DECODING HEPATITIS B VIRUS: MOLECULAR INSIGHTS INTO VIRAL ARCHITECTURE, ENTRY PATHWAYS AND HOST DISEASE DYNAMICS.
Main Article Content
Keywords
Hepatitis B virus (HBV), Viral genome organization, HBV surface and core antigens, NTCP receptor-mediated entry, Covalently closed circular DNA (cccDNA), HBV replication cycle, Host-virus interactions, Chronic hepatitis B progression, Hepatic fibrosis and cirrhosis, HBV-induced hepatocellular carcinoma (HCC).
Abstract
Background: Hepatitis B virus remains a significant global health concern, particularly in endemic regions such as Asia and Africa. Despite the availability of effective vaccines and antiviral therapies, chronic HBV infection continues to cause substantial morbidity and mortality through liver cirrhosis and hepatocellular carcinoma.
Aim: This review aims to provide a comprehensive understanding of the molecular architecture of HBV, its mechanisms of host entry, viral replication, and the progression to chronic liver disease. By decoding these processes, the study highlights potential avenues for improved therapeutic strategies.
Methods: A detailed literature-based analysis was conducted using peer-reviewed articles, molecular virology reports, and clinical studies focusing on HBV structure, genome organization, protein function, viral entry pathways, and the dynamics of host-pathogen interactions. The review integrates molecular data with clinical outcomes to elucidate how viral and host factors shape disease progression.
Key Findings: HBV has a compact, partially double-stranded DNA genome encoding four overlapping open reading frames, each critical for replication and immune evasion. Entry into hepatocytes is mediated by the NTCP, with subsequent formation of cccDNA serving as the key template for viral persistence.
Conclusion: Understanding the molecular and cellular mechanisms underpinning HBV infection is essential for developing more effective antiviral strategies. While current therapies can suppress viral replication, they do not eliminate cccDNA or fully reverse immune dysfunction in chronic carriers. Comprehensive insights into the viral life cycle and host responses provide a foundation for future therapeutic innovations.
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Khushdeep Singh
Dept. of Biochemistry, Guru Gobind Singh Medical College & Hospital, Faridkot, Punjab, India.
Sahiba Kukreja
Dept. of Biochemistry, Sri Guru Ramdas Institute of health Sciences & Research, Sri Amritsar, Punjab, India
Rajinderjit Singh Ahi
Dept. of Biochemistry, Guru Gobind Singh Medical College & Hospital, Faridkot, Punjab, India.
Sumit Kumar
Dept. of Internal Medicine, Guru Gobind Singh Medical College & Hospital, Faridkot, Punjab, India.
Amandeep Singh Birdi
Dept. of Biochemistry, Guru Gobind Singh Medical College & Hospital, Faridkot, Punjab, India.
Kirti
Dept. of Biochemistry, Guru Gobind Singh Medical College & Hospital, Faridkot, Punjab, India.
Jaspreet Singh
Dept. of Biochemistry, Pandit Bhagwat Dayal Sharma University of Health Sciences, Rohtak, Haryana, India.