Kotani K, Maekawa M, Kanno T, Kondo A, Toda N, Manabe M
Department of Laboratory Medicine, Hamamatsu University School of Medicine, Shizuoka, Japan.
Biochim Biophys Acta. 1994 Nov 17;1215(1-2):121-5. doi: 10.1016/0005-2760(94)90100-7.
We developed a sensitive enzyme-linked immunosorbent assay (ELISA) for detection of malondialdehyde-modified low-density lipoprotein (MDA-LDL) in human serum. A monoclonal antibody against MDA-LDL (ML25) used in our method recognized not only MDA-LDL but also other MDA-modified proteins. However, MDA-LDL was able to be detected specifically by using a combination of ML25 and an antibody specific for apolipoprotein B (apo B) (AB16), which was conjugated with beta-galactosidase. Using this method, measurable amounts of MDA-LDL were detected in the sera of 40 healthy individuals. MDA-LDL was observed to be mainly distributed in the human LDL fraction separated by density gradient ultracentrifugation, while in each lipoprotein subfraction the largest amount of MDA-LDL per protein was found at a subfraction between LDL and HDL. The particle size of LDL in this fraction was smaller than that of LDL in the main LDL fraction, as assessed by electrophoresis. In addition, LDL oxidized by Cu2+ was also detectable with this method. We conclude that our method is sensitive and specific for MDA-LDL and might be useful for investigating MDA-LDL in the human circulation.
我们开发了一种灵敏的酶联免疫吸附测定法（ELISA），用于检测人血清中的丙二醛修饰的低密度脂蛋白（MDA-LDL）。我们方法中使用的抗MDA-LDL单克隆抗体（ML25）不仅能识别MDA-LDL，还能识别其他MDA修饰的蛋白质。然而，通过将ML25与特异性针对载脂蛋白B（apo B）的抗体（AB16）结合使用，能够特异性检测MDA-LDL，该抗体与β-半乳糖苷酶偶联。使用这种方法，在40名健康个体的血清中检测到了可测量量的MDA-LDL。通过密度梯度超速离心分离的人LDL组分中观察到MDA-LDL主要分布在其中，而在每个脂蛋白亚组分中，每蛋白质中MDA-LDL含量最高的是在LDL和HDL之间的一个亚组分中。通过电泳评估，该组分中LDL的粒径小于主要LDL组分中LDL的粒径。此外，用这种方法也能检测到被Cu2+氧化的LDL。我们得出结论，我们的方法对MDA-LDL灵敏且特异，可能有助于研究人体循环中的MDA-LDL。
