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1
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Burkard M, Piotrowsky A, Leischner C, Detert K, Venturelli S, Marongiu L. The Antiviral Activity of Polyphenols. Mol Nutr Food Res 2025:e70042. [PMID: 40166854 DOI: 10.1002/mnfr.70042] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2024] [Revised: 02/27/2025] [Accepted: 03/10/2025] [Indexed: 04/02/2025]
Abstract
Polyphenols are secondary metabolites produced by a large variety of plants. These compounds that comprise the class of phenolic acids, stilbenes, lignans, coumarins, flavonoids, and tannins have a wide range of employment, from food production to medical usages. Among the beneficial applications of polyphenols, their antiviral activity is gaining importance due to the increased prevalence of drug-resistant viruses such as herpes and hepatitis B viruses. In the present review, we provide an overview of the most promising or commonly used antiviral polyphenols and their mechanisms of action focusing on their effects on enveloped viruses of clinical importance (double-stranded linear or partially double-stranded circular DNA viruses, negative sense single-stranded RNA viruses with nonsegmented or segmented genomes, and positive sense single-stranded RNA viruses). The present work emphasizes the relevance of polyphenols, in particular epigallocatechin-3-gallate and resveratrol, as alternative or supportive antivirals. Polyphenols could interfere with virtually all steps of viral infection, from the adsorption to the release of viral particles. The activity of polyphenols against viruses is especially relevant given the risk of widespread outbreaks associated with viruses, remarked by the recent COVID-19 pandemic.
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Affiliation(s)
- Markus Burkard
- Department of Nutritional Biochemistry, University of Hohenheim, Stuttgart, Germany
| | - Alban Piotrowsky
- Department of Nutritional Biochemistry, University of Hohenheim, Stuttgart, Germany
| | - Christian Leischner
- Department of Nutritional Biochemistry, University of Hohenheim, Stuttgart, Germany
| | - Katja Detert
- Department of Nutritional Biochemistry, University of Hohenheim, Stuttgart, Germany
| | - Sascha Venturelli
- Department of Nutritional Biochemistry, University of Hohenheim, Stuttgart, Germany
- Department of Vegetative and Clinical Physiology, Institute of Physiology, University of Tuebingen, Tuebingen, Germany
| | - Luigi Marongiu
- Department of Nutritional Biochemistry, University of Hohenheim, Stuttgart, Germany
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2
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Jin Y, Wang S, Tang K, Zhan P, Liu X. Recent advances in screening methods enabling the discovery of novel anti-hepatitis B virus drug candidates. Eur J Med Chem 2025; 282:117093. [PMID: 39612566 DOI: 10.1016/j.ejmech.2024.117093] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2024] [Revised: 11/15/2024] [Accepted: 11/21/2024] [Indexed: 12/01/2024]
Abstract
The global population affected by Hepatitis B virus (HBV) is approximately 296 million, but few drugs have been able to completely eradicate HBV and the range of effective treatments remains limited. Recent advancements in molecular biology and artificial intelligence, as well as a comprehensive understanding of the molecular structure of HBV, have greatly aided the rational development of anti-HBV agents. Such advancements have facilitated an increasing array of candidate drugs transitioning into clinical trials, however, no novel target-based compounds have been approved for clinical application. To expedite the progression of anti-HBV drug development, establishing a reliable and robust in vitro HBV infection system is of great importance. However, owing to the host and tissue specificity of HBV, identifying a stable and dependable cell culture system for screening all anti-HBV agents poses significant challenges. In this review, we summarize recent advances in screening methods for small-molecule inhibitors that target key stages of the HBV replication cycle from a medicinal chemistry perspective.
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Affiliation(s)
- Yu Jin
- Department of Medicinal Chemistry, Key Laboratory of Chemical Biology (Ministry of Education), School of Pharmaceutical Sciences, Shandong University, 44 West Culture Road, 250012, Jinan, Shandong, PR China
| | - Shuo Wang
- Department of Medicinal Chemistry, Key Laboratory of Chemical Biology (Ministry of Education), School of Pharmaceutical Sciences, Shandong University, 44 West Culture Road, 250012, Jinan, Shandong, PR China
| | - Kai Tang
- Department of Medicinal Chemistry, Key Laboratory of Chemical Biology (Ministry of Education), School of Pharmaceutical Sciences, Shandong University, 44 West Culture Road, 250012, Jinan, Shandong, PR China
| | - Peng Zhan
- Department of Medicinal Chemistry, Key Laboratory of Chemical Biology (Ministry of Education), School of Pharmaceutical Sciences, Shandong University, 44 West Culture Road, 250012, Jinan, Shandong, PR China.
| | - Xinyong Liu
- Department of Medicinal Chemistry, Key Laboratory of Chemical Biology (Ministry of Education), School of Pharmaceutical Sciences, Shandong University, 44 West Culture Road, 250012, Jinan, Shandong, PR China.
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3
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Zhao K, Wang J, Wang Z, Wang M, Li C, Xu Z, Zhan Q, Guo F, Cheng X, Xia Y. Hepatitis B virus hijacks MRE11-RAD50-NBS1 complex to form its minichromosome. PLoS Pathog 2025; 21:e1012824. [PMID: 39752632 PMCID: PMC11734937 DOI: 10.1371/journal.ppat.1012824] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2024] [Revised: 01/15/2025] [Accepted: 12/13/2024] [Indexed: 01/16/2025] Open
Abstract
Chronic hepatitis B virus (HBV) infection can significantly increase the incidence of cirrhosis and liver cancer, and there is no curative treatment. The persistence of HBV covalently closed circular DNA (cccDNA) is the major obstacle of antiviral treatments. cccDNA is formed through repairing viral partially double-stranded relaxed circular DNA (rcDNA) by varies host factors. However, the detailed mechanisms are not well characterized. To dissect the biogenesis of cccDNA, we took advantage of an in vitro rcDNA repair system to precipitate host factors interacting with rcDNA and identified co-precipitated proteins by mass spectrometry. Results revealed the MRE11-RAD50-NBS1 (MRN) complex as a potential factor. Transiently or stably knockdown of MRE11, RAD50 or NBS1 in hepatocytes before HBV infection significantly decreased viral markers, including cccDNA, while reconstitution reversed the effect. Chromatin immunoprecipitation assay further validated the interaction of MRN complex and HBV DNA. However, MRN knockdown after HBV infection showed no effect on viral replication, which indicated that MRN complex inhibited the formation of cccDNA without affecting its stability or transcriptional activity. Interestingly, Mirin, a MRN complex inhibitor which can inhibit the exonuclease activity of MRE11 and MRN-dependent activation of ATM, but not ATM kinase inhibitor KU55933, could decrease cccDNA level. Likewise, the MRE11 endonuclease activity inhibitor PFM01 treatment decreased cccDNA. MRE11 nuclease assays indicated that rcDNA is a substrate of MRE11. Furthermore, the inhibition of ATR-CHK1 pathway, which is known to be involved in cccDNA formation, impaired the effect of MRN complex on cccDNA. Similarly, inhibition of MRE11 endonuclease activity mitigated the effect of ATR-CHK1 pathway on cccDNA. These findings indicate that MRN complex cooperates with ATR-CHK1 pathway to regulate the formation of HBV cccDNA. In summary, we identified host factors, specifically the MRN complex, regulating cccDNA formation during HBV infection. These findings provide insights into how HBV hijacks host enzymes to establish chronic infection and reveal new therapeutic opportunities.
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Affiliation(s)
- Kaitao Zhao
- State Key Laboratory of Virology and Biosafety and Hubei Province Key Laboratory of Allergy and Immunology, Institute of Medical Virology, TaiKang Medical School, Wuhan University, Wuhan, China
| | - Jingjing Wang
- State Key Laboratory of Virology and Biosafety and Hubei Province Key Laboratory of Allergy and Immunology, Institute of Medical Virology, TaiKang Medical School, Wuhan University, Wuhan, China
| | - Zichen Wang
- State Key Laboratory of Virology and Biosafety and Hubei Province Key Laboratory of Allergy and Immunology, Institute of Medical Virology, TaiKang Medical School, Wuhan University, Wuhan, China
| | - Mengfei Wang
- State Key Laboratory of Virology and Biosafety and Hubei Province Key Laboratory of Allergy and Immunology, Institute of Medical Virology, TaiKang Medical School, Wuhan University, Wuhan, China
| | - Chen Li
- State Key Laboratory of Virology and Biosafety and Hubei Province Key Laboratory of Allergy and Immunology, Institute of Medical Virology, TaiKang Medical School, Wuhan University, Wuhan, China
| | - Zaichao Xu
- State Key Laboratory of Virology and Biosafety and Hubei Province Key Laboratory of Allergy and Immunology, Institute of Medical Virology, TaiKang Medical School, Wuhan University, Wuhan, China
| | - Qiong Zhan
- State Key Laboratory of Virology and Biosafety and Hubei Province Key Laboratory of Allergy and Immunology, Institute of Medical Virology, TaiKang Medical School, Wuhan University, Wuhan, China
| | - Fangteng Guo
- State Key Laboratory of Virology and Biosafety and Hubei Province Key Laboratory of Allergy and Immunology, Institute of Medical Virology, TaiKang Medical School, Wuhan University, Wuhan, China
| | - Xiaoming Cheng
- State Key Laboratory of Virology and Biosafety and Hubei Province Key Laboratory of Allergy and Immunology, Institute of Medical Virology, TaiKang Medical School, Wuhan University, Wuhan, China
- Wuhan University Center for Pathology and Molecular Diagnostics, Zhongnan Hospital of Wuhan University, Wuhan, China
- Hubei Clinical Center and Key Laboratory of Intestinal and Colorectal Diseases, Wuhan, China
| | - Yuchen Xia
- State Key Laboratory of Virology and Biosafety and Hubei Province Key Laboratory of Allergy and Immunology, Institute of Medical Virology, TaiKang Medical School, Wuhan University, Wuhan, China
- Hubei Jiangxia Laboratory, Wuhan, China
- Pingyuan Laboratory, Henan, China
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4
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Ren J, Cheng S, Ren F, Gu H, Wu D, Yao X, Tan M, Huang A, Chen J. Epigenetic regulation and its therapeutic potential in hepatitis B virus covalently closed circular DNA. Genes Dis 2025; 12:101215. [PMID: 39534573 PMCID: PMC11555349 DOI: 10.1016/j.gendis.2024.101215] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2023] [Revised: 11/25/2023] [Accepted: 12/05/2023] [Indexed: 11/16/2024] Open
Abstract
Human hepatitis B virus (HBV) infection is the major cause of acute and chronic hepatitis B, liver cirrhosis, and hepatocellular carcinoma. Although the application of prophylactic vaccination programs has successfully prevented the trend of increasing HBV infection prevalence, the number of HBV-infected people remains very high. Approved therapeutic management efficiently suppresses viral replication; however, HBV infection is rarely completely resolved. The major reason for therapeutic failure is the persistence of covalently closed circular DNA (cccDNA), which forms viral minichromosomes by combining with histone and nonhistone proteins in the nucleus. Increasing evidence indicates that chromatin-modifying enzymes, viral proteins, and noncoding RNAs are essential for modulating the function of cccDNA. Therefore, a deeper understanding of the regulatory mechanism underlying cccDNA transcription will contribute to the development of a cure for chronic hepatitis B. This review summarizes the current knowledge of cccDNA biology, the regulatory mechanisms underlying cccDNA transcription, and novel anti-HBV approaches for eliminating cccDNA transcription.
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Affiliation(s)
- Jihua Ren
- The Key Laboratory of Molecular Biology of Infectious Diseases Designated by the Chinese Ministry of Education, Chongqing Medical University, Chongqing 400000, China
| | - Shengtao Cheng
- The Key Laboratory of Molecular Biology of Infectious Diseases Designated by the Chinese Ministry of Education, Chongqing Medical University, Chongqing 400000, China
| | - Fang Ren
- Chongqing Key Laboratory of Sichuan-Chongqing Co-construction for Diagnosis and Treatment of Infectious Diseases Integrated Traditional Chinese and Western Medicine, Chongqing Hospital of Traditional Chinese Medicine, Chongqing 400000, China
| | - Huiying Gu
- The Key Laboratory of Molecular Biology of Infectious Diseases Designated by the Chinese Ministry of Education, Chongqing Medical University, Chongqing 400000, China
| | - Daiqing Wu
- The Key Laboratory of Molecular Biology of Infectious Diseases Designated by the Chinese Ministry of Education, Chongqing Medical University, Chongqing 400000, China
| | - Xinyan Yao
- The Key Laboratory of Molecular Biology of Infectious Diseases Designated by the Chinese Ministry of Education, Chongqing Medical University, Chongqing 400000, China
| | - Ming Tan
- The Key Laboratory of Molecular Biology of Infectious Diseases Designated by the Chinese Ministry of Education, Chongqing Medical University, Chongqing 400000, China
| | - Ailong Huang
- The Key Laboratory of Molecular Biology of Infectious Diseases Designated by the Chinese Ministry of Education, Chongqing Medical University, Chongqing 400000, China
| | - Juan Chen
- The Key Laboratory of Molecular Biology of Infectious Diseases Designated by the Chinese Ministry of Education, Chongqing Medical University, Chongqing 400000, China
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5
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He W, Zheng Z, Zhao Q, Zhang R, Zheng H. Targeting HBV cccDNA Levels: Key to Achieving Complete Cure of Chronic Hepatitis B. Pathogens 2024; 13:1100. [PMID: 39770359 PMCID: PMC11728772 DOI: 10.3390/pathogens13121100] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2024] [Revised: 12/07/2024] [Accepted: 12/11/2024] [Indexed: 01/16/2025] Open
Abstract
Chronic hepatitis B (CHB) caused by HBV infection has brought suffering to numerous people. Due to the stable existence of HBV cccDNA, the original template for HBV replication, chronic hepatitis B (CHB) is difficult to cure completely. Despite current antiviral strategies being able to effectively limit the progression of CHB, complete CHB cure requires directly targeting HBV cccDNA. In this review, we discuss strategies that may achieve a complete cure of CHB, including inhibition of cccDNA de novo synthesis, targeting cccDNA degradation through host factors and small molecules, CRISP-Cas9-based cccDNA editing, and silencing cccDNA epigenetically.
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Affiliation(s)
- Wei He
- Jiangsu Key Laboratory of Infection and Immunity, Institutes of Biology and Medical Sciences, Soochow University, Suzhou 215123, Jiangsu, China; (W.H.); (Z.Z.)
- MOE Key Laboratory of Geriatric Disease and Immunology of Ministry of Education of China, Collaborative Innovation Center of Hematology, International Institute of Infection and Immunity, Institutes of Biology and Medical Sciences (IBMS), School of Medicine, Soochow University, Suzhou 215123, Jiangsu, China
| | - Zhijin Zheng
- Jiangsu Key Laboratory of Infection and Immunity, Institutes of Biology and Medical Sciences, Soochow University, Suzhou 215123, Jiangsu, China; (W.H.); (Z.Z.)
- MOE Key Laboratory of Geriatric Disease and Immunology of Ministry of Education of China, Collaborative Innovation Center of Hematology, International Institute of Infection and Immunity, Institutes of Biology and Medical Sciences (IBMS), School of Medicine, Soochow University, Suzhou 215123, Jiangsu, China
| | - Qian Zhao
- Jiangsu Key Laboratory of Infection and Immunity, Institutes of Biology and Medical Sciences, Soochow University, Suzhou 215123, Jiangsu, China; (W.H.); (Z.Z.)
- MOE Key Laboratory of Geriatric Disease and Immunology of Ministry of Education of China, Collaborative Innovation Center of Hematology, International Institute of Infection and Immunity, Institutes of Biology and Medical Sciences (IBMS), School of Medicine, Soochow University, Suzhou 215123, Jiangsu, China
| | - Renxia Zhang
- Jiangsu Key Laboratory of Infection and Immunity, Institutes of Biology and Medical Sciences, Soochow University, Suzhou 215123, Jiangsu, China; (W.H.); (Z.Z.)
- MOE Key Laboratory of Geriatric Disease and Immunology of Ministry of Education of China, Collaborative Innovation Center of Hematology, International Institute of Infection and Immunity, Institutes of Biology and Medical Sciences (IBMS), School of Medicine, Soochow University, Suzhou 215123, Jiangsu, China
| | - Hui Zheng
- Jiangsu Key Laboratory of Infection and Immunity, Institutes of Biology and Medical Sciences, Soochow University, Suzhou 215123, Jiangsu, China; (W.H.); (Z.Z.)
- MOE Key Laboratory of Geriatric Disease and Immunology of Ministry of Education of China, Collaborative Innovation Center of Hematology, International Institute of Infection and Immunity, Institutes of Biology and Medical Sciences (IBMS), School of Medicine, Soochow University, Suzhou 215123, Jiangsu, China
- Department of Laboratory Medicine, Institute of Laboratory Medicine, Sichuan Provincial People’s Hospital, School of Medicine, University of Electronic Science and Technology of China, Chengdu 611731, Sichuan, China
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6
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Lei Z, Wang L, Gao H, Guo S, Kang X, Yuan J, Lv Z, Jiang Y, Yi J, Chen Z, Wang G. Mechanisms underlying the compromised clinical efficacy of interferon in clearing HBV. Virol J 2024; 21:314. [PMID: 39633459 PMCID: PMC11619119 DOI: 10.1186/s12985-024-02589-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2024] [Accepted: 11/26/2024] [Indexed: 12/07/2024] Open
Abstract
Hepatitis B virus (HBV) is a hepatotropic DNA virus that can cause acute or chronic hepatitis, representing a significant global health concern. By 2019, approximately 296 million individuals were chronically infected with HBV, with 1.5 million new cases annually and 820,000 deaths due to HBV-related cirrhosis and liver cancer. Current treatments for chronic hepatitis B include nucleotide analogs (NAs) and interferons (IFNs), particularly IFN-α. NAs, such as entecavir and tenofovir, inhibit viral reverse transcription, while IFN-α exerts antiviral effects by directly suppressing viral replication, modulating viral genome epigenetics, degrading cccDNA, and activating immune responses. Despite its potential, IFN-α shows limited clinical efficacy, partly due to HBV's interference with the IFN signaling pathway. HBV encodes proteins like HBc, Pol, HBsAg, and HBx that disrupt IFN-α function. For example, HBV Pol inhibits STAT1 phosphorylation, HBsAg suppresses STAT3 phosphorylation, and HBx interferes with IFN-α efficacy through multiple mechanisms. Additionally, HBV downregulates key genes in the IFN signaling pathway, further diminishing IFN-α's antiviral effects. Understanding these interactions is crucial for improving IFN-α-based therapies. Future research may focus on overcoming HBV resistance by targeting viral proteins or optimizing IFN-α delivery. In summary, HBV's ability to resist IFN-α limits its therapeutic effectiveness, highlighting the need for new strategies to enhance treatment outcomes.
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Affiliation(s)
- Zhuoyan Lei
- Key Laboratory of Artificial Organs and Computational Medicine of Zhejiang Province, Shulan International Medical College, Zhejiang Shuren University, 8 Shuren St, Gongshu District, Hangzhou, 310015, Zhejiang Province, China
| | - Luye Wang
- Key Laboratory of Artificial Organs and Computational Medicine of Zhejiang Province, Shulan International Medical College, Zhejiang Shuren University, 8 Shuren St, Gongshu District, Hangzhou, 310015, Zhejiang Province, China
| | - Hanlin Gao
- Key Laboratory of Artificial Organs and Computational Medicine of Zhejiang Province, Shulan International Medical College, Zhejiang Shuren University, 8 Shuren St, Gongshu District, Hangzhou, 310015, Zhejiang Province, China
| | - Shubian Guo
- Key Laboratory of Artificial Organs and Computational Medicine of Zhejiang Province, Shulan International Medical College, Zhejiang Shuren University, 8 Shuren St, Gongshu District, Hangzhou, 310015, Zhejiang Province, China
| | - Xinjian Kang
- Key Laboratory of Artificial Organs and Computational Medicine of Zhejiang Province, Shulan International Medical College, Zhejiang Shuren University, 8 Shuren St, Gongshu District, Hangzhou, 310015, Zhejiang Province, China
| | - Jiajun Yuan
- Key Laboratory of Artificial Organs and Computational Medicine of Zhejiang Province, Shulan International Medical College, Zhejiang Shuren University, 8 Shuren St, Gongshu District, Hangzhou, 310015, Zhejiang Province, China
| | - Ziying Lv
- Key Laboratory of Artificial Organs and Computational Medicine of Zhejiang Province, Shulan International Medical College, Zhejiang Shuren University, 8 Shuren St, Gongshu District, Hangzhou, 310015, Zhejiang Province, China
| | - Yuxin Jiang
- Key Laboratory of Artificial Organs and Computational Medicine of Zhejiang Province, Shulan International Medical College, Zhejiang Shuren University, 8 Shuren St, Gongshu District, Hangzhou, 310015, Zhejiang Province, China
| | - Jinping Yi
- Department of Clinical Laboratory, the First Affiliated Hospital of Nanchang University, Nanchang, Jiangxi, China
| | - Zhi Chen
- State Key Laboratory for Diagnosis and Treatment of Infectious Diseases, Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, The First Affiliated Hospital, College of Medicine, National Clinical Research Center for Infectious Diseases, Zhejiang University, Hangzhou, China
| | - Gang Wang
- Key Laboratory of Artificial Organs and Computational Medicine of Zhejiang Province, Shulan International Medical College, Zhejiang Shuren University, 8 Shuren St, Gongshu District, Hangzhou, 310015, Zhejiang Province, China.
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Zhang M, Chen H, Liu H, Tang H. The impact of integrated hepatitis B virus DNA on oncogenesis and antiviral therapy. Biomark Res 2024; 12:84. [PMID: 39148134 PMCID: PMC11328401 DOI: 10.1186/s40364-024-00611-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2024] [Accepted: 06/29/2024] [Indexed: 08/17/2024] Open
Abstract
The global burden of hepatitis B virus (HBV) infection remains high, with chronic hepatitis B (CHB) patients facing a significantly increased risk of developing cirrhosis and hepatocellular carcinoma (HCC). The ultimate objective of antiviral therapy is to achieve a sterilizing cure for HBV. This necessitates the elimination of intrahepatic covalently closed circular DNA (cccDNA) and the complete eradication of integrated HBV DNA. This review aims to summarize the oncogenetic role of HBV integration and the significance of clearing HBV integration in sterilizing cure. It specifically focuses on the molecular mechanisms through which HBV integration leads to HCC, including modulation of the expression of proto-oncogenes and tumor suppressor genes, induction of chromosomal instability, and expression of truncated mutant HBV proteins. The review also highlights the impact of antiviral therapy in reducing HBV integration and preventing HBV-related HCC. Additionally, the review offers insights into future objectives for the treatment of CHB. Current strategies for HBV DNA integration inhibition and elimination include mainly antiviral therapies, RNA interference and gene editing technologies. Overall, HBV integration deserves further investigation and can potentially serve as a biomarker for CHB and HBV-related HCC.
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Affiliation(s)
- Mingming Zhang
- Center of Infectious Diseases, West China Hospital of Sichuan University, Chengdu, 610041, China
- Laboratory of Infectious and Liver Diseases, Institute of Infectious Diseases, West China Hospital of Sichuan University, Chengdu, 610041, China
| | - Han Chen
- Center of Infectious Diseases, West China Hospital of Sichuan University, Chengdu, 610041, China
- Laboratory of Infectious and Liver Diseases, Institute of Infectious Diseases, West China Hospital of Sichuan University, Chengdu, 610041, China
| | - Huan Liu
- Center of Infectious Diseases, West China Hospital of Sichuan University, Chengdu, 610041, China
- Laboratory of Infectious and Liver Diseases, Institute of Infectious Diseases, West China Hospital of Sichuan University, Chengdu, 610041, China
| | - Hong Tang
- Center of Infectious Diseases, West China Hospital of Sichuan University, Chengdu, 610041, China.
- Laboratory of Infectious and Liver Diseases, Institute of Infectious Diseases, West China Hospital of Sichuan University, Chengdu, 610041, China.
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8
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Gomez-Moreno A, Guo J, Temple HM, Ploss A. Formation and transcriptional regulation of hepatitis B virus covalently closed circular DNA. J Hepatol 2024; 81:367-369. [PMID: 38782610 DOI: 10.1016/j.jhep.2024.03.008] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/15/2023] [Revised: 03/07/2024] [Accepted: 03/08/2024] [Indexed: 05/25/2024]
Affiliation(s)
- Andoni Gomez-Moreno
- Department of Molecular Biology, Princeton University, Princeton, NJ 08544, United States of America
| | - Jinchao Guo
- Department of Molecular Biology, Princeton University, Princeton, NJ 08544, United States of America
| | - Heidi M Temple
- Department of Molecular Biology, Princeton University, Princeton, NJ 08544, United States of America
| | - Alexander Ploss
- Department of Molecular Biology, Princeton University, Princeton, NJ 08544, United States of America.
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9
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Tyagi P, Singh A, Kumar J, Ahmad B, Bahuguna A, Vivekanandan P, Sarin SK, Kumar V. Furanocoumarins promote proteasomal degradation of viral HBx protein and down-regulate cccDNA transcription and replication of hepatitis B virus. Virology 2024; 595:110065. [PMID: 38569227 DOI: 10.1016/j.virol.2024.110065] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2023] [Revised: 03/08/2024] [Accepted: 03/18/2024] [Indexed: 04/05/2024]
Abstract
Nucleot(s)ide analogues, the current antiviral treatments against chronic hepatitis B (CHB) infection, are non-curative due to their inability to eliminate covalently closed circular DNA (cccDNA) from the infected hepatocytes. Preclinical studies have shown that coumarin derivatives can effectively reduce the HBV DNA replication. We evaluated the antiviral efficacy of thirty new coumarin derivatives in cell culture models for studying HBV. Furanocoumarins Fc-20 and Fc-31 suppressed the levels of pre-genomic RNA as well as cccDNA, and reduced the secretion of virions, HBsAg and HBeAg. The antiviral efficacies of Fc-20 and Fc31 improved further when used in combination with the hepatitis B antiviral drug Entecavir. There was a marked reduction in the intracellular HBx level in the presence of these furanocoumarins due to proteasomal degradation resulting in the down-regulation of HBx-dependent viral genes. Importantly, both Fc-20 and Fc-31 were non-cytotoxic to cells even at high concentrations. Further, our molecular docking studies confirmed a moderate to high affinity interaction between furanocoumarins and viral HBx via residues Ala3, Arg26 and Lys140. These data suggest that furanocoumarins could be developed as a new therapeutic for CHB infection.
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Affiliation(s)
- Purnima Tyagi
- Department of Molecular and Cellular Medicine, Institute of Liver and Biliary Sciences, New Delhi, India
| | - Ankita Singh
- Department of Molecular and Cellular Medicine, Institute of Liver and Biliary Sciences, New Delhi, India
| | - Jitendra Kumar
- Department of Molecular and Cellular Medicine, Institute of Liver and Biliary Sciences, New Delhi, India
| | - Belal Ahmad
- Kusuma School of Biological Sciences, Indian Institute of Technology Delhi, New Delhi, India
| | - Aparna Bahuguna
- Elsevier/ RELX India Pvt Ltd., DLF Cyber City, Gurgaon, 122002, India
| | - Perumal Vivekanandan
- Kusuma School of Biological Sciences, Indian Institute of Technology Delhi, New Delhi, India
| | - Shiv Kumar Sarin
- Department of Hepatology, Institute of Liver and Biliary Sciences, New Delhi, India
| | - Vijay Kumar
- Department of Molecular and Cellular Medicine, Institute of Liver and Biliary Sciences, New Delhi, India.
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10
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Yip RPH, Kwok DCY, Lai LTF, Ho SM, Wong ICK, Chan CP, Lau WCY, Ngo JCK. SRPK2 Mediates HBV Core Protein Phosphorylation and Capsid Assembly via Docking Interaction. PLoS Pathog 2024; 20:e1011978. [PMID: 38324561 PMCID: PMC10878513 DOI: 10.1371/journal.ppat.1011978] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2022] [Revised: 02/20/2024] [Accepted: 01/17/2024] [Indexed: 02/09/2024] Open
Abstract
Members of the serine-arginine protein kinase (SRPK) family, SRPK1 and SRPK2, phosphorylate the hepatitis B core protein (Cp) and are crucial for pregenomic RNA encapsidation during viral nucleocapsid assembly. Among them, SRPK2 exhibits higher kinase activity toward Cp. In this study, we identified Cp sites that are phosphorylated by SRPK2 and demonstrated that the kinase utilizes an SRPK-specific docking groove to interact with and regulate the phosphorylation of the C-terminal arginine rich domain of Cp. We determined that direct interaction between the docking groove of SRPK2 and unphosphorylated Cp inhibited premature viral capsid assembly in vitro, whereas the phosphorylation of the viral protein reactivated the process. Pull-down assays together with the new cryo-electron microscopy structure of the HBV capsid in complex with SRPK2 revealed that the kinases decorate the surface of the viral capsid by interacting with the C-terminal domain of Cp, underscoring the importance of the docking interaction in regulating capsid assembly and pregenome packaging. Moreover, SRPK2-knockout in HepG2 cells suppressed Cp phosphorylation, indicating that SRPK2 is an important cellular kinase for HBV life cycle.
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Affiliation(s)
- Ryan Pak Hong Yip
- School of Life Sciences, The Chinese University of Hong Kong, Shatin, N.T., Hong Kong SAR, China
| | - Doris Ching Ying Kwok
- School of Life Sciences, The Chinese University of Hong Kong, Shatin, N.T., Hong Kong SAR, China
| | - Louis Tung Faat Lai
- School of Life Sciences, The Chinese University of Hong Kong, Shatin, N.T., Hong Kong SAR, China
| | - Siu-Ming Ho
- School of Biomedical Sciences, The University of Hong Kong, Pokfulam, Hong Kong, Hong Kong SAR, China
- State Key Laboratory of Liver Research (The University of Hong Kong), Pokfulam, Hong Kong, Hong Kong SAR, China
| | - Ivan Chun Kit Wong
- School of Life Sciences, The Chinese University of Hong Kong, Shatin, N.T., Hong Kong SAR, China
| | - Chi-Ping Chan
- School of Biomedical Sciences, The University of Hong Kong, Pokfulam, Hong Kong, Hong Kong SAR, China
- State Key Laboratory of Liver Research (The University of Hong Kong), Pokfulam, Hong Kong, Hong Kong SAR, China
| | - Wilson Chun Yu Lau
- School of Life Sciences, The Chinese University of Hong Kong, Shatin, N.T., Hong Kong SAR, China
- Center for Soybean Research of the State Key Laboratory of Agrobiotechnology, The Chinese University of Hong Kong, Shatin N.T., Hong Kong SAR, China
| | - Jacky Chi Ki Ngo
- School of Life Sciences, The Chinese University of Hong Kong, Shatin, N.T., Hong Kong SAR, China
- Center for Soybean Research of the State Key Laboratory of Agrobiotechnology, The Chinese University of Hong Kong, Shatin N.T., Hong Kong SAR, China
- Center for Novel Biomaterials, The Chinese University of Hong Kong, Shatin N.T., Hong Kong SAR, China
- Center for Protein Science and Crystallography, The Chinese University of Hong Kong, Shatin N.T., Hong Kong SAR, China
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11
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Hong X, Mendenhall MA, Hu J. Detection of Hepatitis B Virus Covalently Closed Circular DNA and Intermediates in Its Formation. Methods Mol Biol 2024; 2837:99-111. [PMID: 39044078 DOI: 10.1007/978-1-0716-4027-2_9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/25/2024]
Abstract
Hepatitis B virus (HBV) infection remains a global public health issue, and approximately 294 million individuals worldwide are chronically infected with HBV. Approved antivirals rarely cure chronic HBV infection due to their inability to eliminate the HBV covalently closed circular DNA (cccDNA), the viral episome, in the nucleus of infected hepatocytes. The persistence of cccDNA underlies the chronic nature of HBV infection and the frequent relapse after the cessation of antiviral treatment. However, drug development targeting cccDNA formation and maintenance is hindered by the lack of sufficient biological knowledge on cccDNA, and of its reliable detection due to its low abundance and the presence of high levels of HBV DNA species similar to cccDNA. Here, we describe a Southern blot method for reliably detecting the HBV cccDNA even in the presence of high levels of plasmid DNA and other HBV DNA species, based on the efficient removal of plasmid DNA and all DNA species with free 3' ends. This approach also allows the detection of certain potential intermediates during cccDNA formation.
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Affiliation(s)
- Xupeng Hong
- Department of Microbiology and Immunology, The Pennsylvania State University College of Medicine, Hershey, PA, USA
| | - Megan A Mendenhall
- Department of Microbiology and Immunology, The Pennsylvania State University College of Medicine, Hershey, PA, USA
| | - Jianming Hu
- Department of Microbiology and Immunology, The Pennsylvania State University College of Medicine, Hershey, PA, USA.
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12
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Abdul Majeed N, Zehnder B, Koh C, Heller T, Urban S. Hepatitis delta: Epidemiology to recent advances in therapeutic agents. Hepatology 2023; 78:1306-1321. [PMID: 36738087 DOI: 10.1097/hep.0000000000000331] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/02/2022] [Accepted: 12/19/2022] [Indexed: 02/05/2023]
Abstract
Hepatitis D virus (HDV) was first described in 1977 and is dependent on the presence of hepatitis B surface antigen (HBsAg) for its entry into cells and on the human host for replication. Due to the envelopment with the hepatitis B virus (HBV) envelope, early phases of HDV entry resemble HBV infection. Unlike HBV, HDV activates innate immune responses. The global prevalence of HDV is estimated to be about 5% of HBsAg positive individuals. However, recent studies have described a wide range of prevalence between 12 to 72 million individuals. Infection can occur as super-infection or co-infection. The diagnosis of active HDV infection involves screening with anti HDV antibodies followed by quantitative PCR testing for HDV RNA in those who are HBsAg positive. The diagnostic studies have evolved over the years improving the validity and reliability of the tests performed. HDV infection is considered the most severe form of viral hepatitis and the HDV genotype may influence the disease course. There are eight major HDV genotypes with prevalence varying by geographic region. HDV treatment has been challenging as HDV strongly depends on the host cell for replication and provides few, if any viral targets. Better understanding of HDV virology has led to the development of several therapeutic agents currently being studied in different phase II and III clinical trials. There is increasing promise of effective therapies that will ameliorate the course of this devastating disease.
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Affiliation(s)
- Nehna Abdul Majeed
- Liver Diseases Branch, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, Maryland, USA
| | - Benno Zehnder
- Department of Infectious Diseases, Molecular Virology, University Hospital Heidelberg, Heidelberg, Germany
| | - Christopher Koh
- Liver Diseases Branch, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, Maryland, USA
| | - Theo Heller
- Liver Diseases Branch, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, Maryland, USA
| | - Stephan Urban
- Department of Infectious Diseases, Molecular Virology, University Hospital Heidelberg, Heidelberg, Germany
- German Center for Infection Research (DZIF) - Heidelberg Partner Site, Heidelberg, Germany
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13
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Ranga A, Gupta A, Yadav L, Kumar S, Jain P. Advancing beyond reverse transcriptase inhibitors: The new era of hepatitis B polymerase inhibitors. Eur J Med Chem 2023; 257:115455. [PMID: 37216809 DOI: 10.1016/j.ejmech.2023.115455] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2023] [Revised: 05/03/2023] [Accepted: 05/03/2023] [Indexed: 05/24/2023]
Abstract
Hepatitis B virus (HBV) is a genetically diverse blood-borne virus responsible for chronic hepatitis B. The HBV polymerase plays a key role in viral genome replication within the human body and has been identified as a potential drug target for chronic hepatitis B therapeutics. However, available nucleotide reverse transcriptase inhibitors only target the reverse transcriptase domain of the HBV polymerase; they also pose resistance issues and require lifelong treatment that can burden patients financially. In this study, various chemical classes are reviewed that have been developed to target different domains of the HBV polymerase: Terminal protein, which plays a vital role in the formation of the viral DNA; Reverse transcriptase, which is responsible for the synthesis of the viral DNA from RNA, and; Ribonuclease H, which is responsible for degrading the RNA strand in the RNA-DNA duplex formed during the reverse transcription process. Host factors that interact with the HBV polymerase to achieve HBV replication are also reviewed; these host factors can be targeted by inhibitors to indirectly inhibit polymerase functionality. A detailed analysis of the scope and limitations of these inhibitors from a medicinal chemistry perspective is provided. The structure-activity relationship of these inhibitors and the factors that may affect their potency and selectivity are also examined. This analysis will be useful in supporting the further development of these inhibitors and in designing new inhibitors that can inhibit HBV replication more efficiently.
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Affiliation(s)
- Abhishek Ranga
- Department of Pharmacology, Delhi Institute of Pharmaceutical Sciences and Research, Delhi Pharmaceutical Sciences and Research University, Pushp Vihar, MB Road, New Delhi, 110017, India
| | - Aarti Gupta
- Department of Pharmaceutical Biotechnology, Delhi Pharmaceutical Sciences and Research University, Pushp Vihar, MB Road, New Delhi, 110017, India
| | - Laxmi Yadav
- Department of Pharmacology, Delhi Institute of Pharmaceutical Sciences and Research, Delhi Pharmaceutical Sciences and Research University, Pushp Vihar, MB Road, New Delhi, 110017, India
| | - Sachin Kumar
- Department of Pharmacology, Delhi Institute of Pharmaceutical Sciences and Research, Delhi Pharmaceutical Sciences and Research University, Pushp Vihar, MB Road, New Delhi, 110017, India.
| | - Priti Jain
- Department of Pharmaceutical Chemistry, Delhi Pharmaceutical Sciences and Research University, Pushp Vihar, MB Road, New Delhi, 110017, India.
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14
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Nevola R, Beccia D, Rosato V, Ruocco R, Mastrocinque D, Villani A, Perillo P, Imbriani S, Delle Femine A, Criscuolo L, Alfano M, La Montagna M, Russo A, Marfella R, Cozzolino D, Sasso FC, Rinaldi L, Marrone A, Adinolfi LE, Claar E. HBV Infection and Host Interactions: The Role in Viral Persistence and Oncogenesis. Int J Mol Sci 2023; 24:7651. [PMID: 37108816 PMCID: PMC10145402 DOI: 10.3390/ijms24087651] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2023] [Revised: 04/14/2023] [Accepted: 04/19/2023] [Indexed: 04/29/2023] Open
Abstract
Hepatitis B virus (HBV) is a major cause of chronic hepatitis, liver cirrhosis, and hepatocellular carcinoma. Despite the advent of vaccines and potent antiviral agents able to suppress viral replication, recovery from chronic HBV infection is still an extremely difficult goal to achieve. Complex interactions between virus and host are responsible for HBV persistence and the risk of oncogenesis. Through multiple pathways, HBV is able to silence both innate and adaptive immunological responses and become out of control. Furthermore, the integration of the viral genome into that of the host and the production of covalently closed circular DNA (cccDNA) represent reservoirs of viral persistence and account for the difficult eradication of the infection. An adequate knowledge of the virus-host interaction mechanisms responsible for viral persistence and the risk of hepatocarcinogenesis is necessary for the development of functional cures for chronic HBV infection. The purpose of this review is, therefore, to analyze how interactions between HBV and host concur in the mechanisms of infection, persistence, and oncogenesis and what are the implications and the therapeutic perspectives that follow.
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Affiliation(s)
- Riccardo Nevola
- Liver Unit, Ospedale Evangelico Betania, 80147 Naples, Italy; (V.R.); (D.M.); (P.P.); (E.C.)
- Department of Advanced Medical and Surgical Sciences, University of Campania “Luigi Vanvitelli”, 80138 Naples, Italy; (D.B.); (R.R.); (A.V.); (S.I.); (A.D.F.); (L.C.); (M.A.); (M.L.M.); (R.M.); (D.C.); (F.C.S.); (L.R.); (A.M.); (L.E.A.)
| | - Domenico Beccia
- Department of Advanced Medical and Surgical Sciences, University of Campania “Luigi Vanvitelli”, 80138 Naples, Italy; (D.B.); (R.R.); (A.V.); (S.I.); (A.D.F.); (L.C.); (M.A.); (M.L.M.); (R.M.); (D.C.); (F.C.S.); (L.R.); (A.M.); (L.E.A.)
| | - Valerio Rosato
- Liver Unit, Ospedale Evangelico Betania, 80147 Naples, Italy; (V.R.); (D.M.); (P.P.); (E.C.)
| | - Rachele Ruocco
- Department of Advanced Medical and Surgical Sciences, University of Campania “Luigi Vanvitelli”, 80138 Naples, Italy; (D.B.); (R.R.); (A.V.); (S.I.); (A.D.F.); (L.C.); (M.A.); (M.L.M.); (R.M.); (D.C.); (F.C.S.); (L.R.); (A.M.); (L.E.A.)
| | - Davide Mastrocinque
- Liver Unit, Ospedale Evangelico Betania, 80147 Naples, Italy; (V.R.); (D.M.); (P.P.); (E.C.)
| | - Angela Villani
- Department of Advanced Medical and Surgical Sciences, University of Campania “Luigi Vanvitelli”, 80138 Naples, Italy; (D.B.); (R.R.); (A.V.); (S.I.); (A.D.F.); (L.C.); (M.A.); (M.L.M.); (R.M.); (D.C.); (F.C.S.); (L.R.); (A.M.); (L.E.A.)
| | - Pasquale Perillo
- Liver Unit, Ospedale Evangelico Betania, 80147 Naples, Italy; (V.R.); (D.M.); (P.P.); (E.C.)
| | - Simona Imbriani
- Department of Advanced Medical and Surgical Sciences, University of Campania “Luigi Vanvitelli”, 80138 Naples, Italy; (D.B.); (R.R.); (A.V.); (S.I.); (A.D.F.); (L.C.); (M.A.); (M.L.M.); (R.M.); (D.C.); (F.C.S.); (L.R.); (A.M.); (L.E.A.)
| | - Augusto Delle Femine
- Department of Advanced Medical and Surgical Sciences, University of Campania “Luigi Vanvitelli”, 80138 Naples, Italy; (D.B.); (R.R.); (A.V.); (S.I.); (A.D.F.); (L.C.); (M.A.); (M.L.M.); (R.M.); (D.C.); (F.C.S.); (L.R.); (A.M.); (L.E.A.)
| | - Livio Criscuolo
- Department of Advanced Medical and Surgical Sciences, University of Campania “Luigi Vanvitelli”, 80138 Naples, Italy; (D.B.); (R.R.); (A.V.); (S.I.); (A.D.F.); (L.C.); (M.A.); (M.L.M.); (R.M.); (D.C.); (F.C.S.); (L.R.); (A.M.); (L.E.A.)
| | - Maria Alfano
- Department of Advanced Medical and Surgical Sciences, University of Campania “Luigi Vanvitelli”, 80138 Naples, Italy; (D.B.); (R.R.); (A.V.); (S.I.); (A.D.F.); (L.C.); (M.A.); (M.L.M.); (R.M.); (D.C.); (F.C.S.); (L.R.); (A.M.); (L.E.A.)
| | - Marco La Montagna
- Department of Advanced Medical and Surgical Sciences, University of Campania “Luigi Vanvitelli”, 80138 Naples, Italy; (D.B.); (R.R.); (A.V.); (S.I.); (A.D.F.); (L.C.); (M.A.); (M.L.M.); (R.M.); (D.C.); (F.C.S.); (L.R.); (A.M.); (L.E.A.)
| | - Antonio Russo
- Department of Mental Health and Public Medicine, University of Campania “Luigi Vanvitelli”, 80138 Naples, Italy;
| | - Raffaele Marfella
- Department of Advanced Medical and Surgical Sciences, University of Campania “Luigi Vanvitelli”, 80138 Naples, Italy; (D.B.); (R.R.); (A.V.); (S.I.); (A.D.F.); (L.C.); (M.A.); (M.L.M.); (R.M.); (D.C.); (F.C.S.); (L.R.); (A.M.); (L.E.A.)
| | - Domenico Cozzolino
- Department of Advanced Medical and Surgical Sciences, University of Campania “Luigi Vanvitelli”, 80138 Naples, Italy; (D.B.); (R.R.); (A.V.); (S.I.); (A.D.F.); (L.C.); (M.A.); (M.L.M.); (R.M.); (D.C.); (F.C.S.); (L.R.); (A.M.); (L.E.A.)
| | - Ferdinando Carlo Sasso
- Department of Advanced Medical and Surgical Sciences, University of Campania “Luigi Vanvitelli”, 80138 Naples, Italy; (D.B.); (R.R.); (A.V.); (S.I.); (A.D.F.); (L.C.); (M.A.); (M.L.M.); (R.M.); (D.C.); (F.C.S.); (L.R.); (A.M.); (L.E.A.)
| | - Luca Rinaldi
- Department of Advanced Medical and Surgical Sciences, University of Campania “Luigi Vanvitelli”, 80138 Naples, Italy; (D.B.); (R.R.); (A.V.); (S.I.); (A.D.F.); (L.C.); (M.A.); (M.L.M.); (R.M.); (D.C.); (F.C.S.); (L.R.); (A.M.); (L.E.A.)
| | - Aldo Marrone
- Department of Advanced Medical and Surgical Sciences, University of Campania “Luigi Vanvitelli”, 80138 Naples, Italy; (D.B.); (R.R.); (A.V.); (S.I.); (A.D.F.); (L.C.); (M.A.); (M.L.M.); (R.M.); (D.C.); (F.C.S.); (L.R.); (A.M.); (L.E.A.)
| | - Luigi Elio Adinolfi
- Department of Advanced Medical and Surgical Sciences, University of Campania “Luigi Vanvitelli”, 80138 Naples, Italy; (D.B.); (R.R.); (A.V.); (S.I.); (A.D.F.); (L.C.); (M.A.); (M.L.M.); (R.M.); (D.C.); (F.C.S.); (L.R.); (A.M.); (L.E.A.)
| | - Ernesto Claar
- Liver Unit, Ospedale Evangelico Betania, 80147 Naples, Italy; (V.R.); (D.M.); (P.P.); (E.C.)
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15
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Mak LY, Hui RWH, Cheung KS, Fung J, Seto WK, Yuen MF. Advances in determining new treatments for hepatitis B infection by utilizing existing and novel biomarkers. Expert Opin Drug Discov 2023; 18:401-416. [PMID: 36943183 DOI: 10.1080/17460441.2023.2192920] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/23/2023]
Abstract
INTRODUCTION Chronic hepatitis B (CHB) infection is a major global health threat and accounts for significant liver-related morbidity and mortality. An improved understanding of how hepatitis B virus (HBV) interacts with the host immune system allows the discovery of novel biomarkers and new treatment options. Viral biomarkers including hepatitis B surface antigen (HBsAg) and newer ones like HBV RNA and hepatitis B core-related antigen appear to be useful to select patients who are likely to benefit from cessation of long-term antiviral therapy. These markers can also help to confirm target engagement for novel compounds, and efficacy in HBsAg reduction and seroclearance is deemed essential as this is how the current treatment endpoint of functional cure is defined. AREAS COVERED In this review, the authors discuss the current standard of care and the gaps between such standard and the ideal goals for treatment in CHB. The authors highlight novel viral and immunological biomarkers that are potentially useful to evaluate treatment response. Novel treatment approaches in relation to these novel biomarkers are also evaluated. EXPERT OPINION Novel serum viral biomarkers and immunological markers are indispensable in the HBV functional cure program. These will likely become part of standard monitoring soon.
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Affiliation(s)
- Lung-Yi Mak
- Department of Medicine, School of Clinical Medicine, Pokfulam, Hong Kong
- State Key Laboratory of Liver Research, The University of Hong Kong, Pok Fu Lam, Hong Kong
| | - Rex Wan-Hin Hui
- Department of Medicine, School of Clinical Medicine, Pokfulam, Hong Kong
| | - Ka-Shing Cheung
- Department of Medicine, School of Clinical Medicine, Pokfulam, Hong Kong
| | - James Fung
- Department of Medicine, School of Clinical Medicine, Pokfulam, Hong Kong
- State Key Laboratory of Liver Research, The University of Hong Kong, Pok Fu Lam, Hong Kong
| | - Wai-Kay Seto
- Department of Medicine, School of Clinical Medicine, Pokfulam, Hong Kong
- State Key Laboratory of Liver Research, The University of Hong Kong, Pok Fu Lam, Hong Kong
| | - Man-Fung Yuen
- Department of Medicine, School of Clinical Medicine, Pokfulam, Hong Kong
- State Key Laboratory of Liver Research, The University of Hong Kong, Pok Fu Lam, Hong Kong
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16
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Yang H, Yao W, Yang J. Overview of the development of HBV small molecule inhibitors. Eur J Med Chem 2023; 249:115128. [PMID: 36709647 DOI: 10.1016/j.ejmech.2023.115128] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2022] [Revised: 01/13/2023] [Accepted: 01/15/2023] [Indexed: 01/28/2023]
Abstract
Like tuberculosis and Acquired Immune Deficiency Syndrome (AIDS), hepatitis B is a globally recognized major public health threat. Although there are many small-molecule drugs for the treatment of hepatitis B, the approved drugs cannot eradicate the pathogenic culprit covalently closed circular DNA in patients, so the patients need long-term medication to control HBV amplification. Driven by a high unmet medical need, many pharmaceutical companies and research institutions have been engaged in the development of anti-HBV drugs to achieve a functional cure for chronic hepatitis B as soon as possible. This review summarizes the pathogenesis of hepatitis B virus and the research progress in the development of anti-HBV small molecule drugs, and introduces the cccDNA formation and transcription inhibitors and core inhibitors in detail, especially emphasizes the role of chinese herbal medicine in the treatment of chronic hepatitis B. Furthermore, this review proposes three potential strategies for cccDNA eradication in the future. We believe this review will provide meaningful guidance to achieve a functional cure for viral hepatitis B in the future.
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Affiliation(s)
- Huihui Yang
- School of Health and Life Sciences, University of Health and Rehabilitation Sciences, Qingdao, 266001, China
| | - Weiwei Yao
- School of Health and Life Sciences, University of Health and Rehabilitation Sciences, Qingdao, 266001, China
| | - Jinfei Yang
- School of Health and Life Sciences, University of Health and Rehabilitation Sciences, Qingdao, 266001, China.
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17
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Heat Shock Protein Family A Member 1 Promotes Intracellular Amplification of Hepatitis B Virus Covalently Closed Circular DNA. J Virol 2023; 97:e0126122. [PMID: 36519896 PMCID: PMC9888207 DOI: 10.1128/jvi.01261-22] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
Hepatitis B virus (HBV) contains a partially double-stranded relaxed circular DNA (rcDNA) genome that is converted into a covalently closed circular DNA (cccDNA) in the nucleus of the infected hepatocyte by cellular DNA repair machinery. cccDNA associates with nucleosomes to form a minichromosome that transcribes RNA to support the expression of viral proteins and reverse transcriptional replication of viral DNA. In addition to the de novo synthesis from incoming virion rcDNA, cccDNA can also be synthesized from rcDNA in the progeny nucleocapsids within the cytoplasm of infected hepatocytes via the intracellular amplification pathway. In our efforts to identify cellular DNA repair proteins required for cccDNA synthesis using a chemogenetic screen, we found that B02, a small-molecule inhibitor of DNA homologous recombination repair protein RAD51, significantly enhanced the synthesis of cccDNA via the intracellular amplification pathway in human hepatoma cells. Ironically, neither small interfering RNA (siRNA) knockdown of RAD51 expression nor treatment with another structurally distinct RAD51 inhibitor or activator altered cccDNA amplification. Instead, it was found that B02 treatment significantly elevated the levels of multiple heat shock protein mRNA, and siRNA knockdown of HSPA1 expression or treatment with HSPA1 inhibitors significantly attenuated B02 enhancement of cccDNA amplification. Moreover, B02-enhanced cccDNA amplification was efficiently inhibited by compounds that selectively inhibit DNA polymerase α or topoisomerase II, the enzymes required for cccDNA intracellular amplification. Our results thus indicate that B02 treatment induces a heat shock protein-mediated cellular response that positively regulates the conversion of rcDNA into cccDNA via the authentic intracellular amplification pathway. IMPORTANCE Elimination or functional inactivation of cccDNA minichromosomes in HBV-infected hepatocytes is essential for the cure of chronic hepatitis B virus (HBV) infection. However, lack of knowledge of the molecular mechanisms of cccDNA metabolism and regulation hampers the development of antiviral drugs to achieve this therapeutic goal. Our findings reported here imply that enhanced cccDNA amplification may occur under selected pathobiological conditions, such as cellular stress, to subvert the dilution or elimination of cccDNA and maintain the persistence of HBV infection. Therapeutic inhibition of HSPA1-enhanced cccDNA amplification under these pathobiological conditions should facilitate the elimination of cccDNA and cure of chronic hepatitis B.
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18
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Identification of the Interaction between Minichromosome Maintenance Proteins and the Core Protein of Hepatitis B Virus. Curr Issues Mol Biol 2023; 45:752-764. [PMID: 36661536 PMCID: PMC9857746 DOI: 10.3390/cimb45010050] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/26/2022] [Revised: 01/10/2023] [Accepted: 01/13/2023] [Indexed: 01/18/2023] Open
Abstract
Chronic HBV infection is a major cause of cirrhosis and hepatocellular carcinoma. Finding host factors involved in the viral life cycle and elucidating their mechanisms is essential for developing innovative strategies for treating HBV. The HBV core protein has pleiotropic roles in HBV replication; thus, finding the interactions between the core protein and host factors is important in clarifying the mechanism of viral infection and proliferation. Recent studies have revealed that core proteins are involved in cccDNA formation, transcriptional regulation, and RNA metabolism, in addition to their primary functions of capsid formation and pgRNA packaging. Here, we report the interaction of the core protein with MCMs, which have an essential role in host DNA replication. The knockdown of MCM2 led to increased viral replication during infection, suggesting that MCM2 serves as a restriction factor for HBV proliferation. This study opens the possibility of elucidating the relationship between core proteins and host factors and their function in viral proliferation.
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19
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The scientific basis of combination therapy for chronic hepatitis B functional cure. Nat Rev Gastroenterol Hepatol 2023; 20:238-253. [PMID: 36631717 DOI: 10.1038/s41575-022-00724-5] [Citation(s) in RCA: 72] [Impact Index Per Article: 36.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 11/24/2022] [Indexed: 01/13/2023]
Abstract
Functional cure of chronic hepatitis B (CHB) - or hepatitis B surface antigen (HBsAg) loss after 24 weeks off therapy - is now the goal of treatment, but is rarely achieved with current therapy. Understanding the hepatitis B virus (HBV) life cycle and immunological defects that lead to persistence can identify targets for novel therapy. Broadly, treatments fall into three categories: those that reduce viral replication, those that reduce antigen load and immunotherapies. Profound viral suppression alone does not achieve quantitative (q)HBsAg reduction or HBsAg loss. Combining nucleos(t)ide analogues and immunotherapy reduces qHBsAg levels and induces HBsAg loss in some patients, particularly those with low baseline qHBsAg levels. Even agents that are specifically designed to reduce viral antigen load might not be able to achieve sustained HBsAg loss when used alone. Thus, rationale exists for the use of combinations of all three therapy types. Monitoring during therapy is important not just to predict HBsAg loss but also to understand mechanisms of HBsAg loss using viral and immunological biomarkers, and in selected cases intrahepatic sampling. We consider various paths to functional cure of CHB and the need to individualize treatment of this heterogeneous infection until a therapeutic avenue for all patients with CHB is available.
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A road to contemporary era of hepatitis B virus regimen replacing existing therapeutics exploiting plant secondary metabolites as emerging heroes in exploring drugs: An expedition for a functional cure. GENE REPORTS 2023. [DOI: 10.1016/j.genrep.2023.101743] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
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21
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Verrier ER, Ligat G, Heydmann L, Doernbrack K, Miller J, Maglott-Roth A, Jühling F, El Saghire H, Heuschkel MJ, Fujiwara N, Hsieh SY, Hoshida Y, Root DE, Felli E, Pessaux P, Mukherji A, Mailly L, Schuster C, Brino L, Nassal M, Baumert TF. Cell-based cccDNA reporter assay combined with functional genomics identifies YBX1 as HBV cccDNA host factor and antiviral candidate target. Gut 2022; 72:gutjnl-2020-323665. [PMID: 36591611 PMCID: PMC10423543 DOI: 10.1136/gutjnl-2020-323665] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/19/2020] [Accepted: 11/24/2022] [Indexed: 01/03/2023]
Abstract
OBJECTIVES Chronic hepatitis B virus (HBV) infection is a leading cause of liver disease and hepatocellular carcinoma. A key feature of HBV replication is the synthesis of the covalently close circular (ccc)DNA, not targeted by current treatments and whose elimination would be crucial for viral cure. To date, little is known about cccDNA formation. One major challenge to address this urgent question is the absence of robust models for the study of cccDNA biology. DESIGN We established a cell-based HBV cccDNA reporter assay and performed a loss-of-function screen targeting 239 genes encoding the human DNA damage response machinery. RESULTS Overcoming the limitations of current models, the reporter assay enables to quantity cccDNA levels using a robust ELISA as a readout. A loss-of-function screen identified 27 candidate cccDNA host factors, including Y box binding protein 1 (YBX1), a DNA binding protein regulating transcription and translation. Validation studies in authentic infection models revealed a robust decrease in HBV cccDNA levels following silencing, providing proof-of-concept for the importance of YBX1 in the early steps of the HBV life cycle. In patients, YBX1 expression robustly correlates with both HBV load and liver disease progression. CONCLUSION Our cell-based reporter assay enables the discovery of HBV cccDNA host factors including YBX1 and is suitable for the characterisation of cccDNA-related host factors, antiviral targets and compounds.
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Affiliation(s)
- Eloi R Verrier
- Université de Strasbourg, Inserm, Institut de Recherche sur les Maladies Virales et Hépatiques UMRS 1110, Strasbourg, France
| | - Gaëtan Ligat
- Université de Strasbourg, Inserm, Institut de Recherche sur les Maladies Virales et Hépatiques UMRS 1110, Strasbourg, France
| | - Laura Heydmann
- Université de Strasbourg, Inserm, Institut de Recherche sur les Maladies Virales et Hépatiques UMRS 1110, Strasbourg, France
| | - Katharina Doernbrack
- Department of Internal Medicine II/Molecular Biology, University Hospital Freiburg, Freiburg, Germany
| | - Julija Miller
- Department of Internal Medicine II/Molecular Biology, University Hospital Freiburg, Freiburg, Germany
| | | | - Frank Jühling
- Université de Strasbourg, Inserm, Institut de Recherche sur les Maladies Virales et Hépatiques UMRS 1110, Strasbourg, France
| | - Houssein El Saghire
- Université de Strasbourg, Inserm, Institut de Recherche sur les Maladies Virales et Hépatiques UMRS 1110, Strasbourg, France
| | - Margaux J Heuschkel
- Université de Strasbourg, Inserm, Institut de Recherche sur les Maladies Virales et Hépatiques UMRS 1110, Strasbourg, France
| | - Naoto Fujiwara
- Department of Internal Medicine, Liver Tumor Translational Research Program, Simmons Comprehensive Cancer Center, Division of Digestive and Liver Diseases, University of Texas Southwestern Medical Center, Dallas, Texas, USA
| | - Sen-Yung Hsieh
- Department of Gastroenterology and Hepatology, Chang Gung Memorial Hospital, Taoyuan, Taiwan
| | - Yujin Hoshida
- Department of Internal Medicine, Liver Tumor Translational Research Program, Simmons Comprehensive Cancer Center, Division of Digestive and Liver Diseases, University of Texas Southwestern Medical Center, Dallas, Texas, USA
| | - David E Root
- Broad Institute of Massachusetts Institute of Technology and Harvard, Cambridge, Massachusetts, USA
| | - Emanuele Felli
- Université de Strasbourg, Inserm, Institut de Recherche sur les Maladies Virales et Hépatiques UMRS 1110, Strasbourg, France
- Institut Hospitalo-Universitaire, Pôle Hépato-digestif, Nouvel Hôpital Civil, Strasbourg, France
| | - Patrick Pessaux
- Université de Strasbourg, Inserm, Institut de Recherche sur les Maladies Virales et Hépatiques UMRS 1110, Strasbourg, France
- Institut Hospitalo-Universitaire, Pôle Hépato-digestif, Nouvel Hôpital Civil, Strasbourg, France
| | - Atish Mukherji
- Université de Strasbourg, Inserm, Institut de Recherche sur les Maladies Virales et Hépatiques UMRS 1110, Strasbourg, France
| | - Laurent Mailly
- Université de Strasbourg, Inserm, Institut de Recherche sur les Maladies Virales et Hépatiques UMRS 1110, Strasbourg, France
| | - Catherine Schuster
- Université de Strasbourg, Inserm, Institut de Recherche sur les Maladies Virales et Hépatiques UMRS 1110, Strasbourg, France
| | - Laurent Brino
- IGBMC, Plateforme de Criblage Haut-débit, Illkirch, France
| | - Michael Nassal
- Department of Internal Medicine II/Molecular Biology, University Hospital Freiburg, Freiburg, Germany
| | - Thomas F Baumert
- Université de Strasbourg, Inserm, Institut de Recherche sur les Maladies Virales et Hépatiques UMRS 1110, Strasbourg, France
- Institut Hospitalo-Universitaire, Pôle Hépato-digestif, Nouvel Hôpital Civil, Strasbourg, France
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22
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Discovery, enantioselective synthesis of myrtucommulone E analogues as tyrosyl-DNA phosphodiesterase 2 inhibitors and their biological activities. Eur J Med Chem 2022; 238:114445. [DOI: 10.1016/j.ejmech.2022.114445] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2022] [Revised: 04/26/2022] [Accepted: 05/05/2022] [Indexed: 11/20/2022]
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23
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Bhat S, Kazim SN. HBV cccDNA-A Culprit and Stumbling Block for the Hepatitis B Virus Infection: Its Presence in Hepatocytes Perplexed the Possible Mission for a Functional Cure. ACS OMEGA 2022; 7:24066-24081. [PMID: 35874215 PMCID: PMC9301636 DOI: 10.1021/acsomega.2c02216] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/17/2023]
Abstract
Hepatitis B virus infection (HBV) is still a big health problem across the globe. It has been linked to the development of liver cirrhosis and hepatocellular carcinoma and can trigger different types of liver damage. Existing medicines are unable to disable covalently closed circular DNA (cccDNA), which may result in HBV persistence and recurrence. The current therapeutic goal is to achieve a functional cure, which means HBV-DNA no longer exists when treatment stops and the absence of HBsAg seroclearance. However, due to the presence of integrated HBV DNA and cccDNA functional treatment is now regarded to be difficult. In order to uncover pathways for potential therapeutic targets and identify medicines that could result in large rates of functional cure, a thorough understanding of the virus' biology is required. The proteins of the virus and episomal cccDNA are thought to be critical for the management and support of the HBV replication cycle as they interact directly with the host proteome to establish the best atmosphere for the virus while evading immune detection. The breakthroughs of host dependence factors, cccDNA transcription, epigenetic regulation, and immune-mediated breakdown have all produced significant progress in our understanding of cccDNA biology during the past decade. There are some strategies where cccDNA can be targeted either in a direct or indirect way and are presently at the point of discovery or preclinical or early clinical advancement. Editing of genomes, techniques targeting host dependence factors or epigenetic gene maintenance, nucleocapsid modulators, miRNA, siRNA, virion secretory inhibitors, and immune-mediated degradation are only a few examples. Though cccDNA approaches for direct targeting are still in the early stages of development, the assembly of capsid modulators and immune-reliant treatments have made it to the clinic. Clinical trials are currently being conducted to determine their efficiency and safety in patients, as well as their effect on viral cccDNA. The influence of recent breakthroughs in the development of new treatment techniques on cccDNA biology is also summarized in this review.
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Affiliation(s)
- Sajad
Ahmad Bhat
- Jamia Millia Islamia Central University, Centre for Interdisciplinary Research in Basic Sciences, New Delhi 110025, India
| | - Syed Naqui Kazim
- Jamia Millia Islamia Central University, Centre for Interdisciplinary Research in Basic Sciences, New Delhi 110025, India
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24
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Bianca C, Sidhartha E, Tiribelli C, El-Khobar KE, Sukowati CHC. Role of hepatitis B virus in development of hepatocellular carcinoma: Focus on covalently closed circular DNA. World J Hepatol 2022; 14:866-884. [PMID: 35721287 PMCID: PMC9157711 DOI: 10.4254/wjh.v14.i5.866] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/30/2021] [Revised: 01/31/2022] [Accepted: 04/25/2022] [Indexed: 02/06/2023] Open
Abstract
Chronic infection with hepatitis B virus (HBV) remains a major global health problem, especially in developing countries. It may lead to prolonged liver damage, fibrosis, cirrhosis, and hepatocellular carcinoma. Persistent chronic HBV infection is related to host immune response and the stability of the covalently closed circular DNA (cccDNA) in human hepatocytes. In addition to being essential for viral transcription and replication, cccDNA is also suspected to play a role in persistent HBV infections or hepatitis relapses since cccDNA is very stable in non-dividing human hepatocytes. Understanding the pathogenicity and oncogenicity of HBV components would be essential in the development of new diagnostic tools and treatment strategies. This review summarizes the role and molecular mechanisms of HBV cccDNA in hepatocyte transformation and hepatocarcinogenesis and current efforts to its detection and targeting.
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Affiliation(s)
- Claryssa Bianca
- Department of Biomedicine, Indonesia International Institute for Life Sciences, Jakarta 13210, Indonesia
| | - Elizabeth Sidhartha
- Department of Biomedicine, Indonesia International Institute for Life Sciences, Jakarta 13210, Indonesia
| | - Claudio Tiribelli
- Centro Studi Fegato, Fondazione Italiana Fegato ONLUS, Trieste 34149, Italy
| | - Korri Elvanita El-Khobar
- Eijkman Center for Molecular Biology, National Research and Innovation Agency (BRIN), Jakarta 10340, Indonesia
| | - Caecilia H C Sukowati
- Centro Studi Fegato, Fondazione Italiana Fegato ONLUS, Trieste 34149, Italy
- Eijkman Center for Molecular Biology, National Research and Innovation Agency (BRIN), Jakarta 10340, Indonesia.
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25
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HIRA Supports Hepatitis B Virus Minichromosome Establishment and Transcriptional Activity in Infected Hepatocytes. Cell Mol Gastroenterol Hepatol 2022; 14:527-551. [PMID: 35643233 PMCID: PMC9304598 DOI: 10.1016/j.jcmgh.2022.05.007] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/28/2021] [Revised: 05/11/2022] [Accepted: 05/18/2022] [Indexed: 12/10/2022]
Abstract
BACKGROUND & AIMS Upon hepatitis B virus (HBV) infection, partially double-stranded viral DNA converts into a covalently closed circular chromatinized episomal structure (cccDNA). This form represents the long-lived genomic reservoir responsible for viral persistence in the infected liver. Although the involvement of host cell DNA damage response in cccDNA formation has been established, this work investigated the yet-to-be-identified histone dynamics on cccDNA during early phases of infection in human hepatocytes. METHODS Detailed studies of host chromatin-associated factors were performed in cell culture models of natural infection (ie, Na+-taurocholate cotransporting polypeptide (NTCP)-overexpressing HepG2 cells, HepG2hNTCP) and primary human hepatocytes infected with HBV, by cccDNA-specific chromatin immunoprecipitation and loss-of-function experiments during early kinetics of viral minichromosome establishment and onset of viral transcription. RESULTS Our results show that cccDNA formation requires the deposition of the histone variant H3.3 via the histone regulator A (HIRA)-dependent pathway. This occurs simultaneously with repair of the cccDNA precursor and independently from de novo viral protein expression. Moreover, H3.3 in its S31 phosphorylated form appears to be the preferential H3 variant found on transcriptionally active cccDNA in infected cultured cells and human livers. HIRA depletion after cccDNA pool establishment showed that HIRA recruitment is required for viral transcription and RNA production. CONCLUSIONS Altogether, we show a crucial role for HIRA in the interplay between HBV genome and host cellular machinery to ensure the formation and active transcription of the viral minichromosome in infected hepatocytes.
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26
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Hepatitis B Virus-Associated Hepatocellular Carcinoma. Viruses 2022; 14:v14050986. [PMID: 35632728 PMCID: PMC9146458 DOI: 10.3390/v14050986] [Citation(s) in RCA: 79] [Impact Index Per Article: 26.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2022] [Revised: 05/02/2022] [Accepted: 05/03/2022] [Indexed: 02/06/2023] Open
Abstract
Hepatitis B virus (HBV) is DNA-based virus, member of the Hepadnaviridae family, which can cause liver disease and increased risk of hepatocellular carcinoma (HCC) in infected individuals, replicating within the hepatocytes and interacting with several cellular proteins. Chronic hepatitis B can progressively lead to liver cirrhosis, which is an independent risk factor for HCC. Complications as liver decompensation or HCC impact the survival of HBV patients and concurrent HDV infection worsens the disease. The available data provide evidence that HBV infection is associated with the risk of developing HCC with or without an underlying liver cirrhosis, due to various direct and indirect mechanisms promoting hepatocarcinogenesis. The molecular profile of HBV-HCC is extensively and continuously under study, and it is the result of altered molecular pathways, which modify the microenvironment and lead to DNA damage. HBV produces the protein HBx, which has a central role in the oncogenetic process. Furthermore, the molecular profile of HBV-HCC was recently discerned from that of HDV-HCC, despite the obligatory dependence of HDV on HBV. Proper management of the underlying HBV-related liver disease is fundamental, including HCC surveillance, viral suppression, and application of adequate predictive models. When HBV-HCC occurs, liver function and HCC characteristics guide the physician among treatment strategies but always considering the viral etiology in the treatment choice.
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27
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Tati S, Alisaraie L. Recruitment of dynein and kinesin to viral particles. FASEB J 2022; 36:e22311. [DOI: 10.1096/fj.202101900rr] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2021] [Revised: 03/14/2022] [Accepted: 03/29/2022] [Indexed: 11/11/2022]
Affiliation(s)
- Sayi’Mone Tati
- School of Pharmacy Memorial University of Newfoundland St. John’s Newfoundland Canada
| | - Laleh Alisaraie
- School of Pharmacy Memorial University of Newfoundland St. John’s Newfoundland Canada
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28
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PRKDC promotes hepatitis B virus transcription through enhancing the binding of RNA Pol II to cccDNA. Cell Death Dis 2022; 13:404. [PMID: 35468873 PMCID: PMC9038722 DOI: 10.1038/s41419-022-04852-3] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2021] [Revised: 04/06/2022] [Accepted: 04/11/2022] [Indexed: 12/21/2022]
Abstract
Hepatitis B virus infection remains a major health problem worldwide due to its high risk of liver failure and hepatocellular carcinoma. Covalently closed circular DNA (cccDNA), which is present as an individual minichromosome, serves as the template for transcription of all viral RNAs and pla ays critical role in viral persistence. Therefore, there is an urgent need to gain broader insight into the transcription regulation of cccDNA. Here, we combined a modified Clustered Regularly Interspaced Short Palindromic Repeats (CRISPR) with an engineered ascorbate peroxidase 2 (APEX2) to identify cccDNA associated proteins systematically in living cells. By functional screening, we verified that protein kinase, DNA-activated, catalytic subunit (PRKDC) was an effective activator of HBV cccDNA transcription in HBV-infected HepG2-NTCP cells and primary human hepatocytes. Mechanismly, PRKDC interacted with POLR2A and POLR2B, the two largest subunits of RNA polymerase II (Pol II) and recruited Pol II to HBV cccDNA minichromosome in a kinase-dependent manner. PRKDC knockdown or inhibitor treatment significantly decreased the enrichment of POLR2A and POLR2B on cccDNA, as well as reducing the levels of cccDNA associated Pol II Ser5 and Ser2 phosphorylation, which eventually inhibited the HBV cccDNA activity. Collectively, these findings give us new insights into cccDNA transcription regulation, thus providing new potential targets for HBV treatment in patients.
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29
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Kitamura K, Fukano K, Que L, Li Y, Wakae K, Muramatsu M. Activities of endogenous APOBEC3s and uracil-DNA-glycosylase affect the hypermutation frequency of hepatitis B virus cccDNA. J Gen Virol 2022; 103. [PMID: 35438620 DOI: 10.1099/jgv.0.001732] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
The covalently closed circular DNA (cccDNA) of hepatitis B virus (HBV) plays a key role in the persistence of viral infection. We have previously shown that overexpression of an antiviral factor APOBEC3G (A3G) induces hypermutation in duck HBV (DHBV) cccDNA, whereas uracil-DNA-glycosylase (UNG) reduces these mutations. In this study, using cell-culture systems, we examined whether endogenous A3s and UNG affect HBV cccDNA mutation frequency. IFNγ stimulation induced a significant increase in endogenous A3G expression and cccDNA hypermutation. UNG inhibition enhanced the IFNγ-mediated hypermutation frequency. Transfection of reconstructed cccDNA revealed that this enhanced hypermutation caused a reduction in viral replication. These results suggest that the balance of endogenous A3s and UNG activities affects HBV cccDNA mutation and replication competency.
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Affiliation(s)
- Kouichi Kitamura
- Department of Virology II, National Institute of Infectious Diseases, Murayama branch, 4-7-1 Gakuen, Musashi-murayama, Tokyo 208-0011, Japan
| | - Kento Fukano
- Department of Virology II, National Institute of Infectious Diseases, Murayama branch, 4-7-1 Gakuen, Musashi-murayama, Tokyo 208-0011, Japan
| | - Lusheng Que
- Department of Virology II, National Institute of Infectious Diseases, Murayama branch, 4-7-1 Gakuen, Musashi-murayama, Tokyo 208-0011, Japan
| | - Yingfang Li
- Department of Virology II, National Institute of Infectious Diseases, Murayama branch, 4-7-1 Gakuen, Musashi-murayama, Tokyo 208-0011, Japan
| | - Kousho Wakae
- Department of Virology II, National Institute of Infectious Diseases, Murayama branch, 4-7-1 Gakuen, Musashi-murayama, Tokyo 208-0011, Japan
| | - Masamichi Muramatsu
- Department of Virology II, National Institute of Infectious Diseases, Murayama branch, 4-7-1 Gakuen, Musashi-murayama, Tokyo 208-0011, Japan
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30
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Hepatitis B Viral Protein HBx and the Molecular Mechanisms Modulating the Hallmarks of Hepatocellular Carcinoma: A Comprehensive Review. Cells 2022; 11:cells11040741. [PMID: 35203390 PMCID: PMC8870387 DOI: 10.3390/cells11040741] [Citation(s) in RCA: 39] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2021] [Revised: 02/10/2022] [Accepted: 02/16/2022] [Indexed: 02/06/2023] Open
Abstract
With 296 million cases estimated worldwide, chronic hepatitis B virus (HBV) infection is the most common risk factor for hepatocellular carcinoma (HCC). HBV-encoded oncogene X protein (HBx), a key multifunctional regulatory protein, drives viral replication and interferes with several cellular signalling pathways that drive virus-associated hepatocarcinogenesis. This review article provides a comprehensive overview of the role of HBx in modulating the various hallmarks of HCC by supporting tumour initiation, progression, invasion and metastasis. Understanding HBx-mediated dimensions of complexity in driving liver malignancies could provide the key to unlocking novel and repurposed combinatorial therapies to combat HCC.
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31
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Abstract
Hepatitis B virus (HBV) is a hepatotropic virus and an important human pathogen. There are an estimated 296 million people in the world that are chronically infected by this virus, and many of them will develop severe liver diseases including hepatitis, cirrhosis and hepatocellular carcinoma (HCC). HBV is a small DNA virus that replicates via the reverse transcription pathway. In this review, we summarize the molecular pathways that govern the replication of HBV and its interactions with host cells. We also discuss viral and non-viral factors that are associated with HBV-induced carcinogenesis and pathogenesis, as well as the role of host immune responses in HBV persistence and liver pathogenesis.
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Affiliation(s)
- Yu-Chen Chuang
- Department of Molecular Microbiology and Immunology, University of Southern California Keck School of Medicine, Los Angeles, CA 90089, USA
| | - Kuen-Nan Tsai
- Department of Molecular Microbiology and Immunology, University of Southern California Keck School of Medicine, Los Angeles, CA 90089, USA
| | - Jing-Hsiung James Ou
- Department of Molecular Microbiology and Immunology, University of Southern California Keck School of Medicine, Los Angeles, CA 90089, USA
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32
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Bhattacharjee S, Rehman I, Nandy S, Das BB. Post-translational regulation of Tyrosyl-DNA phosphodiesterase (TDP1 and TDP2) for the repair of the trapped topoisomerase-DNA covalent complex. DNA Repair (Amst) 2022; 111:103277. [DOI: 10.1016/j.dnarep.2022.103277] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2021] [Revised: 12/24/2021] [Accepted: 01/20/2022] [Indexed: 12/23/2022]
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33
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Zhang X, Wang Y, Yang G. Research progress in hepatitis B virus covalently closed circular DNA. Cancer Biol Med 2021; 19:j.issn.2095-3941.2021.0454. [PMID: 34931766 PMCID: PMC9088183 DOI: 10.20892/j.issn.2095-3941.2021.0454] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2021] [Accepted: 11/16/2021] [Indexed: 11/28/2022] Open
Abstract
Hepatitis B virus (HBV) infections are a global public health issue. HBV covalently closed circular DNA (cccDNA), the template for the transcription of viral RNAs, is a key factor in the HBV replication cycle. Notably, many host factors involved in HBV cccDNA epigenetic modulation promote the development of hepatocellular carcinoma (HCC). The HBV cccDNA minichromosome is a clinical obstacle that cannot be efficiently eliminated. In this review, we provide an update on the advances in research on HBV cccDNA and further discuss factors affecting the modulation of HBV cccDNA. Hepatitis B virus X protein (HBx) contributes to HBV cccDNA transcription and the development of hepatocarcinogenesis through modulating host epigenetic regulatory factors, thus linking the cccDNA to hepatocarcinogenesis. The measurable serological biomarkers of continued transcription of cccDNA, the effects of anti-HBV drugs on cccDNA, and potential therapeutic strategies targeting cccDNA are discussed in detail. Thus, this review describes new insights into HBV cccDNA mechanisms and therapeutic strategies for cleaning cccDNA, which will benefit patients with liver diseases.
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Affiliation(s)
- Xiaodong Zhang
- Department of Gastrointestinal Cancer Biology, Liver Cancer Center, Tianjin Medical University Cancer Institute & Hospital, National Clinical Research Center for Cancer, Key Laboratory of Cancer Prevention and Therapy, Tianjin, Tianjin’s Clinical Research Center for Cancer, Tianjin 300060, China
| | - Yufei Wang
- Department of Cancer Research, College of Life Sciences, Nankai University, Tianjin 300071, China
| | - Guang Yang
- Department of Gastrointestinal Cancer Biology, Liver Cancer Center, Tianjin Medical University Cancer Institute & Hospital, National Clinical Research Center for Cancer, Key Laboratory of Cancer Prevention and Therapy, Tianjin, Tianjin’s Clinical Research Center for Cancer, Tianjin 300060, China
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34
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Kim H, Ko C, Lee JY, Kim M. Current Progress in the Development of Hepatitis B Virus Capsid Assembly Modulators: Chemical Structure, Mode-of-Action and Efficacy. Molecules 2021; 26:molecules26247420. [PMID: 34946502 PMCID: PMC8705634 DOI: 10.3390/molecules26247420] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2021] [Revised: 11/24/2021] [Accepted: 12/02/2021] [Indexed: 12/15/2022] Open
Abstract
Hepatitis B virus (HBV) is a major causative agent of human hepatitis. Its viral genome comprises partially double-stranded DNA, which is complexed with viral polymerase within an icosahedral capsid consisting of a dimeric core protein. Here, we describe the effects of capsid assembly modulators (CAMs) on the geometric or kinetic disruption of capsid construction and the virus life cycle. We highlight classical, early-generation CAMs such as heteroaryldihydropyrimidines, phenylpropenamides or sulfamoylbenzamides, and focus on the chemical structure and antiviral efficacy of recently identified non-classical CAMs, which consist of carboxamides, aryl ureas, bithiazoles, hydrazones, benzylpyridazinones, pyrimidines, quinolines, dyes, and antimicrobial compounds. We summarize the therapeutic efficacy of four representative classical compounds with data from clinical phase 1 studies in chronic HBV patients. Most of these compounds are in phase 2 trials, either as monotherapy or in combination with approved nucleos(t)ides drugs or other immunostimulatory molecules. As followers of the early CAMs, the therapeutic efficacy of several non-classical CAMs has been evaluated in humanized mouse models of HBV infection. It is expected that these next-generation HBV CAMs will be promising candidates for a series of extended human clinical trials.
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Affiliation(s)
- Hyejin Kim
- Correspondence: (H.K.); (M.K.); Tel.: +82-42-860-7130 (H.K.); +82-42-860-7540 (M.K.)
| | | | | | - Meehyein Kim
- Correspondence: (H.K.); (M.K.); Tel.: +82-42-860-7130 (H.K.); +82-42-860-7540 (M.K.)
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35
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Abstract
Hepatitis B virus (HBV) is a hepatotropic, partially double-stranded DNA virus that replicates by reverse transcription and is a major cause of chronic liver disease and hepatocellular carcinoma. Reverse transcription is catalyzed by the four-domain multifunctional HBV polymerase (P) protein that has protein-priming, RNA- and DNA-dependent DNA synthesis (i.e., reverse transcriptase), and ribonuclease H activities. P also likely promotes the three strand transfers that occur during reverse transcription, and it may participate in immune evasion by HBV. Reverse transcription is primed by a tyrosine residue in the amino-terminal domain of P, and P remains covalently attached to the product DNA throughout reverse transcription. The reverse transcriptase activity of P is the target for the nucleos(t)ide analog drugs that dominate HBV treatment, and P is the target of ongoing efforts to develop new drugs against both the reverse transcriptase and ribonuclease H activities. Despite the unusual reverse transcription pathway catalyzed by P and the importance of P to HBV therapy, understanding the enzymology and structure of HBV P severely lags that of the retroviral reverse transcriptases due to substantial technical challenges to studying the enzyme. Obtaining a better understanding of P will broaden our appreciation of the diversity among reverse transcribing elements in nature, and will help improve treatment for people chronically infected with HBV.
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Affiliation(s)
- Daniel N Clark
- Department of Microbiology, Weber State University, Ogden, UT, United States
| | - Razia Tajwar
- Department of Molecular Microbiology and Immunology, Saint Louis University School of Medicine, Saint Louis, MO, United States
| | - Jianming Hu
- Department of Microbiology and Immunology, The Pennsylvania State University College of Medicine, Hershey, PA, United States
| | - John E Tavis
- Department of Molecular Microbiology and Immunology, Saint Louis University School of Medicine, Saint Louis, MO, United States.
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36
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Niklasch M, Zimmermann P, Nassal M. The Hepatitis B Virus Nucleocapsid-Dynamic Compartment for Infectious Virus Production and New Antiviral Target. Biomedicines 2021; 9:1577. [PMID: 34829806 PMCID: PMC8615760 DOI: 10.3390/biomedicines9111577] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2021] [Revised: 10/19/2021] [Accepted: 10/21/2021] [Indexed: 12/11/2022] Open
Abstract
Hepatitis B virus (HBV) is a small enveloped DNA virus which replicates its tiny 3.2 kb genome by reverse transcription inside an icosahedral nucleocapsid, formed by a single ~180 amino acid capsid, or core, protein (Cp). HBV causes chronic hepatitis B (CHB), a severe liver disease responsible for nearly a million deaths each year. Most of HBV's only seven primary gene products are multifunctional. Though less obvious than for the multi-domain polymerase, P protein, this is equally crucial for Cp with its multiple roles in the viral life-cycle. Cp provides a stable genome container during extracellular phases, allows for directed intracellular genome transport and timely release from the capsid, and subsequent assembly of new nucleocapsids around P protein and the pregenomic (pg) RNA, forming a distinct compartment for reverse transcription. These opposing features are enabled by dynamic post-transcriptional modifications of Cp which result in dynamic structural alterations. Their perturbation by capsid assembly modulators (CAMs) is a promising new antiviral concept. CAMs inappropriately accelerate assembly and/or distort the capsid shell. We summarize the functional, biochemical, and structural dynamics of Cp, and discuss the therapeutic potential of CAMs based on clinical data. Presently, CAMs appear as a valuable addition but not a substitute for existing therapies. However, as part of rational combination therapies CAMs may bring the ambitious goal of a cure for CHB closer to reality.
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Affiliation(s)
| | | | - Michael Nassal
- Internal Medicine II/Molecular Biology, University Hospital Freiburg, Hugstetter Str. 55, D-79106 Freiburg, Germany; (M.N.); (P.Z.)
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Proteomic Analysis of Nuclear HBV rcDNA Associated Proteins Identifies UV-DDB as a Host Factor Involved in cccDNA Formation. J Virol 2021; 96:e0136021. [PMID: 34705558 DOI: 10.1128/jvi.01360-21] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
Hepatitis B virus (HBV) utilizes host DNA repair mechanisms to convert viral relaxed circular DNA (rcDNA) into a persistent viral genome, the covalently closed circular DNA (cccDNA). To identify said host factors involved in cccDNA formation, we developed an unbiased approach to discover proteins involved in cccDNA formation by precipitating nuclear rcDNA from induced HepAD38 cells and identifying the co-precipitated proteins by mass spectrometry. The DNA damage binding protein 1 (DDB1) surfaced as a hit, coinciding with our previously reported shRNA screen in which shRNA-DDB1 in HepDES19 cells reduced cccDNA production. DDB1 binding to nuclear rcDNA was confirmed in HepAD38 cells via ChIP-qPCR. DDB1 and DNA damage binding protein 2 (DDB2) form the UV-DDB complex and the latter senses DNA damage to initiate the global genome nucleotide excision repair (GG-NER) pathway. To investigate the role of DDB complex in cccDNA formation, DDB2 was knocked out in HepAD38 and HepG2-NTCP cells. In both knockout cell lines, cccDNA formation was stunted significantly, and in HepG2-NTCP-DDB2 knockout cells, downstream indicators of cccDNA such as HBV RNA, HBcAg, and HBeAg were similarly reduced. Knockdown of DDB2 in HBV-infected HepG2-NTCP cells and primary human hepatocytes (PHH) also resulted in cccDNA reduction. Trans-complementation of wild type DDB2 in HepG2-NTCP-DDB2 knockout cells rescued cccDNA formation and its downstream indicators. However, ectopic expression of DDB2 mutants deficient in DNA-binding, DDB1-binding, or ubiquitination failed to rescue cccDNA formation. Our study thus suggests an integral role of UV-DDB, specifically DDB2, in the formation of HBV cccDNA. IMPORTANCE Serving as a key viral factor for chronic hepatitis B virus (HBV) infection, HBV covalently closed circular DNA (cccDNA) is formed in the cell nucleus from viral relaxed circular DNA (rcDNA) by hijacking host DNA repair machinery. Previous studies have identified a handful of host DNA repair factors involved in cccDNA formation through hypothesis-driven research with some help from RNAi screening and/or biochemistry approaches. To enrich the landscape of tools for discovering host factors responsible for rcDNA-to-cccDNA conversion, we developed an rcDNA immunoprecipitation paired mass spectrometry assay, which allowed us to pull down nuclear rcDNA in its transitional state to cccDNA and observe the associated host factors. From this assay we discovered a novel relationship between the UV-DDB complex and cccDNA formation, hence, providing a proof-of-concept for a more direct discovery of novel HBV DNA-host interactions that can be exploited to develop new cccDNA-targeting antivirals.
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Zhang H, Tu T. Approaches to quantifying Hepatitis B Virus covalently closed circular (ccc)DNA. Clin Mol Hepatol 2021; 28:135-149. [PMID: 34674513 PMCID: PMC9013611 DOI: 10.3350/cmh.2021.0283] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/31/2021] [Accepted: 10/21/2021] [Indexed: 11/19/2022] Open
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.
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Affiliation(s)
- Henrik Zhang
- Storr Liver Centre, Westmead Clinical School and Westmead Institute for Medical Research, Faculty of Medicine and Health, The University of Sydney, Westmead, NSW 2145, Australia
| | - Thomas Tu
- Storr Liver Centre, Westmead Clinical School and Westmead Institute for Medical Research, Faculty of Medicine and Health, The University of Sydney, Westmead, NSW 2145, Australia.,Centre for Infectious Diseases and Microbiology, Marie Bashir Institute for Infectious Diseases and Biosecurity, University of Sydney at Westmead Hospital, Westmead NSW 2145, Australia
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Van Damme E, Vanhove J, Severyn B, Verschueren L, Pauwels F. The Hepatitis B Virus Interactome: A Comprehensive Overview. Front Microbiol 2021; 12:724877. [PMID: 34603251 PMCID: PMC8482013 DOI: 10.3389/fmicb.2021.724877] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2021] [Accepted: 08/17/2021] [Indexed: 12/19/2022] Open
Abstract
Despite the availability of a prophylactic vaccine, chronic hepatitis B (CHB) caused by the hepatitis B virus (HBV) is a major health problem affecting an estimated 292 million people globally. Current therapeutic goals are to achieve functional cure characterized by HBsAg seroclearance and the absence of HBV-DNA after treatment cessation. However, at present, functional cure is thought to be complicated due to the presence of covalently closed circular DNA (cccDNA) and integrated HBV-DNA. Even if the episomal cccDNA is silenced or eliminated, it remains unclear how important the high level of HBsAg that is expressed from integrated HBV DNA is for the pathology. To identify therapies that could bring about high rates of functional cure, in-depth knowledge of the virus' biology is imperative to pinpoint mechanisms for novel therapeutic targets. The viral proteins and the episomal cccDNA are considered integral for the control and maintenance of the HBV life cycle and through direct interaction with the host proteome they help create the most optimal environment for the virus whilst avoiding immune detection. New HBV-host protein interactions are continuously being identified. Unfortunately, a compendium of the most recent information is lacking and an interactome is unavailable. This article provides a comprehensive review of the virus-host relationship from viral entry to release, as well as an interactome of cccDNA, HBc, and HBx.
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Affiliation(s)
- Ellen Van Damme
- Janssen Research & Development, Janssen Pharmaceutical Companies, Beerse, Belgium
| | - Jolien Vanhove
- Janssen Research & Development, Janssen Pharmaceutical Companies, Beerse, Belgium.,Early Discovery Biology, Charles River Laboratories, Beerse, Belgium
| | - Bryan Severyn
- Janssen Research & Development, Janssen Pharmaceutical Companies, Springhouse, PA, United States
| | - Lore Verschueren
- Janssen Research & Development, Janssen Pharmaceutical Companies, Beerse, Belgium
| | - Frederik Pauwels
- Janssen Research & Development, Janssen Pharmaceutical Companies, Beerse, Belgium
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40
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Abstract
Chronic hepatitis B virus (HBV) infection is the leading cause of liver cirrhosis and hepatocellular carcinoma, estimated to be globally responsible for ∼800,000 deaths annually. Although effective vaccines are available to prevent new HBV infection, treatment of existing chronic hepatitis B (CHB) is limited, as the current standard-of-care antiviral drugs can only suppress viral replication without achieving cure. In 2016, the World Health Organization called for the elimination of viral hepatitis as a global public health threat by 2030. The United States and other nations are working to meet this ambitious goal by developing strategies to cure CHB, as well as prevent HBV transmission. This review considers recent research progress in understanding HBV pathobiology and development of therapeutics for the cure of CHB, which is necessary for elimination of hepatitis B by 2030.
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Affiliation(s)
- Timothy M Block
- Baruch S. Blumberg Institute, Doylestown, Pennsylvania 18902, USA;
| | - Kyong-Mi Chang
- The Corporal Michael J. Crescenz VA Medical Center and University of Pennsylvania Perelman School of Medicine, Philadelphia, Pennsylvania 19104, USA
| | - Ju-Tao Guo
- Baruch S. Blumberg Institute, Doylestown, Pennsylvania 18902, USA;
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Martinez MG, Boyd A, Combe E, Testoni B, Zoulim F. Covalently closed circular DNA: The ultimate therapeutic target for curing HBV infections. J Hepatol 2021; 75:706-717. [PMID: 34051332 DOI: 10.1016/j.jhep.2021.05.013] [Citation(s) in RCA: 95] [Impact Index Per Article: 23.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/01/2021] [Revised: 05/03/2021] [Accepted: 05/07/2021] [Indexed: 12/16/2022]
Abstract
Current antiviral therapies, such as pegylated interferon-α and nucleos(t)ide analogues, effectively improve the quality of life of patients with chronic hepatitis B. However, they can only control the infection rather than curing infected hepatocytes. Complete HBV cure is hampered by the lack of therapies that can directly affect the viral minichromosome (in the form of covalently closed circular DNA [cccDNA]). Approaches currently under investigation in early clinical trials are aimed at achieving a functional cure, defined as the loss of HBsAg and undetectable HBV DNA levels in serum. However, achieving a complete HBV cure requires therapies that can directly target the cccDNA pool, either via degradation, lethal mutations or functional silencing. In this review, we discuss cutting-edge technologies that could lead to non-cytolytic direct cccDNA targeting and cure of infected hepatocytes.
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Affiliation(s)
| | - Anders Boyd
- Stichting HIV Monitoring, Amsterdam, the Netherlands; Department of Infectious Diseases, Research and Prevention, Public Health Service of Amsterdam, Amsterdam, the Netherlands
| | - Emmanuel Combe
- INSERM U1052, CNRS UMR-5286, Cancer Research Center of Lyon (CRCL), Lyon, 69008, France
| | - Barbara Testoni
- INSERM U1052, CNRS UMR-5286, Cancer Research Center of Lyon (CRCL), Lyon, 69008, France
| | - Fabien Zoulim
- INSERM U1052, CNRS UMR-5286, Cancer Research Center of Lyon (CRCL), Lyon, 69008, France; University of Lyon, Université Claude- Bernard (UCBL), 69008 Lyon, France; Hospices Civils de Lyon (HCL), 69002 Lyon, France.
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Ghosh S, Chakraborty A, Banerjee S. Persistence of Hepatitis B Virus Infection: A Multi-Faceted Player for Hepatocarcinogenesis. Front Microbiol 2021; 12:678537. [PMID: 34526974 PMCID: PMC8435854 DOI: 10.3389/fmicb.2021.678537] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2021] [Accepted: 07/06/2021] [Indexed: 12/14/2022] Open
Abstract
Hepatitis B virus (HBV) infection has a multi-dimensional effect on the host, which not only alters the dynamics of immune response but also persists in the hepatocytes to predispose oncogenic factors. The virus exists in multiple forms of which the nuclear localized covalently closed circular DNA (cccDNA) is the most stable and the primary reason for viral persistence even after clearance of surface antigen and viral DNA. The second reason is the existence of pregenomic RNA (pgRNA) containing virion particles. On the other hand, the integration of the viral genome in the host chromosome also leads to persistent production of viral proteins along with the chromosomal instabilities. The interferon treatment or administration of nucleot(s)ide analogs leads to reduction in the viral DNA load, but the pgRNA and surface antigen clearance are a slow process and complete loss of serological HBsAg is rare. The prolonged exposure of immune cells to the viral antigens, particularly HBs antigen, in the blood circulation results in T-cell exhaustion, which disrupts immune clearance of the virus and virus-infected cells. In addition, it predisposes immune-tolerant microenvironment, which facilitates the tumor progression. Thus cccDNA, pgRNA, and HBsAg along with the viral DNA could be the therapeutic targets in the early disease stages that may improve the quality of life of chronic hepatitis B patients by impeding the progression of the disease toward hepatocellular carcinoma.
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Affiliation(s)
| | | | - Soma Banerjee
- Centre for Liver Research, School of Digestive and Liver Diseases, Institute of Post Graduate Medical Education and Research, Kolkata, India
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Ohsaki E, Suwanmanee Y, Ueda K. Chronic Hepatitis B Treatment Strategies Using Polymerase Inhibitor-Based Combination Therapy. Viruses 2021; 13:v13091691. [PMID: 34578273 PMCID: PMC8473100 DOI: 10.3390/v13091691] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2021] [Revised: 08/19/2021] [Accepted: 08/25/2021] [Indexed: 12/12/2022] Open
Abstract
Viral polymerase is an essential enzyme for the amplification of the viral genome and is one of the major targets of antiviral therapies. However, a serious concern to be solved in hepatitis B virus (HBV) infection is the difficulty of eliminating covalently closed circular (ccc) DNA. More recently, therapeutic strategies targeting various stages of the HBV lifecycle have been attempted. Although cccDNA-targeted therapies are attractive, there are still many problems to be overcome, and the development of novel polymerase inhibitors remains an important issue. Interferons and nucleos(t)ide reverse transcriptase inhibitors (NRTIs) are the only therapeutic options currently available for HBV infection. Many studies have reported that the combination of interferons and NRTI causes the loss of hepatitis B surface antigen (HBsAg), which is suggestive of seroconversion. Although NRTIs do not directly target cccDNA, they can strongly reduce the serum viral DNA load and could suppress the recycling step of cccDNA formation, improve liver fibrosis/cirrhosis, and reduce the risk of hepatocellular carcinoma. Here, we review recent studies on combination therapies using polymerase inhibitors and discuss the future directions of therapeutic strategies for HBV infection.
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Bousali M, Papatheodoridis G, Paraskevis D, Karamitros T. Hepatitis B Virus DNA Integration, Chronic Infections and Hepatocellular Carcinoma. Microorganisms 2021; 9:1787. [PMID: 34442866 PMCID: PMC8398950 DOI: 10.3390/microorganisms9081787] [Citation(s) in RCA: 29] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2021] [Revised: 08/13/2021] [Accepted: 08/18/2021] [Indexed: 12/16/2022] Open
Abstract
Hepatitis B Virus (HBV) is an Old World virus with a high mutation rate, which puts its origins in Africa alongside the origins of Homo sapiens, and is a member of the Hepadnaviridae family that is characterized by a unique viral replication cycle. It targets human hepatocytes and can lead to chronic HBV infection either after acute infection via horizontal transmission usually during infancy or childhood or via maternal-fetal transmission. HBV has been found in ~85% of HBV-related Hepatocellular Carcinomas (HCC), and it can integrate the whole or part of its genome into the host genomic DNA. The molecular mechanisms involved in the HBV DNA integration is not yet clear; thus, multiple models have been described with respect to either the relaxed-circular DNA (rcDNA) or the double-stranded linear DNA (dslDNA) of HBV. Various genes have been found to be affected by HBV DNA integration, including cell-proliferation-related genes, oncogenes and long non-coding RNA genes (lincRNAs). The present review summarizes the advances in the research of HBV DNA integration, focusing on the evolutionary and molecular side of the integration events along with the arising clinical aspects in the light of WHO's commitment to eliminate HBV and viral hepatitis by 2030.
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Affiliation(s)
- Maria Bousali
- Bioinformatics and Applied Genomics Unit, Department of Microbiology, Hellenic Pasteur Institute, 11521 Athens, Greece;
| | - George Papatheodoridis
- Department of Gastroenterology, “Laiko” General Hospital of Athens, Medical School, National and Kapodistrian University of Athens, 11527 Athens, Greece;
| | - Dimitrios Paraskevis
- Department of Hygiene Epidemiology and Medical Statistics, School of Medicine, National and Kapodistrian University of Athens, 15772 Athens, Greece;
| | - Timokratis Karamitros
- Bioinformatics and Applied Genomics Unit, Department of Microbiology, Hellenic Pasteur Institute, 11521 Athens, Greece;
- Laboratory of Medical Microbiology, Department of Microbiology, Hellenic Pasteur Institute, 11521 Athens, Greece
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Abstract
PURPOSE OF REVIEW The current aim in the HBV landscape is to develop therapeutic strategies to achieve a functional cure of infection, characterized by a sustained loss of HBsAg off-treatment. Current treatment options, that is, nucleos(t)ide analogues and IFN are effective at viral suppression but very poor at achieving HBsAg loss. This article is designed to summarize the HBV life cycle in order to review the current treatment strategies and compounds targeting different points of the virus life cycle, which are either in preclinical or clinical phases. RECENT FINDINGS Recently our developed understanding of the HBV life cycle has enabled the development of multiple novel treatment options, all aiming for functional cure. SUMMARY It is likely that combinations of novel treatments will be needed to achieve a functional cure, including those that target the virus itself as well as those that target the immune system.
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46
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Recent developments with advancing gene therapy to treat chronic infection with hepatitis B virus. Curr Opin HIV AIDS 2021; 15:200-207. [PMID: 32141890 DOI: 10.1097/coh.0000000000000623] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
PURPOSE OF REVIEW The available vaccine and therapies against hepatitis B virus (HBV) rarely eliminate chronic infection with the virus. High mortality resulting from complicating cirrhosis and hepatocellular carcinoma makes improving anti-HBV therapy an important priority. Recent advances with using gene therapy to counter HBV have potential and are the focus of this review. RECENT FINDINGS The stable replication-competent HBV intermediate comprising covalently closed circular DNA (cccDNA) is the template for expression of all viral genes. Inactivating cccDNA has thus been a focus of research aimed at achieving cure for HBV infection. Many studies have reported profound inhibition of replication of the virus using silencing and editing techniques. Therapeutic gene silencing with synthetic short interfering RNA is now in clinical trials. Ability to mutate and permanently inactivate cccDNA with engineered gene editors, such as those derived from CRISPR/Cas or TALENs, is particularly appealing but has not yet reached clinical evaluation. SUMMARY Gene silencing and gene editing potentially provide the means to cure HBV infection. However, achieving efficient delivery of therapeutic sequences, ensuring their specificity of action and progress with other antiviral strategies are likely to determine utility of gene therapy for chronic HBV infection.
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47
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Ligat G, Verrier ER, Nassal M, Baumert TF. Hepatitis B virus-host interactions and novel targets for viral cure. Curr Opin Virol 2021; 49:41-51. [PMID: 34029994 PMCID: PMC7613419 DOI: 10.1016/j.coviro.2021.04.009] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2021] [Revised: 04/22/2021] [Accepted: 04/23/2021] [Indexed: 02/06/2023]
Abstract
Chronic infection with HBV is a major cause of advanced liver disease and hepatocellular carcinoma. Nucleos(t)ide analogues effectively control HBV replication but viral cure is rare. Hence treatment has often to be administered for an indefinite duration, increasing the risk for selection of drug resistant virus variants. PEG-interferon-α-based therapies can sometimes cure infection but suffer from a low response rate and severe side-effects. CHB is characterized by the persistence of a nuclear covalently closed circular DNA (cccDNA), which is not targeted by approved drugs. Targeting host factors which contribute to the viral life cycle provides new opportunities for the development of innovative therapeutic strategies aiming at HBV cure. An improved understanding of the host immune system has resulted in new potentially curative candidate approaches. Here, we review the recent advances in understanding HBV-host interactions and highlight how this knowledge contributes to exploiting host-targeting strategies for a viral cure.
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Affiliation(s)
- Gaëtan Ligat
- Université de Strasbourg, F-67000 Strasbourg, France; Inserm, Institut de Recherche sur les Maladies Virales et Hépatiques UMRS 1110, F-67000 Strasbourg, France.
| | - Eloi R Verrier
- Université de Strasbourg, F-67000 Strasbourg, France; Inserm, Institut de Recherche sur les Maladies Virales et Hépatiques UMRS 1110, F-67000 Strasbourg, France.
| | - Michael Nassal
- University Hospital Freiburg, Dept. of Internal Medicine 2/Molecular Biology, D79106 Freiburg, Germany.
| | - Thomas F Baumert
- Université de Strasbourg, F-67000 Strasbourg, France; Inserm, Institut de Recherche sur les Maladies Virales et Hépatiques UMRS 1110, F-67000 Strasbourg, France; Institut Hospitalo-Universitaire, Pôle Hépato-digestif, Nouvel Hôpital Civil, 67000 Strasbourg, France.
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48
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Wei L, Ploss A. Mechanism of Hepatitis B Virus cccDNA Formation. Viruses 2021; 13:v13081463. [PMID: 34452329 PMCID: PMC8402782 DOI: 10.3390/v13081463] [Citation(s) in RCA: 56] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2021] [Revised: 07/14/2021] [Accepted: 07/21/2021] [Indexed: 02/06/2023] Open
Abstract
Hepatitis B virus (HBV) remains a major medical problem affecting at least 257 million chronically infected patients who are at risk of developing serious, frequently fatal liver diseases. HBV is a small, partially double-stranded DNA virus that goes through an intricate replication cycle in its native cellular environment: human hepatocytes. A critical step in the viral life-cycle is the conversion of relaxed circular DNA (rcDNA) into covalently closed circular DNA (cccDNA), the latter being the major template for HBV gene transcription. For this conversion, HBV relies on multiple host factors, as enzymes capable of catalyzing the relevant reactions are not encoded in the viral genome. Combinations of genetic and biochemical approaches have produced findings that provide a more holistic picture of the complex mechanism of HBV cccDNA formation. Here, we review some of these studies that have helped to provide a comprehensive picture of rcDNA to cccDNA conversion. Mechanistic insights into this critical step for HBV persistence hold the key for devising new therapies that will lead not only to viral suppression but to a cure.
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Ko C, Su J, Festag J, Bester R, Kosinska AD, Protzer U. Intramolecular recombination enables the formation of hepatitis B virus (HBV) cccDNA in mice after HBV genome transfer using recombinant AAV vectors. Antiviral Res 2021; 194:105140. [PMID: 34284057 DOI: 10.1016/j.antiviral.2021.105140] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2021] [Revised: 07/09/2021] [Accepted: 07/12/2021] [Indexed: 01/11/2023]
Abstract
The mouse is not a natural host of hepatitis B virus (HBV) infection and - despite engraftment of hepatocytes with the HBV receptor - does not support formation of HBV covalently closed circular (ccc) DNA serving as a template for viral transcription and permitting persistent infection. In a recent study, cccDNA formation in mouse hepatocytes has been described following an HBV genome delivery by a recombinant, adeno-associated virus vector (rAAV) (Lucifora et al., 2017). The integrity of HBV cccDNA, its origin and functionality, however, remained open. In this study, we investigated the identity, origin, and functionality of cccDNA established in mice infected with rAAV carrying 1.3-fold overlength HBV genomes. We show that replication of HBV genotypes A, B, C and D can be initiated in mouse livers, and that cccDNA derived from all genotypes is detected. Restriction enzyme and exonuclease digestion as well as sequencing analysis of cccDNA amplicons revealed authentic HBV cccDNA without any detectable alteration compared to cccDNA established after HBV infection of human liver cells. Mouse livers transduced with a core protein-deficient HBV using rAAV still supported cccDNA formation demonstrating that the genesis of cccDNA was independent of HBV replication. When mice were infected with an rAAV-HBV1.3 carrying premature stop codons in the 5' but not in the 3' core protein open reading frame, the stop codon was partially replaced by the wild-type sequence. This strongly indicated that intramolecular recombination, based on >900 identical base pairs residing at the both ends of the HBV1.3 transgene was the origin of cccDNA formation. Accordingly, we observed a constant loss of cccDNA molecules from mouse livers over time, while HBeAg levels increased over the first two weeks after rAAV-HBV1.3 infection and remained constant thereafter, suggesting a minor contribution of the cccDNA molecules formed to viral transcription and protein expression. In summary, our results provide strong evidence that intramolecular recombination of an overlength, linear HBV genome, but not HBV genome recycling, enables cccDNA formation in rAAV-HBV mouse models.
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Affiliation(s)
- Chunkyu Ko
- Institute of Virology, Technical University of Munich/Helmholtz Zentrum München, Munich, Germany; Infectious Diseases Therapeutic Research Center, Therapeutics & Biotechnology Division, Korea Research Institute of Chemical Technology, Daejeon, Republic of Korea
| | - Jinpeng Su
- Institute of Virology, Technical University of Munich/Helmholtz Zentrum München, Munich, Germany
| | - Julia Festag
- Institute of Virology, Technical University of Munich/Helmholtz Zentrum München, Munich, Germany
| | - Romina Bester
- Institute of Virology, Technical University of Munich/Helmholtz Zentrum München, Munich, Germany
| | - Anna D Kosinska
- Institute of Virology, Technical University of Munich/Helmholtz Zentrum München, Munich, Germany; German Center for Infection Research (DZIF), Munich partner site, Munich, Germany
| | - Ulrike Protzer
- Institute of Virology, Technical University of Munich/Helmholtz Zentrum München, Munich, Germany; German Center for Infection Research (DZIF), Munich partner site, Munich, Germany.
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50
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Qu B, Brown RJP. Strategies to Inhibit Hepatitis B Virus at the Transcript Level. Viruses 2021; 13:v13071327. [PMID: 34372533 PMCID: PMC8310268 DOI: 10.3390/v13071327] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2021] [Revised: 07/02/2021] [Accepted: 07/06/2021] [Indexed: 12/11/2022] Open
Abstract
Approximately 240 million people are chronically infected with hepatitis B virus (HBV), despite four decades of effective HBV vaccination. During chronic infection, HBV forms two distinct templates responsible for viral transcription: (1) episomal covalently closed circular (ccc)DNA and (2) host genome-integrated viral templates. Multiple ubiquitous and liver-specific transcription factors are recruited onto these templates and modulate viral gene transcription. This review details the latest developments in antivirals that inhibit HBV gene transcription or destabilize viral transcripts. Notably, nuclear receptor agonists exhibit potent inhibition of viral gene transcription from cccDNA. Small molecule inhibitors repress HBV X protein-mediated transcription from cccDNA, while small interfering RNAs and single-stranded oligonucleotides result in transcript degradation from both cccDNA and integrated templates. These antivirals mediate their effects by reducing viral transcripts abundance, some leading to a loss of surface antigen expression, and they can potentially be added to the arsenal of drugs with demonstrable anti-HBV activity. Thus, these candidates deserve special attention for future repurposing or further development as anti-HBV therapeutics.
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Affiliation(s)
- Bingqian Qu
- Division of Veterinary Medicine, Paul Ehrlich Institute, 63225 Langen, Germany
- European Virus Bioinformatics Center, 07743 Jena, Germany
- Correspondence: (B.Q.); (R.J.P.B.)
| | - Richard J. P. Brown
- Division of Veterinary Medicine, Paul Ehrlich Institute, 63225 Langen, Germany
- Correspondence: (B.Q.); (R.J.P.B.)
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