目的观察1',2',3',7'-四氢茶黄素-3,3'-双没食子酸酯(TF3-H4)对CD4+CD25+调节性T细胞和CD4+CD25-效应性T细胞早期活化的影响,分析TF3-H4对两群功能相反的CD4+T细胞的作用。方法免疫磁珠分离BALB/c小鼠脾脏CD4+CD25+调节性T细胞和CD4+CD25-效应性T细胞,加入ConA或PDB,和TF3-H4共同孵育12 h后收集细胞,流式细胞仪分析细胞表面早期活化标志CD69的表达。结果在ConA和PDB的作用下,两群细胞早期活化标志CD69的表达均升高。TF3-H4(20 mg.L-1)不能抑制PKC激动剂PDB激活的CD4+CD25-效应性T细胞CD69的表达,却能抑制ConA激活的CD4+CD25-效应性T细胞CD69表达;同时,TF3-H4也能明显抑制ConA激活的CD4+CD25+调节性T细胞的CD69表达。结论茶黄素衍生物TF3-H4可能经由TCR活化途径的上游抑制CD4+CD25-效应性T细胞活化;TF3-H4对CD4+CD25+调节性T细胞和CD4+CD25-效应性T细胞早期活化的抑制作用,可能是该类化合物发挥抗炎、抗肿瘤作用的机制之一。
Aim To study the effects of theaflavin derivative compound,1′,2′,3′,7′-4H-Theaflavin-3,3′-digallate(TF3-H4),on the early activation of CD4+CD25+ regulatory T cells and CD4+CD25-effector T cells,and evaluate the effects of TF3-H4 on two groups of CD4+T cells with opposite functions.Methods The CD4+CD25+ regulatory T cells and CD4+CD25-effector T cells of BALB/c mice were separated by MACS immunomagnetic beads.After 12 hours of stimulation with ConA or PDB with or without the presence of TF3-H4,the cells were collected and the percentage of CD69 expression was analyzed by flow cytometry.Results Both ConA and PDB could increase CD69 expression of CD4+CD25+ regulatory T cells and CD4+CD25-effector T cells.TF3-H4 at 20 mg·L-1 could decrease CD69 expression of CD4+CD25-effector T cells stimulated by ConA,but had no effect on CD69 expression of CD4+CD25-effector T cells stimulated by PDB.Moreover,CD69 expression of CD4+CD25+ regulatory T cells stimulated by ConA was also suppressed significantly by TF3-H4.Conclusions The activation of CD4+CD25-effector T cells in vitro might be inhibited by TF3-H4 through the upstream pathway of TCR.The inhibitory function of TF3-H4 on the early activation of CD4+CD25+ regulatory T cells and CD4+CD25-effector T cells may contribute to its anti-inflammation and anti-tumor effects.