Chronic infection in woodchucks infected by a cloned hepatitis delta virus.

Two woodchucks (Marmota monax) intrahepatically inoculated with hepatitis delta virus (HDV) complementary DNA clones pSVL-D3 and pSVL-Ag showed virological and pathological signs of acute and chronic HDV infection. HDV-RNA and hepatitis delta antigen (HDAg) were detected in serum by slot-blot hybridization and by western blot five weeks after inoculation. Liver biopsy specimens collected at 8th week post inoculum were positive for HDV-RNA. Anti-HDV antibodies were detected at the 11th and 9th weeks, respectively. Histological finding of hepatocarcinoma and persistence of circulating HDV-RNA and anti-HDV were observed up to the 10th month. Both woodchucks produced "small" and "large" HDAg antigen, although the inoculated cloned DNA bears the coding capability solely for the small antigen. A transient decrease of woodchuck hepatitis virus DNA (WHV-DNA) level was observed during the peak of HDV infection. Successive inoculation of acute-phase serum in three woodchucks resulted in a successful infection in one of the animals.