口服重组β2糖蛋白1的实验性抗磷脂综合征小鼠CD4^+CD25^+调节性T细胞及Foxp3 mRNA表达变化

Changes of CD4^+CD25^+ regulatory T cells and Foxp3 mRNA expression in mice with experimental anti-phospholipid syndrome fed with recombinant human β2-glycoprotein 1

目的:观察口服重组人β2糖蛋白1(rhβ2GP1)的实验性抗磷脂综合征(EAPS)小鼠CD4+CD25+调节性T细胞(CD4+CD25+Treg)数量和功能变化,探讨EAPS口服耐受机制。方法:以rhβ2GP1主动免疫BALB/c小鼠建立EAPS模型,口服耐受组在EAPS小鼠免疫10天前经胃肠道给予rhβ2GP1,在免疫12周后检测各组小鼠抗β2糖蛋白1抗体(anti-β2-GP1)、抗心磷脂抗体(aCL)、流产率(%)、活化部分凝血活酶时间(aPTT)、血小板计数(PLTPBC);以流式细胞术检测各组小鼠PBMC中CD4+CD25+Treg细胞百分率;RT-PCR检测转录因子Foxp3mRNA的表达。结果:耐受组小鼠与模型组相比,anti-β2-GP1、aCL水平明显降低,aPTT缩短,PLTPBC升高,流产率降低,均具有显著性差异(P<0.05);耐受组小鼠PBMC中Foxp3mRNA表达在第4、8、12周均高于对照组(P<0.05),此后下降,20周时与正常对照组无明显差异(P>0.05),4周时与模型组无差异(P>0.05),8周后模型组逐渐降低,12周后降低明显(P<0.05);耐受组PBMC中CD4+CD25+Treg细胞百分率与对照组相比,未见显著性差异(P>0.05)。结论:CD4+CD25+Treg在口服耐受的诱导中发挥作用。

Objective：To observe the quantitative and functional changes of CD4＋CD25＋ regulatory T cells（CD4＋CD25＋Treg）in experimental anti-phospholipid syndrome（EAPS）mice fed with recombinant human β2-glycoprotein 1（rhβ2-GP1）.Methods：EAPS model was established by immunizing BALB/c mice with rhβ2-GP1.In tolerized groups,EAPS mice were fed with rhβ2-GP1 10 days before immunization.Anti-β2-glycoprotein 1（anti-β2GPI）,anticardiolipin（aCL）titers in the sera,rate of the fetal resorptions,activated partial thromboplastin time（aPTT）and platelet counts were assayed after 12 weeks.Percentage of CD4＋CD25＋Treg in peripheral blood mononuclear cells in mice from each groups were determined by flow cytometry,the expressions levels of Foxp3 mRNA were detected by RT-PCR.Results：In tolerized mice anti-β2GPI and aCL Abs decreased significantly（P0.05）,resorption percentage decreased（P0.05）,aPTT shortened（P0.05）,and platelet counts elevated（P0.05）.The expressing levels of Foxp3 mRNA in the tolerized group were higher than those of control group（P0.05）on the fourth,eighth,twelfth weeks after immunization（P0.05）,but they began to decrease after twelfth week and there were no significant differences on twentieth weeks between tolerized groups and control group（P0.05）.The expressing levels of Foxp3 mRNA in the tolerized group were paralleled to model group on fouth week（P0.05）and the latter began to decrease after eighth week and were lower than those of control group significantly after twelfth week（P0.05）.The percentage of CD4＋CD25＋Treg cells from PBMC in tolerized group were paralleled to those of control group during oral tolerance induction（P0.05）.Conclusion：CD4＋CD25＋Treg cells play roles in the induction of oral tolerance in EAPS.