imbalance of Th17/Treg cells in mice with chronic cigarette smoke exposure

► We establish a mouse model of COPD induced by chronic cigarette smoke (CS) exposure. ► Chronic CS exposure intrigues increasing of Th17 prevalence and decreasing of Treg prevalence in lung and peripheral blood. ► Increasing of ROR-γt and decreasing FoxP3 mRNA is observed in mouse with chronic CS exposure. ► Th17/Treg imbalance may play a vital role in the breakdown of immune self-tolerance in COPD.