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Updated: Oct 16, 2025
Author Spotlight: Advancements and Challenges in Hepatitis B Virus Detection
Published on: December 15, 2023
Approaches to quantifying hepatitis B virus covalently closed circular DNA
Henrik Zhang1, Thomas Tu1,2
1Storr Liver Centre, Westmead Clinical School and Westmead Institute for Medical Research, Faculty of Medicine and Health, The University of Sydney, Westmead, Australia.
Insights
Quantifying hepatitis B virus (HBV) covalently closed circular DNA (cccDNA) is crucial for treating chronic hepatitis B. Current methods face challenges, hindering progress in developing cures for this persistent liver disease.
Area of Science:
- Hepatology
- Virology
- Molecular Biology
Background:
- Chronic hepatitis B is a significant global health issue and remains incurable.
- Hepatitis B virus (HBV) covalently closed circular DNA (cccDNA) drives viral persistence and is the template for viral RNA transcription.
- Accurate quantification of HBV cccDNA is essential for developing curative therapies.
Purpose of the Study:
- To review current methods for quantifying HBV cccDNA.
- To highlight the technical challenges in HBV cccDNA detection and quantification.
- To identify open questions in HBV cccDNA biology due to methodological limitations.
Main Methods:
- Review of existing literature on HBV cccDNA quantification assays.
- Discussion of direct and indirect detection methods for HBV cccDNA.
- Analysis of limitations associated with PCR and hybridization techniques.
Main Results:
- Various assays have been developed to overcome quantification challenges.
- Methods focus on direct detection or indirect measurement via transcriptional products.
- Technical hurdles include sequence homology, low copy numbers, and heat resistance.
Conclusions:
- Accurate quantification of HBV cccDNA is a persistent challenge in hepatitis B research.
- Limitations in current methods impede a full understanding of cccDNA biology.
- Further development of robust quantification techniques is needed to advance curative strategies for chronic hepatitis B.
Abstract:
Chronic hepatitis B is a major cause of liver disease worldwide and is currently incurable. Hepatitis B virus (HBV) covalently closed circular (ccc) DNA is a key form of the virus responsible for its persistence and is the transcriptional template for all viral transcripts. The field is focussed on methods to clear HBV cccDNA but this been limited by technical difficulties in its quantification due to: identical sequence to other forms of HBV DNA; low copy number per cell; and high resistance to denaturation by heat, leading to difficulty using polymerase chain reaction or hybridization methods for detection. A number of assays have been developed in order to overcome these hurdles either directly or detecting cccDNA levels indirectly via its transcriptional products. In this review, we summarize the approaches to cccDNA quantification that are currently used, and outline key open questions in the cccDNA biology field which remain to be answered due to the limitations of current methods.
