高剂量PM2.5诱导卵清蛋白致哮喘小鼠肺损伤及其机制  

Lung injury in ovalbumin-challenged asthma mice induced by high-dose PM2.5 and its mechanism

作　　者：徐佳莉[1] 王莹[1] 陈鹏[1] XU Jiali;WANG Ying;CHEN Peng(Children＇s Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430000, Chin)

机构地区：[1]华中科技大学同济医学院附属武汉儿童医院,湖北武汉430000

出　　处：《细胞与分子免疫学杂志》2017年第10期1297-1302,共6页Chinese Journal of Cellular and Molecular Immunology

基　　金：武汉市科技局项目([2015]203号应用基础2015061701011632)

摘　　要：目的研究不同剂量直径≤2.5μm的细颗粒物(PM2.5)诱导卵清蛋白(OVA)致哮喘小鼠肺损伤的程度。方法雄性BALB/c小鼠被随机分为正常对照组、OVA哮喘组、(1、5、15)mg/m L PM2.5处理的OVA哮喘组。收集支气管肺泡灌洗液(BALF)进行Gimsa染色观察白细胞数量,ELISA检测小鼠血清γ干扰素(IFN-γ)、白细胞介素17(IL-17)和IL-10的含量;实时定量PCR进行外周血单个核细胞(PBMC)Toll样受体4(TLR4)、核因子κB(NF-κB)的mRNA水平;Western blot法检测T细胞表达的T盒(T-bet)、维甲酸相关孤核受体γt(RORγt)和叉头盒P3(FOXP3)蛋白水平;HE染色观察小鼠肺组织病变情况。结果与对照组相比,OVA哮喘组小鼠的肺泡间隔增厚,肺泡腔增大,且出现较明显的炎性细胞浸润,BALF中与炎症反应相关的白细胞数目增多;与OVA哮喘组相比,15 mg/m L PM2.5诱导的哮喘小鼠上述变化极其明显。与对照组相比,OVA哮喘组小鼠血清中IFN-γ、IL-10显著降低,而IL-17显著增加;与OVA哮喘组相比,15 mg/m L PM2.5处理的OVA哮喘组IFN-γ、IL-10含量显著减少,而IL-17含量显著增加。与对照组相比,OVA哮喘组小鼠PBMC中TLR4、NF-κB表达量明显增加,与OVA哮喘组相比,15 mg/m L PM2.5处理OVA哮喘组TLR4、NF-κB表达量显著增加。与对照组相比,OVA哮喘组小鼠T-bet和FOXP3蛋白水平明显降低,RORγt蛋白水平明显升高;与OVA哮喘组相比,15 mg/m L PM2.5处理OVA哮喘组小鼠T-bet和FOXP3蛋白水平极显著降低,而RORγt蛋白水平显著增加。结论 15 mg/m L PM2.5通过激活TLR4/NF-κB信号通路促进OVA诱发的哮喘和肺损伤。Objective To investigate the degree of lung injury induced by different doses of particulate matter with diameters ≤ 2. 5 microm（ PM2. 5） in asthmatic mice. Methods Male BALB/c mice were randomly divided into normal control group,ovalbumin（ OVA） asthma group,1,5,15 mg/mL PM2. 5 treated OVA asthma group. The bronchoalveolar lavage fluid（ BALF） was collected and the number of white blood cells was observed by Gimsa staining. ELISA was used to determine the concentrations of serum cytokines interferon γ（ IFN-γ）,interleukin 17（ IL-17） and IL-10 in the peripheral blood of mice. Real-time quantitative PCR was performed to detect the mRNA expression levels of Toll-like receptor 4（ TLR4）,nuclear factor-κB（ NF-κB） in peripheral blood mononuclear cells（ PBMCs）. The levels of T-bet,RORγt and FOXP3 were tested by Western blotting. The lung tissues were collected and the pathological changes were observed by HE staining.Results Compared with the normal control group,the OVA asthma group showed thickened alveolar septum,enlarged alveolar cavity and more obvious inflammatory cell infiltration,as well as significantly increased white blood cells associated with inflammatory response in the BALF. Whereas,compared with the OVA asthma group,the above mentioned changes in15 mg/mL PM2. 5 treated OVA asthma group were extremely obvious. ELISA showed that the levels of IFN-γ and IL-10 in the serum of the OVA asthma group were significantly lower than those in the control group,while IL-17 significantly increased. Compared with the OVA asthma group,the levels of IFN-γ and IL-10 in 15 mg/mL PM2-treated OVA asthma group significantly decreased,while the content of IL-17 significantly increased. Real-time quantitative PCR showed that the expressions of TLR4 and NF-κB in PBMCs of the OVA asthma group were significantly higher than those in the control group.In 15 mg/mL PM2. 5-treated OVA asthma group,the levels of TLR4 and NF-κB increased significantly as compared with the OVA asthma group. Compare

关 键 词：直径≤2.5μm的细颗粒物(PM2.5) 哮喘 肺损伤 Toll样受体4(TLR4) 核因子κB(NF-κB) 

分 类 号：R392.33[医药卫生—免疫学] R563[医药卫生—基础医学]