ZFIN ID: ZDB-PUB-131119-47
Extensive Conversion of Hepatic Biliary Epithelial Cells to Hepatocytes after Near Total Loss of Hepatocytes in Zebrafish
Choi, T.Y., Ninov, N., Stainier, D.Y., and Shin, D.
Date: 2014
Source: Gastroenterology 146(3): 776-88 (Journal)
Registered Authors: Choi, Tae-Young, Ninov, Nikolay, Shin, Donghun, Stainier, Didier
Keywords: oval cells, liver regeneration, dedifferentiation, stem cells
MeSH Terms: Ablation Techniques; Animals; Biliary Tract/cytology*; Cell Death/drug effects; Cell Proliferation* (all 17) expand
PubMed: 24148620 Full text @ Gastroenterology
ABSTRACT

Background & Aims

Biliary epithelial cells (BECs) are considered to be a source of regenerating hepatocytes when hepatocyte proliferation is compromised. However, there is still controversy about the extent to which BECs can contribute to the regenerating hepatocyte population, and thereby to liver recovery. To investigate this issue, we established a zebrafish model of liver regeneration in which the extent of hepatocyte ablation can be controlled.

Methods

Hepatocytes were depleted by administration of metronidazole to Tg(fabp10a:CFP-NTR) animals. We traced the origin of regenerating hepatocytes using short-term lineage tracing experiments as well as the inducible Cre/loxP system; specifically, we utilized both a BEC tracer line Tg(Tp1:CreERT2) and a hepatocyte tracer line Tg(fabp10a:CreERT2). We also examined BEC and hepatocyte proliferation as well as liver marker gene expression during liver regeneration.

Results

BECs gave rise to most of the regenerating hepatocytes in larval and adult zebrafish after severe hepatocyte depletion. Following hepatocyte loss, BECs proliferated as they dedifferentiated into hepatoblast-like cells; they subsequently differentiated into highly proliferative hepatocytes that restored the liver mass. This process was impaired in zebrafish wnt2bb mutants; in these animals, hepatocytes regenerated but their proliferation was greatly reduced.

Conclusions

BECs contribute to regenerating hepatocytes following substantial hepatocyte depletion in zebrafish, thereby leading to recovery from severe liver damage.

ADDITIONAL INFORMATION