肝内外干/祖细胞参与肝再生的研究进展

Participation of intra-and extrahepatic stem/progenitor cells in liver regeneration: recent advances

肝再生是指由损伤刺激(手术、创伤、中毒、感染、坏死等)引起的受损肝组织迅速增生使残肝体积增大,质量增加。根据肝损伤原因和损伤的程度肝再生可以主要分为3个不同的层次:肝细胞主导的肝再生、肝内干/祖细胞介导的肝再生和肝外干/祖细胞参与的肝再生。当肝脏受到轻至中度损伤时,肝脏再生通常由成熟的肝细胞所参与完成;当肝脏受到严重的损伤或肝细胞的增殖受到明显抑制时,肝干/祖细胞将参与肝再生过程。除了肝内干细胞参与作用外,肝外的骨髓来源干细胞,内皮祖细胞来源的干细胞均参与了肝再生,但其具体机制目前尚不明了。笔者就肝再生最新关注的焦点,尤其是干/祖细胞参与的肝再生和其潜在的临床应用进行综述。

Liver regeneration refers to the rapid proliferation of impaired liver tissue caused by injurious stimulus （surgery trauma, poisoning, infection, and necrosis, etc.） to increase the volume and weight of the remnant liver. Liver regeneration can be divided into three major levels according to the cause and severity of the injury： hepatocyte dominant regeneration, intrahepatic stem/progenitor cells mediated regeneration, and extrahepatic stem/ progenitor cells participative regeneration. Liver regeneration is usually completed by division of the mature liver ceils after the liver undergoing mild to moderate injuries. However, when the liver is severely damaged or the proliferation of hepatocytes is strongly inhibited, liver stem/progenitor cells will participate in the liver regeneration process. Besides the participation of the intrahepatic stem cells, the extrahepatic bone marrow- derived stem cells and stem cells reprogrammed from endothelial progenitor cells are also involved in liver regeneration, but the detailed mechanism remains unclear. Here, the authors address the latest focuses on liver regenerationj especially on the stem/progenitor cells participated liver regeneration and its potentialclinical application.