CD_4^+CD_(25)^+调节性T细胞在糖尿病发病中作用的研究

Role of CD_4^+CD_(25)^+ Regulatory T Cells in Diabetes Mellitus

目的:探讨CD4+CD25+调节性T细胞在糖尿病发病中的作用及机制。方法:选取BALB/c小鼠,每日腹腔注射链脲佐菌素(STZ)40mg/kg,连续5天,建立1型糖尿病模型;从小鼠内眦静脉采血,检测血糖;取小鼠尿液,检测尿糖;流式细胞术检测两种小鼠感染不同时间脾细胞悬液中CD4+T细胞和CD4+CD25+T细胞百分含量;ELISA法检测脾细胞培养上清IFN-γ和IL-10水平。结果:BALB/c小鼠的IFN-γ水平在注射STZ第2周和4周明显增高(P<0.05);IL-10水平在注射STZ第2周和4周明显降低(P<0.05);CD4+T细胞数量在注射STZ第2周未见明显升高,第4周水平明显升高(P<0.05);CD4+CD25+T细胞数量在注射STZ第2周和4周明显降低(P<0.05)。结论:CD4+CD25+调节性T细胞通过抑制Th1型细胞因子分泌,分泌IL-10等细胞因子,防止糖尿病的发生,维持自身耐受。

Objective：To investigate the influences of CD4＋CD25＋regulatory T cells on cellular activation in diabetes mellitus.Methods：BALB/c mice were infected by i.p.injection of STZ.Blood glucose of individual mice was monitored by the Blood glucose meter.Mice from normal and experimental groups were sacrificed on 0d,2w and 4w after injection for collection of spleen cells.Applying Flow Cytometry to quantitatively analyze CD4＋ T cells and CD4＋CD25＋T cells,levels of IFN-γ and IL-10 in spleen supernatants were measured by ELISA kits.Result：The levels of IFN-γincreased rapidly at 2w and 4w（P〈0.05）,the levels of IL-10 decreased rapidly at 2w and 4w（P〈0.05）,the number of CD4＋ T cells remained unchanged at 2w,and increased rapidly at 4w（P〈0.05）,the proportion of CD4＋CD25＋T lymphocytes decreased obviously at 2w and 4w（P〈0.05）.Conclusion：CD4＋CD25＋ regulatory T cells perhaps suppress the secretion of Th1 cytokine,promote IL-10 secretion,prevent the occurrence of diabetes mellitus and maintain immune tolerance.