de Bruijn W C, Emeis J J, Vermeer B J
Artery. 1980;8(3):281-7.
Immuno-cytochemical characterization of human Low-Density Lipoproteins (LDL) is performed by the reaction between colloidal gold particles, being saturated with rabbit-anti-human apoprotein-B, and human LDL-particles, attached to binding-sites on cultured fibroblasts cell membranes. In conventional transmission electronmicrographs (CTEM) the 5-10 nm colloidal-gold particles are observed by contrast at the plasma membranes, although the LDL-particles themselves remained uncontrasted by the classical post-fixation procedures. Post-fixation procedures using the OsO4 plus K4Fe (CN)6 combination did not improve the LDL-particle contrast sufficiently. Application of both glutaraldehyde fixation plus tannic acid and post-fixation with the OsO4 plus K4Fe (CN)6 combination enhanced the contrast sufficiently to visualize single particles on the fibroblasts outer cell surface. The presence of colloidal-gold particles attached to some of these contrasted structures on the plasma membranes characterize the particles as LDL. However, not all particles visualized on the plasma membrane do contain the attached gold particles. The presence of the gold is shown by X-ray microanalysis of the attached contrasted particles. In scanning electron microscopic images (SEM), the total surface of the fibroblasts was covered with numerous small particles. Several particles were identified by the applied X-ray microanalysis as LDL-particles by their gold content, however, others failed to do so.
人低密度脂蛋白（LDL）的免疫细胞化学特性通过以下反应进行：用饱和兔抗人载脂蛋白B的胶体金颗粒与附着在培养的成纤维细胞膜结合位点上的人LDL颗粒发生反应。在传统透射电子显微镜图像（CTEM）中，尽管LDL颗粒本身在经典的后固定程序中仍未显影，但通过对比可在质膜上观察到5-10纳米的胶体金颗粒。使用OsO4加K4Fe(CN)6组合的后固定程序不能充分提高LDL颗粒的对比度。应用戊二醛固定加单宁酸以及用OsO4加K4Fe(CN)6组合进行后固定可充分增强对比度，从而在成纤维细胞外表面上可视化单个颗粒。附着在质膜上这些显影结构上的胶体金颗粒表明这些颗粒为LDL。然而，并非所有在质膜上可视化的颗粒都含有附着的金颗粒。通过对附着的显影颗粒进行X射线微分析可显示金的存在。在扫描电子显微镜图像（SEM）中，成纤维细胞的整个表面覆盖着许多小颗粒。通过应用的X射线微分析，一些颗粒因其金含量被鉴定为LDL颗粒，然而，其他颗粒则未被鉴定出来。
