乳胶致小鼠气道炎症的研究

目的：以乳胶为致敏原，建立具有哮喘主要特征的小鼠模型，研究乳胶与气道炎症之间的关系。方法：乳胶腹腔注射与滴鼻诱发BALB／C小鼠气道炎症，在激发后2，4小时行支气管肺泡灌洗液(BALF)细胞计数分类、肺组织病理检查、血清总IgE及乳胶特异性IgE(sIgE)测定并检测IL-5、IFN-γ的表达。结果：乳胶诱发后，实验组小鼠BALF中细胞总数及嗜酸粒细胞百分比升高；肺组织病理切片示支气管上皮增生、脱落，粘液腺分泌现象，支气管痉挛、收缩，炎症细胞浸润；血清总IgE及乳胶sIgE水平升高；BALF及肺组织局部IFN-γ减少，IL-5增高。结论：用乳胶蛋白作为致敏原，采用腹腔致敏与多次滴鼻激发可使BALB/C小鼠发生气道炎症，具有与变应原诱导的人类哮喘迟发反应相一致的主要特征：气道变应性炎症；外周血IgE浓度升高；肺组织中Th2型CK表达占优势。     

Thl7淋巴细胞在哮喘小鼠气道炎症中的初步研究

目的:初步探索Th17细胞及其分泌的炎症介质在哮喘小鼠气道炎症中的作用机制.方法:20只小鼠随机均分为哮喘组和正常对照组.哮喘组用卵白蛋白(OVA)致敏与激发建立小鼠哮喘模型.正常对照组致敏与激发均以生理盐水代替.HE染色观察小鼠气道及肺组织病理变化;光学显微镜下观察小鼠支气管肺泡灌洗液(BALF)中细胞分类及计数;酶联免疫吸附试验(ELISA)检测小鼠BALF上清中IL-4、IL-5、IL-13、IFN-γ及IL-17的含量,流式细胞技术(FCM)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:哮喘组小鼠BALF中细胞总数和中性粒细胞、嗜酸性粒细胞、淋巴细胞百分率均显著高于对照组(P<0.05),BALF上清中IL-4、IL-5、IL-13及IL-17的水平显著增高(P<0.05),而IFN-γ差异无统计学意义(P>0.05),外周血Th2、Th17细胞明显增高(P<0.05),而Th1细胞无明显变化.结论:Th17细胞及其分泌的炎症介质可促进中性粒细胞及嗜酸性粒细胞在气道内聚集,加重哮喘气道炎症,可能与哮喘气道重塑密切相关.     

Th17淋巴细胞在哮喘小鼠气道炎症中的初步研究

目的:初步探索Th17细胞及其分泌的炎症介质在哮喘小鼠气道炎症中的作用机制。方法:20只小鼠随机均分为哮喘组和正常对照组。哮喘组用卵白蛋白(OVA)致敏与激发建立小鼠哮喘模型。正常对照组致敏与激发均以生理盐水代替。HE染色观察小鼠气道及肺组织病理变化;光学显微镜下观察小鼠支气管肺泡灌洗液(BALF)中细胞分类及计数;酶联免疫吸附试验(ELISA)检测小鼠BALF上清中IL-4、IL-5、IL-13、IFN-γ及IL-17的含量,流式细胞技术(FCM)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:哮喘组小鼠BALF中细胞总数和中性粒细胞、嗜酸性粒细胞、淋巴细胞百分率均显著高于对照组(P<0.05),BALF上清中IL-4、IL-5、IL-13及IL-17的水平显著增高(P<0.05),而IFN-γ差异无统计学意义(P>0.05),外周血Th2、Th17细胞明显增高(P<0.05),而Th1细胞无明显变化。结论:Th17细胞及其分泌的炎症介质可促进中性粒细胞及嗜酸性粒细胞在气道内聚集,加重哮喘气道炎症,可能与哮喘气道重塑密切相关。     

菠萝蛋白酶诱导小鼠急性过敏性气道炎症的作用研究

探讨菠萝蛋白酶诱导小鼠急性过敏性气道炎症中2型固有淋巴细胞(group 2innate lymphoid cell,ILC2)及相关细胞因子的变化及意义。对未致敏BALB/c雌性小鼠在第1天和第3天给予菠萝蛋白酶滴鼻,ELISA检测12h内小鼠肺组织匀浆上清中IL-33变化,5d后处死小鼠,肺组织切片病理观察,瑞氏染色计数BALF中嗜酸性粒细胞含量,流式检测肺组织中ILC2数量变化,ELISA检测BALF中IL-5、IL-13水平。结果显示,菠萝蛋白酶诱导气道上皮细胞产生IL-33,3h时开始,6h时达高峰;菠萝蛋白酶滴鼻小鼠肺组织切片显示大量炎性细胞浸润和杯状细胞黏液分泌增加,BALF中嗜酸性粒细胞比例增加,IL-5和IL-13含量增加,流式检测肺组织中ILC2数量增多。研究表明,菠萝蛋白酶刺激小鼠气道上皮细胞释放IL-33,引起小鼠肺ILC2活化增殖并分泌大量Th2型细胞因子,引起嗜酸性粒细胞浸润等急性过敏性气道炎症表现,提示ILC2促进早期急性过敏性气道炎症的发生。     

呼吸道合胞病毒不同感染时间对过敏性气道炎症反应的作用研究

目的:探讨呼吸道合胞病毒(RSV)不同感染模式对花粉诱导的气道过敏性炎症反应的影响。方法:用花粉抽提物JCP致敏BALB/c鼠,在致敏前或致敏后的不同时间点经鼻粘膜感染RSV。HE染色法分类肺泡灌洗液中炎症细胞类型并计数其数量;ELISA法检测血清中过敏原特异性抗体含量;细胞因子检测试剂盒检测肺组织细胞培养上清中IL-17和IL-5水平。结果:与对照JCP组相比,JCP致敏前RSV感染组肺组织炎症细胞浸润程度明显减轻,炎症细胞总数及嗜酸性粒细胞数量明显下降;血清IgE总量及JCP特异性IgE和IgG1抗体水平显著降低;肺组织淋巴细胞IL-17分泌水平升高,而IL-5分泌减少。与致敏前RSV感染模式不同,致敏后RSV感染无论是对JCP诱导的气道过敏性炎症反应,亦或对血清抗体水平和细胞因子分泌活性均无明显影响。结论:RSV不同感染模式对JCP诱导的过敏性气道炎症具有不同的作用特点,致敏前RSV感染降低过敏原诱导的气道炎症反应。     

雾化吸入灭活草分支杆菌减轻哮喘小鼠气道炎症及对Toll样受体2表达的影响

目的研究雾化吸入灭活草分支杆菌对支气管哮喘小鼠气道炎症及肺组织细胞因子分泌的影响,探讨Toll样受体2(TLR2)表达在雾化吸入灭活草分支杆菌防治支气管哮喘中的作用。方法将24只雄性Balb/c小鼠按随机数字表法分为3组,每组8只:正常对照组(A)、哮喘模型组(B)、干预组(C)。卵清蛋白(OVA)致敏制小鼠支气管哮喘模型。C组在每次卵蛋白激发前给予雾化吸入草分枝杆菌治疗,每天1次。各组动物处死后提取肺组织和支气管肺泡灌洗液(BALF)。进行病理HE染色、AB-PAS染色观察支气管肺炎症和气道粘液分泌情况,并行半定量分析。BALF中炎症细胞计数,检测BALF中IL-4、IL-10、IFN-γ水平。实时定量PCR检测肺组织TLR2 mRNA表达水平。结果干预组BALF中IL-4分泌减少,IL-10、IFN-γ增加(P<0.05),BALF中嗜酸性粒细胞比例低于模型组,气道炎症病变较模型组减轻,肺组织TLR2 mRNA表达水平较模型组显著升高(P<0.05)。结论吸入草分枝杆菌能减轻支气管哮喘小鼠气道炎症,其效应与调节肺内细胞因子分泌有关。草分枝杆菌可能通过上调TLR2基因的表达调节支气管哮喘的免疫失衡。     

抗IgE抗体对哮喘模型小鼠的气道高反应和Th2类细胞因子的影响

目的探讨抗IgE抗体在哮喘小鼠模型中对气道高反应及Th2类细胞因子变化的影响及其可能机制。方法雌性Balb/c小鼠30只随机分成3组,即正常对照组、哮喘模型组和抗IgE抗体干预组。分别采用酶联免疫吸附法(ELISA)和蛋白质印迹检测支气管肺泡灌洗液(BALF)和肺组织中IL-4、IL-5、IL-13、IL-10、TGF-β1含量以及蛋白表达。应用小鼠肺功能仪检测气道阻力的变化。结果抗IgE抗体治疗组与哮喘模型组比较气道阻力明显降低。哮喘模型组小鼠BALF和肺组织中IL-4、IL-5、IL-13、IL-10、TGF-β1含量和蛋白表达明显升高,与正常对照组比较,显著差异(P<0.05)。抗IgE抗体干预组小鼠BALF和肺组织中IL-4、IL-5、IL-13含量和蛋白表达水平均明显降低;IL-10、TGF-β1含量和蛋白表达水平上升不明显,与哮喘模型组比较,没有显著差异(P>0.05)。结论抗IgE抗体对哮喘小鼠的治疗作用,其机制可能与调节Th2细胞所分泌的炎症细胞因子有关。     

蟑螂变应原诱导小鼠肺部变应性炎症动物模型的研究

目的建立美洲大蠊提取液（CAE）诱导的小鼠变应性气道炎症动物模型。方法24只Balb／c小鼠随机分为正常对照组（C组）和美洲大蠊粗浸液2个剂量组：低剂量50μg组（A组）、高剂量100μg组（B组），8只／组。通过HE染色和PAS染色观察小鼠肺部炎症和黏液分泌；观察支气管肺泡灌洗液中细胞总数和细胞分类；用酶联免疫吸附试验检测BALF、脾细胞培养上清液的细胞因子和血清CAE特异的IgE、IgG1、IgG2a抗体。结果A、B组与对照组C组比较，可诱导肺组织出现明显的气道变态反应性炎症，肺组织炎症病理评分有显著性差异（P〈0．01）；BALF中的细胞总数、EOS计数、中性粒细胞数、IL-4，血清抗原特异性IgE抗体、IgG1抗体和脾细胞分泌IL-4均显著高于正常对照组C组（P〈0．01）；且BALF中的嗜酸性粒细胞计数和IL-4水平与美洲大蠊粗浸液的使用剂量有关（P〈0．01）。结论美洲大蠊提取液能成功建立小鼠变态反应气道炎症动物模型，且呈剂量依赖性，高剂量能更有效诱导气道变态反应性炎症。     

促红细胞生成素对哮喘小鼠肺组织VEGF及ICAM-1表达的影响

目的探讨促红细胞生成素对哮喘小鼠肺组织血管内皮生长因子(VEGF)及细胞间黏附分子(ICAM)-1的影响。方法 36只BALB/c小鼠,雌雄不限,随机分为对照组、哮喘组和促红细胞生成素组,卵蛋白致敏的方法制备哮喘小鼠模型。用乙酰甲胆碱行支气管激发试验,测定各组小鼠气道阻力的变化;收集支气管肺泡灌洗液(BALF),进行细胞总数计数及嗜酸性粒细胞计数,免疫组织化学和Western blot方法检测各组小鼠肺组织VEGF与ICAM-1的表达。结果促红细胞生成素能够降低哮喘小鼠的气道阻力,降低BALF中细胞总数及嗜酸粒细胞数(P0.01)。免疫组织化学和Western blot的光密度值分析结果显示,促红细胞生成素组小鼠肺组织VEGF与ICAM-1蛋白表达的平均光密度值显著低于哮喘组小鼠(P0.01)。结论促红细胞生成素可降低哮喘小鼠气道阻力及肺内炎症,与下调VEGF与ICAM-1的蛋白表达相关。     

艾蒿花粉诱导豚鼠过敏反应

目的：研究艾蒿花粉粗提物（MPE）和其主要成分之一artemisia vulgaris 1（Art V1）能否诱导豚鼠过敏反应,为艾蒿花粉过敏症研究建立动物模型。方法: 艾蒿花粉粗提物或Art V1混悬于佐剂氢氧化铝凝胶中,每间隔10 d致敏豚鼠1次,共4次,然后以艾蒿花粉粗提物或Art V1抗原滴鼻诱发鼻炎症状。气道高反应性(AHR)、炎症细胞和肺组织病理的观察于Art V1气雾攻击5 d后,以乙酰甲胆碱（Mch）气雾吸入激发AHR,测定气道阻力和动态肺顺应性,计数和分类计数支气管肺泡灌洗液（BALF）中的炎症细胞,观察肺组织病理学改变。 结果: Art V1组豚鼠在抗原激发下喷嚏次数和抓鼻次数显著增加,吸入Mch后气道阻力明显增加,动态肺顺应性明显降低,Mch气雾吸入可激发AHR;MPE组豚鼠喷嚏次数有所增加,气道反应性有所升高;两组BALF和病理切片均显示明显的嗜酸性粒细胞和中性粒细胞浸润。结论: 艾蒿花粉粗提物和其主要成分Art V1均能诱导豚鼠过敏反应,Art V1致敏效果明显优于艾蒿粗提物。该模型的建立有利于过敏性疾病机制和治疗新药的研究。     

薯蓣皂苷减轻卵清蛋白诱导的过敏性哮喘小鼠的气道炎症

目的探讨薯蓣皂苷对卵清蛋白(ovalbumin,OVA)诱导的过敏性哮喘小鼠中过敏性支气管炎的影响及机制。方法24只小鼠随机分为对照组、OVA组、OVA+30 mg/kg薯蓣皂苷组和OVA+60 mg/kg薯蓣皂苷组,每组纳入6只小鼠。全自动生化仪检测各组支气管肺泡灌洗液(bronchoalveolar lavage fluid,BALF)中嗜中性粒细胞、嗜酸性粒细胞和单核细胞的数量;ELISA法检测BALF中促炎因子IL-1β、IL-4、IL-5和TNF-α的含量;PAS染色法观察肺组织黏液分泌情况并对黏液分泌程度进行评分;免疫组化法观察肺组织p-NF-κB p65的表达和分布情况;Western blotting法检测肺组织中p-IκB和NF-κB p65的蛋白表达水平。结果薯蓣皂苷可降低过敏性哮喘小鼠BALF中炎性细胞数量,同时降低BALF中促炎因子IL-1β、IL-4、IL-5和TNF-α的水平以及肺部黏液的分泌和NF-κB的活化水平。结论薯蓣皂苷能减轻过敏性哮喘小鼠的气道炎症,且其抗炎作用与抑制NF-κB活化有关。     

Effect of ageing on pulmonary inflammation, airway hyperresponsiveness and T and B cell responses in antigen-sensitized and -challenged mice

BACKGROUND: The effect of ageing on several pathologic features of allergic asthma (pulmonary inflammation, eosinophilia, mucus hypersecretion), and their relationship with airway hyperresponsiveness (AHR) is not well characterized. OBJECTIVE: To evaluate lung inflammation, mucus metaplasia and AHR in relationship with age in murine models of allergic asthma comparing young and older mice. METHODS: Young (6 weeks) and older (6, 12, 18 months) BALB/c mice were sensitized and challenged with ovalbumin (OVA). AHR and bronchoalveolar fluid (BALF), total inflammatory cell count and differential were measured. To evaluate mucus metaplasia, quantitative PCR for the major airway mucin-associated gene, MUC-5AC, from lung tissue was measured, and lung tissue sections stained with periodic acid-Schiff (PAS) for goblet-cell enumeration. Lung tissue cytokine gene expression was determined by quantitative PCR, and systemic cytokine protein levels by ELISA from spleen-cell cultures. Antigen-specific serum IgE was determined by ELISA. RESULTS: AHR developed in both aged and young OVA-sensitized/challenged mice (OVA mice), and was more significantly increased in young OVA mice than in aged OVA mice. However, BALF eosinophil numbers were significantly higher, and lung histology showed greater inflammation in aged OVA mice than in young OVA mice. MUC-5AC expression and numbers of PAS+ staining bronchial epithelial cells were significantly increased in the aged OVA mice. All aged OVA mice had increased IL-5 and IFN-gamma mRNA expression in the lung and IL-5 and IFN-gamma protein levels from spleen cell cultures compared with young OVA mice. OVA-IgE was elevated to a greater extent in aged OVA mice. CONCLUSIONS: Although pulmonary inflammation and mucus metaplasia after antigen sensitization/challenge occurred to a greater degree in older mice, the increase in AHR was significantly less compared with younger OVA mice. Antigen treatment produced a unique cytokine profile in older mice (elevated IFN-gamma and IL-5) compared with young mice (elevated IL-4 and IL-13). Thus, the airway response to inflammation is lessened in ageing animals, and may represent age-associated events leading to different phenotypes in response to antigen provocation.     

T-bet基因转染对哮喘小鼠气道炎症的影响

目的： 观察气道内T-bet基因转染对哮喘小鼠气道炎症的影响。方法: C57BL/6小鼠40只,随机分为4组,每组10只,分别为正常对照组（A组）、哮喘模型组（B组）、空质粒干预组(C组) 和T-bet质粒干预组(D组)。卵白蛋白(OVA) 抗原溶液腹腔注射致敏,滴鼻造模。正常对照组用生理盐水代替OVA,空质粒干预组和T-bet质粒干预组OVA激发48 h前,分别经鼻滴入50 μg空质粒和重组T-bet质粒。观察各组实验小鼠的肺组织炎症以及BALF中各类炎症细胞以及IL-4、IFN-γ水平的变化。 结果: Western blotting检测发现,小鼠气道转染pcDNA3-T-bet质粒48 h后肺组织T-bet蛋白表达显著增加。pcDNA3-T-bet质粒转染能较好抑制给药后48 h OVA激发的哮喘小鼠气道炎症（包括炎症细胞浸润,上皮细胞损伤、黏液分泌、血管壁水肿及管腔缩窄）;下调小鼠BALF中Th2因子IL-4并上调Th1因子IFN-γ水平。 结论: 气道内转染T-bet质粒能有效改善哮喘小鼠的气道炎症。     

特异性免疫治疗对哮喘小鼠的作用及机制的初步研究

目的　探讨特异性免疫治疗对哮喘小鼠的作用及其可能机制。方法　通过卵蛋白 (OVA)皮下注射的方法对致敏小鼠进行特异性免疫治疗 ,观察肺组织病理、支气管肺泡灌洗液 (BALF)细胞计数及分类、ELISA检测血清OVA特异性IgE(sIgE)及脾脏T淋巴细胞IL 2和IL 4的分泌 ,3H TdR掺入法检测T淋巴细胞的增殖反应 ,并与OVA致敏及激发的哮喘小鼠相比较。结果　哮喘特异性免疫治疗明显抑制小鼠肺组织炎症病理改变 ;BALF中细胞总数及嗜酸性粒细胞 (EOS)数显著减少 (P <0 .0 5 ) ;血清sIgE显著降低 (P <0 .0 5 ) ;T淋巴细胞IL 2和IL 4的分泌显著降低 (P <0 .0 5 ) ;T淋巴细胞对OVA的特异性刺激的反应显著降低 (P <0 .0 5 )。结论　特异性免疫治疗可显著抑制哮喘小鼠的炎症反应 ;诱导T淋巴细胞无能可能是特异性免疫治疗减轻哮喘相关炎症反应的机制之一     

羌活提取物对哮喘小鼠Thl/Th2细胞平衡的影响及其对p38信号通路的作用

目的 探讨羌活提取物（EN）对哮喘小鼠Thl/Th2细胞平衡的影响,以及p38信号通路在其中的作用。 方法 60只雄性清洁级BABL/c小鼠,随机分为6组,每组10只,分别为正常对照组;卵蛋白(OVA)哮喘组;羌活低剂量组;羌活高剂量组、SB203580组和地塞米松组。在末次激发24 h后小鼠肺组织行HE染色。分别用ELISA检测支气管肺泡灌洗液 (BALF)中白细胞介素（IL）-4、IL-5、IL-13和γ-干扰素（IFN-γ）含量以及Western blotting检测肺组织IL-4、IFN-γ、P38蛋白表达。
结果 哮喘组小鼠与对照组小鼠相比较,BALF中炎症细胞计数、IL-4、IL-5、IL-13水平增高,而IFN-γ的表达明显降低(P<0.05),肺部炎症浸润明显(P<0.05);肺组织IL-4和磷酸化P38蛋白表达水平显著高于对照组(P<0.05),而肺组织IFN-γ的表达明显低于对照组(P<0.05)。羌活低、高剂量组、SB203580组和地塞米松组与哮喘模型组相比较,BALF中炎症细胞计数、IL-4、IL-5、IL-13浓度以及肺组织IL-4和磷酸化P38蛋白表达水平均显著降低(P<0.05);肺部炎症明显减轻(P<0.05);BALF和肺组织中IFN-γ明显升高(P<0.05)。 结论 羌活提取物具有明显的抗哮喘作用,其机制可能是通过抑制P38信号通路,影响Thl/Th2细胞平衡实现的。     

Repeated aerosol allergen exposure suppresses inflammation in B-cell-deficient mice with established allergic asthma

BACKGROUND: Repeated allergen administration is a well-established therapeutic strategy for desensitizing patients with allergic disease. Similarly, repeated inhalation of antigen by mice with established allergen-induced asthma suppresses allergic inflammation. The mechanisms underlying antigen-dependent suppression of allergic immune responses remain unknown. In previous studies, we found that repeated aerosol antigen challenges in sensitized mice reduced eosinophils while increasing plasma cells and antibody in the lungs. We sought to test whether plasma cells and antibody played a role in suppression of allergic disease. METHODS: We primed wild-type and B-cell-deficient (microMT) mice with 25 microg ovalbumin (OVA) precipitated in alum on days 0 and 5, nebulized weekly with 1% OVA, 1 h, twice daily, for up to 6 weeks, and assessed lung inflammation, mucus hypersecretion, and IgE/IgG1. RESULTS: Kinetic studies revealed that initial aerosol exposure induced high numbers of eosinophils, lymphocytes, and macrophages within lung infiltrates and increased mucus production in wild-type mice. After 3-4 weeks of antigen exposure, eosinophils diminished while lymphocytes, plasma cells, and macrophages and mucus hypersecretion increased. However, by 6 weeks, lung inflammation and mucus hypersecretion were dramatically reduced. In contrast, repeated aerosol challenges maintained OVA-specific IgG1 and IgE production. Repeated aerosol antigen challenges in microMT mice resulted in reduced lung inflammation and mucus hypersecretion and the development of smooth muscle hypertrophy of the pulmonary microvasculature. CONCLUSIONS: B cells and antibody do not appear to play a role in antigen-dependent suppression of allergic responses in mice.     

SP600125 promotes resolution of allergic airway inflammation via TLR9 in an OVA-induced murine acute asthma model

Backgroundc-Jun N-terminal kinase (JNK) relays extracellular stimuli through phosphorylation cascades that lead to various cell responses. In the present study, we aimed to investigate the effect of the JNK inhibitor SP600125 on the resolution of airway inflammation, and the underlying mechanism using a murine acute asthma model.MethodsFemale C57BL/6 mice were sensitized with saline or ovalbumin (OVA) on day 0, and challenged with OVA on day 14–20. Meanwhile, some of the mice were treated with SP600125 (30 mg/kg) intraperitoneally 2 h before each challenge. The airway inflammation was evaluated by counting the numbers of various types of inflammatory cells in bronchoalveolar lavage fluid (BALF), histopathology, cytokines production and mucus secretion in individual mouse. In addition, we analyzed the protein levels of phosphorylated JNK and TLR9 in the lung tissues.ResultsSP600125 markedly reduced the invasion of inflammatory cells into the peribronchial regions, and decreased the numbers of eosinophils, monocytes, neutrophils and lymphocytes in BALF. SP600125 also reduced the level of plasma OVA-specific IgE, lowered the production of pro-inflammatory cytokines in BALF and alleviated mucus secretion. Meanwhile, SP600125 inhibited OVA-induced, increased expression of p-JNK and TLR9 in the lung tissues.ConclusionsCollectively, our data demonstrated that SP600125 promoted resolution of allergic airway inflammation via TLR9 in an OVA-induced murine acute asthma model. The JNK-TLR9 pathway may be a new therapeutic target in the treatment for the allergic asthma.     

卵清蛋白雾化吸入诱导肠道菌群失调小鼠肺部过敏反应的发生

目的:在抗生素所致肠道菌群失调小鼠模型上采用卵清蛋白(OVA)雾化吸入激发,探讨气道变应性反应与肠道菌群失调的关系.方法:112只BALB/c小鼠分为6组:菌群失调Ⅰ组、对照Ⅰ组、菌群失调Ⅱ组、菌群失调加激发组、激发组、对照Ⅱ组.前2组和后4组分别于第6天和第14天时取盲肠内容物做细菌培养计数,后4组同时行支气管肺泡灌洗液(BALF)细胞分类计数、BALF和血清中OVA特异性IgE(OVA-sIgE)检测以及肺部病理观察;采用流式细胞术检测肺组织中Th1以及Th2细胞水平.结果:应用抗生素的小鼠出现肠道菌群失调,菌群失调加激发组小鼠肺部出现以嗜酸粒细胞和淋巴细胞为主的炎症细胞浸润,肺部黏液分泌明显增高,BALF中细胞总数、淋巴细胞、嗜酸粒细胞和中性粒细胞增加,OVA-sIgE水平显著增高,肺部Th2细胞水平增高,Th1细胞与对照组无差异.结论:抗生素致肠道菌群失调小鼠经过OVA雾化吸入后,可产生Th2细胞优势的变应性气道反应,提示抗生素所致肠道菌群失调是诱发哮喘等变应性疾病的危险因素之一.     

Synthesized OVA323-339MAP octamers mitigate OVA-induced airway inflammation by regulating Foxp3 T regulatory cells

ABSTRACT: BACKGROUND: Antigen-specific immunotherapy (SIT) has been widely practiced in treating allergic diseases such as asthma. However, this therapy may induce a series of allergic adverse events during treatment. Peptide immunotherapy (PIT) was explored to overcome these disadvantages. We confirmed that multiple antigen peptides (MAPs) do not cause autoimmune responses, which led to the presumption that MAPs intervention could alleviate allergic airway inflammation without inducing adverse effects. RESULTS: In this study, synthesized OVA323-339MAP octamers were subcutaneously injected into ovalbumin (OVA)-sensitized and -challenged Balb/c mice to observe its effect on allergic airway inflammation, Th2 immune response, and immune regulating function. It was confirmed that OVA sensitization and challenge led to significant peritracheal inflammatory, cell infiltration, and intensive Th2 response. Treatment of OVA323-339MAP octomers in the airway inflammation mice model increased CD4+CD25+Foxp3+ T regulatory (Treg) cells and their regulatory function in peripheral blood, mediastinal draining lymph nodes, and the spleen. Furthermore, OVA323-339MAP increased IL-10 levels in bronchial alveolar lavage fluid (BALF); up-regulated the expression of IL-10,membrane-bound TGF-beta1, as well as Foxp3 in lung tissues; and up-regulated programmed death-1 (PD-1) and cytotoxic T lymphocyte associated antigen 4 (CTLA-4) on the surface of Treg cells. These results were further correlated with the decreased OVA specific immunoglobulin E (sIgE) level and the infiltration of inflammatory cells such as eosinophils and lymphocytes in BALF. However, OVA323-339 peptide monomers did not show any of the mentioned effects in the same animal model. CONCLUSIONS: Our study indicates that OVA323-339MAP had significant therapeutic effects on mice allergic airway inflammation by regulating the balance of Th1/Th2 response through Treg cells in vivo. Key words Allergic airway inflammation; Specific immunotherapy; Multiple antigen peptide.     

Characteristic features of allergic airway inflammation in a murine model of infantile asthma

BACKGROUND: The pathophysiology of infantile asthma may differ from that in older children or in adults, partly because of the different immune response depending upon maturation. In adult mice, the sensitizing dose of antigen is known to be critical to the polarized development of helper T cell subsets and allergic airway inflammation. We wanted to know the characteristics of allergic airway inflammation of infantile asthma by developing a murine model. METHODS: BALB/C mice at different stages of maturation (juvenile: 3 days after birth; adult: 8 weeks of age) were sensitized with 10 or 1,000 microg ovalbumin (OVA) or vehicle. The animals were then challenged with aerosolized OVA or saline once a day during 6 consecutive days. After the final challenge, bronchial hyperresponsiveness (BHR), bronchoalveolar lavage fluid (BALF), histological changes in the airways and immunological status were examined. RESULTS: In both juvenile and adult animals, sensitization with 10 microg OVA induced the T helper 2 response (elevated IL-4 and decreased IFN-gamma levels). BHR, airway eosinophilia, the inflammatory cell infiltration, goblet cell metaplasia (GCM), and IgE antibody production were more prominent in animals given this dose than 1,000 microg OVA. Among these responses, GCM as well as BALF IL-4, and BHR were comparable between juvenile and adult animals, whereas other parameters were lower in juvenile animals, especially in those given 1,000 microg OVA. CONCLUSION: GCM and, consequently, airway mucus hypersecretion may be an important component of allergic airway inflammation in infantile asthma.