Department of Medical Pathomorphology, Medical University of Bialystok, Bialystok, Poland.
Adv Med Sci. 2011;56(2):172-9. doi: 10.2478/v10039-011-0037-8.
Very interesting reports have appeared lately on the role of liver progenitor/oval cells in the morphogenesis and development of nonalcoholic steatohepatits (NASH) in adult patients and experimental animals. However, no literature data concerning pediatric patients have been available. Therefore, the purpose of the study was to evaluate the ultrastructure of the population of liver progenitor/oval cells in the biopsy material from children with previously clinocopathologically diagnosed NASH.
MATERIAL/METHODS: Electron-microscopic examinations were conducted on fresh tissue samples collected from 10 children with NASH (aged 2-14 years), which were fixed with a solution of 2% paraformaldehyde and 2.5% glutaraldehyde in 0.1 M cacodylate buffer.
Ultrastructural examinations of the liver progenitor/oval cells in children with NASH show a quite prominent number of these cells, especially their two types, hepatic progenitor cells (HPCs) and intermediate hepatocyte-like cells (IHCs), with intermediate bile-like cells being the least frequent. They were found to occur single or in clusters of two, seldom of three, and frequently in the areas of advanced liver fibrosis or close to them. Many times, these cells were accompanied by hepatocytes showing a varying degree of death, to total cell disintegration. Interesting was the presence of activated nonparenchymal liver cells, i.e. Kupffer cells/macrophages and hepatic stellate cells, frequently found to adhere to the hepatic oval cells.
The current study suggests a marked involvement of the population of liver progenitor/oval cells, mainly HPCs and IHCs, in the development of nonalcoholic steatohepatitis in pediatric patients, especially in fibrosis progression.
最近有一些非常有趣的报告指出，肝祖细胞/卵圆细胞在成年患者和实验动物的非酒精性脂肪性肝炎（NASH）的形态发生和发展中起作用。然而，目前尚无关于儿科患者的文献数据。因此，本研究的目的是评估经临床病理诊断为 NASH 的儿童肝祖细胞/卵圆细胞群体在活检材料中的超微结构。
材料/方法：对 10 例 NASH 儿童（年龄 2-14 岁）的新鲜组织样本进行电子显微镜检查，这些样本用 2%多聚甲醛和 2.5%戊二醛在 0.1M 卡可酸缓冲液中固定。
对 NASH 儿童肝祖细胞/卵圆细胞的超微结构检查显示，这些细胞数量相当多，尤其是两种类型的肝祖细胞（HPCs）和中间肝细胞样细胞（IHCs），而中间胆样细胞最少见。它们单独或两个一组出现，很少三个一组，并且经常出现在肝纤维化或接近纤维化的区域。很多时候，这些细胞伴随着不同程度死亡的肝细胞，甚至导致细胞完全解体。有趣的是，存在活化的非实质细胞，即库普弗细胞/巨噬细胞和肝星状细胞，它们经常附着在肝卵圆细胞上。
本研究表明，肝祖细胞/卵圆细胞群体，主要是 HPCs 和 IHCs，在儿科患者的非酒精性脂肪性肝炎，尤其是纤维化进展中明显参与。
