外周血自然调节性T细胞和主动脉TNF-α在动脉粥样硬化发展中的表达

Peripheral Blood Natural Regulatory T Cells and the Expression of TNF-α in Aortas during the Progression of Atherosclerosis

目的探讨外周血自然调节性T细胞(natural regulatory T cell,nTreg)和主动脉肿瘤坏死因子(tumor necrosis factor,TNF)α表达在动脉粥样硬化(atherosclerosis,AS)发展中的免疫调节作用。方法雄性SD大鼠36只,体重100g±10g,随机分3组,每组12只。健康对照组(A组)、早期动脉粥样硬化组(B1组)、晚期动脉粥样硬化组(B2组)。采用高脂高糖饮食配合腹腔注射维生素D_3针剂建立大鼠AS模型。流式细胞仪检测各组大鼠外周血CD4^+CD25^+Foxp3^+调节性T细胞比例,免疫组化检测大鼠主动脉根部TNF-α表达。结果 A组大鼠主动脉根部未见斑块形成,B1组大鼠主动脉根部可见纤维斑块形成,B2组大鼠主动脉根部可见粥样斑块形成。B1、B2组大鼠血管TNF-α表达较A组上调(P<0.05)。B1组大鼠外周血CD4^+CD25^+Foxp3^+调节性T细胞比例较A组、B2组降低(P<0.05)。结论外周血nTreg在AS不同时期的变化,可能与TNF-α调节有关。

Objective To explore the immune regulation effect of peripheral blood natural regulatory T cell（nTreg）and the expression of tumor necrosis factor（TNF）-αin aortas during the progression of atherosclerosis（AS）.Methods Thirty-six male Sprague-Dawley（SD）rats（body weight 100 g±10 g）were randomly divided into,healthy control group（group A）,early stage atherosclerosis group（group B1）,late stage atherosclerosis group（group B2）,each group had12 rats.Rat atherosclerosis models were established by treating rats with celiac injection of vitamin D3 accompanied by high sucrose-high fat diet in this experiment.The frequency of CD4~＋CD25~＋Foxp3~＋regulatory T cell in peripheral blood was measured by fluorescence-activated cell sorter（FACS）in each group.Aortas were observed with HE staining for pathological changes.The expression of TNF-αin the rat aortic roots was detected by immunohistochemical assay.Results There was no plaque in the rat aortic roots in group A.There was fibrous plague in the rat aortic roots in group B1.There was atheromatous plague in the rat aortic roots in group B2.The expressions of TNF-αprotein in the rat aortic roots in group B1 and group B2 wwre higher than those in group A（P 〈0.05）.Peripheral frequency of CD4~＋CD25~＋Foxp3~＋regulatory T cell was decreased in group B1 compared with those in group A and group B2（P 〈0.05）.Conclusion The change of peripheral blood natural regulatory T cell may be associated with the TNF-αadjustment in different periods of atherosclerosis.