Hepatitis B virus (HBV)-transgenic mice as an investigative tool to study immunopathology during HBV infection.

An overview is given regarding the use of hepatitis B virus (HBV) transgenic mice as an animal model of the HBV-carrier state. Initially, we show how HBV-transgenic mice have contributed insights into the immunopathobiological processes during HBV infection and later, we show how this new information from the experiments with HBV-transgenic mice could be used to develop new methods to combat HBV infection. By microinjecting the full or selected parts of the HBV-genome into the fertilized eggs of inbred mice, different laboratories have developed different lines of HBV-transgenic mice, which express products of the HBV genome and also show signs of HBV replication. Studies in HBV-transgenic mice have provided insights into the process of destruction of hepatocytes, the critical role of cytokines in controlling HBV replication and gene expression, mechanisms underlying the immune response defect in chronic HBV-carriers and the critical role of antigen presenting cells (APC), especially that of antigen presenting dendritic cells in persistent HBV infection. All this new information has given us a better understanding about HBV immunopathobiology, and has led to the development of new therapeutic approaches to combat HBV infection.