目的研究抑制树突状细胞(DCs)自噬对DCs功能及小鼠哮喘的影响。方法 (1)将BALB/c小鼠按随机数字表法分为3组:急性哮喘对照组(哮喘组)、哮喘自噬抑制剂氯喹(CQ)治疗组(CQ组)和空白对照组(对照组)。哮喘组和CQ组利用卵清蛋白(OVA)诱导建立小鼠过敏性哮喘模型,CQ组加用CQ。用H-E染色观察各组小鼠肺组织的病理改变,酶联免疫吸附实验、蛋白质印迹实验、流式细胞术分别检测各组小鼠血清OVA特异性IgE以及肺DCs自噬水平、表面共刺激分子和主要组织相容性复合体Ⅱ类分子(MHCⅡ)的表达水平。(2)体外用自噬抑制剂3-甲基腺嘌呤(3MA)抑制C57/B6小鼠骨髓源DCs自噬,检测DCs表面共刺激分子、MHCⅡ的表达水平。(3)获取OT2小鼠脾脏CD4+T淋巴细胞,与各组肺DCs以1∶10的比例混匀,流式细胞术检测T细胞的增殖情况与活化反应。结果 (1)CQ组IgE的表达水平(P〈0.05)、肺炎症细胞浸润程度以及肺DCs自噬水平(P〈0.05)和CD86、MHCⅡ表达水平(P〈0.05)均低于哮喘组。(2)3MA体外抑制骨髓源DCs自噬后,DCs表面的CD86及MHCⅡ表达均低于哮喘组(P〈0.05)。(3)CQ组肺DCs体外诱导的T细胞增殖能力与活化反应均弱于哮喘组(P〈0.05)。结论自噬抑制剂可抑制过敏性哮喘肺DCs的自噬,下调DCs表面共刺激分子、MHCⅡ的表达以及DCs诱导的T细胞增殖能力,改善哮喘病情。
Objective To study the impact of autophagy inhibition on functions of dendritic cells (DCs) and mouse model of allergic asthma. Methods (1)BALB/c mice were divided into three groups using the random number table: asthma model group, asthma treated with autophagy inhibitor (chloroquine) group (asthma+CQ group) and control group. Mouse models in asthma group and asthma+CQ group were induced with ovalbumin (OVA) ; meanwhile, mice of asthma+CQ group were also treated with autophagy inhibitor CQ. Hematoxylin-Eosin (H-E) staining was used to observe the pathological changes in lung tissues of mice. ELISA, Western blotting analysis and flow cytometery were used to detect the serum OVA-specific IgE, autophagy level, and expression of surface co-stimulatory molecules and major histocompatibility complex class Ⅱ (MHC Ⅱ ) on lung DCs, respectively. (2)Bone marrow-derived DCs were treated with autophagy inhibitor 3-methyladenine (3MA) in vitro and the surface expression of co-stimulatory molecules and MHC Ⅱ was detected. (3) We sorted CD4+ T cells from spleens of OT2 mice, then co-cultured with lung DCs from mice of different groups (T cells : DCs= 1 : 10), and detected the activation and proliferation of T cells with flow cytometery. Results (1) The level of OVA-specific IgE (P ~ 0. 05 ), extent of inflammatory cell infiltration in lung tissues, autophagy level in lung DCs (P〈0. 05), and expression of CD86 and MHC Ⅱ (P〈0.05)on lung DCs in asthma +CQ group were significantly lower than those in the asthma group. (2) 3-MA treatment decreased the surface expression of CD86 and MHC Ⅱ on bone marrow derived DCs (P〈0. 05). And (3) lung DCs from asthma+CQ group had lower ability for activating T cells and promoting T cell proliferation than those from the asthma group (P〈 0.05 ). Conclusion Autophagy inhibitors can improve the pathologic condition of allergic asthma through inhibiting autophagy in DCs, down-regulating su