FOXP3基因对ApoE-knockout小鼠动脉粥样硬化的影响

Effects of FOXP3 on the progression of atherosclerosis plaque in ApoE-knock out mice

目的:研究FOXP3对ApoE-/-小鼠动脉粥样硬化形成的影响。方法:构建FOXP3-siRNA慢病毒载体,免疫磁珠分选Foxp3+ CD4+ CD25+ Treg细胞。利用Westernblot方法对构建的载体进行功能性研究。实验动物分为阴性对照组、阳性对照组、FOXP3-siRNA慢病毒注射组和Foxp3+ CD4+ CD25+ Treg细胞注射组。比较各组小鼠的斑块面积和不同组织Foxp3+ CD4+ CD25+ Treg细胞的数目和功能;利用ELISA法检测各组脾细胞炎性因子浓度;利用RT-PCR和Westernblot分析不同组织中FOXP3转录水平和Foxp3蛋白表达水平。结果:与对照组和Foxp3+ CD4+ CD25+ Treg细胞注射组比较,FOXP3-siRNA慢病毒注射组小鼠斑块面积明显增加(P<0.05);Foxp3+ CD4+ CD25+Treg细胞的数目显著减少(P<0.05),功能下降;Foxp3蛋白表达和FOXP3转录水平降低(P<0.05)。与对照组和FOXP3-siRNA慢病毒注射组比较,输注Foxp3+ CD4+ CD25+ Treg细胞组斑块面积显著减小(P<0.01);Foxp3+ CD4+ CD25+ Treg细胞的数目显著增加(P<0.01),功能增强;Foxp3蛋白表达和FOXP3转录水平增高(P<0.01)。结论:FOXP3可能通过调控体内炎症反应而产生抗动脉粥样硬化作用。

AIM： To explore effects of FOXP3 on the progression of atherosclerosis plaque in hypercholesterolemic apoliprotein（apo）E -/- mice. METHODS： At 8 weeks of age, 32 male ApoE -/- mice were randomly divided into four groups of eight. Labeled： negative control group, posi- tive control group, small interfering RNA （siRNA） group, and regulatory T cells transfer （Tregs） group. Lentivirusmediated （siRNA） identified its function by Western blot was used to knock down FOXP3 and Foxp3^high＋ CD4^＋ CD25^＋ Tregs acquired through magnetic activated cell sorting adoptive transfer assays in high fat diet ApoE -/- mice were done. The resulting atherosclerotic lesions were assessed by determining the number and function of CD4^＋ CD25^＋ Tregs, FOXP3 transcript levels and investigating the expression of Foxp3 protein in different tissues. Inflammatory cytokines were determined by ELISA. RESULTS： Animals treated with siRNA of FOXP3 showed a significant increase in atherosclerotic lesion formation and a reduction in the number and function of Foxp3^＋ CD4^＋ CD25^＋ Tregs compared with other groups. Transfer of Foxp3^high＋ CD4^＋ CD25^＋ Tregs significantly decreased atherosclerotic plaque formation and increased the number and function of Foxp3^＋ CD4^＋ CD25^＋ Tregs. Foxp3 protein levels and FOXP3 transcript levels were lowest in the siRNA group, and were highest in tissues from the Tregs transfer group. CONCLU-SION： FOXP3 plays an important role in regulating the inflammatory response within the atherosclerotic lesion. It can inhibit significant the progression of the atherosclerosis plaque in ApoE-/- mice.