地塞米松对哮喘大鼠气道炎症及CD4+ CD25+ 调节性T细胞的影响

目的 观察地塞米松对支气管哮喘(哮喘)大鼠气道炎症和CD4+ CD25+调节性T细胞(CD4+ CD25+ Tr)的影响,探讨地塞米松治疗哮喘的机制.方法 30只Wistar大鼠随机分成正常对照组,哮喘组,地塞米松组.计数支气管肺泡灌洗液(BALF)中细胞总数并分类,应用HE染色行肺组织病理学检查,流式细胞仪检测外周血单个核细胞(PBMCs)中CD4+ CD25+ Tr的比例.结果 地塞米松组BALF细胞总数及淋巴细胞(Lym)、中性粒细胞(Neu)和嗜酸性粒细胞(Eos)百分率较哮喘组明显减少(P＜0.05,P＜0.01),与正常对照组比较差异无统计学意义(P＞0.05).病理组织学显示:地塞米松组较哮喘组肺组织炎性细胞浸润明显减少.哮喘组PBMCs中CD4+ CD25+ Tr比例较正常对照组明显减少(P＜0.05),地塞米松组CD4+ CD25+ Tr比例较哮喘组明显增加(P＜0.05).结论 地塞米松可减轻哮喘大鼠气道炎症反应,其机制可能与促进CD4+ CD25+ Tr产生有关.

Influence of dexamethasone on airway inflammation and CD4+ CD25+ regulatory T cells of asthmatic rats

Objective To investigate dexamethasone on airway inflammation and CD4+ CD25 + regulatory T cells (CD4+ CD25 +Tr) of asthmatic rats,and elucidate the possible mechanism of dexamethasone in treatment of asthma.Methods 30 Wistar rats were randomly divided into control group,asthma group and dexamethasone-treated group.Bronchoalveolar lavage fluid (BALF) was collected,and cytology study was conducted.The lung tissue was obtained and pathologic analysis was done through HE stain.Flow eytometry was used to detect the CD4+ CD25 +Tr ratio in PBMCs.Results Total cells number,the percentage of lymphocytes,neutrophils and eosinophils (Eos)in BALF of dexamethasone-treated group were lower than that of asthma group (P＜0.05,P＜0.01).Compared with the asthma group,less infiltration of inflammatory cells in lung tissues was observed in the dexamethasone-treated group.CD4+ CD25 + Tr of asthma group was lower than that of control and dexamethasone-treated group (P＜0.05).Conclusion Dexamethasone could suppress airway inflammation of asthmatic rats,which probably be due to increasing the number of CD4+ CD25 + Tr.