Gibson J C, Rubinstein A, Brown W V, Ginsberg H N, Greten H, Norum R, Kayden H
Arteriosclerosis. 1985 Jul-Aug;5(4):371-80. doi: 10.1161/01.atv.5.4.371.
Apolipoprotein (apo) E-containing subfractions of very low density lipoprotein (VLDL), intermediate density lipoprotein (IDL), and high density lipoprotein (HDL) have been described in normolipidemic and hyperlipidemic subjects. These lipoproteins exist, however, in the presence of large amounts of apo A-I- and apo B-containing lipoproteins so that it has been difficult to assess the independence of these apo E-containing subclasses from the major lipoprotein classes. The present study has approached this question by taking advantage of three hypolipidemic states in which one or more of the major apolipoproteins is deficient or absent. After separating lipoproteins from whole plasma by molecular sieve chromatography followed by radioimmunoassay of column fractions, we found that two subjects with abetalipoproteinemia had no apo E-containing lipoproteins the size of VLDL or IDL and all the plasma apo E was in a fraction of large HDL. Two subjects with Tangier disease and two with familial apo A-I/C-III deficiency had extremely low levels of HDL cholesterol and of apo A-I-containing lipoproteins. In spite of the absence of classical HDL, a major fraction of apo E-containing lipoproteins was reproducibly observed at the elution volume characteristic of large HDL and was identical to that found in normal subjects. These data thus suggest the existence of apo E-containing lipoproteins that are the size of HDL and are not dependent upon the presence of either apo B or apo A-I. While studies in normal subjects indicate that apo E is associated with other apolipoproteins in HDL, further investigations will be needed to determine the full composition of these apo E-containing lipoproteins in the lipoprotein-deficient patients described in this report.
在血脂正常和高脂血症患者中，已描述了极低密度脂蛋白（VLDL）、中间密度脂蛋白（IDL）和高密度脂蛋白（HDL）中含载脂蛋白（apo）E的亚组分。然而，这些脂蛋白存在于大量含apo A-I和apo B的脂蛋白中，因此难以评估这些含apo E的亚类与主要脂蛋白类别的独立性。本研究利用三种低脂血症状态来解决这个问题，在这些状态中，一种或多种主要载脂蛋白缺乏或缺失。通过分子筛色谱法从全血中分离脂蛋白，然后对柱馏分进行放射免疫测定，我们发现两名无β脂蛋白血症患者没有VLDL或IDL大小的含apo E的脂蛋白，所有血浆apo E都存在于大HDL的一个馏分中。两名患有Tangier病的患者和两名患有家族性apo A-I/C-III缺乏症的患者HDL胆固醇和含apo A-I的脂蛋白水平极低。尽管没有典型的HDL，但在大HDL特征性的洗脱体积处可重复观察到大部分含apo E的脂蛋白，且与正常受试者中发现的相同。因此，这些数据表明存在HDL大小的含apo E的脂蛋白，且不依赖于apo B或apo A-I的存在。虽然对正常受试者的研究表明apo E与HDL中的其他载脂蛋白相关，但需要进一步研究来确定本报告中所述脂蛋白缺乏患者中这些含apo E的脂蛋白的完整组成。
