Dissection the Hepatitis B Virus Replication Mechanisms and Advances in In Vivo Models: A Comprehensive Review.

Chronic infection of the Hepatitis B virus (HBV) is a leading cause of advanced liver diseases. The process of HBV replication and available in-vivo models to study the HBV are very complex. The entry into hepatocytes is a multifaceted interplay involving viral particles, host cell receptors, and endocytic processes. Interaction between the HBV viral particle and specific host receptors such as sodium taurocholate co-transporting polypeptide (NTCP), epidermal growth factor receptor (EGFR), and asialoglycoprotein receptor (ASGPR) triggers internalization through clathrin-dependent endocytosis. Subsequently, the HBV genome is transported into the host cell nucleus through a series of steps including capsid disassembly, engagement of transport factors, chromatinization, ultimately resulting in the formation of covalently closed circular DNA (cccDNA). There are various animal models used to study HBV. A thorough understanding of these mechanisms and models is crucial for unravelling the HBV lifecycle and advancing the development of targeted therapeutic strategies. This review provides an in-depth analysis of HBV replication and highlights recent insights into various animal models used to study HBV.