Histochemical study for apolipoprotein abnormalities in lipoprotein glomerulopathy

我们通过免疫电镜、电镜、脂质染色以及常规组织学观察证实，在脂蛋白肾小球病（LPG）及其实验模型中，特异性载脂蛋白（apo） E变异参与肾小球内脂蛋白血栓的形成。此外，我们还研究了脂蛋白血栓颗粒大小与血浆脂蛋白谱之间的关系。我们使用的活检标本分别来自apoE- sendai （Arg145Pro）、apoE缺失18个氨基酸和apoE- tokyo缺失3个氨基酸的LPG病例。我们还研究了apoE-Sendai病毒注入apoe -缺陷小鼠诱导的LPG模型的组织化学。我们利用抗人apoE抗体对活检标本和小鼠肾脏部分的速冻切片进行免疫过氧化物酶研究，并用倒立包埋法包埋Epon 812进行电镜观察。人和实验动物肾小球内脂蛋白血栓的脂质颗粒周围可见apoE阳性染色。为了明确脂蛋白血栓中颗粒的特征，用电镜和苏丹- iv染色观察了epon包埋块的连续切片。结果表明，脂蛋白血栓主要含有甘油三酯，甘油三酯由不饱和脂肪酸组成。在epon包埋过程中，对苯二胺的孵育增强了实验LPG中的发现。我们在电子显微镜下检查了肾小球内脂质颗粒的平均直径，并与血浆中的脂蛋白谱进行了比较。血管直径与全血浆甘油三酯/胆固醇比值及HDL有显著相关性（r=-0.80, p<0.01），与VLDL和LDL无显著相关性。此外，血浆和HDL中脂质颗粒较小、TG/Chol比值较高的患者为肾病或在6个月内发生肾病。

We clarified using immunoelectron microscopy and serial observations with electron microscopy and lipid stain as well as routine histology that specific apolipoprotein (apo) E variants are involved in the formation of intraglomerular lipoprotein thrombi in cases of lipoprotein glomerulopathy (LPG) and its experimental model. In addition, we investigated the relationship between sizes of particles in lipoprotein thrombi and lipoprotein profile in plasma.1. We use biopsy specimens from cases of LPG having apoE-Sendai(Arg145Pro), apoE with 18 amino acid deletion and apoE-Tokyo with 3 amino acid deletion, respectively. We also investigated histochemistry of a LPG model induced by the injection of apoE-Sendai virus into apoE-deficient mice.2. We applied immunoperoxidase study with anti-human apoE antibody to snap-frozen sections of biopsy specimens and mouse kidney portions, and embedded the sections in Epon 812 by the handstand-embedding method for electron microscopic observation. Positive stain of apoE were seen around lipid granules in the intraglomerular lipoprotein thrombi of both human and experimental LPG.3. To define the characteristics of particles in lipoprotein thrombi, serial sections of Epon-embedded blocks were observed with electron microscopy and Sudan-IV stain. The results showed that lipoprotein thrombi mainly included triglycerides, which were composed of unsaturated fatty acids. The findings in experimental LPG were enhanced by incubation in p-phenylenediamine during Epon-embedding.4. We examined the mean diameters of intraglomerular lipid particles under electron microscopy and compared with lipoprotein profile in plasma. The diameters were significantly correlated with triglycerides/cholesterol ratios in whole plasma and in HDL fraction (r=-0.80, p<0.01) but not in VLDL or LDL.In addition, the cases showing smaller lipid granules and higher TG/Chol ratios in plasma and in HDL were nephrotic or became nephrotic within 6 months.