[Establishment of hepatitis B virus model animals by HVJ-liposome method]

Hepatitis B virus (HBV) surface antigen (HBsAg) genes were injected directly into liver of adult rodents by HVJ-liposome method in order to develop HBV model rodents. From immunohistochemical analysis, liver cells transfected with the HBsAg genes expressed the Ag in vivo. Transfection of plasmid expressing only small S antigen (secretory type) resulted in detection of HBsAg in sera of rats for 9 days. On successive injection of the HBsAg (large S, middle S, and small S) genes, the antibody to HBsAg was produced in the sera of rats. Furthermore, liver tissues in the rats showed infiltration of lymphocytes and hepatocytes degeneration in the parenchyma and inflammation of Glisson's sheaths histologically. The HVJ-liposome method may be suitable for evaluating a series of process from expression of viral components to induction of viral diseases in the living body.