| 摘要: |
| 目的 观察肺炎链球菌3型多糖(T3P)对支气管哮喘小鼠气道炎症以及Treg/Th17细胞的影响,探讨T3P对哮喘小鼠的免疫调节作用。方法 BALB/c小鼠随机分成对照组、哮喘组和T3P组,每组8只。哮喘组以卵清蛋白(OVA)致敏、气道激发建立哮喘模型,对照组以PBS代替,T3P组在OVA致敏前皮下注射T3P进行干预。观察小鼠肺组织病理改变,对支气管肺泡灌洗液(BALF)进行细胞计数及分类,ELISA法检测血清OVA特异性IgE(OVA-IgE)以及BALF中白介素4(IL-4)、干扰素γ(IFN-γ)、IL-10、IL-17浓度,实时荧光定量PCR法检测肺组织中转录因子Foxp3和RORγt mRNA表达水平,流式细胞术检测Treg和Th17细胞占CD4+细胞百分比。结果 T3P组小鼠肺组织炎症反应程度弱于哮喘组，血清OVA-IgE，BALF中细胞总数、嗜酸粒细胞比例以及IL-4、IL-17浓度均低于哮喘组(P<0.05),IFN-γ、IL-10浓度高于哮喘组(P<0.05),小鼠肺组织Foxp3 mRNA表达水平及Treg占CD4+细胞百分比均高于哮喘组(P<0.05), RORγt mRNA表达水平和Th17细胞占CD4+细胞百分比均低于哮喘组(P<0.05)。哮喘组和T3P组小鼠肺组织Foxp3-mRNA/RORγt-mRNA比值及Treg/Th17细胞比例与BALF中嗜酸粒细胞数量呈负相关。结论 T3P可以通过抑制过敏原特异性IgE表达调节Th1/Th2、Treg/Th17细胞平衡,抑制气道炎症。 |
| 关键词: 3型多糖 哮喘 调节性T淋巴细胞 Th17细胞 炎症 |
| DOI：10.3724/SP.J.1008.2013.00471 |
| 投稿时间：2013-01-14修订日期：2013-04-09 |
| 基金项目: |
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| Effects of type-3-polysaccharide on airway inflammation and Treg/Th17 cells in bronchial asthmatic mice |
| ZHOU Li-rong,ZHANG Jie,LUO Yong-ai* |
(Department of Respiratory Medicine, The First Affiliated Hospital of Chongqing Medical University, Chongqing 400016, China
*Corresponding author.) |
| Abstract: |
| Objective To investigate the effects of type-3-polysaccharide (T3P) on airway inflammation and Treg/Th17 cells in bronchial asthmatic mice, so as to explore the immunoregulation mechanism of T3P in asthmatic mice. Methods BALB/c mice were randomly divided into 3 groups, with 8 mice in each group. The control group received PBS treatment, the asthma group were sensitized and challenged with ovalbumin(OVA),and the T3P group received a pretreatment with T3P by subcutaneous injection before sensitization with OVA. The pulmonary histological changes were observed and differential cell counts in bronchoalveolar lavage fluid(BALF) were performed. Serum OVA-IgE and IFN-γ, IL-4, IL-17 and IL-10 levels in the BALF were detected by enzyme-linked immunosorbent assay (ELISA). The levels of Foxp3 and RORγt mRNA expression were measured by real-time fluorescence-based quantitative PCR. The proportions of Treg and Th17 cells in CD4+ cells were assessed by flow cytometric analysis. Results The inflammatory degree of pulmonary tissue, serum OVA-IgE, and total cell number, proportion of eosinophils, and IL-4, IL-17 levels in BALF were significantly lower in T3P group than in the asthma group (P<0.05). The BALF levels of IFN-γ and IL-10, Foxp3 mRNA expression and proportion of Treg cells among CD4+ cells were significantly higher in the T3P group than in the asthma group (P<0.05), while RORγt mRNA expression and the proportion of Th17 cells among CD4+ cells were significantly lower than in the asthma group (P<0.05). The count of BALF eosinophils was negatively correlated with the ratios of Foxp3-mRNA/RORγt-mRNA and Treg/Th17 in asthma and T3P groups (P<0.05). Conclusion T3P may inhibit airway inflammation by inhibiting OVA-IgE and regulating Th1/Th2 and Treg/Th17 cell balance in asthmatic mouse model． |
| Key words: type-3-polysaccharide asthma regulatory T-lymphocytes Th17 cells inflammation |
