Sciot R, de Vos R, van Eyken P, van der Steen K, Moerman P, Desmet V J
Department of Pathology II, University Hospital St. Rafaël, Catholic University of Leuven, Belgium.
Liver. 1989 Apr;9(2):110-9. doi: 10.1111/j.1600-0676.1989.tb00387.x.
Using an indirect immunoperoxidase technique on frozen sections with the monoclonal antibody 96.5, we investigated the in situ distribution of melanotransferrin, a transferrin (Tf) and transferrin receptor (TfR) related glycoprotein, in human liver. Specimens included normal liver, liver in iron overload, hepatocellular carcinoma, angioma and foetal liver. On light microscopy, immunoreactivity was almost exclusively present on sinusoidal lining cells, apparently endothelial cells; the pattern was similar in normal and in iron-loaded liver. A gradient of more enhanced staining in acinar zone II and III was observed. The endothelial localization of the staining was supported by the positivity of the central vein endothelium and of the angiomas. Immunoelectron microscopy on three liver specimens showed positivity on sinusoidal endothelial cells but not on Ito and Kupffer cells. In addition, positivity on rough endoplasmic reticulum vesicles of some hepatocytes was also present. Four hepatocellular carcinomas showed an intense staining in tumour cells, 3 were weakly positive and 3 were negative. In the foetal livers, the central vein endothelium was positive from 21 weeks of gestation onward and additional positivity of zone III sinusoidal endothelial cells was present from 27 weeks on. The present results show that in the liver melanotransferrin has a localization different from Tf and the TfR. These latter molecules are predominantly localized in parenchymal cells. In addition, there does not appear to be a coordinate regulation secondary to iron storage, between melanotransferrin, Tf and the TfR. The observed gradient in the staining pattern in foetal and adult liver specimens further supports the heterogeneity of the endothelial cell population in the liver and suggests a developmental relationship between endothelial cells of sinusoids and central vein.
我们使用单克隆抗体96.5对冰冻切片进行间接免疫过氧化物酶技术，研究了人肝脏中黑素转铁蛋白（一种与转铁蛋白（Tf）和转铁蛋白受体（TfR）相关的糖蛋白）的原位分布。标本包括正常肝脏、铁过载肝脏、肝细胞癌、血管瘤和胎儿肝脏。在光学显微镜下，免疫反应几乎仅存在于窦状隙衬里细胞，显然是内皮细胞；正常肝脏和铁过载肝脏中的模式相似。在腺泡II区和III区观察到染色增强的梯度。中央静脉内皮和血管瘤的阳性结果支持了染色的内皮定位。对三个肝脏标本的免疫电子显微镜检查显示窦状内皮细胞呈阳性，而贮脂细胞和枯否细胞呈阴性。此外，一些肝细胞的粗面内质网囊泡也呈阳性。四个肝细胞癌在肿瘤细胞中显示出强烈染色，3个弱阳性，3个阴性。在胎儿肝脏中，中央静脉内皮从妊娠21周起呈阳性，从27周起III区窦状内皮细胞也呈阳性。目前的结果表明，在肝脏中黑素转铁蛋白的定位与Tf和TfR不同。后两种分子主要定位于实质细胞。此外，黑素转铁蛋白、Tf和TfR之间似乎不存在继发于铁储存的协同调节。在胎儿和成人肝脏标本中观察到的染色模式梯度进一步支持了肝脏内皮细胞群体的异质性，并提示了窦状隙内皮细胞和中央静脉内皮细胞之间的发育关系。
