The expression of Foxp3 and ROR gamma t in lung tissues from normal smokers and chronic obstructive pulmonary disease patients

► We found a decreased ratio of Foxp3/RORγt in COPD patients. ► We studied the distribution of Foxp3 and RORγt related cells in lung tissue. ► The Foxp3/RORγt ratio was correlated to the pathogenesis of emphysema. ► The Foxp3/RORγt ratio was correlated to airway limitation of COPD patients.