Centre for Diabetes, Barts and The London School of Medicine and Dentistry, Queen Mary University of London, London, UK.
Hepatology. 2010 Mar;51(3):1017-26. doi: 10.1002/hep.23483.
Here, we investigate the clonality and cells of origin of regenerative nodules in human liver cirrhosis using mitochondrial DNA (mtDNA) mutations as markers of clonal expansion. Mutated cells are identified phenotypically by deficiency in the entirely mtDNA encoded cytochrome c oxidase (CCO) enzyme by histochemical and immunohistochemical methods. Nodules were classified as either CCO-deficient or CCO-positive, and among 526 nodules from 10 cases, 18% were homogeneously CCO-deficient, whereas only 3% had a mixed phenotype. From frozen sections, hepatocytes were laser-capture microdissected from several sites within individual CCO-deficient nodules. Mutations were identified by polymerase chain reaction sequencing of the entire mtDNA genome. In all cases except for one, the nodules were monoclonal in nature, possessing up to four common mutations in all hepatocytes in a given nodule. Moreover, the identification of identical mutations in hepatic progenitor cells abutting CCO-deficient nodules proves that nodules can have their origins from such cells.
These data support a novel pathway for the monoclonal derivation of human cirrhotic regenerative nodules from hepatic progenitor cells.
在这里，我们使用线粒体 DNA（mtDNA）突变作为克隆扩增的标志物，研究人类肝硬化再生结节的克隆性和起源细胞。通过组织化学和免疫组织化学方法，通过缺乏完全由 mtDNA 编码的细胞色素 c 氧化酶（CCO）酶的表型特征来鉴定突变细胞。结节分为 CCO 缺乏或 CCO 阳性，在 10 例中的 526 个结节中，18%是均匀 CCO 缺乏，而只有 3%具有混合表型。从冷冻切片中，使用激光捕获微切割技术从单个 CCO 缺乏结节的多个部位分离肝细胞。通过聚合酶链反应对整个 mtDNA 基因组进行测序来鉴定突变。除了一个病例外，所有病例的结节均为单克隆性，在给定的结节中所有肝细胞中最多存在四种共同突变。此外，在毗邻 CCO 缺乏结节的肝祖细胞中鉴定出相同的突变证明结节可以起源于这些细胞。
这些数据支持了肝祖细胞从人类肝硬化再生结节中单克隆衍生的新途径。
