Effects of glucocorticoid and cysteinyl leukotriene 1 receptor antagonist on CD34+ hematopoietic cells in bone marrow of asthmatic mice

Background Corticosteroids remain the most effective therapy available for asthma. They have widespread effects on asthmatic airway inflammation. However, little is known about the effects of corticosteroids on the production of bone marrow inflammatory cells in asthma. This study observed the effects of glucocorticoid and cysteinyl leukotriene 1 receptor antagonist on CD34+ hematopoietic cells, so as to explore the possible effectiveness of a bone marrow-targeted anti-inflammatory strategy. Methods Balb/c mice were sensitized and challenged with ovalbumin (OVA) to establish an asthmatic model. For two consecutive weeks, asthmatic mice were challenged with OVA while being given either prednisone, montelukast, prednisone plus montelukast, or sterile saline solution. The mice were killed 24 hours after the last challenge with OVA, and bronchoalveolar lavage fluid (BALF), peripheral blood, and bone marrow were collected. Eosinophils in peripheral blood and BALF, and nucleated cells in BALF, peripheral blood, and bone marrow were counted. The percentages of CD34+ cells, CD4+ T lymphocytes and CD8+ T lymphocytes among nucleated cells in peripheral blood and bone marrow were counted by flow cytometry. Immunocytochemistry and in situ hybridization were employed to detect expression of CD34 and interleukin (IL)-5Rα mRNA (CD34+ IL-5Rα mRNA+ cells) among bone marrow hematopoietic cells. Results Compared with the sterile saline solution group, the number of eosinophils in BALF and peripheral blood, CD34+ cells in peripheral blood and bone marrow, and CD34+ IL-5Rα mRNA+ cells in bone marrow of mice from the prednisone and prednisone plus montelukast groups were significantly lower （P<0.01）. The number of eosinophils in BALF from the montelukast group was also significantly lower （P<0.05）. Conclusions The results suggest that, in this asthmatic mouse model, prednisone probably inhibits proliferation, differentiation, and migration of CD34+ cells in bone marrow, blocks eosinophilopoiesis in bone marrow, and interferes with eosinophil migration into peripheral blood and subsequent recruitment in the airway. In addition, montelukast may suppress eosinophil infiltration into the lungs of asthmatic mice. However, a significant inhibitory effect of montelukast on the proliferation and migration of CD34+ cells and a cooperating effect with prednisone on bone marrow of asthmatic mice were not observed.     

吸入脂多糖对哮喘小鼠气道炎症和气道黏液分泌的影响

目的 观察哮喘小鼠吸入脂多糖 （LPS,作为刺激原）其气道炎症和气道黏液分泌的变化 。 方法 30只清洁级BALB/c小鼠随机分为哮喘组 (AST组)、LPS哮喘组 （LAS组）和正常组 (NS组),每组10只。哮喘组用卵清白蛋白 （OVA）致敏和激发制作哮喘模型,LPS哮喘组在哮喘模型的基础上加用LPS (50 μg/mL)雾化吸入30 min,正常组用生理盐水代替OVA。检测各组小鼠支气管肺泡灌洗液 (BALF)细胞总数和细胞分类计数,采用ELISA检测BALF中的白细胞介素4 (IL-4)和肿瘤坏死因子-α （TNF-α）水平,HE染色观察肺部病理学改变,用阿尔辛蓝-过碘酸雪夫 (AB-PAS)染色气道杯状细胞,免疫组织化学法检测肺组织中黏蛋白5ac (Muc5ac)的表达,荧光定量RT-PCR检测Muc5ac mRNA在肺内的表达。并分析Muc5ac蛋白表达与各指标的相关性。 结果 AST及LAS组小鼠较NS组在BALF中的细胞总数、嗜酸性粒细胞、单核细胞、淋巴细胞百分比,IL-4和TNF-α水平、肺组织AB-PAS阳染面积, Muc5ac蛋白和mRNA表达明显升高,其差异均有统计学意义 (P均<0.05)。LAS组较AST组上述气道炎症（除单核细胞数外）和气道黏液高分泌指标明显增高,差异均有统计学意义 (P<0.05)。气道Muc5ac蛋白表达与BALF中细胞总数、嗜酸性粒细胞数、IL-4、TNF-α水平、气道AB-PAS染色阳性着色面积均呈正相关（P均<0.05）。 结论 OVA致敏和激发的哮喘小鼠出现以嗜酸性粒细胞、淋巴细胞浸润为主的气道炎症及杯状细胞增生的气道黏液高分泌,且气道炎症和气道黏液高分泌关系密切。LPS可使气道炎症和气道黏液高分泌加重,可能与LPS激发了体内炎症介质的生成、活化有关。     

糖皮质激素对卵蛋白致敏小鼠骨髓祖细胞扩增反应的干预

目的探讨地塞米松对卵蛋白(OVA)诱导的小鼠骨髓细胞体外扩增的影响作用.方法以OVA及生理盐水致敏并激发BALB/c小鼠,建立各哮喘及对照组模型.分别于OVA激发后2、12、24、48和72h及生理盐水激发后24h处死小鼠,取支气管肺泡灌洗液(BALF)计数其中的白细胞和嗜酸性粒细胞(EOS)的数量.采用半固定培养骨髓细胞,培养基中分别加有白细胞介素5(1ng/ml)和不同浓度的地塞米松(0～ 0.2mg/ml),计数嗜酸性粒祖细胞克隆(Eo-CFU).结果 OVA激发2h以后BALF中白细胞总数和EOS显著高于对照组(P<0.05),过敏原激发24～48h小鼠骨髓Eo-CFU显著高于对照组(P<0.05).经低浓度的地塞米松(30.05 mg/ml)处理后的骨髓细胞Eo-CFU受到抑制(P<0.05)).结论过敏原诱导的气道嗜酸性粒细胞增多和骨髓中造血细胞性祖细胞的分化增殖增强有关,糖皮质激素对过敏原诱导的气道炎症的治疗作用可能部分通过其抑制骨髓造血功能实现的.     

CD69 expression on airway eosinophils and airway inflammation in a murine model of asthma

Background Asthma is a chronic airway disease with inflammation characterized by physiological changes （airway hyper-responsiveness, AHR） and pathological changes （inflammatory cells infiltration and mucus production）. Eosinophils play a key role in the allergic inflammation. But the causative relationship between eosinophils and airway inflammation is hard to prove. One of the reasons is lack of activation marker of murine eosinophils. We investigated the expression of CD69 on murine eosinophils in vitro, the relationship between the expression of CD69 on eosinophils from peripheral blood and bronchoalveolar lavage fluid and on airway inflammation in asthmatic mice. Methods Eosinophils from peripheral blood of IL-5 transgenic mice （NJ.1638） were purified. Mice were divided into five groups： wild type mice sensitized and challenged with saline （WS group）, wild type mice sensitized and challenged with ovalbumin （WO group）, IL-5^-/- mice sensitized and challenged with saline and transferred with purified eosinophils （ISE group）, IL-5^-/- mice sensitized and challenged with OVA and transferred with purified eosinophils （IOE group）, IL-5^-/- mice sensitized and challenged with OVA and transferred with purified eosinophils, pretreated with anti CD4 monoclonal antibody （IOE＋antiCD4mAb group）. IL-5^-/- mice were sensitized with OVA at day 0 and day 14, then challenged with OVA aerosol. On days 24, 25, 26 and 27 purified eosinophils were transferred intratracheally to IL-5^-/- mice. On day 28, blood and BALF were collected and CD69 expression on eosinophils measured by flowcytometry. Results Purified eosinophils did not express CD69. But eosinophils cultured with PMA＋MA, IFN- T, IL-5 or GM-CSF expressed CD69 strongly. Eosinophils from blood of WO, WS group did not express CD69 at all. The numbers of eosinophils in BALF of WO group, IOE group, ISE group and IOE＋antiCD4mAb group were significantly higher than in mice of WS group which did not have eosinophils at all. CD69 expression on eosinophils in BALF of IOE and WO groups was strong. Eosinophils in BALF of ISE and IOE＋antiCDmAb groups did not express CD69. The mucus production result was similar to CD69 expression. There were eosinophils infiltration in lung slides of all groups except WS group. Conclusion Activation in airway of eosinophils could directly lead to airway inflammation.     

咳喘宁雾化吸入对哮喘大鼠肺泡灌洗液白介素-5与嗜酸性粒细胞的影响

目的 观察咳喘宁雾化吸入对肺泡灌洗液（BALF）中白介素-5（IL-5）表达、嗜酸性粒细胞（EOS）计数的影响,探讨其对哮喘大鼠气道炎症的作用机制.方法 将SD雄性幼龄大鼠40只,随机分为正常组、哮喘模型组、咳喘宁干预组、布地奈德干预组,每组10只.经鸡卵蛋白（OVA）致敏后,给予OVA雾化吸入诱发哮喘发作,制作哮喘模型.咳喘宁干预组与布地奈德干预组分别给予咳喘宁口服液1.7 g/ks,布地奈德0.1 mg/kg,正常组与哮喘模型组予以等量生理盐水雾化.雾化7d后,处死大鼠,检测大鼠BALF中IL-5水平和EOS计数.结果 咳喘宁干预组大鼠BALF中的IL-5与EOS明显低于哮喘模型组,差异有统计学意义（P＜0.05）,与布地奈德干预组比较,差异无统计学意义（P＞0.05）.结论 咳喘宁通过雾化吸入能降低哮喘大鼠BALF的IL-5水平及EOS计数,从而改善哮喘大鼠气道炎症状态.     

Brg1通过STAT6促进哮喘气道黏液高分泌

目的研究染色质重构复合物核心催化亚基（Brg1）对哮喘小鼠气道黏液高分泌的影响及其作用机制。方法将6~8周龄 雌性野生型C57bl/6小鼠和Brg1-/-小鼠（Ⅱ型肺泡上皮细胞AEC2s上特异性条件敲低Brg1的C57bl/6小鼠）随机分为4组：正常 对照组、哮喘组、Brg1敲低对照组（Brg1-/-）和Brg1敲低后构建哮喘模型组（Brg1-/-+哮喘）,每组10只。哮喘组和Brg1-/-+哮喘组用 鸡卵清蛋白（OVA）制备过敏性哮喘模型,对照组用生理盐水代替。收取标本,用ELISA检测小鼠支气管肺泡灌洗液（BALF）中 黏蛋白MUC5AC和IL-13的表达。糖原染色检测小鼠气道杯状细胞的增生和黏液分泌,q-PCR和免疫组化检测各组小鼠气道 黏蛋白MUC5AC的表达和定量。Western blot检测各组小鼠肺组织中STAT6、p-STAT6的表达。结果Brg1-/-+哮喘组较哮喘组 气道杯状细胞增生和黏液分泌均显著减少,BALF中IL-13、MUC5AC表达明显降低,肺组织MUC5AC mRNA表达显著降低, 同时肺组织STAT6和磷酸化STAT6显著下调。结论Brg1-/-敲低的小鼠建立哮喘模型时气道黏液分泌较野生型小鼠减轻,其可 能通过影响STAT6从而抑制黏蛋白MUC5AC的表达,抑制支气管哮喘气道黏液高分泌,表明Brg1具有促进哮喘气道黏液高分 泌的作用。     

哮喘小鼠CD34+祖细胞和嗜酸性粒细胞的动态变化及其与CCR3/eotaxin表达的关系

目的 观察不同时间点CD34+祖细胞和嗜酸性粒细胞在哮喘小鼠支气管肺泡灌洗液(BALF)、外周血、骨髓悬液中的动态变化过程,探讨CD34+祖细胞、嗜酸性粒细胞、CCR3/eotaxin与哮喘小鼠肺部炎症的关系。 方法 以C57BL/6小鼠为研究对象,以卵白蛋白作为抗原建立哮喘模型,于最后一次抗原激发后6、12、24、48 h检测BALF、外周血和骨髓中的嗜酸性粒细胞、CD34+祖细胞、eotaxin的变化,检测CD34+祖细胞上CCR3的表达;行肺组织病理切片观察嗜酸性粒细胞浸润;PCR检测肺组织CCR3和eotaxin mRNA水平。 结果 抗原激发后嗜酸性粒细胞数、CD34+细胞数、CD34+/CCR3+细胞数在BALF、外周血、骨髓悬液中有不同程度的增加。模型组BALF的eotaxin水平在抗原激发后6 h与对照组相比有明显增加(P<0.05),并一直持续到24 h。外周血和骨髓悬液中eotaxin水平与对照组相比差异无统计学意义(均P>0.05)。模型组各时间点肺组织eotaxin mRNA和CCR3 mRNA的表达与对照组相比均有明显增加。BALF中嗜酸性粒细胞数分别与骨髓悬液中嗜酸性粒细胞数、CD34+/CCR3+细胞数呈正相关,而与骨髓悬液中CD34+细胞数无明显相关性。 结论 ①哮喘小鼠气道局部嗜酸性粒细胞增多与骨髓CD34+祖细胞上CCR3表达上调有关。②CCR3/eotaxin参与CD34+祖细胞分化和趋化,与哮喘小鼠气道嗜酸性粒细胞浸润密切相关。      

布地奈德对哮喘小鼠模型IL-22的调控作用

目的观察白介素22(IL-22)在哮喘模型中的作用,研究布地奈德对哮喘小鼠模型气道炎症及IL-22的调控作用。方法 24只BALB/c小鼠随机分为对照组、哮喘模型组和布地奈德组3组,用卵清蛋白(OVA)致敏、激发小鼠以制备哮喘模型。小鼠肺组织进行HE及AB-PAS染色,进行气道炎症评分,ELISA法检测3组小鼠肺泡灌洗液(BALF)中IL-22的水平,实时荧光定量PCR检测小鼠肺组织中IL-22mRNA的表达水平。结果与对照组相比较,哮喘小鼠肺组织炎症评分增加,BALF中IL-22水平增高,肺组织中IL-22mRNA表达水平升高,差异均具有统计学意义。给予布地奈德治疗后,小鼠气道炎症评分及肺组织IL-22mRNA的表达水平均较哮喘组降低,差异具有统计学意义。结论布地奈德对哮喘气道炎症的治疗作用与其抑制肺内IL-22的表达和分泌有关。     

屋尘螨诱导气道上皮TLR4表达和影响T淋巴细胞分化在哮喘气道炎症中的作用

目的研究屋尘螨（HDM）对于气道上皮Toll样受体4（TLR4）表达及T淋巴细胞分化的影响,以进一步探讨其在哮喘小鼠气道炎症中作用。方法雌性BALB/c小鼠30只随机分为OVA哮喘模型组（OVA组）、HDM组和生理盐水对照组（对照组）。OVA组用卵白蛋白（OVA）致敏与激发建立小鼠哮喘模型,HDM组给予HDM提取液替代OVA致敏与激发,对照组用生理盐水替代OVA。观察小鼠气道及肺组织病理炎症浸润情况,支气管肺泡灌洗液（BALF）中细胞总数及细胞分类计数。ELISA检测小鼠BALF上清中IL-4、IL-5、IL-13、IFN-γ和IL-17的含量。实时荧光定量PCR法测定气道上皮TLR4 mRNA的表达,免疫印迹法测定气道上皮TLR4蛋白的表达。流式细胞技术检测小鼠外周血Th1、Th2及Th17淋巴细胞占CD4＋T淋巴细胞百分率情况。结果 OVA组支气管黏膜下水肿,黏液腺增生,以嗜酸粒细胞为主的炎症细胞浸润;HDM组出现肺泡腔及间质充血,中性粒细胞等炎症细胞浸润;对照组小鼠气道上皮无增厚,无炎症细胞浸润,肺泡壁完整。与OVA组比较,HDM组BALF细胞总数及分类计数除嗜酸粒细胞无显著差异外（P〉0.05）,其余均显著升高（P〈0.05）;HDM组BALF上清中IL-4、IL-5、IL-13及IL-17水平较OVA组明显增高（P〈0.05）,IFN-γ的表达无显著差异（P〉0.05）;HDM组气道上皮TLR4 mRNA及TLR4蛋白的表达明显增高（P〈0.05）,OVA组与对照组差异无统计学意义（P〉0.05）。与OVA组比较,HDM组外周血Th2、Th17细胞显著增高（P〈0.05）,而Th1细胞无明显变化（P〉0.05）。结论 HDM诱导气道上皮TLR4表达增高,使Th2与Th17淋巴细胞活化,气道内炎症细胞浸润,可能在哮喘气道炎症中起重要作用。     

哮喘气道炎症中嗜酸性粒细胞凋亡与IL—5、IL—10关系的研究

目的 动态观察哮喘动物模型气道嗜酸性细胞凋亡在炎症中的意义和调控机理。研究IL-5和IL-10对凋亡的调节作用。方法 卵白蛋白（OVA）腹腔注射与雾化吸入诱发BALB/c小鼠哮喘发作，在激发后0、8、24、48、96小时及7、14天行BAL，ELISA法测定IL-5、IL-10浓度。CD15、CD49d双色标记嗜酸细胞（EOS），流式细胞仪上检测EOS凋亡率。结果 OVA激发后电镜观察显示肺内有明显炎性细胞浸润和细胞凋亡。哮喘组EOS凋亡水平与对照大体相似，EOS凋亡率与IL-10/IL-5比值密切相关。结论 IL-5和IL-10分别上行和下行调节哮喘气道炎症。气道局部有EOS凋亡现象，并受到IL-5、IL-10相互作用的调节。     

槲皮素对支气管哮喘小鼠气道炎症的作用及机制研究

目的 研究槲皮素是否对支气管哮喘小鼠模型气道炎症具有抑制作用及可能的分子机制。方法 通过腹腔注射卵蛋白（OVA）致敏并行雾化激发复制小鼠支气管哮喘模型。将36只BALB/c雌性小鼠随机分为6组,分别为对照组（CON组）、哮喘模型组（OVA组）、槲皮素低剂量组（LOW组）、槲皮素中剂量组（MID组）、槲皮素高剂量组（HIGH组）剂量组、地塞米松阳性对照组（POS组）。对小鼠哮喘症状的程度进行评分;通过ELISA法检测小鼠支气管肺泡灌洗液（BALF）的上清液中白细胞介素-4（IL-4）和IL-5的水平;qRT-PCR检测肺组织miR-155的水平。结果 与CON组比较,OVA组小鼠的哮喘症状评分较高,IL-4、IL-5和miR-155表达水平上调（均P?<0.05）。与OVA组小鼠比较,随着槲皮素药物浓度的升高,槲皮素不同浓度组小鼠的哮喘症状评分下降,IL-4、IL-5和miR-155表达水平降低（均P?<0.05）。结论 槲皮素能改善支气管哮喘小鼠气道炎症,其机制可能与下调IL-4、IL-5和miR-155表达有关。     

Linker for activation of T cells contributes to airway inflammation in an asthmatic mouse model

Background Allergic asthma is associated with airway inflammation and hyperresponsiveness caused by dysregulated production of cytokines secreted by allergen-specific helper T-type 2 （Th2） cells. The linker for activation of T cells （LAT） is a membrane-associated adaptor protein, which has been shown to take part in regulating T cell receptor （TCR） signaling and T cell homeostasis. In this study, we established an asthmatic mouse model to examine the changes in LAT levels during allergic airway disease and the effects of LAT transgenic expression on airway inflammation. Methods T cells from mouse lung tissues were isolated from allergen challenged （ovalbumin （OVA）） and control mice, and the purity of these isolated T cells was examined by fluorescence-activated cell sorter （FACS）. Semi-quantitative RT-PCR and Western blotting were used to detect the expression of the LAT gene and LAT protein, respectively. After an intranasally administered mixture of pCMV-HA-LAT plasmid and Lipofectamine 2000, 24 hours before and 72 hours after allergen challenge, the BALF cell count and the differential cytologies were studied. In addition, IL-4 and IFN-γ levels in the BALF were determined by ELISA, and pathological changes in lung tissues were observed. Results LAT protein and mRNA expression were decreased in lung T cells in a mouse model of allergen-induced airway disease. After intranasal administration of pCMV-HA-LAT, histopathological examination of the lungs showed that intervention with LAT overexpression prevented mice from developing airway inflammation, and the number of total cells, eosinophils, neutrophils, and lymphocytes in the BALF was reduced significantly compared with the OVA sensitized and challenged group. In addition, the Th2 cytokine IL-4 decreased, while the Thl cytokine IFN-γ increased compared to the OVA sensitized and challenged group or the OVA sensitized group plus pCMV-HA treatment. Conclusion This study demonstrates that LAT might effectively diminish Th2 cytokine responses, lung histopathological changes and lung inflammation to allergen challenge in a model of expedmentally induced asthma.     

补肺益肾方对幼龄哮喘豚鼠模型IL-5信号通路的调控机制

目的：观察中药补肺益肾方对幼龄哮喘豚鼠支气管肺泡灌洗液（BALF）中白介素-5（IL-5）水平以及嗜酸粒细胞（ EOS）上白介素-5受体α（ IL-5 R α）mRNA表达的影响,探讨中药补肺益肾方通过IL-5信号通路促进哮喘EOS凋亡的机制。方法24只健康幼龄豚鼠随机分为正常组、模型组、中药组。以卵蛋白致敏激发制备豚鼠哮喘模型,分离豚鼠BALF中的EOS,酶联免疫吸附法（ ELISA）检测BALF中IL-5的含量,TdT介导的dUTP缺口末端标记法（ TUNEL）检测EOS凋亡,原位杂交检测IL-5 RαmRNA表达。结果模型组IL-5水平高于正常组（ P﹤0.01）,中药组IL-5水平低于模型组（ P﹤0.05）。模型组豚鼠EOS凋亡明显减少,中药组EOS凋亡明显高于模型组（ P﹤0.01）。模型组豚鼠EOS表达IL-5 Rα mRNA明显低于正常组（ P﹤0.01）,中药组EOS表达 IL-5 RαmRNA明显增加（ P﹤0.05）。结论中药补肺益肾方可通过降低气道IL-5水平,促进IL-5 RαmRNA表达,来促进EOS凋亡,减轻气道炎症,从而达到防治哮喘的目的。     

色氨酸代谢物调控Th17/Treg分化在小鼠哮喘变应原特异性免疫治疗中的作用及机制研究

目的 对色氨酸代谢物调控Th17/Treg分化在小鼠哮喘变应原特异性免疫治疗中的作用及机制进行研究.方法 将30只BALB/c鼠随机法分为5组:对照组、哮喘组、OVA-SIT组(OVA:鸡卵白蛋白;SIT:变应原特异性免疫治疗)、OVA-SIT+ 1-MT组(1-MT:IDO抑制剂,1-甲基色氨酸),OVA-SIT+1-MT+ KYN组(KYN:色氨酸代谢产物,犬尿氨酸).哮喘组:第0、7d予OVA致敏,第6周每天予1％OVA雾化激发,50 d予10％ OVA加强激发;OVA-SIT组:第4周每天予大剂量OVA皮下注射,余同哮喘组;OVA-SIT+ 1-MT组:第4周每天在腹腔内注入1-MT,1h后予大剂量OVA皮下注射h,余同哮喘组;OVA-SIT+ 1-MT+ KYN组:第3周每天加入1-MT,第4周每天加入KYN,末次加入KYN后1h予大剂量OVA行免疫治疗,余同哮喘组.末次激发6h内检测气道高反应性;对支气管肺泡灌洗液(BALF)进行细胞计数分析;ELISA检测血清IgE及BALF中IL-5、IL-10、IL-17;流式细胞技术检测脾脏CD4+RORγt+T及CD4+Foxp3+T细胞分化情况.结果 OVA-SIT+1-MT+KYN组较OVA-SIT+1-MT组酸性粒细胞浸润减少,炎症反应明显减轻.前者BALF中Il-5为74.8 ～ 86.8(83.48±6.02) pg/mL,IL-17为33.8～46.5(38.72 ±4.61) pg/mL,CD4+ RORγt+T细胞为2.45 ～2.82(2.60±0.14)％,CD4+ Foxp3+T细胞为7.83 ～9.09(8.36 ±0.53)％;后者BALF中Il-5为240.3～285.1 (259.65±16.27) pg/mL,IL-17为55.2 ～ 65.8(59.97±3.76) pg/mL,CD4+ RORγt+T细胞为4.31 ～5.34(4.94±0.38)％,CD4+Foxp3+T细胞为5.93～6.59(6.33 ±0.28)％,因此OVA-SIT+ 1-MT+ KYN组中Il-5、IL-17细胞因子以及脾脏中CD4+ RORγt+T细胞均明显低于OVA-SIT+ 1-MT组,差异均有统计学意义(P＜0.01),而前组脾脏中CD4+ Foxp3+T细胞水平明显高于后者,差异有统计学意义(P＜0.01).结论 色氨酸代谢产物有助于特异性免疫治疗减轻气道炎症作用,其机制与通过调控Th17及Treg分化有关.     

CD8+CD28-T细胞在哮喘小鼠发病机制中的作用及地塞米松对其的影响

目的 探讨CD8+CD28-T细胞在哮喘发病机制中的作用及地塞米松对该细胞的影响.方法 30只BALB/c小鼠随机分为哮喘组、地塞米松组、正常对照组,各10只.哮喘组和地塞米松组给予卵白蛋白致敏后雾化吸入卵白蛋白溶液,地塞米松组每次雾化吸入前腹腔注射地塞米松1 mg/kg,各组分别于末次雾化激发后测定小鼠的气道反应性;对支气管肺泡灌洗液(BALF)行细胞总数、嗜酸性粒细胞(EOS)计数;取肺组织作HE染色病理切片;测BALF中IgE含量;流式细胞仪检测小鼠血、BALF中CD8+CD28-T细胞占淋巴细胞百分比;分析BALF中IgE、EOS计数与血液中CD8+CD28-T细胞百分比的相关性.结果 哮喘组、地塞米松组气道反应性明显高于正常对照组.哮喘组BALF中细胞总数和EOS计数分别为(5.56±4.06)× 102/L和(3.29±2.23)× 102/L,均明显高于地塞米松组[(2.59±1.69)× 102/L,P=0.044和(1.11±0.73)×102/L,P=0.008]及正常对照组[(0.91±0.65)×102/L,P=0.003和(0.43±0.37)× 102/L,P=0.001)];而后两组之间差异均无统计学意义(均P>0.05).哮喘组、地塞米松组、正常对照组BALF中IgE含量分别为(23.85±5.97)g/L、(13.15±2.22)g/L、(6.54±1.03)g/L,三组间差异有统计学意义(F=38.558,P=0.000).哮喘组、地塞米松组、正常对照组CD8+CD28-T细胞百分比在外周血中分别为(18.68±4.12)%、(13.43±2.90)%、(8.43±4.60)%;在BALF中分别为(1.25±0.40)%、(0.66±0.49)%、(0.21±0.19)%,组间差异均有统计学意义(F=11.837,P=0.001;F=12.885,P=0.000).哮喘组BALF中IgE含量和EOS计数与外周血中CD8+CLY28-T细胞百分比均呈正相关(r=0.864,P=0.012和r=0.804,P=0.029).结论 CD8+CD28-T细胞数量与哮喘小鼠气道炎症有明显相关性,地塞米松可有效抑制哮喘气道炎症并可能抑制了CD8+CD28-T细胞的表达和功能.

Abstract：

Objective To explore whether or not CD8+ CD28- T cell play a pathogenic role in asthma and detect the effects of dexamethasone ( DXM ). Methods A total of 30 mice were randomly divided into 3 groups: asthmatic group, DXM group and control group ( n = 10 each). The asthmatic and DXM groups were sensitized twice and inhaled ovalbumin. The DXM Group received an intraperitoneal injection of DXM lmg/kg before inhaling ovalbumin. After successful modeling, 3 mice were selected randomly from each group to measure the airway responsiveness. Also a bronchoalveolar lavage cytological study was performed and lung tissue sections were prepared for histopathologic examination to evaluate the airway inflammation. The content of IgE in bronchoaleolar lavage fluid ( BALF) was detected with a murine IgE ELISA kit. And the fractions of CD8 + CD28- T cell of peripheral blood and BALF were tested by flow cytometry to analyze the correlation between IgE, eosinophils ( EOS) of BALF and CD8 + CD28 - T cell of blood. Results The airway hyperresponsiveness in asthmatic and DXM groups were significantly higher than that in the control group. The number of total cells and EOS of BALF in the asthmatic group [ ( 5. 56 ±4. 06) × 102/L; (3. 29 ±2. 23) × 102/L] were significantly higher than that in control group [ (0. 91 ±0.65)×102/L, P = 0.003; (0.43 ±0.37) × 102/L, P = 0.001] and DXM group [(2.59 ±1.69) ×102/L, P =0.044; (1. 11 ±0.73) ×l02/L, P = 0.008]; while the DXM group was insignificantly higher than the control group (P=0. 234, P=0. 363). There were significant differences in the contents of IgE of BALF for the asthmatic, DXM and control groups [ (23. 85 ±5. 97) g/L, (13. 15 ±2.22) g/L, (6.54±1. 03) g/L, F = 38. 558, P = 0. 000 ] . The percentages of CD8 + CD28- T cell in peripheral blood in asthmatic and DXM groups [ (18. 68 ±4. 12)% and ( 13.43 ± 2. 91) % ] were significantly higher than those in control mice [ (8. 43 ± 4. 60) % , both P < 0. 05 ]. The percentages of CD8 + CD28 - T cell of BALF in asthmatic group and DXM group [(1.25±0. 40)% and (0. 66 ± 0. 49) % ] were also significantly higher than those in control mice [ (0. 21 ± 0. 19) % , both P < 0. 05 ]. The percentages of CD8 + CD28 - T cell of blood and BALF in the DXM mice were significantly lower than those in asthmatic group. The correlations between IgE ( r = 0. 864, P = 0. 012), EOS ( r = 0. 804, P = 0.029) and CD8 + CD28- T cell were significant. Conclusion The fraction of CD8 + CD28- T cell is closely correlated with the inflammation of asthmatic airway. The airway hyperresponsiveness and inflammation in asthmatic mice may be relieved by DXM through its effect of inhibiting the expression of CD8 + CD28- T cell.     

白细胞介素18对豚鼠哮喘模型气道炎症作用的实验观察

目的观察白细胞介素18(IL-18)对豚鼠哮喘模型气道炎症的作用。方法采用卵蛋白(OVA)腹腔注射致敏加雾化吸入激发的方法复制豚鼠哮喘模型。30只豚鼠按随机数字法分成3组(每组10只)进行处理,分别为哮喘模型组(A组)、模型对照组(B组)和IL-18干预组(C组)。光镜下检测各组豚鼠支气管肺泡灌洗液(BALF)中炎症细胞计数及分类,用酶联免疫吸附法测定BALF中Th1细胞因子IFN-γ、IL-2和Th2细胞因子IL-4、IL-5浓度,并进行3组之间的比较。结果豚鼠BALF中嗜酸粒细胞(EOS)个数A组、B组、C组分别为(98±58)×106/L、(12±10)×106/L、(29±10)×106/L,A组与B组、C组比较差异有统计学意义(P<0.01);中性粒细胞个数A组与B组、C组比较差异有统计学意义(P均<0.05)。IFN-γ和IL-2浓度A组与B组比较差异有统计学意义(P<0.05),与C组比较差异亦有统计学意义(P均<0.01)。IL-4浓度A组与B组、C组比较差异有统计学意义(P均<0.05);IL-5浓度A组与B组、C组比较差异有统计学意义(P<0.01)。结论IL-18可通过调节Th1/Th2细胞因子的平衡而达到控制哮喘气道炎症的作用。     

皮内注射灭活卡介苗对哮喘大鼠CD4+CD25+Treg细胞数量和CTLA-4 mRNA表达的影响

目的:探讨皮内注射灭活卡介苗(BCG)后哮喘大鼠CD4⁺CD25⁺Treg细胞数量、细胞毒性T 淋巴细胞抗原4(CTLA-4)的表达及血清转移生长因子β(TGF-β)水平变化,阐明灭活BCG对CD4⁺CD25⁺Treg细胞数量及CTLA-4 mRNA表达的影响。方法:30只健康雄性成年SD大鼠随机分为:对照组、模型组和BCG组,每组10只;除对照组外,模型组和BCG组大鼠采用卵清蛋白(OVA)致敏3周;再激发6周,构建大鼠慢性哮喘模型。BCG组大鼠在致敏前3 d开始皮内注射BCG,共9周。各组大鼠均行气道高反应性检测,检测CD4⁺CD25⁺Treg细胞数量及CTLA-4 mRNA相对表达水平,行肺泡灌洗液(BALF)中细胞总数及嗜酸性粒细胞(EOS)百分比计数,检测各组大鼠血清中TGF-β水平。结果:模型组大鼠BALF中细胞总数及EOS百分比明显高于对照组(P<0.05),BCG组明显低于模型组(P<0.05)。组胺质量浓度从0.32 g·L^-1开始,模型组和BCG组大鼠气道阻力明显高于对照组 (P<0.05);组胺质量浓度从0.64 g·L^-1开始, BCG组大鼠气道阻力明显低于模型组(P<0.05)。模型组大鼠CD4⁺CD25⁺Treg细胞/CD4⁺细胞数量明显低于对照组(P<0.05),BCG组明显高于模型组(P<0.05)。模型组大鼠CTLA-4 mRNA相对表达水平明显低于对照组(P<0.05),BCG组明显高于模型组(P<0.05)。模型组大鼠血清TGF-β水平明显低于对照组(P<0.05),BCG组明显高于模型组(P<0.05)。结论:灭活BCG改善气道炎症和气道阻力作用可能与恢复CD4⁺CD25⁺Treg细胞数量及功能有关联。     

IL-17在哮喘小鼠模型中表达及其对肥大细胞IL-6分泌的影响

目的 :研究白细胞介素(interleukin,IL)-17在哮喘小鼠模型中的表达,观察其对肥大细胞IL-6分泌的影响。方法:BALB/c小鼠随机分为对照组和哮喘组,分别用等量磷酸盐缓冲液(phosphate buffer solution,PBS)和卵清蛋白(ovalbumin,OVA)干预,检测肺泡灌洗液(bronchoalveolar lavage fluid,BALF)中细胞总数及嗜酸性粒细胞(eosnophils,EOS)数验证模型的成功建立。应用逆转录-聚合酶链反应法、酶联免疫吸附实验(enzyme-linked immunosorbent assay,ELISA)检测两组小鼠肺组织中IL-17m RNA、BALF及血清中IL-17的表达差异。细胞实验分为对照组和IL-17组,分别予等量培养基和IL-17干预小鼠肥大细胞株(P815)后收集上清,用ELISA检测IL-6的水平。结果 :哮喘组BALF中细胞总数及EOS计数较对照组显著升高(P<0.05),模型建立成功。哮喘组肺组织中IL-17 m RNA、BALF及血清中IL-17表达较正常组显著升高(P<0.05)。细胞水平的研究发现IL-17组P815上清中IL-6表达较正常组显著升高(P<0.05)。结论 :IL-17在OVA诱导哮喘小鼠模型中表达升高。IL-17刺激肥大细胞分泌IL-6,可能在哮喘的发病中起促进作用。     

Protective Effect of Emodin against Airway Inflammation in the Ovalbumin-Induced Mouse Model

Objective: To investigate whether emodin exerts protective effects on mouse with allergic asthma. Methods: A mouse model of allergic airway inflammation was employed. The C57BL/6 mice sensitized and challenged with ovalbumin (OVA) were intraperitoneally administered 10 or 20 mg/kg emodin for 3 days during OVA challenge. Animals were sacrificed 48 h after the last challenge. Inflammatory cell count in the bronchoalveolar lavage fluid (BALF) was measured. The levels of interleukin (IL)-4, IL-5, IL-13 and eotaxin in BALF and level of immunoglobulin E (IgE) in serum were measured with enzyme-linked immuno sorbent assay kits. The mRNA expressions of IL-4, IL-5, heme oxygenase (HO)-1 and matrix metalloproteinase-9 (MMP- 9) were determined by real-time quantitative polymerase chain reaction. Results: Emodin induced significant suppression of the number of OVA-induced total inflammatory cells in BALF. Treatment with emodin led to significant decreases in the levels of IL-4, IL-5, IL-13 and eotaxin in BALF and total IgE level in serum. Histological examination of lung tissue revealed marked attenuation of allergen-induced lung eosinophilic inflammation. Additionally, emodin suppressed IL-4, IL-5 and MMP-9 mRNA expressions and induced HO-1 mRNA expression. Conclusion: Emodin exhibits anti-inflammatory activity in the airway inflammation mouse model, supporting its therapeutic potential for the treatment of allergic bronchial asthma.