Fernandez Jose A, Deguchi Hiroshi, Banka Carole L, Witztum Joseph L, Griffin John H
From the Department of Molecular and Experimental Medicine, The Scripps Research Institute, La Jolla, CA (J.A.F., H.D., J.H.G.); and Department of Medicine, University of California San Diego (C.L.B., J.L.W., J.H.G.).
Arterioscler Thromb Vasc Biol. 2015 Mar;35(3):570-2. doi: 10.1161/ATVBAHA.114.304938. Epub 2014 Dec 30.
This study was conducted to resolve the striking controversy between our previous report that high-density lipoprotein (HDL) enhances activated protein C (APC)/protein S anticoagulant actions and a subsequent, contradicting report that HDL lacks this activity.
When fresh HDL preparations from 2 laboratories were subjected to Superose 6 column chromatography, fractions containing HDL-enhanced APC:protein S anticoagulant actions in clotting assays, thereby validating our previous report. Moreover, the ability of HDL to enhance the anticoagulant actions of APC:protein S was neutralized by anti-apoAI antibodies, further indicating that the activity is because of HDL particles and not because of contaminating phospholipid vesicles. Density gradient subfractionation studies of HDL showed that large HDL subfractions (densities between 1.063 and 1.125 g/mL) contained the APC:protein S-enhancing activity. Fresh HDL stored at 4°C gradually lost its anticoagulant enhancing activity for 14 days, indicating moderate instability in this activity of purified HDL.
These studies conclusively demonstrate that freshly prepared HDL fractions possess anticoagulant activity. Fractions from Superose 6 columns that contain HDL reproducibly enhance APC:protein S anticoagulant activity, consistent with the hypothesis that HDL has antithrombotic activity and with the observation that low HDL levels are found in male venous thrombosis patients. Understanding the basis for this activity could lead to novel therapeutic approaches to regulate venous thrombosis.
本研究旨在解决我们之前的报告（高密度脂蛋白（HDL）增强活化蛋白C（APC）/蛋白S抗凝作用）与随后一份矛盾报告（HDL缺乏此活性）之间的显著争议。
当对来自2个实验室的新鲜HDL制剂进行Superose 6柱色谱分析时，在凝血试验中含有HDL增强的APC：蛋白S抗凝作用的组分，从而验证了我们之前的报告。此外，HDL增强APC：蛋白S抗凝作用的能力被抗载脂蛋白AI抗体中和，进一步表明该活性是由于HDL颗粒而非污染的磷脂囊泡。HDL的密度梯度亚分级研究表明，大的HDL亚组分（密度在1.063至1.125 g/mL之间）含有APC：蛋白S增强活性。在4°C储存的新鲜HDL在14天内逐渐丧失其抗凝增强活性，表明纯化的HDL的这种活性具有中等不稳定性。
这些研究最终证明，新鲜制备的HDL组分具有抗凝活性。来自Superose 6柱的含有HDL的组分可重复性地增强APC：蛋白S抗凝活性，这与HDL具有抗血栓形成活性的假设以及男性静脉血栓形成患者中HDL水平较低的观察结果一致。了解这种活性的基础可能会导致调节静脉血栓形成的新治疗方法。
