Regeneration of Liver After Extreme Hepatocyte Loss Occurs Mainly via Biliary Transdifferentiation in Zebrafish
Regeneration of Liver After Extreme Hepatocyte Loss Occurs Mainly via Biliary Transdifferentiation in Zebrafish
复制标题
斑马鱼肝细胞极度丧失后的肝脏再生主要通过胆道转分化发生
DOI：
10.1053/j.gastro.2013.11.045
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发表时间：
2014-03-01
期刊：
影响因子：
29.4
通讯作者：
Luo, Lingfei
中科院分区：
文献类型：
--
作者：
He, Jianbo;Lu, Huiqiang;Luo, Lingfei
背景与目的：肝脏具有很高的再生能力，但目前尚不清楚大多数胆管细胞（特别是较大的胆管细胞）是否在再生肝脏中转分化为肝细胞。我们研究了这个过程如何有助于斑马鱼的肝再生。方法：使用标准的I-SceI大范围核酸酶转基因技术产生斑马鱼转基因系。Tg（lfabp：mCherry-NTR）cq 2动物的肝细胞通过给予甲硝唑消融。我们研究了转分化的胆管细胞肝细胞和标记物的表达，使用整体安装抗体染色，荧光原位杂交，和Cre/loxP为基础的遗传谱系追踪分析。利用胆细胞发育缺陷的斑马鱼幼鱼，探讨胆细胞在肝细胞再生中的作用。结果：在肝细胞极度丧失后，几乎所有的胆管细胞稳定地丧失其管状形态，增殖并表达肝细胞特异性标志物。基于Cre/loxP的诱导谱系追踪显示，新的肝细胞主要来自胆管细胞的转分化;这个过程需要Notch信号传导，进而激活胆管细胞中的Sox 9 b。在大多数胆管细胞中，早期内胚层和成肝细胞标志物的激活表明，胆汁转分化包括去分化成双能中间体的步骤。胆管细胞发育缺陷损害肝细胞再生。结论：使用我们的斑马鱼肝再生模型，我们发现胆管细胞可以转分化为肝细胞，并且是极端肝细胞损失后肝细胞再生的主要贡献者。
BACKGROUND & AIMS:The liver has high regenerative capacity, but it is not clear whether most biliary cells (particularly larger cholangiocytes) transdifferentiate into hepatocytes in regenerating liver. We investigated how this process might contribute to liver regeneration in zebrafish. METHODS: Zebrafish transgenic lines were generated using the standard I-SceI meganuclease transgenesis technique. Hepatocytes of the Tg(lfabp:mCherry-NTR) cq2 animals were ablated by the administration of metronidazole. We investigated transdifferentiation of biliary cells to hepatocytes and expression of markers using whole mount antibody staining, fluorescent in situ hybridization, and Cre/loxP-based genetic lineage tracing analyses. The role of biliary cells in hepatocyte regeneration was explored using zebrafish larvae with defects in biliary cell development. RESULTS:After extreme loss of hepatocytes, nearly all the biliary cells steadily lost their tubular morphology, proliferated, and expressed hepatocyte-specificmarkers. Cre/loxP-based inducible lineage tracing showed that new hepatocytes mainly arose from transdifferentiation of biliary cells; this process required Notch signaling and, in turn, activation of Sox9b in cholangiocytes. Activation of early endoderm and hepatoblast markers in most of the cholangiocytes indicated that biliary transdifferentiation includes a step of dedifferentiation into a bipotential intermediate. Defects in development of biliary cells impaired hepatocyte regeneration. CONCLUSIONS:Using our zebrafish liver regeneration model, we found that biliary cells can transdifferentiate into hepatocytes and are the major contributors to hepatocyte regeneration after extreme hepatocyte loss.