中文摘要：

目的探讨地塞米松对哮喘小鼠CD4^＋、CD25^＋调节性T细胞（regulatory T cells,Treg）及IL-4、TGF-β水平的影响。方法 30只雄性BALB/c小鼠随机分为正常对照组、哮喘组及地塞米松组3组各10只;利用鸡卵白蛋白腹腔注射、雾化吸入制备哮喘模型;使用流式细胞仪分别检测各组小鼠脾脏单个核细胞CD4^＋、CD25^＋Treg细胞占CD4^＋T细胞的百分比;使用Western Blot方法分析IL-4在小鼠肺组织中的表达情况;使用酶联免疫吸附试验方法检测各组小鼠血清中TGF-β的水平。结果哮喘组小鼠脾单个核细胞CD4^＋、CD25^＋Treg细胞百分比及TGF-β水平较正常对照组降低（均P〈0.05）,哮喘组IL-4水平较正常对照组增高（P〈0.05）,地塞米松组与正常对照组比较,差异无统计学意义（P〉0.05）。结论哮喘小鼠CD4^＋、CD25^＋Treg数量的减少,功能的下降,可能参与了哮喘的发病过程,地塞米松可能通过上调CD4^＋、CD25^＋Treg比例,调节T细胞亚群失衡来发挥抗炎作用。

英文摘要：

Objective To discuss the effect of dexamethasone on CD4^＋CD25^＋regulatory T cells（Treg）and the expression of IL-4and TGF-βin asthmatic mice.Methods Thirty male BALB/c mice were randomly assigned to the control group,the asthma group and the dexamethasone group.Tissues of left lung were obtained from mice to observe pathological changes.Flow cytometry was used to detect the percentage of CD4^＋CD25^＋Treg in CD4^＋T cells.The expression of IL-4from lungs were detected by Western Blot.The levels of serum TGF-βwere detected by ELISA.Results The percentage of CD4^＋CD25^＋Treg and TGF-βin asthma group decreased significantly（P〈0.05）.The expression of IL-4in asthma group increased significantly（P〈0.05）.Difference was not significant be-tween the control group and the dexamethasone group（P〉0.05）.Conclusion The number of CD4^＋CD25^＋Treg in asthmatic mice reduced and the function also declined.They are involved in the pathogenesis of asthma.Dexamethasone may had anti-inflammatory effect through the up regulation of CD4^＋CD25^＋Treg and regulatory T cell subsets imbalance.