调节性T细胞通过膜结合转化生长因子β1影响效应性T细胞凋亡  

The effect of regulatory T cells on apoptosis of effector T cells via membrane-bound transforming growth factor-β1

作　　者：尹承芬[1] 秦庆华[2] 董宁[2] 祝筱梅[2] 张庆红[2] 姚咏明[2] 

机构地区：[1]温州医学院附属第一医院急诊中心,温州325000 [2]解放军总医院第一附属医院全军烧伤研究所

出　　处：《中国急救复苏与灾害医学杂志》2013年第3期215-219,共5页China Journal of Emergency Resuscitation and Disaster Medicine

基　　金：国家自然科学基金项目（81071545,30971192,81130035,81121004）;国家重点基础研究发展计划项I~（2012CB518102）;全军“十二五”计划重大项目（AWS11J008）

摘　　要：目的观察CD4＋CD25＋T细胞（效应性T细胞，Teff）凋亡情况，进-步探讨调节性T细胞（Treg）对Teff凋亡的影响及其作用机制。方法免疫磁珠法分选Balb／c小鼠脾脏的Tregs与Teff，流式细胞仪检测Tregs与抗CD3／CD28抗体刺激的Treg膜表面转化生长因子（TGF）-β1的表达、PCR技术检测其基因表达水平。将Treg与Teff共培养，然后采用抗TGF—β抗体拮抗，观察Tefr的凋亡率、线粒体膜电位变化以及胞内Smad2、磷酸化Smad2（P—Smad2）、Bim、Bcl-2蛋白表达水平。结果抗CD3／CD28抗体刺激后TregTGF—β1＋及其基因表达均明显上调（P均〈0．01）；与Treg共培养的Teff凋亡率升高（P〈0．01）、线粒体膜电位降低（P〈0．01）；胞内P—Smad2（P〈0．01）、Bim（P〈0．05）蛋白表达量增加、Bcl-2蛋白表达量降低（P〈0．01）。加入抗TGF—β1抗体后Teff凋亡率显著降低（P〈0．01）、线粒体膜电位升高（P〈0．01）、胞内P-Smad2（P〈0．01）、Bim（P〈0．05）蛋白表达水平降低、Bcl-2蛋白表达量则升高（P〈0．01），Smad2蛋白表达水平在三组之间均未见明显差异（P〉0．05）。结论调节性T细胞可通过膜结合型TGF-β1促进效应性T细胞的凋亡。Objective To investigate the change in apoptotic rate of CD4＋CD25-T ceils （Te10, and explore the effect and potential mechanism of regulatory T cell （Treg） on apoptosis rate of Teffs. Methods Tregs and Teffs were isolated from the spleens of male Balb/e mice by the magnetic beads. TGF-β1 mRNA expression as well as TGF-β1m＋ protein level of Tregs, and Tregs stimulated with anti-CD3/CD28 antibody were examined by PCR and flow cytometry, respectively. Tregs and Teffs were cocultured and then were treated with anti-TGF-βantibody. The apoptotic rate, mitochondrial membrane potential and protein expression of Smad2, P-Smad2, Bim and Bcl-2 of Tells were determined by corresponding techniques. Results TGF-β1m＋ protein levels and TGF-β1 mRNA expression of Tregs stimulated with anti-CD3/CD28 antibody were significantly up-regulated （P〈0.01）. The apoptotic rate of Teffs treated with Tregs was markedly increased （P〈0.01）, and mitochondrial membrane potential was significantly reduced （P〈0.01）; the protein expressions of P-Smad2, Bim in Teffs were significantly elevated （P〈0.05）, while Bcl-2 level was significantly decreased （P〈0.01）. After treatment with anti-TGF-β antibody, the apoptotic rate （P〈0.01）, protein expressions of P-Smad2 （P〈0.01） as well as Bim （P〈0.05） were down-regulated sharply, while mitochondrial membrane potential and the protein expression of Bcl-2 were significantly enhanced （P〈0.01）. However, Smad2 protein expression showed no significant difference among three groups. Conclusion These data indicated that regulatory T cells might have the ability to promote apoptosis of effector T cells via membrane-bound TGF-β1.

关 键 词：调节性T细胞 转化生长因子 效应性T细胞 凋亡 线粒体膜电位 

分 类 号：R392.12[医药卫生—免疫学]