Treg抑制DC活性调控小鼠肺部炎症发生发展

目的 探讨调节性T细胞(Treg)在变态反应性肺泡炎中的作用及Treg对变态反应性肺泡炎发生发展过程中树突状细胞(DC)活性影响。方法 腹腔注射抗CD25单克隆抗体建立小鼠Treg消除模型,通过气管灌注1-3-β葡聚糖建立小鼠变态反应性肺泡炎模型,采用流式细胞术检测小鼠肺门淋巴结中树突状细胞活性;苏木素-伊红染色进行病理观察,比较各组小鼠肺组织切片中炎症反应和肉芽肿程度。结果 与葡聚糖模型组小鼠比较,Treg消除小鼠肺门淋巴结中CD4+CD25+Treg百分比[(6.76±1.0)%]明显降低(P < 0.05);组织病理观察显示,Treg消除小鼠肺组织局部炎症反应程度明显重于葡聚糖模型组小鼠;流式细胞术检测发现,葡聚糖灌注后早期,小鼠肺门淋巴结中CD80+MHCII+DC的比例较对照组明显增加;Treg消除小鼠肺门淋巴结和脾细胞中CD80+MHCII+DC比例[(37.3±5.8)%]较葡聚糖模型组小鼠[(24.3±1.9)%]显著升高,差异具有统计学意义(P < 0.05)。结论 Treg参与抑制变态反应性肺泡炎的发生发展,其机制可能与抑制DC活性发挥免疫抑制作用有关。

Regulation of Treg on development of pulmonary inflammation via suppressing activation of dendritic cells in mice

Objective To investigate the role of regulatory T cell(Treg) in allergic alveolitis and the effect of Treg on the activation of dendritic cells (DC) during the development of allergic alveolitis.Methods Intraperitoneal injection of anti-CD25mAb was used to develop Treg depletion model and introtrachea administration of 1-3-β-glucan was used to set up allergic alveolitis model in mice.The activation of DC in hiliar lymph node and spleen was checked with flow cytometry.Hematoxylin and eosin staining was used to compare the inflammation and granuloma among different groups.Results Compared with the glucan group,the Treg's percentage in hiliar lymph node in glucan+anti-CD25 group(6.76±0.91%) reduced obviously(P < 0.05).Histological observation showed that the lung inflammation degree in glucan+anti-CD25 mice was significantly higher than that of glucan group.According to the examination of flow cytometry,the percentage of CD80+MHCII+DC in glucan group was increased in the early stage after glucan administration.Meanwhile,the percentage of CD80+MHCII+DC in glucan+anti-CD25 group in both hiliar lymph node and spleen(37.3±5.8%) was increased compared with that in glucan group (24.3±1.9%).Conclusion Treg participates in regulating the development of allergic alveolitis through suppressing the activation of DC.