Detection of hepatitis B virus DNA in the liver of children with chronic hepatitis B by in situ hybridization and its relation to other viral markers.

The aim of the study was to detect hepatitis B virus (HBV) DNA by in situ hybridization (ISH) with a 35S-labeled radioactive probe in frozen liver biopsy tissue sections of 63 hepatitis B virus surface antigen (HBsAg)-positive children. The results were compared to other markers of viral replication. HBV DNA was detected in 48 children. Of the 15 negative cases, four had hepatitis B envelope antigen (HBeAg), 10 anti-HBe, and one neither HBeAg nor anti-HBe. Free HBV DNA in serum and liver was positive in one patient. Forty of the positive children were HBeAg- and six anti-HBe-positive; two were negative for both. Of 45 36 had HBV DNA in serum. In 38 of 47 HBV DNA and in 31 of 42 HBcAg could be detected in the liver. The HBV DNA signals were located mainly over the cytoplasm of hepatocytes. The distribution of HBV DNA in the tissue was classified as homogeneous, inhomogeneous with focal patches, and focal. It is concluded that in situ hybridization is a reliable method for detection of HBV DNA in liver tissue of children with chronic hepatitis B. The technique, which can be applied to small amounts of liver tissue, provides informations about the distribution of replicative viral sequences, complementing laboratory data, liver histochemistry, and histology.