CCR6、Th9细胞、Th17/Treg细胞失衡在大鼠肺纤维化中的表达及意义

摘要

Objective To study the expression and significance of CCR6,Th9 related factors and Th17/Treg imbal-ance in rats with pulmonary fibrosis.Methods 63 rats (male SD)were randomly divided into three groups:Normal sa-line control group ( N group ),Pulmonary fibrosis model group (F group ),Dexamethasone treatment group ( D group).Made the rat model of pulmonary fibrosis by injecting bleomycin through the trachea.The lung tissues and the bronchoalveolar lavage fluid of three groups rats were taken at 7 d,14 d and 28 d respectively.HE staining was used to observe the pathological changes of lung tissue in rats.The expression of CCR6 and IL-9 in lung tissue of three groups were evaluated by immunohistochemistry.Detection of PU.1mRNA level in bronchoalveolar lavage fluid by fluores-cence PCR.Flow cytometry was used to detect the expression of Th17 and Treg cell.And analyzed the correlation be-tween CCR6 ,Th9 and Th17/Treg cell.Results 1 .Compared with the N group,the inflammation degree and the pulmo-nary fibrosis degree of the lung tissue was significant in F group and D group,and pulmonary inflammation in the 7d is most obvious.2.About the level of the CCR6,PU.1mRNA,IL-9,Th17,F,D group of rats at different time points were significantly higher than N group(P<0.05).The expression level of Treg cells in F and D group was lower than that in control group(P<0.05).3.The expression levels of CCR6,Th9 and PU.1mRNA were significantly positively correla-ted with Th17,and negatively correlated with Treg (P<0.01).Conclusion Compared with the control group,the ex-pression levels of CCR6,Th9 related factors and Th17/Treg were significantly increased in rats with pulmonary fibro-sis.It is concluded that CCR6,Th9 related factors may be involved in the pathogenesis of pulmonary fibrosis about Th17/Treg imbalance to promote the proliferation of lung fibroblasts.It may plays an important role in the pathogene-sis of pulmonary fibrosis.%目的 研究CCR6、Th9细胞、Th17/Treg失衡在大鼠肺纤维化中的表达及意义.方法 采取随机分组原则将63只雄性SD大鼠分为三组:生理盐水对照组(N组)、肺纤维化模型组(F组)、地塞米松治疗组(D组),经气管内注入博来霉素制作大鼠肺纤维化模型,分别于第7 d、第14 d、第28 d留取各组大鼠肺组织、肺泡灌洗液,应用HE染色观察大鼠模型肺组织病理改变;免疫组化法评价三组肺组织中CCR6、IL-9表达情况;荧光PCR法检测肺泡灌洗液PU.1 mRNA水平,流式细胞术检测Th17、Treg的表达;并分析CCR6、Th9细胞与Th17/Treg的相互关系.结果 1.F组、D组与N组相比,肺组织炎症程度、肺纤维化程度显著,肺部炎症以造模第7 d最明显.2.对于CCR6、PU.1mRNA、IL-9、Th17,与N组相比较,F、D组大鼠不同时间点表达均明显增高(P<0.05),以造模第7 d最明显;F、D组大鼠Treg细胞表达水平较对照组降低(P<0.05).3.CCR6、Th9、PU.1mRNA表达水平与Th17有显著正相关性,与Treg有显著负相关(P均<0.01).结论 本研究大鼠肺纤维化模型CCR6、Th9细胞与Th17/Treg比值各时间点表达水平较对照组均升高;推断CCR6、Th9细胞可能参与Th17/Treg失衡在肺纤维化免疫炎症的发生过程,进而促进肺组织纤维细胞增殖,在肺纤维化的发生机制中起到重要作用.