Dose-Dependent Modulation of Tissue Factor Protein and Procoagulant Activity in Human Monocyte-Derived Macrophages by Oxidized Low Density Lipoprotein
Dose-Dependent Modulation of Tissue Factor Protein and Procoagulant Activity in Human Monocyte-Derived Macrophages by Oxidized Low Density Lipoprotein
复制标题
DOI：
10.5551/jat.7179
复制
发表时间：
2011-01-01
影响因子：
4.4
通讯作者：
Shah, Prediman Krishan
中科院分区：
文献类型：
--
作者：
Meisel, Simcha Ron;Xu, Xiao-Ping;Shah, Prediman Krishan
目的：氧化低密度脂蛋白（oxLDL）与巨噬细胞相互作用并参与动脉粥样硬化的发生。巨噬细胞也是动脉粥样硬化斑块内组织因子（TF）的主要来源，TF是一种膜结合糖蛋白受体，可触发体内凝血级联反应并促进斑块血栓形成。在这项研究中，我们测试的假设，oxLDL调节TF在人单核细胞衍生的巨噬细胞（MDMs）的表达方法：单核细胞分离自人血液中，允许分化为MDMs在8天的细胞培养，然后暴露于不同浓度的oxLDL的存在或不存在的脂多糖（LPS）。以人重组TF为标准品，采用一步法凝固法测定MDM的TF促凝活性（TF-PCA）。结果：5-10 μ g/mL的oxLDL可增加MDM细胞中TF-PCA、TF蛋白和mRNA的表达，而20-100 μ g/mL的oxLDL可抑制MDM细胞中TF-PCA、TF蛋白和mRNA的表达，即使在LPS刺激下也是如此。低浓度的oxLDL增强MDM中TF的表达，而较高浓度的oxLDL在基线和LPS刺激后均减弱TF的表达。TF-PCA和TF蛋白都遵循这种剂量反应模式，其之前是一致的mRNA变化。因此，我们已经证明了在MDM中通过oxLDL对TF蛋白和生物活性的调节。
Aim: Oxidized low-density lipoprotein (oxLDL) interacts with macrophages and is implicated in atherogenesis. Macrophages are also the major source within the atherosclerotic plaque of tissue factor (TF), the membrane-bound glycoprotein receptor that triggers the coagulation cascade in vivo and contributes to plaque thrombogenicity. In this study we tested the hypothesis that oxLDL modulates TF expression in human monocyte-derived macrophages (MDMs).Methods: Mononuclear cells were isolated from human blood, allowed to differentiate into MDMs during 8 days in cell culture, and then exposed to varying concentrations of oxLDL in the presence or absence of lipopolysaccharide (LPS). TF procoagulant activity (TF-PCA) of MDMs was measured by one-stage recalcification clotting assay using human recombinant TF as standard. TF protein was evaluated by Western blotting, and TF mRNA was determined by Northern blot analysis.Results: OxLDL at 5-10 mu g/mL increased TF-PCA, TF protein, and mRNA in MDMs, whereas 20-100 mu g/mL oxLDL inhibited TF-PCA, protein expression, and mRNA expression in these cells even in the face of LPS stimulation.Conclusions: Low concentrations of oxLDL enhance TF expression in MDMs, whereas higher concentrations attenuate TF expression both at baseline as well as following LPS stimulation. Both TF-PCA and TF protein follow this dose-response pattern that is preceded by concordant mRNA changes. Thus, we have demonstrated modulation by oxLDL of TF protein and bioactivity in MDMs.