Theme |
Acute Liver Failure and Regenerative Medicine of the Liver |
Title |
Relationship Between Activation of Wnt Signaling Pathways and Development of Fetal Liver |
Author |
Sei Kakinuma |
Division of Stem Cell Therapy, Center for Stem Cell and Regenerative Medicine, Institute of Medical Science, The University of Tokyo |
[ Summary ] |
Hepatic stem cells exhibit active proliferative potential and bipotential differentiation into both hepatic and bile-epithelial lineages. Recently, these cells have been identified in mouse fetal liver. However, the molecular mechanisms of proliferation and differentiation in developing hepaticstem/progenitor cells remain unclear. We focused on Wnt signaling pathways as involved with candidate molecules engaged in development of hepatic stem/progenitor cells, and discussed the function of this pathway. Wnt ligands, Frizzled receptors, and downstream effectors are expressed in primary cells derived from mid-gestational fetal liver. Inhibition of canonical Wnt signaling pathway suppress in vitro proliferation of fetal hepatic cells. Canonical Wnt signaling pathways are temporally up-regulated in developing livers invivo. These studies suggest that the activation of Wnt signaling pathways are associated with the development of hepatic stem/progenitor cells in fetal livers. |