Hepatic stem cells: from inside and outside the liver?
Article first published online: 11 FEB 2004
Volume 37, Issue 1, pages 1–21, February 2004
How to Cite
Alison, M. R., Vig, P., Russo, F., Bigger, B. W., Amofah, E., Themis, M. and Forbes, S. (2004), Hepatic stem cells: from inside and outside the liver?. Cell Proliferation, 37: 1–21. doi: 10.1111/j.1365-2184.2004.00297.x
- Issue published online: 11 FEB 2004
- Article first published online: 11 FEB 2004
- Received 15 November 2003; revision accepted 1 December 2003
Abstract. The liver is normally proliferatively quiescent, but hepatocyte loss through partial hepatectomy, uncomplicated by virus infection or inflammation, invokes a rapid regenerative response from all cell types in the liver to perfectly restore liver mass. Moreover, hepatocyte transplants in animals have shown that a certain proportion of hepatocytes in foetal and adult liver can clonally expand, suggesting that hepatoblasts/hepatocytes are themselves the functional stem cells of the liver. More severe liver injury can activate a potential stem cell compartment located within the intrahepatic biliary tree, giving rise to cords of bipotential transit amplifying cells (oval cells), that can ultimately differentiate into hepatocytes and biliary epithelial cells. A third population of stem cells with hepatic potential resides in the bone marrow; these haematopoietic stem cells may contribute to the albeit low renewal rate of hepatocytes, but can make a more significant contribution to regeneration under a very strong positive selection pressure. In such instances, cell fusion rather than transdifferentiation appears to be the underlying mechanism by which the haematopoietic genome becomes reprogrammed.