哮喘小鼠肺组织中转录因子RORγt的表达与气道炎症的关系

Expression of RORγt in pulmonary tissue of asthmatic mice and its relationship to airway inflammation

目的:探讨Th17细胞转录因子RORγt在支气管哮喘小鼠肺组织中的表达及其与哮喘气道炎症的关系。方法:采用卵清蛋白(OVA)致敏方法建立支气管哮喘小鼠模型;BALB/c小鼠30只随机分为对照组、哮喘组、地塞米松治疗组各10只。采用酶联免疫吸附试验(ELISA)方法检测小鼠肺泡灌洗液(BALF)、血清中白细胞介素17(IL-17)水平;HE染色评价各组小鼠气道炎症情况;逆转录聚合酶链反应(RT-PCR)方法检测肺组织IL-17、RORγt mRNA表达水平;免疫印记(Western blot)方法检测肺组织RORγt蛋白表达水平。结果:哮喘组小鼠肺组织RORγt mRNA、蛋白水平及IL-17水平均明显高于对照组和地塞米松治疗组(P<0.05),RORγt蛋白表达量与嗜酸性粒细胞数、淋巴细胞数、中性粒细胞数、BALF、外周血中IL-17含量、肺组织IL-17 mRNA表达量均呈正相关关系(r=0.789、0.795、0.902、0.669、0.806、0.883,P值均<0.01)。结论:RORγt在支气管哮喘小鼠肺组织呈高表达,其表达水平与气道炎症密切相关,参与了哮喘气道炎症的发生过程。

Objective：To explore the expression of RORγt in pulmonary tissue of asthmatic mice and to investigate the association between the expression of RORγt and the airway inflammation. Methods： Thirty female BLAB/c mice were randomly divided into the control group,asthmatic group and dexamethasone （Dex）-treated group. The asthma model was induced by classical method with ovalbumin（OVA）. The concentration of IL-17 in bronchoalveolar lavage fluid （BALF） and serum was measured by enzyme-linked immunosorbent assay（ ELISA）. Airway inflammation was evaluated by HE staining. The expressions of IL-17, RORγt mRNA and protein was measured by reverse transcription- polymerase chain reaction（RT-PCR） and Western blot respectively. Results：The level of IL-17, RORγt mRNA and protein of asthmatic group was significantly higher than those of control group and Dexamethasone treated group （ P 〈 0.05 ） ; the expression of RORγt protein was positively correlated with the numbers of eosinophils, lymphocytes and neutrophils in BALF, with the concentrations of IL-17 in both BALF and sera, and with the mRNA of IL-17 in lung tissues（r = 0.789,0.795,0.902,0.669,0.806,0.883,all P 〈 0.01） .Conclusion：The expression of RORγt in pulmonary tissue of asthmatic mice is high and correlated with the airway inflammation. RORγt may play a important role in the formation of airway inflammation in the asthma.