摘要
目的分析载脂蛋白E基因(APOE)对RAW264.7细胞内的TLR信号通路的调节作用。方法克隆鼠APOE基因并建立表达APOE的RAW264.7稳定细胞系,使用各种Toll样受体(Toll-like receptors,TLR)配体进行刺激,用报告基因化学发光检测转录因子活性,流式细胞仪检测细胞表面免疫分子。结果在LPS刺激下,APOE基因抑制NF-κB的活性(P<0.05),但对AP-1活性有促进作用(P<0.05);在PolyI:C刺激下,APOE促进NF-κB和AP-1两者的活性(P<0.05)。在PGN刺激时,APOE明显上调B7-H1的表达,但对CD86、PD-1、CD11c及Gr-1的表达有抑制作用。结论APOE基因可以调节TLR信号通路中NF-κB的活性,也可调节多个具有免疫调节功能的表面分子的表达,这样APOE可能具有免疫调节功能。
Objective To determine the effects of APOE on intracellular signal pathways mediated by different kinds of TLR. Methods We first cloned APOE gene, set up APOE tranfected stable cell line; and then detected the activity of both NF-κB and AP-1 transcription factors with chemiluminescence method. Using flow cytometric analysis, we investigated the expression of surface molecules in the APOE transfected RAW264. 7 upon exposing to LPS, PolyI ： C, PGN and BDNA. Results APOE not only affected the activity of NF-κB and AP-1 but also regulated the expression of eostimulatory molecules induced by different kinds of TLR ligands. Indeed, APOE transfeeted RAW264.7 showed higher activity of NF-κB and AP-I upon exposure to LPS and polyI ： C as compared with the control（P 〈0. 05） though NF-κB activity was little inhibited upon exposing to LPS（P 〈0. 05）. While APOE transfected RAW264.6 were stimulated by PGN, PolyI：C, LPS and BDNA respectively, APOE remarkably promoted the expression of B7-H1 induced by PGN; whereas the expression of CD86, PD-1, CDlle and Grl were lower in these APOE transfected stable cells. However, APOE did not effectively affect the expression of these costimulatory molecules induced by LPS, BDNA and PolyI：C. Conclusion APOE affects specifically the expression of eostimula tory molecules mediated by PGN and regulates the activity of NF - κB and AP - 1 , implying that APOE might be involved in the regulation of TLR-mediated immune responses.
出处
《基础医学与临床》
CSCD
北大核心
2008年第10期1015-1020,共6页
Basic and Clinical Medicine
基金
国家自然科学基金(30771967)
国家科技部基金(06C26211200695)
国家高技术研究发展计划(863计划)(2006AA020502)
天津市科委基金(07JCZDJC03300
06ZHCXSH04800)
关键词
APOE
TLR
免疫调节
转录因子
APOE
toll-like receptor
immune regulation
transcriptional factor
