C反应蛋白和脂多糖致单核细胞核因子-κB活化的时间效应

Nuclear Factor-κB Activation in Human Monocytes Stimulated by C-Reactive Protein and Lipopolysaccharide

目的:观察C反应蛋白(CRP)和脂多糖(LPS)刺激人外周血单核细胞核因子-κB(NF-κB)活化及白细胞介素-6(IL-6)表达,探讨CRP/NF-κB在动脉粥样硬化(A S)致病机制中的作用。方法:密度梯度离心法分离人外周血单核细胞,免疫细胞化学观察CRP和LPS致单核细胞NF-κB p65活化的时间效应,EL ISA法观察IL-6产生的时间效应。结果:CRP和LPS刺激单核细胞NF-κB活化呈时间依赖性,开始活化的时间在刺激后30 m in,高峰分别在2 h与1 h;CRP和LPS刺激单核细胞合成IL-6呈时间依赖性,开始合成的时间分别在刺激后4 h与2 h,高峰在24 h,其合成出现在核因子-κB活化后。结论:CRP和LPS激活单核细胞NF-κB信号途径,并诱导IL-6产生。

Objective ： To observe the influence of c-reactive protein（CRP）and lipopolysaccharide（LPS） On nuclear factor-kB（NF-kB）activation and interleukin-6（IL-6） production in human monocytes ,to investigate the role of CRP/NF- kB in atherosclerosis. Methods ：Monocytes were isolated from blood of healthy volunteers by the Ficoll density gradient and stimulated by CRP （20 mg/L） or LPS（10 μg/L） at indicated time points （0,2,4,8,16 and 24 h）, Measurements of IL-6 were performed from supernatants of cultured medium by ELISA;activation of NF-kB were evaluated by immunocytochemical method after coincubated with 20 mg/L CRP and 10 μg/L LPS for 0. 5-2 h. Results：NF-kB nuclear translocation in monocytes increased significantly after 30 minutes of incubation with CRP and LPS. CRP and LPS stimulated NF-kB activity in human monocytes in a time-dependent manner,the peak expression was 2 h and 1 h,respectively. CRP and LPS induced the rapid release of IL-6,with significantly elevated levels in cultured supernatants at 4 h and 2 h, reaching peaks at 24 h. The effects of CRP and LPS on IL-6 release of monocytes were time dependent. NF-kB activated before IL-6 production in monocytes, Conclusion：CRP and LPS can stimulate IL-6 expression in human monocytes at least in part through NF-kB signal transduction. It shows that CRP may play a direct role in the pathogenesis of inflam- mation/atherosclerosis.