The Science Journal of the American Association for Respiratory Care

2012 OPEN FORUM Abstracts

IMBALANCE OF TH17/TREG CELLS IN MICE WITH CHRONIC CIGARETTE SMOKE EXPOSURE.

Huaying Wang1, Weidong Peng1, Yuesong Weng2, Huajuan Ying1, Hequan Li3, Dajing Xia4, Wanjun Yu1; 1Department of Respiratory Diseases,,Affiliated Yinzhou Hospital,College of Medicine, Ningbo University, Ningbo, China; 2Clinical Laboratory, No. 1 Hospital, Ningbo, China; 3Department of Respiratory Diseases, First Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou, China; 4Institute of Immunology, School of Medicine, Zhejiang University, Hangzhou, China

Background: Recent studies have revealed that autoimmune responses mediated by CD4+ T cells may contribute to the development of chronic obstructive pulmonary disease (COPD). Meanwhile, imbalance of Th17/Treg has been reported to play a key role in the pathogenesis of autoimmune diseases. However, information on Th17/Treg balance in COPD is quite limited. Method: We established a mouse model of COPD induced by chronic cigarette smoke (CS) exposure. Th17 and Treg in lung tissue and peripheral blood were quantified by flow cytometry. The level of the specific transcription factors of both T cell subsets in lung tissue were determined by real-time PCR. The expressions of Th17- and Treg-related cytokines in serum and bronchoalveolar lavage fluid (BALF) were measured by enzyme-linked immunosorbent assay (ELISA). Results: We found that mice with chronic CS exposure showed significant increase in lung Th17 prevalence, retinoic acid orphan receptor (ROR)-γt mRNA and Th17-related cytokines (IL-17A, IL-6 and IL-23). Meanwhile, there was obvious decrease in Treg cells prevalence, Forkhead box (Fox) p3 mRNA and Treg-related cytokine IL-10, as compared to mice underwent sub-acute CS exposure and air-exposure. Similar tendency was also found for the Th17/Treg ratio in peripheral blood. Conclusions: Our study thus reveals that the Th17/Treg imbalance exists in mice with chronic CS exposure, suggesting its potential role in the breakdown of immune self-tolerance in COPD. Further research on regulation of Th17/Treg balance may provide insights into the development of new therapeutic targets for this disease. Sponsored Research - This work described in this article was supported by the Nature Scientific Fund of Ningbo City, P. R. China (Grant No.2009A610113) and the National Natural Science Foundation of P. R. China (Grant No.30872295). The ratio of Th17/Treg in lung tissue and peripheral blood. There was a significant increase in the ratio of Th17/Treg in lung tissue and peripheral blood in mice with chronic CS exposure compared with control and sub-acute CS exposure mice. Values were shown as mean ±SEM of twenty mice per group. * p < 0.05 and ** p < 0.01 versus control group; # p < 0.05 and ## p < 0.01 versus sub-acute CS exposure group.