T-bet和GATA-3在实验性自身免疫性重症肌无力中的表达

Expression of T-bet and GATA-3 in the EAMG

目的通过研究表达在T细胞上的T-box家族成员之一(T-bet)和能与[T/A(GATA)A/G]序列结合的锌指结构家族的转录因子之一(GATA-3)这两种转录因子在实验性自身免疫性重症肌无力(EAMG)中的表达,探讨其在EAMG发病机制中的作用。方法密度梯度离心法分离EAMG组和对照组大鼠外周血单个核细胞(PBMCs)后,采用酶联免疫吸附测定法(ELISA)检测二组大鼠血清干扰素-γ(IFN-γ)和白介素-4(IL-4)含量;逆转录-聚合酶链反应(RT-PCR)检测PBMCs中T-bet和GATA-3的表达。结果对照组和EAMG组PBMCs中,T-bet的表达量分别为0.65±0.15和0.86±0.13,两组比较差异具有显著性(P<0.01);GATA-3的表达量分别为0.46±0.12和0.67±0.11,差异也具有显著性(P<0.01);血清中IFN-γ的含量,对照组(108.22±19.01)pg/ml明显低于EAMG组(230.86±41.44)pg/ml(P<0.01);对照组IL-4含量(87.33±3.50)pg/ml明显低于EAMG组(96.21±4.77)pg/ml(P<0.01);T-bet表达与IFN-γ及GATA-3表达与IL-4在对照组和EAMG组分别呈显著正相关(r=0.89,r=0.89,P<0.01;r=0.92,r=0.88,P<0.01)。结论T-bet和GATA-3在EAMG大鼠PBMCs中表达均显著增高,这可能是EAMG大鼠细胞和体液免疫反应增强的重要原因之一。

Objective To investigate the expression of transcription factor T-bet and GATA-3 in peripheral blood mononuclear cells（PBMCs）of experimental autoimmune myasthenia gravis（EAMG）and their functions in pathogenesis of EAMG.Methods PBMCs were isolated by density gradient centrifugation from rats of EAMG and control group.Expression of T-bet and GATA-3 mRNA was detected by RT-PCR.The concentrations of IFN-γ and IL-4 in the serum were determined by ELISA.Results The expression of T-bet mRNA were（0.65±0.15）in the control group and（0.86±0.13）in the EAMG group,and there was a significant difference between the two groups（P〈0.01）.The levels of GATA-3 mRNA expression were（0.46±0.12）in the control group and（0.67±0.11）in the EAMG group,there was also a significant difference between the two groups（P〈0.01）.In the control group,the concentration of IFN-γ in the serum was（108.22±19.01）pg/ml,which was significantly lower compared with that in the EAMG group（230.86±41.44）pg/ml（P〈0.01）,in the control group,and the concentration of IL-4 in the serum was（87.33±3.50）pg/ml,which was significantly also lower than that of the EAMG group（96.21±4.77）pg/ml（P〈0.01）.IFN-γ and IL-4 were positively correlated with T-bet and GATA-3 mRNA in both groups,respectively.（r=0.89,r=0.89,P〈0.01;r=0.92,r=0.88,P〈0.01）.Conclusion EAMG is associated with the up-regulation of T-bet and GATA-3 expression,which might be responsible for the enhancement of immunologic response in EAMG.