[In situ hybridization study of HBV DNA in chronic active hepatitis]

Liver biopsies from 50 patients with chronic active hepatitis B were analysed immunohistochemically for HBcAg and HBsAg, and with in situ hybridization for HBV DNA. Double labelling technique for detecting HBV DNA and viral antigens simultaneously was also performed in some of these cases. The results showed that localization of HBV DNA in hepatocytes could be classified into whole cytoplasmic, submembranous, nucleic and intermembranous types. The last type suggests that HBV DNA might be transmitted directly to the adjacent hepatocytes through the cell membrane. By double labelling technique, it was disclosed that most hepatocytes with high level of HBV replication did not contain HBcAg or HBsAg. Conversely and most liver cells strongly positive for HBAg have low or negligible level of viral replication. Additionally, in a few cases, HBV DNA was found in the cytoplasm of bile ductule epithelia and sinusoidal endothelia.