HBV culture and infectious systems.

Area of Science:

• Hepatology
• Virology
• Infectious Diseases

Background:

• Chronic hepatitis B virus (HBV) infection is a major global health issue with limited treatment efficacy.
• Current therapies suppress HBV replication but rarely eliminate the virus, necessitating long-term treatment.
• Understanding HBV's complex life cycle, especially entry mechanisms, is hindered by a lack of suitable infection models.

Purpose of the Study:

• To review the challenges and advancements in developing hepatitis B virus (HBV) infection systems.
• To highlight the importance of liver-specific factors and suitable models for studying HBV entry.
• To identify potential avenues for novel drug targets and therapies for chronic HBV infection.

Main Methods:

• Review of current literature on HBV infection models, including cell lines and animal models.
• Discussion of the role of sodium taurocholate transporting peptide (NTCP) as an HBV receptor.
• Exploration of limitations and potential of primary hepatocytes, HepaRG, HepG2-NTCP, and chimeric mice models.

Main Results:

• Hepatoma cell lines like HepG2 do not support HBV replication, while HepaRG cells are permissive.
• The discovery of NTCP has enabled the creation of replication-competent HepG2-NTCP cell lines.
• Chimeric mice with human hepatocytes offer a viable model for HBV studies, overcoming limitations of primary cells.

Conclusions:

• Developing effective HBV infection systems remains a significant hurdle for advancing chronic hepatitis B treatments.
• Variability and limited efficiency in current cell line models suggest the involvement of additional, uncharacterized liver-specific factors.
• Further research into HBV infection mechanisms and improved models are essential for discovering novel therapeutic strategies and drug targets.