Persistence of Th17/Tc17 cell expression upon smoking cessation in mice with cigarette smoke-induced emphysema.
Th17 and Tc17 cells may be involved in the pathogenesis of chronic obstructive pulmonary disease (COPD), a disease caused predominantly by cigarette smoking. Smoking cessation is the only intervention in the management of COPD. However, even after cessation, the airway inflammation may be present. In the current study, mice were exposed to room air or cigarette smoke for 24 weeks or 24 weeks followed by 12 weeks of cessation. Morphological changes were evaluated by mean linear intercepts (Lm) and destructive index (DI). The frequencies of CD8(+)IL-17(+)(Tc17) and CD4(+)IL-17(+)(Th17) cells, the mRNA levels of ROR gamma and IL-17, and the levels of IL-8, TNF-alpha, and IFN-gamma in lungs or bronchoalveolar lavage fluid of mice were assayed. Here we demonstrated that alveolar enlargement and destruction induced by cigarette smoke exposure were irreversible and that cigarette smokeenhanced these T-cell subsets, and related cytokines were not significantly reduced after smoking cessation. In addition, the frequencies of Th17 and Tc17 cells in lungs of smoke-exposed mice and cessation mice were positively correlated with emphysematous lesions. More important, the frequencies of Tc17 cells were much higher than Th17 cells, and there was a significantly positive correlation between Th17 and Tc17. These results suggested that Th17/Tc17 infiltration in lungs may play a critical role in sustaining lung inflammation in emphysema. Blocking the abnormally increased numbers of Tc17 and Th17 cells may be a reasonable therapeutic strategy for emphysema.
Department of Respiratory Medicine, The First Affiliated Hospital of Guangxi Medical University, Nanning, Guangxi 530021, China ; Department of Respiratory Medicine, The Eighth People's Hospital of Nanning, Nanning, Guangxi 530001, China.
Min-Chao
MC
Duan
Department of Respiratory Medicine, The First Affiliated Hospital of Guangxi Medical University, Nanning, Guangxi 530021, China.
Hai-Juan
HJ
Tang
Department of Respiratory Medicine, The First Affiliated Hospital of Guangxi Medical University, Nanning, Guangxi 530021, China.
Xiao-Ning
XN
Zhong
Department of Respiratory Medicine, The First Affiliated Hospital of Guangxi Medical University, Nanning, Guangxi 530021, China.
Ying
Y
Huang
D000818:Animals; D001992:Bronchoalveolar Lavage Fluid; D004195:Disease Models, Animal; D020381:Interleukin-17 / Q000235:genetics / Q000378:metabolism; D016209:Interleukin-8 / Q000378:metabolism; D008168:Lung / Q000276:immunology / Q000378:metabolism / Q000473:pathology; D008297:Male; D051379:Mice; D057132:Nuclear Receptor Subfamily 1, Group F, Member 3 / Q000235:genetics / Q000378:metabolism; D011656:Pulmonary Emphysema / Q000209:etiology*; D012907:Smoking; D016540:Smoking Cessation; D016176:T-Lymphocyte Subsets / Q000276:immunology* / Q000378:metabolism*; D058504:Th17 Cells / Q000276:immunology* / Q000378:metabolism*; D014409:Tumor Necrosis Factor-alpha / Q000378:metabolism
D020381:Interleukin-17; D016209:Interleukin-8; D057132:Nuclear Receptor Subfamily 1, Group F, Member 3; D014409:Tumor Necrosis Factor-alpha