IL-17A抑制Th2细胞分化减轻哮喘小鼠气道嗜酸性粒细胞炎症  

IL-17A inhibits Th2 cell differentiation and alleviates eosinophilic airway inflammation in a mouse model of asthma

作　　者：王熠杰 赵生涛[1] 杨旭[1] 王冉[1] 郭东霖 蒋云秋[1] 王长征[1] 

机构地区：[1]第三军医大学新桥医院全军呼吸内科研究所,全军呼吸病研究重点实验室,重庆400037

出　　处：《第三军医大学学报》2017年第10期954-959,共6页Journal of Third Military Medical University

基　　金：国家自然科学基金面上项目(81270075)~~

摘　　要：目的研究IL-17A对哮喘小鼠Th2细胞分化及其相关炎症的作用。方法 24只C57BL/6J小鼠按随机数字表法分为对照组、哮喘组和IL-17A处理组(n=8)。哮喘组和IL-17A处理组予以卵清蛋白(ovalbumin,OVA)致敏及激发。每次雾化激发前1 h,IL-17A处理组给予重组小鼠IL-17A气道滴入。各步对照均予以生理盐水。末次激发后24 h处死小鼠,收集支气管肺泡灌洗液(bronchoalveolar lavage fluid,BALF)行细胞总数及分类计数。ELISA检测BALF中IL-4、IL-5、IFN-γ、IL-17A的浓度。HE和PAS染色及半定量评分评估小鼠肺部病理变化。流式细胞术检测脾脏和支气管淋巴结Th细胞分化。免疫磁珠分选健康小鼠幼稚CD4^+T细胞,用Th2极化培养基体外培养,并给予IL-17A或等量PBS干预,检测Th2细胞的增殖、凋亡和分化。结果哮喘组较对照组,BALF中细胞总数、嗜酸性粒细胞数及其比例(P<0.05)、IL-4、IL-5、IL-17A浓度均显著增高(P<0.05),IFN-γ浓度显著下降(P<0.05);支气管、血管周围炎症细胞浸润和杯状细胞化生明显加重(P<0.01);脾脏和淋巴结Th2细胞分化比例显著增高(P<0.05)。IL-17A处理组较哮喘组,BALF中的细胞总数[(26.00±5.43)×10~4/mL vs(58.40±26.93)×10~4/mL,P<0.05]、嗜酸性粒细胞数[(8.04±1.98)×10~4/mL vs(31.95±12.28)×10~4/mL,P<0.05]及其比例[(29.93±3.03)%vs(53.47±6.62)%,P<0.01]显著降低,而中性粒细胞数及其比例无明显变化;BALF中Th2相关因子IL-4浓度[(9.86±2.77)pg/mL vs(28.13±4.62)pg/mL,P<0.01]、IL-5浓度[(7.30±0.50)pg/mL vs(10.50±1.10)pg/mL,P<0.01]均显著降低;支气管、血管周围炎症细胞浸润减轻,HE染色半定量评分降低[(2.00±0.51)vs(3.12±0.64),P<0.05],杯状细胞化生减少[(0.80±0.45)vs(2.40±0.55),P<0.01];脾脏[(2.24±0.44)%vs(4.82±1.83)%,P<0.01]和淋巴结[(7.05±0.58)%vs(10.57±1.35)%,P<0.05]中Th2细胞分化比例显著减少。极化培养的幼稚CD4^+T细胞,予IL-17A干预后,诱导分化的Th2细胞比例显著减少(P<0.05),而增�Objective To investigate the effect of IL-17A on the differentiation of Th2 cells and airway inflammation in a mouse model of asthma. Methods Twenty-four C57BL/6J mice were randomly divided into control group, asthmatic group and IL-17A treatment group. The mice in asthmatic group and IL- 17A treatment group were sensitized and challenged with ovalbumin （OVA）, and in the latter group, the mice received intratracheal instillation of IL-17A 1 h before each OVA challenge ; normal saline was used for all the control treatments. The mice were sacrificed 24 h after the last challenge, and the bronchoalveolar lavage fluid （BALF） were collected for cytological examination and detection of IL-4, IL-5, IL-17A, and interferon-γ （IFN-γ） using ELISA. The lung pathologies were assessed semi-quantitatively using HE and PAS staining. The differentiation of Th cells in the spleen and tracheobronchial lymph nodes were analyzed with flow cytometry. The effects of IL-17A on cell proliferation, apoptosis, and differentiation were examined in naive CD4＋T cells sorted by immunomagnetic beads from normal mice. Results Compared with the control mice, the asthmatic mice showed significantly increased total cell and eosinophil counts and eosinophil percentage （P 〈 0.05 ）, elevated IL-4, IL-5, and IL-17A concentrations （ P 〈 0.05 ）, and lowered IFN-γ concentration in the BALF （P 〈 0. 05 ）. The asthmatic mice presented with more obvious inflammatory cell infiltration （P 〈 0. 01 ） and goblet cell hyperplasia （P 〈 0.05 ） and significantly increased proportion of Th2 cells in the spleen and lymph nodes （ P 〈 0.05 ）. IL-17A treatment of the asthmatic mice significantly reduced the total cell number [ （26.00 ± 5.43 ） × 10^4/mL vs （58.40 ± 26.93 ）× 10^4/mL, P 〈 0. 05 ], eosinophil count [ （8.04 ± 1.98） × 10^4/mL vs （31.95 ± 12.28）× 10^4/mL, P 〈 0.05 ] and eosinophil percentage [ （29.93 ± 3.03 ） % vs （53.47 ± 6. 62）%, P 〈 0. 01 ] in the BALF without affecti

关 键 词：支气管哮喘 嗜酸性粒细胞 白介素-17A TH2细胞 

分 类 号：R392.11[医药卫生—免疫学] R392.3[医药卫生—基础医学]