Establishment and characterization of a diethylnitrosamine-initiated woodchuck hepatocyte cell line.

Woodchucks free from woodchuck hepatitis virus were treated with diethylnitrosamine in vivo for 2 months, and then hepatocytes obtained by enzymatic perfusion were cultured with the hepatopromoter phenobarbital. This in vivo-in vitro procedure gave rise to proliferating epithelial cell foci, from one of which the presently described hepatocyte cell line (WLC-3) was established and characterized. WLC-3 cells possess morphological and biochemical features of differentiated hepatocytes, including glucose-6-phosphatase activity and albumin production. Histopathological analysis of the tumor which developed transitorily in nude mouse subcutis after inoculation of the cell line revealed glandular structures comprising cells of hepatocellular-like morphology. This is the first established woodchuck hepatocyte cell line free from woodchuck hepatitis virus and is therefore expected to be useful for studying the mode of gene expression and viral proliferation of woodchuck hepatitis virus and the mechanisms underlying woodchuck hepatitis virus-related hepatocarcinogenesis.