氧化性低密度脂蛋白对人单个核细胞Toll样受体表达及炎症介质的影响

Regulatory Effects of Oxidatively Modified Low-density Lipoprotein on the Expression of Toll-like Receptor Gene and Cytokine Production in Human Peripheral Blood Mononuclear Cells

目的:探讨氧化性低密度脂蛋白(ox-LDL)对单个核细胞Toll样受体1～10(TLR1～10)表达的影响及对炎症因子TNF-α、IL-6的调控作用。方法:用逆转录-聚合酶链反应检测健康人单个核细胞中TLR1～10 mRNA的组成型表达;用实时定量-聚合酶链反应检测ox-LDL刺激单个核细胞后,TLR1～10mRNA表达的变化;结合抗体阻断实验,用酶联免疫吸附法(ELISA)检测培养上清液中TNF-α和IL-6的含量。结果:人单个核细胞有TLR1～10 mRNA的组成型表达,ox-LDL刺激可上调人单个核细胞TLR2、TLR4 mRNA的表达。经ox-LDL刺激后,单个核细胞分泌TNF-α、IL-6上升,受体阻断剂阻断TLR2、TLR4后,可以减少ox-LDL诱导的TNF-α、IL-6分泌。结论:ox-LDL可能是TLRs的内源性配体,ox-LDL可通过TLR信号通路调节单个核细胞炎性细胞因子的生成。

Objective： To investigate the regulatory effects of oxidatively modified low-density fipoprotein （ox-LDL） on the expression of Toll-like receptors （TLRs） gene and the concentrations of tumor necrosis factor-α and interferon-6 in Human peripheral blood mononudear cells. Methods： Constitutive expression of TLR1 - 10 mRNA in human peripheral blood mononudear cells was examined with reverse transcriptase-polymerase chain reaction, while the alterations of TLR1 -10 mRNA expression in human peripheral blood mononuclear cells were evaluated by real-time quantitative polymerase chain reaction. The concentrations of tumor necrosis factor-α （TNF-α） and interferon-6 （IL-6） were measured by enzyme-linked immuno sorbent assay （ELISA）. The anti-TLR mAbs were used to block the mononudear cells for 30 rain, ox-LDL was used to stimulate the cells. Rusults： TLR1- 10 mRNA were expressed in human peripheral blood mononuclear cells. The expression of TLR2, TLR4 mRNA were strongly up-regulated by ox-LDL. The concentrations of TNF-α,IL-6 were 111.99±14.40 and 837.23±116：12 after ox- LDL stimulation, which significantly higher than that in the control experiment （59.96±8.80 and 572.48±66.74 , respectively, both of them P〈0.01 ）. The concentrations of TNF-α,IL-6 （77.86±12.21 and 679.19±47.48, respectively. ） were lower than that in the cells stimulated by ox-LDL （both of them P〈0.01 ） after the mononuclear cells were blocked by anti-TLR2 mAb and anti-TLR4 mAb. Conclusions： Ox-LDL may be an endogenous ligand of TLRs and it can regulate the release of inflammation cytokines from human peripheral blood mononuclear cells through TLR signal way.