氧化型低密度脂蛋白对外周血单核来源树突状细胞成熟及免疫功能的影响

目的 观测氧化型低密度脂蛋白(ox-LDL)对外周血单核来源的树突状细胞(DC)成熟及功能的影响,初步探讨其作用机理.方法 体外分离培养外周血单核来源的DC,按照处理方式不同分为4组,分别给予磷酸缓冲液(PBS)、低密度脂蛋白(LDL)、ox-LDL、肿瘤坏死因子a(TNF-a)刺激.随后进行流式细胞分析各组DC表面分子的表达情况.使用ELISA方法对培养上清中DC分泌的细胞凶子和趋化因子进行测定.使用FITC标记的葡聚糖检测DC吞噬抗原能力变化.使用Western blot方法对DC胞质内核冈子kB(NF-kB)、NF-kB抑制蛋白a(IkBa)的表达进行测定.结果 同空白对照组相比,经过ox-LDL处理后的外周血单核来源DC表达CIMO(22.3%比45.6%)、CD86 (25.9%比82.4%)均明显高,白介素12(31.43 pg/ml比126.73 pg/m1)、单核细胞趋化蛋白1(59.6ng/ml比116.3 ng/ml)分泌多,单核细胞炎性蛋白(MIP1)分泌无明显变化.同时处理后的DC抗原吞噬能力低(46.8%比10.7%),激活自体淋巴细胞增殖能力强(刺激指数4.5比5.7),免疫蛋白印迹实验表明,经ox-LDL处理后DC胞质IkBa的降解多,NF-kB表达高.结论 ox-LDL可以促进外周血单核来源的DC成熟,其机制与NF-kB抑制蛋白IkBa降解有关.

The effect of oxidized low-density lipoprotein on the maturation and its immune function of monocyte-derived dendritic cells

Objective To observe the effects of ox-LDL on monocle-derived dendritic cells.Methods DCs were derived from healthy donors and divided into four groups according to the method of stimulation.The cells of blank group,negative group,experimental group and positive group which were treaded with PBS,LDL,ox-LDL,TNF-a,individually.ox-LDL was added during the late stage of monocyte differentiation. Flow cytometry was used to analyze the cell surface markers and the endocytes of DCs.3H-TdR incorporation was used to measure the proliferation of syngeneie and allogeneic T cells.ELISA assay was used to measure IL-12,MCP-1 and MIP1 in cultured medium.Western blot analysis Was used to evaluate the content of IKBa and NF.KB of DCs.Resuits Addition of ox-LDL during the late stage of monocytes differentiation can upregulate the cell surface markers including CD40(22.3% vs.45.6%)and CD86 (25.9%VS.82.4%),increase the secretion of IL-12(31.43 pg/ml vs.126.73 pg/ml)and MCP-1(59.6 ng/ml vs.116.3 ng/ml),reduce DCs uptake capacity(46.8% vs.10.7%),enhance allogeneic T cells proliferation(SI:4.5 vs.5.7),promote IkBa degradation and upregulate the expression of NF-kB in DCs.Conclusion ox-LDL can promote the maturation of PBMCs-derived DCs by promoting IkBa degradation.