载脂蛋白A-I对树突状细胞表型及功能影响

Regulation on phenotypic and functional maturation of dendritic cells by apolipoprotein A-I

目的:探讨载脂蛋白A-I(ApoA-I)对人外周血树突状细胞(PBDC)及体外培养的单个核诱导的树突状细胞(MD-DC)的影响及其机制。方法:采用免疫磁珠法,直接分离PB-DC或通过GM-CSF,IL-4诱导生成MDDC,DC经ApoA-I,LPS或TNF-α刺激后,用流式细胞技术(FCM)检测树突状细胞表面协同刺激分子表达的变化及细胞的吞噬能力;酶联免疫吸附法(ELISA)检测DC分泌的细胞因子;CFSE法检测经刺激后DC对T细胞增殖的影响。结果:分离高纯度PBDC,并成功诱导生成未成熟MDDC;经FCM检测,ApoA-I刺激后的PBDC和MDDC膜表面CD83分子表达上调,同时MDDC表面的CD40、CD86及MHC-Ⅱ分子的表达均增强;吞噬能力减弱;IL-12和TNF-α的分泌增加;并且可以诱导Th细胞的增殖。结论:在体外ApoA-I可以诱导PBDC和MDDC的成熟、活化,刺激其分泌细胞因子,发挥其免疫应答中抗原呈递,促进Th分化的作用;通过该作用ApoA-I可能参与了动脉粥样硬化的发生,发展中的免疫应答。

AIM：To investigate the effects of apolipoprotein A-I （ApoA-I） on the peripherial blood dendritic cell （PBDC） and monocyte derived DC （MDDC） in vitro.METHODS：Isolate PBDC or monocyte by cell isolation kit,monocyte were induced to MDDC by treated with GM-CSF plus IL-4 for 6 days,and then collect PBDC and MDDC treated them with apoA-I,LPS or TNF-α for 24 hours.Then check the cell surface marker and phagocytic capacity by flow cytometry.ELISA was used to detect the levels of cytokine secretion.T cells were stained with CFSE and T cell proliferation was assessed by flow cytometry.RESULTS：Collect the PBDC and MDDC with high purity.In the presence of ApoA-I,the surface markers on MDDC,such as CD40,CD86 and MHC-Ⅱ,were up-regulated which were detected by flow cytometry.CD83 expression on both PBDC and MDDC was remarkably increased.ApoA-I DC demonstrated decreased the phagocytic capacity.ApoA-I also stimulated MDDC to produce IL-12 and TNF-α.Furthermore,ApoA-I can induce considerable Th cell proliferation.CONCLUSION：ApoA-I can induce the maturation and activation of MDDC and PBDC,including the cytokine secretion,specific antigen presentation and T cell proliferation and decreasing the phagocytic capacity.Therefore,ApoA-I may attribute to the immune response in AS process.