弓形虫排泄-分泌抗原含糖组分对小鼠调节性T细胞的影响

目的观察弓形虫排泄-分泌抗原(ESA)含糖组分对小鼠CD4+CD25+Foxp3+Treg细胞的影响。方法采用刀豆蛋白A(ConA)琼脂糖凝胶亲和层析技术提取ESA中的含糖组分,经硫酸-苯酚法测定提取物糖含量,并采用BCA法进行蛋白定量测定。将20只雌性C57BL/6小鼠随机分为5组,分别对各组小鼠腹腔注射ESA、ConA结合ESA、ConA未结合ESA、完全RPMI-1640和甘露糖各100μl。4d后处死,流式细胞仪检测各组脾脏CD4+CD25+Foxp3+Treg细胞占脾细胞的比例。结果采用ConA琼脂糖凝胶亲和层析法成功提取弓形虫ESA中含糖成分。与对照组相比(RPMI-1640组和甘露糖组),ESA、ConA结合ESA、ConA未结合ESA注射组小鼠的CD4+CD25+Foxp3+Treg细胞占脾细胞的比例均明显下降(P均0.01)。结论弓形虫ESA中含糖组分和蛋白组分均能引起小鼠CD4+CD25+Foxp3+Treg细胞占脾细胞的比例下降。

Changes of CD4+CD25+ Foxp3+ Treg cells induced by glycans isolated from Toxoplasma gondii excreted-secreted antigens

Objective To determine the effects of glycan components from Toxoplasma gondii excreted-secreted antigens（ESA）on CD4^＋CD25^＋Foxp3^＋ Treg cells.Methods Glycan components and protein components were isolated from T.gondii excreted-secreted antigens （ESA） by ConA affinity chromatography,and injected intraperitoneally into C57BL/6 mice,respectively.The percentages of splenic CD4^＋CD25^＋Foxp3^＋ Treg cells were detected by flow cytometry.Results Four days post-injection,the percentages of splenic CD4＋CD25＋Foxp3＋ Treg cells in all splenic cells decreased significantly in both glycan components-treated and protein components-treated mice comparing with that in the control mice （P〈0.01）,which were similar to that of T.gondii ESA injection.Conclusion Both the glycan components and the protein components of T.gondii ESA have roles on the reduction of murine CD4^＋CD25^＋Foxp3^＋ Treg cells.