The liver is a complex organ performing numerous vital physiological functions. For that reason, it possesses immense regenerative potential. The capacity for repair is largely attributable to the ability of its differentiated epithelial cells, hepatocytes and biliary epithelial cells, to proliferate after injury. However, in cases of extreme acute injury or prolonged chronic insult, the liver may fail to regenerate or do so suboptimally. This often results in life-threatening end-stage liver disease for which liver transplantation is the only effective treatment. In many forms of liver injury, bipotent liver progenitor cells are theorized to be activated as an additional tier of liver repair. However, the existence, origin, fate, activation, and contribution to regeneration of liver progenitor cells is hotly debated, especially since hepatocytes and biliary epithelial cells themselves may serve as facultative stem cells for one another during severe liver injury. Here, we discuss the evidence both supporting and refuting the existence of liver progenitor cells in a variety of experimental models. We also debate the validity of developing therapies harnessing the capabilities of these cells as potential treatments for patients with severe and chronic liver diseases.

中文翻译：

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肝损伤和修复中的肝祖细胞和成体细胞可塑性：已知和未知。


肝脏是一个复杂的器官，执行许多重要的生理功能。因此，它具有巨大的再生潜力。修复能力很大程度上归因于其分化的上皮细胞、肝细胞和胆管上皮细胞在损伤后的增殖能力。然而，在极度急性损伤或长期慢性损伤的情况下，肝脏可能无法再生或再生效果不佳。这通常会导致危及生命的终末期肝病，肝移植是唯一有效的治疗方法。在许多形式的肝损伤中，理论上双能肝祖细胞被激活作为肝脏修复的附加层。然而，肝祖细胞的存在、起源、命运、激活和对再生的贡献引起了激烈的争论，特别是因为肝细胞和胆管上皮细胞本身在严重肝损伤期间可能充当彼此的兼性干细胞。在这里，我们讨论各种实验模型中支持和反驳肝祖细胞存在的证据。我们还讨论了开发利用这些细胞的能力作为严重和慢性肝病患者的潜在治疗方法的有效性。