51
|
Abstract
The hepatitis B virus (HBV) is a member of the Hepadnaviridae family, which includes small DNA enveloped viruses that infect primates, rodents, and birds and is the causative factor of chronic hepatitis B. A common feature of all these viruses is their great specificity by species and cell type, as well as a peculiar genomic and replication organization similar to that of retroviruses. The HBV virion consists of an external lipid envelope and an internal icosahedral protein capsid containing the viral genome and a DNA polymerase, which also functions as a reverse transcriptase.
Collapse
Affiliation(s)
- Alessandro Loglio
- Division of Gastroenterology and Hepatology, Foundation IRCCS Ca' Granda Ospedale Maggiore Policlinico, Via F. Sforza 35, 20122 Milan, Italy
| | - Mauro Viganò
- Hepatology Division, San Giuseppe Hospital Multimedica Spa, Via San Vittore 12, 20123 Milan, Italy
| | - Pietro Lampertico
- Division of Gastroenterology and Hepatology, Foundation IRCCS Ca' Granda Ospedale Maggiore Policlinico, Via F. Sforza 35, 20122 Milan, Italy; Department of Pathophysiology and Transplantation, CRC "A. M. and A. Migliavacca" Center for Liver Disease, University of Milan, Via F. Sforza 35, Milan 20122, Italy.
| |
Collapse
|
52
|
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: 3.3] [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.
Collapse
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
| |
Collapse
|
53
|
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: 6.0] [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.
Collapse
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
| |
Collapse
|
54
|
Ye J, Chen J. Interferon and Hepatitis B: Current and Future Perspectives. Front Immunol 2021; 12:733364. [PMID: 34557195 PMCID: PMC8452902 DOI: 10.3389/fimmu.2021.733364] [Citation(s) in RCA: 71] [Impact Index Per Article: 23.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2021] [Accepted: 08/17/2021] [Indexed: 12/12/2022] Open
Abstract
Chronic hepatitis B virus (HBV) infection remains a major health burden worldwide for which there is still no effective curative treatment. Interferon (IFN) consists of a group of cytokines with antiviral activity and immunoregulatory and antitumor effects, that play crucial roles in both innate and adaptive immune responses. IFN-α and its pegylated form have been used for over thirty years to treat chronic hepatitis B (CHB) with advantages of finite treatment duration and sustained virologic response, however, the efficacy is limited and side effects are common. Here, we summarize the status and unique advantages of IFN therapy against CHB, review the mechanisms of IFN-α action and factors affecting IFN response, and discuss the possible improvement of IFN-based therapy and the rationale of combinations with other antiviral agents in seeking an HBV cure.
Collapse
Affiliation(s)
- Jianyu Ye
- Key Laboratory of Medical Molecular Virology (MOE/NHC/CAMS), School of Basic Medical Sciences, Shanghai Medical College, Fudan University, Shanghai, China
| | - Jieliang Chen
- Key Laboratory of Medical Molecular Virology (MOE/NHC/CAMS), School of Basic Medical Sciences, Shanghai Medical College, Fudan University, Shanghai, China.,Research Unit of Cure of Chronic Hepatitis B Virus Infection, Chinese Academy of Medical Sciences, Shanghai, China
| |
Collapse
|
55
|
Rydell GE, Prakash K, Larsson SB, Skoglund C, Ringlander J, Andersson M, Castedal M, Norder H, Lindh M. Quantification of viral RNA in multiple pieces of explant liver tissue shows distinct focal differences of hepatitis B infection. J Infect Dis 2021; 226:1036-1040. [PMID: 34534318 PMCID: PMC9492311 DOI: 10.1093/infdis/jiab469] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2021] [Accepted: 09/16/2021] [Indexed: 11/20/2022] Open
Abstract
Hepatitis B virus (HBV) DNA and RNA were quantified by digital PCR assays in 20–30 tissue pieces from each of 4 liver explants with cirrhosis caused by HBV. The within-patient variability of HBV RNA levels between pieces was up to a 1000-fold. Core RNA and S RNA levels were similar and correlated strongly when replication was high, supporting that transcription was from covalently closed circular DNA (cccDNA). By contrast, enhanced expression of S RNA relative to cccDNA and core RNA in patients with medium-high or low replication supports that HBV surface antigen (HBsAg) can be expressed mainly from integrated HBV DNA in such patients.
Collapse
Affiliation(s)
- Gustaf E Rydell
- Department of Infectious Diseases, Institute of Biomedicine, Sahlgrenska Academy, University of Gothenburg, SE-413 46 Gothenburg, Sweden
| | - Kasthuri Prakash
- Department of Infectious Diseases, Institute of Biomedicine, Sahlgrenska Academy, University of Gothenburg, SE-413 46 Gothenburg, Sweden
| | - Simon B Larsson
- Department of Infectious Diseases, Institute of Biomedicine, Sahlgrenska Academy, University of Gothenburg, SE-413 46 Gothenburg, Sweden
| | - Catarina Skoglund
- The Transplant Institute, Department of Surgery, Sahlgrenska University Hospital, and The Institute of Clinical Sciences, Sahlgrenska Academy, University of Gothenburg, 413 45 Gothenburg, Sweden
| | - Johan Ringlander
- Department of Infectious Diseases, Institute of Biomedicine, Sahlgrenska Academy, University of Gothenburg, SE-413 46 Gothenburg, Sweden
| | - Maria Andersson
- Department of Infectious Diseases, Institute of Biomedicine, Sahlgrenska Academy, University of Gothenburg, SE-413 46 Gothenburg, Sweden
| | - Maria Castedal
- The Transplant Institute, Department of Surgery, Sahlgrenska University Hospital, and The Institute of Clinical Sciences, Sahlgrenska Academy, University of Gothenburg, 413 45 Gothenburg, Sweden
| | - Heléne Norder
- Department of Infectious Diseases, Institute of Biomedicine, Sahlgrenska Academy, University of Gothenburg, SE-413 46 Gothenburg, Sweden
| | - Magnus Lindh
- Department of Infectious Diseases, Institute of Biomedicine, Sahlgrenska Academy, University of Gothenburg, SE-413 46 Gothenburg, Sweden
| |
Collapse
|
56
|
Zhu M, Liang Z, Pan J, Zhang X, Xue R, Cao G, Hu X, Gong C. Hepatocellular carcinoma progression mediated by hepatitis B virus-encoded circRNA HBV_circ_1 through interaction with CDK1. MOLECULAR THERAPY-NUCLEIC ACIDS 2021; 25:668-682. [PMID: 34589285 PMCID: PMC8463320 DOI: 10.1016/j.omtn.2021.08.011] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/18/2020] [Accepted: 08/10/2021] [Indexed: 02/07/2023]
Abstract
Hepatitis B virus (HBV) produces circular RNA (circRNA), whose functions have not yet been clearly elucidated. In this study, a novel circRNA HBV_circ_1 produced by HBV was identified in HBV-positive HepG2.2.15 cells and HBV-related hepatocellular carcinoma (HCC) tissue (HCCT). Microarray analysis of 68 HCCT samples showed that HBV_circ_1 abundance was significantly higher than that in paracancerous tissues. In addition, survival rate of HBV_circ_1-positive patients was significantly lower compared with HBV_circ_1-negative patients. Transient expression indicated that HBV_circ_1 enhanced cell proliferation, migration, and invasion and inhibited apoptosis in vitro. Furthermore, ectopical HBV_circ_1 expression increased tumor size in vivo. HBV_circ_1 was confirmed to interact with cyclin-dependent kinase 1 (CDK1) to regulate cell proliferation. These results suggest that HCC progression may be promoted by interaction of HBV_circ_1 with CDK1. Our data not only showed a novel clue to understand carcinogenesis and progress of HBV-related HCC but also provided a new target for the development of therapeutic drugs.
Collapse
Affiliation(s)
- Min Zhu
- School of Biology & Basic Medical Science, Soochow University, Suzhou 215123, China
| | - Zi Liang
- School of Biology & Basic Medical Science, Soochow University, Suzhou 215123, China
| | - Jun Pan
- School of Biology & Basic Medical Science, Soochow University, Suzhou 215123, China
| | - Xing Zhang
- School of Biology & Basic Medical Science, Soochow University, Suzhou 215123, China
| | - Renyu Xue
- School of Biology & Basic Medical Science, Soochow University, Suzhou 215123, China
| | - Guangli Cao
- School of Biology & Basic Medical Science, Soochow University, Suzhou 215123, China
| | - Xiaolong Hu
- School of Biology & Basic Medical Science, Soochow University, Suzhou 215123, China
| | - Chengliang Gong
- School of Biology & Basic Medical Science, Soochow University, Suzhou 215123, China
| |
Collapse
|
57
|
Crosstalk between Environmental Inflammatory Stimuli and Non-Coding RNA in Cancer Occurrence and Development. Cancers (Basel) 2021; 13:cancers13174436. [PMID: 34503246 PMCID: PMC8430834 DOI: 10.3390/cancers13174436] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2021] [Revised: 08/20/2021] [Accepted: 08/31/2021] [Indexed: 12/12/2022] Open
Abstract
Simple Summary Increasing evidence has indicated that chronic inflammatory processes have an influence on tumor occurrence and all stages of tumor development. A dramatic increase of studies into non-coding RNAs (ncRNAs) biology has shown that ncRNAs act as oncogenic drivers and tumor suppressors in various inflammation-induced cancers. Thus, this complex network of inflammation-associated cancers and ncRNAs offers targets for prevention from the malignant transformation from inflammation and treatment of malignant diseases. Abstract There is a clear relationship between inflammatory response and different stages of tumor development. Common inflammation-related carcinogens include viruses, bacteria, and environmental mutagens, such as air pollutants, toxic metals, and ultraviolet light. The expression pattern of ncRNA changes in a variety of disease conditions, including inflammation and cancer. Non-coding RNAs (ncRNAs) have a causative role in enhancing inflammatory stimulation and evading immune responses, which are particularly important in persistent pathogen infection and inflammation-to-cancer transformation. In this review, we investigated the mechanism of ncRNA expression imbalance in inflammation-related cancers. A better understanding of the function of inflammation-associated ncRNAs may help to reveal the potential of ncRNAs as a new therapeutic strategy.
Collapse
|
58
|
Medas R, Liberal R, Macedo G. Discontinuation of antiviral therapy in chronic hepatitis B patients. World J Clin Cases 2021; 9:6979-6986. [PMID: 34540953 PMCID: PMC8409197 DOI: 10.12998/wjcc.v9.i24.6979] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/29/2021] [Revised: 05/29/2021] [Accepted: 07/02/2021] [Indexed: 02/06/2023] Open
Abstract
Nucleos(t)ide analogs (NUC) are the first-line therapy for patients with chronic hepatitis B (CHB) recommended by most current guidelines. NUC therapy decreases progression of liver disease, reduces the risk of liver-related complications, and improves the quality of life of patients with CHB. Although indefinite or long-term NUC therapy is usually recommended, this strategy raises several concerns, such as side-effects, adherence, costs, and patient willingness to stop therapy. Recent data showed the feasibility, efficacy, and safety of stopping antiviral therapy in carefully selected CHB patients, leading to its incorporation in international guidelines. Patients who discontinue NUC have a higher likelihood of hepatitis B surface antigen (HBsAg) loss compared to patients who continue on therapy. Recommendations pertaining endpoints allowing safety discontinuation of NUC therapy differ among international guidelines. For hepatitis B e antigen (HBeAg)-positive patients, durable HBeAg seroconversion is considered an acceptable treatment endpoint. For HBeAg-negative patients, some guidelines propose undetectability hepatitis B virus DNA for at least 2 or 3 years, while others consider HBsAg loss as the only acceptable endpoint. CHB patients who stop therapy should remain under strict clinical and laboratorial follow-up protocols to detect and manage relapses in a timely manner. No reliable predictor of relapse has been consistently identified to date, although quantitative HBsAg has been increasingly studied as a reliable biomarker to predict safe NUC discontinuation.
Collapse
Affiliation(s)
- Renato Medas
- Department of Gastroenterology and Hepatology, Centro Hospitalar Universitário de São João, Porto 4200-319, Portugal
| | - Rodrigo Liberal
- Department of Gastroenterology and Hepatology, Centro Hospitalar Universitário de São João, Porto 4200-319, Portugal
| | - Guilherme Macedo
- Department of Gastroenterology and Hepatology, Centro Hospitalar Universitário de São João, Porto 4200-319, Portugal
| |
Collapse
|
59
|
Yuan H, Zhao L, Yuan Y, Yun H, Zheng W, Geng Y, Yang G, Wang Y, Zhao M, Zhang X. HBx represses WDR77 to enhance HBV replication by DDB1-mediated WDR77 degradation in the liver. Am J Cancer Res 2021; 11:8362-8378. [PMID: 34373747 PMCID: PMC8343998 DOI: 10.7150/thno.57531] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2020] [Accepted: 07/06/2021] [Indexed: 12/18/2022] Open
Abstract
Rationale: Hepatitis B x protein (HBx) is required to initiate and maintain the replication of hepatitis B virus (HBV). Protein arginine methyltransferases 5 (PRMT5) negatively regulates HBV transcription. WD repeat domain 77 protein (WDR77) greatly enhances the methyltransferase activity of PRMT5. However, the role of WDR77 in the modulation of cccDNA transcription and HBV replication is poorly understood. In this study, we investigated the mechanism by which HBx modulated HBV replication involving WDR77 in the liver. Methods: A human liver-chimeric mouse model was established. Immunohistochemistry (IHC) staining, Western blot analysis, Southern blot analysis, Northern blot analysis, immunofluorescence assays, ELISA, RT-qPCR, CoIP assays, and ChIP assays were performed in human liver-chimeric mouse model, primary human hepatocytes (PHHs), HepG2-NTCP, dHepaRG and HepG2 cell lines. Results: HBV infection and HBx expression remarkably reduced the protein levels of WDR77 in human liver-chimeric mice and HepG2-NTCP cells. WDR77 restricted cccDNA transcription and HBV replication in PHHs and HepG2-NTCP cells. Mechanically, WDR77 enhanced PRMT5-triggered symmetric dimethylation of arginine 3 on H4 (H4R3me2s) on the cccDNA minichromosome to control cccDNA transcription. HBx drove the cellular DDB1-containing E3 ubiquitin ligase to degrade WDR77 through recruiting WDR77, leading to the disability of methyltransferase activity of PRMT5. Thus, HBx promoted HBV replication by driving a positive feedback loop of HBx-DDB1/WDR77/PRMT5/H4R3me2s/cccDNA/HBV/HBx in the liver. Conclusions: HBx attenuates the WDR77-mediated HBV repression by driving DDB1-induced WDR77 degradation in the liver. Our finding provides new insights into the mechanism by which HBx enhances HBV replication in the liver.
Collapse
|
60
|
Smith T, Singh P, Chmielewski KO, Bloom K, Cathomen T, Arbuthnot P, Ely A. Improved Specificity and Safety of Anti-Hepatitis B Virus TALENs Using Obligate Heterodimeric FokI Nuclease Domains. Viruses 2021; 13:v13071344. [PMID: 34372550 PMCID: PMC8310341 DOI: 10.3390/v13071344] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2021] [Accepted: 07/02/2021] [Indexed: 01/04/2023] Open
Abstract
Persistent hepatitis B virus (HBV) infection remains a serious medical problem worldwide, with an estimated global burden of 257 million carriers. Prophylactic and therapeutic interventions, in the form of a vaccine, immunomodulators, and nucleotide and nucleoside analogs, are available. Vaccination, however, offers no therapeutic benefit to chronic sufferers and has had a limited impact on infection rates. Although immunomodulators and nucleotide and nucleoside analogs have been licensed for treatment of chronic HBV, cure rates remain low. Transcription activator-like effector nucleases (TALENs) designed to bind and cleave viral DNA offer a novel therapeutic approach. Importantly, TALENs can target covalently closed circular DNA (cccDNA) directly with the potential of permanently disabling this important viral replicative intermediate. Potential off-target cleavage by engineered nucleases leading to toxicity presents a limitation of this technology. To address this, in the context of HBV gene therapy, existing TALENs targeting the viral core and surface open reading frames were modified with second- and third-generation FokI nuclease domains. As obligate heterodimers these TALENs prevent target cleavage as a result of FokI homodimerization. Second-generation obligate heterodimeric TALENs were as effective at silencing viral gene expression as first-generation counterparts and demonstrated an improved specificity in a mouse model of HBV replication.
Collapse
Affiliation(s)
- Tiffany Smith
- Wits/SAMRC Antiviral Gene Therapy Research Unit, School of Pathology, Faculty of Health Sciences, University of the Witwatersrand, Parktown 2193, South Africa; (T.S.); (P.S.); (K.B.); (P.A.)
| | - Prashika Singh
- Wits/SAMRC Antiviral Gene Therapy Research Unit, School of Pathology, Faculty of Health Sciences, University of the Witwatersrand, Parktown 2193, South Africa; (T.S.); (P.S.); (K.B.); (P.A.)
| | - Kay Ole Chmielewski
- Institute for Transfusion Medicine and Gene Therapy, Medical Center-University of Freiburg & Medical Faculty, University of Freiburg, 79106 Freiburg, Germany; (K.O.C.); (T.C.)
| | - Kristie Bloom
- Wits/SAMRC Antiviral Gene Therapy Research Unit, School of Pathology, Faculty of Health Sciences, University of the Witwatersrand, Parktown 2193, South Africa; (T.S.); (P.S.); (K.B.); (P.A.)
| | - Toni Cathomen
- Institute for Transfusion Medicine and Gene Therapy, Medical Center-University of Freiburg & Medical Faculty, University of Freiburg, 79106 Freiburg, Germany; (K.O.C.); (T.C.)
| | - Patrick Arbuthnot
- Wits/SAMRC Antiviral Gene Therapy Research Unit, School of Pathology, Faculty of Health Sciences, University of the Witwatersrand, Parktown 2193, South Africa; (T.S.); (P.S.); (K.B.); (P.A.)
| | - Abdullah Ely
- Wits/SAMRC Antiviral Gene Therapy Research Unit, School of Pathology, Faculty of Health Sciences, University of the Witwatersrand, Parktown 2193, South Africa; (T.S.); (P.S.); (K.B.); (P.A.)
- Correspondence: ; Tel.: +27-(0)11-717-2561
| |
Collapse
|
61
|
Song H, Xu F, Pang X, Xiao Q, Wei Q, Lei B, Li X, Fan X, Tan G. STAT3-Dependent Gene TRIM5γ Interacts With HBx Through a Zinc Binding Site on the BBox Domain. Front Microbiol 2021; 12:663534. [PMID: 34276596 PMCID: PMC8283784 DOI: 10.3389/fmicb.2021.663534] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2021] [Accepted: 06/11/2021] [Indexed: 12/05/2022] Open
Abstract
Owing to its broad-spectrum antivirus activities, interferon (IFN) is an important alternative agent for use in the treatment of hepatitis B virus (HBV)-infected patients; however, the mechanism involved in the inhibition of HBV infection and replication by IFN remains unclear. We previously reported that the induction of TRIM5γ is important in the IFN treatment of HBV patients as it promotes the degradation of the HBx protein, while the manner in which TRIM5γ is induced by IFN and how TRIM5γ interacts with HBx remain unestablished until date. Our present findings confirmed the TRIM5γ-HBx-DDB1 interactions in the HBV-infected Primary human hepatocytes (PHH), and we further found that STAT3, and not STAT1, was responsible for the induction of TRIM5γ upon IFN stimulation and that the zinc binding site His123 on the BBOX domain was a decisive site in the interaction between TRIM5γ BBOX and HBx. In addition, based on the BBOX domain, we detected a 7-amino acid peptide with the potential of promoting HBx degradation and inhibiting HBV replication. On the other hand, we noted that the TRIM5γ expression was inhibited by HBV in chronically HBV infected patients. Thus, our study identified the crucial role of STAT3 in the induction of TRIM5γ, as well as proposed a 7-amino acid, small peptide as a potential candidate for the development of therapeutic agents targeting HBx.
Collapse
Affiliation(s)
- Hongxiao Song
- Department of Immunology, Institute of Translational Medicine, The First Hospital of Jilin University, Changchun, China
| | - Fengchao Xu
- Department of Immunology, Institute of Translational Medicine, The First Hospital of Jilin University, Changchun, China
| | - Xiaoli Pang
- Department of Pediatric Gastroenterology, The First Hospital of Jilin University, Changchun, China
| | - Qingfei Xiao
- Department of Nephrology, The First Hospital of Jilin University, Changchun, China
| | - Qi Wei
- Department of Anesthesia, The First Hospital of Jilin University, Changchun, China
| | - Bingxin Lei
- Department of Anesthesia, The First Hospital of Jilin University, Changchun, China
| | - Xiaolu Li
- Department of Nephrology, The First Hospital of Jilin University, Changchun, China
| | - Xixi Fan
- Department of Clinical Specialty of Integrated Traditional Chinese and Western Medicine, Changchun University of Chinese Medicine, Changchun, China
| | - Guangyun Tan
- Department of Immunology, Institute of Translational Medicine, The First Hospital of Jilin University, Changchun, China
| |
Collapse
|
62
|
Singh P, Kairuz D, Arbuthnot P, Bloom K. Silencing hepatitis B virus covalently closed circular DNA: The potential of an epigenetic therapy approach. World J Gastroenterol 2021; 27:3182-3207. [PMID: 34163105 PMCID: PMC8218364 DOI: 10.3748/wjg.v27.i23.3182] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/29/2021] [Revised: 03/23/2021] [Accepted: 05/07/2021] [Indexed: 02/06/2023] Open
Abstract
Global prophylactic vaccination programmes have helped to curb new hepatitis B virus (HBV) infections. However, it is estimated that nearly 300 million people are chronically infected and have a high risk of developing hepatocellular carcinoma. As such, HBV remains a serious health priority and the development of novel curative therapeutics is urgently needed. Chronic HBV infection has been attributed to the persistence of the covalently closed circular DNA (cccDNA) which establishes itself as a minichromosome in the nucleus of hepatocytes. As the viral transcription intermediate, the cccDNA is responsible for producing new virions and perpetuating infection. HBV is dependent on various host factors for cccDNA formation and the minichromosome is amenable to epigenetic modifications. Two HBV proteins, X (HBx) and core (HBc) promote viral replication by modulating the cccDNA epigenome and regulating host cell responses. This includes viral and host gene expression, chromatin remodeling, DNA methylation, the antiviral immune response, apoptosis, and ubiquitination. Elimination of the cccDNA minichromosome would result in a sterilizing cure; however, this may be difficult to achieve. Epigenetic therapies could permanently silence the cccDNA minichromosome and promote a functional cure. This review explores the cccDNA epigenome, how host and viral factors influence transcription, and the recent epigenetic therapies and epigenome engineering approaches that have been described.
Collapse
Affiliation(s)
- Prashika Singh
- Wits/SAMRC Antiviral Gene Therapy Research Unit, School of Pathology, University of the Witwatersrand, Johannesburg 2050, Gauteng, South Africa
| | - Dylan Kairuz
- Wits/SAMRC Antiviral Gene Therapy Research Unit, School of Pathology, University of the Witwatersrand, Johannesburg 2050, Gauteng, South Africa
| | - Patrick Arbuthnot
- Wits/SAMRC Antiviral Gene Therapy Research Unit, School of Pathology, University of the Witwatersrand, Johannesburg 2050, Gauteng, South Africa
| | - Kristie Bloom
- Wits/SAMRC Antiviral Gene Therapy Research Unit, School of Pathology, University of the Witwatersrand, Johannesburg 2050, Gauteng, South Africa
| |
Collapse
|
63
|
Vaillant A. HBsAg, Subviral Particles, and Their Clearance in Establishing a Functional Cure of Chronic Hepatitis B Virus Infection. ACS Infect Dis 2021; 7:1351-1368. [PMID: 33302622 DOI: 10.1021/acsinfecdis.0c00638] [Citation(s) in RCA: 24] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
In diverse viral infections, the production of excess viral particles containing only viral glycoproteins (subviral particles or SVP) is commonly observed and is a commonly evolved mechanism for immune evasion. In hepatitis B virus (HBV) infection, spherical particles contain the hepatitis B surface antigen, outnumber infectious virus 10 000-100 000 to 1, and have diverse inhibitory effects on the innate and adaptive immune response, playing a major role in the chronic nature of HBV infection. The current goal of therapies in development for HBV infection is a clinical outcome called functional cure, which signals a persistent and effective immune control of the infection. Although removal of spherical SVP (and the HBsAg they carry) is an important milestone in achieving functional cure, this outcome is rarely achieved with current therapies due to distinct mechanisms for assembly, secretion, and persistence of SVP, which are poorly targeted by direct acting antivirals or immunotherapies. In this Review, the current understanding of the distinct mechanisms involved in the production and persistence of spherical SVP in chronic HBV infection and their immunoinhibitory activity will be reviewed as well as current therapies in development with the goal of clearing spherical SVP and achieving functional cure.
Collapse
Affiliation(s)
- Andrew Vaillant
- Replicor Inc., 6100 Royalmount Avenue, Montreal, Quebec H8Y 3E6, Canada
| |
Collapse
|
64
|
Assessment of hepatitis B virus pregenomic RNA in high and low viremic chronic hepatitis B patients. Clin Exp Hepatol 2021; 7:85-92. [PMID: 34027120 PMCID: PMC8122096 DOI: 10.5114/ceh.2021.104472] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/18/2020] [Accepted: 12/16/2020] [Indexed: 11/17/2022] Open
Abstract
Aim of the study Intrahepatic covalently closed circular DNA (cccDNA) is the main cause of hepatitis B virus (HBV) persistence. Therefore, a noninvasive serum biomarker that can reflect intrahepatic cccDNA is required for evaluation of HBV virological, biochemical activity and therapeutic response. Aim of the study was to assess serum hepatitis B pregenomic RNA in low viremia patients (HBV DNA < 2000 IU/ml) and high viremia (HBV DNA > 2000 IU/ml). Material and methods This study was carried out on two groups of chronic hepatitis B patients: group A - 40 patients with low viremia (HBV DNA < 2000 IU/ml); group B - 40 patients with high viremia (HBV DNA > 2000 IU/ml when diagnosed). They were assessed before treatment and after 6 months of treatment (entecavir 0.5 mg/24 h). Serum HBV pregenomic RNA was quantified using RT-PCR. Results Pregenomic RNA (pgRNA) was significantly lower in group A than in group B (before treatment). Moreover, it was significantly lower after 6 months of treatment than before treatment in group B. A significant positive correlation was observed between pgRNA and HBV DNA in groups A and B (before treatment); however, after 6 months of treatment of group B patients, although 35 patients had undetectable HBV DNA, they showed detectable levels of serum pgRNA and pgRNA > 4000 IU/ml was associated with virological and biochemical activity. Conclusions Serum HBV pregenomic RNA might be a promising marker for assessment of HBV virological, biochemical activity and evaluating therapeutic responses.
Collapse
|
65
|
Transaminase Elevations during Treatment of Chronic Hepatitis B Infection: Safety Considerations and Role in Achieving Functional Cure. Viruses 2021; 13:v13050745. [PMID: 33922828 PMCID: PMC8146791 DOI: 10.3390/v13050745] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2021] [Revised: 04/20/2021] [Accepted: 04/22/2021] [Indexed: 11/17/2022] Open
Abstract
While current therapies for chronic HBV infection work well to control viremia and stop the progression of liver disease, the preferred outcome of therapy is the restoration of immune control of HBV infection, allowing therapy to be removed while maintaining effective suppression of infection and reversal of liver damage. This “functional cure” of chronic HBV infection is characterized by the absence of detectable viremia (HBV DNA) and antigenemia (HBsAg) and normal liver function and is the goal of new therapies in development. Functional cure requires removal of the ability of infected cells in the liver to produce the hepatitis B surface antigen. The increased observation of transaminase elevations with new therapies makes understanding the safety and therapeutic impact of these flares an increasingly important issue. This review examines the factors driving the appearance of transaminase elevations during therapy of chronic HBV infection and the interplay of these factors in assessing the safety and beneficial nature of these flares.
Collapse
|
66
|
Wang G, Guan J, Khan NU, Li G, Shao J, Zhou Q, Xu L, Huang C, Deng J, Zhu H, Chen Z. Potential capacity of interferon-α to eliminate covalently closed circular DNA (cccDNA) in hepatocytes infected with hepatitis B virus. Gut Pathog 2021; 13:22. [PMID: 33845868 PMCID: PMC8040234 DOI: 10.1186/s13099-021-00421-9] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/08/2021] [Accepted: 04/01/2021] [Indexed: 12/14/2022] Open
Abstract
Interferon-alpha (IFN-α) and nucleot(s)ide analogs (NAs) are first-line drugs for the treatment of chronic hepatitis B virus (HBV) infections. Generally, NAs target the reverse transcription of HBV pregenomic RNA, but they cannot eliminate covalently-closed-circular DNA (cccDNA). Although effective treatment with NAs can dramatically decrease HBV proteins and DNA loads, and even promote serological conversion, cccDNA persists in the nucleus of hepatocytes due to the lack of effective anti-cccDNA drugs. Of the medications currently available, only IFN-α can potentially target cccDNA. However, the clinical effects of eradicating cccDNA using IFN-α in the hepatocytes of patients with HBV are not proficient as well as expected and are not well understood. Herein, we review the anti-HBV mechanisms of IFN-α involving cccDNA modification as the most promising approaches to cure HBV infection. We expect to find indications of promising areas of research that require further study to eliminate cccDNA of HBV in patients.
Collapse
Affiliation(s)
- Gang Wang
- 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 School of Medicine, 79 Qingchun Road, Hangzhou, 310003, Zhejiang, China
| | - Jun Guan
- 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 School of Medicine, 79 Qingchun Road, Hangzhou, 310003, Zhejiang, China
| | - Nazif U Khan
- 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 School of Medicine, 79 Qingchun Road, Hangzhou, 310003, Zhejiang, China
| | - Guojun Li
- Institute for Hepatology, Shenzhen Third People's Hospital, National Clinical Research Center for Infectious Disease, Shenzhen, 518112, Guangdong, China.,The Second Affiliated Hospital, School of Medicine, Southern University of Science and Technology, 518112, Shenzhen, China
| | - Junwei Shao
- 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 School of Medicine, 79 Qingchun Road, Hangzhou, 310003, Zhejiang, China
| | - Qihui Zhou
- 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 School of Medicine, 79 Qingchun Road, Hangzhou, 310003, Zhejiang, China
| | - Lichen Xu
- 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 School of Medicine, 79 Qingchun Road, Hangzhou, 310003, Zhejiang, China
| | - Chunhong Huang
- 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 School of Medicine, 79 Qingchun Road, Hangzhou, 310003, Zhejiang, China
| | - Jingwen Deng
- 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 School of Medicine, 79 Qingchun Road, Hangzhou, 310003, Zhejiang, China
| | - Haihong Zhu
- 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 School of Medicine, 79 Qingchun Road, Hangzhou, 310003, Zhejiang, 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 School of Medicine, 79 Qingchun Road, Hangzhou, 310003, Zhejiang, China.
| |
Collapse
|
67
|
D’Arienzo V, Magri A, Harris JM, Wing PAC, Ko C, Rubio CO, Revill PA, Protzer U, Balfe P, McKeating JA. A PCR assay to quantify patterns of HBV transcription. J Gen Virol 2021; 102:001373. [PMID: 31846416 PMCID: PMC7610515 DOI: 10.1099/jgv.0.001373] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2019] [Accepted: 11/27/2019] [Indexed: 12/11/2022] Open
Abstract
Hepatitis B virus (HBV) is the prototype member of the family Hepadnaviridae and replicates via episomal copies of a covalently closed circular DNA (cccDNA) genome of approximately 3.2 kb. The chromatinization of this small viral genome, with overlapping open reading frames and regulatory elements, suggests an important role for epigenetic pathways to regulate HBV transcription. However, the host pathways that regulate HBV transcription and the temporal nature of promoter usage in infected cells are not well understood, in part due to the compact genome structure and overlapping open reading frames. To address this we developed a simple and cost-effective PCR assay to quantify the major viral RNAs and validated this technique using current state-of-art de novo HBV infection model systems. Our PCR method is three orders of magnitude more sensitive than Northern blot and requires relatively small amounts of starting material, making this an attractive tool for assessing HBV transcription.
Collapse
Affiliation(s)
- Valentina D’Arienzo
- Nuffield Department of Medicine, University of Oxford, Old Road Campus, Roosevelt Drive, Oxford, UK
| | - Andrea Magri
- Nuffield Department of Medicine, University of Oxford, Old Road Campus, Roosevelt Drive, Oxford, UK
| | - James M. Harris
- Nuffield Department of Medicine, University of Oxford, Old Road Campus, Roosevelt Drive, Oxford, UK
| | - Peter A. C. Wing
- Nuffield Department of Medicine, University of Oxford, Old Road Campus, Roosevelt Drive, Oxford, UK
| | - Chunkyu Ko
- Institute of Virology, Technische Universität, München/Helmholtz Zentrum München, Germany
| | - Claudia Orbegozo Rubio
- Nuffield Department of Medicine, University of Oxford, Old Road Campus, Roosevelt Drive, Oxford, UK
| | - Peter A. Revill
- Victorian Infectious Diseases Reference Laboratory, Royal Melbourne Hospital at the Peter Doherty Institute of Infection and Immunity, Melbourne, Australia
- Department of Microbiology and Immunology, University of Melbourne, Melbourne, Australia
| | - Ulrike Protzer
- Institute of Virology, Technische Universität, München/Helmholtz Zentrum München, Germany
- German Center for Infection Research (DZIF), Munich partner site, Munich, Germany
| | - Peter Balfe
- Nuffield Department of Medicine, University of Oxford, Old Road Campus, Roosevelt Drive, Oxford, UK
- Institute of Immunology and Immunotherapy, University of Birmingham, UK
| | - Jane A. McKeating
- Nuffield Department of Medicine, University of Oxford, Old Road Campus, Roosevelt Drive, Oxford, UK
| |
Collapse
|
68
|
HBV-Integration Studies in the Clinic: Role in the Natural History of Infection. Viruses 2021; 13:v13030368. [PMID: 33652619 PMCID: PMC7996909 DOI: 10.3390/v13030368] [Citation(s) in RCA: 46] [Impact Index Per Article: 15.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2021] [Revised: 02/21/2021] [Accepted: 02/22/2021] [Indexed: 02/06/2023] Open
Abstract
Hepatitis B virus (HBV) infection is a major global health problem causing acute and chronic liver disease that can lead to liver cirrhosis and hepatocellular carcinoma (HCC). HBV covalently closed circular DNA (cccDNA) is essential for viral replication and the establishment of a persistent infection. Integrated HBV DNA represents another stable form of viral DNA regularly observed in the livers of infected patients. HBV DNA integration into the host genome occurs early after HBV infection. It is a common occurrence during the HBV life cycle, and it has been detected in all the phases of chronic infection. HBV DNA integration has long been considered to be the main contributor to liver tumorigenesis. The recent development of highly sensitive detection methods and research models has led to the clarification of some molecular and pathogenic aspects of HBV integration. Though HBV integration does not lead to replication-competent transcripts, it can act as a stable source of viral RNA and proteins, which may contribute in determining HBV-specific T-cell exhaustion and favoring virus persistence. The relationship between HBV DNA integration and the immune response in the liver microenvironment might be closely related to the development and progression of HBV-related diseases. While many new antiviral agents aimed at cccDNA elimination or silencing have been developed, integrated HBV DNA remains a difficult therapeutic challenge.
Collapse
|
69
|
Hastings KL, Green MD, Gao B, Ganey PE, Roth RA, Burleson GR. Beyond Metabolism: Role of the Immune System in Hepatic Toxicity. Int J Toxicol 2021; 39:151-164. [PMID: 32174281 DOI: 10.1177/1091581819898399] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
The liver is primarily thought of as a metabolic organ; however, the liver is also an important mediator of immunological functions. Key perspectives on this emerging topic were presented in a symposium at the 2018 annual meeting of the American College of Toxicology entitled "Beyond metabolism: Role of the immune system in hepatic toxicity." Viral hepatitis is an important disease of the liver for which insufficient preventive vaccines exist. Host immune responses inadequately clear these viruses and often potentiate immunological inflammation that damages the liver. In addition, the liver is a key innate immune organ against bacterial infection. Hepatocytes and immune cells cooperatively control systemic and local bacterial infections. Conversely, bacterial infection can activate multiple types of immune cells and pathways to cause hepatocyte damage and liver injury. Finally, the immune system and specifically cytokines and drugs can interact in idiosyncratic drug-induced liver injury. This rare disease can result in a disease spectrum that ranges from mild to acute liver failure. The immune system plays a role in this disease spectrum.
Collapse
Affiliation(s)
| | | | - Bin Gao
- Laboratory of Liver Diseases, NIH, Bethesda, MD, USA
| | - Patricia E Ganey
- Department of Pharmacology and Toxicology, Michigan State University, East Lansing, MI, USA
| | - Robert A Roth
- Department of Pharmacology and Toxicology, Michigan State University, East Lansing, MI, USA
| | - Gary R Burleson
- BRT-Burleson Research Technologies, Inc, Morrisville, NC, USA
| |
Collapse
|
70
|
Abstract
Hepatitis B virus (HBV) core protein (Cp) can be found in the nucleus and cytoplasm of infected hepatocytes; however, it preferentially segregates to a specific compartment correlating with disease status. Regulation of this intracellular partitioning of Cp remains obscure. In this paper, we report that cellular compartments are filled and vacated by Cp in a time- and concentration-dependent manner in both transfections and infections. At early times after transfection, Cp, in a dimeric state, preferentially localizes to the nucleolus. Later, the nucleolar compartment is emptied and Cp progresses to being predominantly nuclear, with a large fraction of the protein in an assembled state. Nuclear localization is followed by cell-wide distribution, and then Cp becomes exclusively cytoplasmic. The same trend in Cp movement is seen during an infection. Putative nucleolar retention signals have been identified and appear to be structure dependent. Export of Cp from the nucleus involves the CRM1 exportin. Time-dependent flux can be recapitulated by modifying Cp concentration, suggesting transitions are regulated by reaching a threshold concentration.
Collapse
|
71
|
Liaw YF. Hepatitis B Flare After Cessation of Nucleos(t)ide Analogue Therapy in HBeAg-Negative Chronic Hepatitis B: To Retreat or Not to Retreat. Hepatology 2021; 73:843-852. [PMID: 32810321 DOI: 10.1002/hep.31525] [Citation(s) in RCA: 23] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/13/2020] [Revised: 07/14/2020] [Accepted: 08/03/2020] [Indexed: 12/17/2022]
Affiliation(s)
- Yun-Fan Liaw
- Liver Research UnitChang Gung Memorial HospitalChang Gung University College of MedicineTaipeiTaiwan
| |
Collapse
|
72
|
D’Arienzo V, Ferguson J, Giraud G, Chapus F, Harris JM, Wing PAC, Claydon A, Begum S, Zhuang X, Balfe P, Testoni B, McKeating JA, Parish JL. The CCCTC-binding factor CTCF represses hepatitis B virus enhancer I and regulates viral transcription. Cell Microbiol 2021; 23:e13274. [PMID: 33006186 PMCID: PMC7116737 DOI: 10.1111/cmi.13274] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2020] [Revised: 09/09/2020] [Accepted: 09/29/2020] [Indexed: 12/17/2022]
Abstract
Hepatitis B virus (HBV) infection is of global importance with over 2 billion people exposed to the virus during their lifetime and at risk of progressive liver disease, cirrhosis and hepatocellular carcinoma. HBV is a member of the Hepadnaviridae family that replicates via episomal copies of a covalently closed circular DNA (cccDNA) genome. The chromatinization of this small viral genome, with overlapping open reading frames and regulatory elements, suggests an important role for epigenetic pathways to regulate viral transcription. The chromatin-organising transcriptional insulator protein, CCCTC-binding factor (CTCF), has been reported to regulate transcription in a diverse range of viruses. We identified two conserved CTCF binding sites in the HBV genome within enhancer I and chromatin immunoprecipitation (ChIP) analysis demonstrated an enrichment of CTCF binding to integrated or episomal copies of the viral genome. siRNA knock-down of CTCF results in a significant increase in pre-genomic RNA levels in de novo infected HepG2 cells and those supporting episomal HBV DNA replication. Furthermore, mutation of these sites in HBV DNA minicircles abrogated CTCF binding and increased pre-genomic RNA levels, providing evidence of a direct role for CTCF in repressing HBV transcription.
Collapse
Affiliation(s)
| | - Jack Ferguson
- institute of Cancer and Genomic sciences, College of Medical and Dental Sciences, University of Birmingham, Birmingham, UK
| | - Guillaume Giraud
- CRCL INSERM and Cancer Research Center of Lyon (CRCL), Lyon, France
| | - Fleur Chapus
- CRCL INSERM and Cancer Research Center of Lyon (CRCL), Lyon, France
| | - James M. Harris
- Nuffield Department of Medicine, University of Oxford, Oxford, UK
| | - Peter A. C. Wing
- Nuffield Department of Medicine, University of Oxford, Oxford, UK
| | - Adam Claydon
- institute of Cancer and Genomic sciences, College of Medical and Dental Sciences, University of Birmingham, Birmingham, UK
| | - Sophia Begum
- institute of Cancer and Genomic sciences, College of Medical and Dental Sciences, University of Birmingham, Birmingham, UK
| | - Xiaodong Zhuang
- Nuffield Department of Medicine, University of Oxford, Oxford, UK
| | - Peter Balfe
- Nuffield Department of Medicine, University of Oxford, Oxford, UK
| | - Barbara Testoni
- CRCL INSERM and Cancer Research Center of Lyon (CRCL), Lyon, France
| | | | - Joanna L. Parish
- institute of Cancer and Genomic sciences, College of Medical and Dental Sciences, University of Birmingham, Birmingham, UK
| |
Collapse
|
73
|
Lebossé F, Inchauspé A, Locatelli M, Miaglia C, Diederichs A, Fresquet J, Chapus F, Hamed K, Testoni B, Zoulim F. Quantification and epigenetic evaluation of the residual pool of hepatitis B covalently closed circular DNA in long-term nucleoside analogue-treated patients. Sci Rep 2020; 10:21097. [PMID: 33273565 PMCID: PMC7712874 DOI: 10.1038/s41598-020-78001-1] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2020] [Accepted: 11/17/2020] [Indexed: 12/11/2022] Open
Abstract
Hepatitis B virus (HBV) covalently closed circular (ccc)DNA is the key genomic form responsible for viral persistence and virological relapse after treatment withdrawal. The assessment of residual intrahepatic cccDNA levels and activity after long-term nucleos(t)ide analogues therapy still represents a technical challenge. Quantitative (q)PCR, rolling circle amplification (RCA) and droplet digital (dd)PCR assays were used to quantify residual intrahepatic cccDNA in liver biopsies from 56 chronically HBV infected patients after 3 to 5 years of telbivudine treatment. Activity of residual cccDNA was evaluated by quantifying 3.5 kB HBV RNA (preC/pgRNA) and by assessing cccDNA-associated histone tails post-transcriptional modifications (PTMs) by micro-chromatin immunoprecipitation. Long-term telbivudine treatment resulted in serum HBV DNA suppression, with most of the patients reaching undetectable levels. Despite 38 out of 56 patients had undetectable cccDNA when assessed by qPCR, RCA and ddPCR assays detected cccDNA in all-but-one negative samples. Low preC/pgRNA level in telbivudine-treated samples was associated with enrichment for cccDNA histone PTMs related to repressed transcription. No difference in cccDNA levels was found according to serum viral markers evolution. This panel of cccDNA evaluation techniques should provide an added value for the new proof-of-concept clinical trials aiming at a functional cure of chronic hepatitis B.
Collapse
Affiliation(s)
- Fanny Lebossé
- INSERM U1052-Cancer Research Center of Lyon (CRCL), Lyon, France
- University of Lyon, UMR_S1052, CRCL, Lyon, France
- Department of Hepatology, Croix Rousse Hospital, Hospices Civils de Lyon, Lyon, France
| | - Aurore Inchauspé
- INSERM U1052-Cancer Research Center of Lyon (CRCL), Lyon, France
- University of Lyon, UMR_S1052, CRCL, Lyon, France
| | - Maëlle Locatelli
- INSERM U1052-Cancer Research Center of Lyon (CRCL), Lyon, France
- University of Lyon, UMR_S1052, CRCL, Lyon, France
| | - Clothilde Miaglia
- INSERM U1052-Cancer Research Center of Lyon (CRCL), Lyon, France
- University of Lyon, UMR_S1052, CRCL, Lyon, France
- Department of Hepatology, Croix Rousse Hospital, Hospices Civils de Lyon, Lyon, France
| | - Audrey Diederichs
- INSERM U1052-Cancer Research Center of Lyon (CRCL), Lyon, France
- University of Lyon, UMR_S1052, CRCL, Lyon, France
| | - Judith Fresquet
- INSERM U1052-Cancer Research Center of Lyon (CRCL), Lyon, France
- University of Lyon, UMR_S1052, CRCL, Lyon, France
| | - Fleur Chapus
- INSERM U1052-Cancer Research Center of Lyon (CRCL), Lyon, France
- University of Lyon, UMR_S1052, CRCL, Lyon, France
| | - Kamal Hamed
- Novartis Pharmaceuticals Corporation, East Hanover, NJ, USA
| | - Barbara Testoni
- INSERM U1052-Cancer Research Center of Lyon (CRCL), Lyon, France.
- University of Lyon, UMR_S1052, CRCL, Lyon, France.
| | - Fabien Zoulim
- INSERM U1052-Cancer Research Center of Lyon (CRCL), Lyon, France.
- University of Lyon, UMR_S1052, CRCL, Lyon, France.
- Department of Hepatology, Croix Rousse Hospital, Hospices Civils de Lyon, Lyon, France.
| |
Collapse
|
74
|
Correlation of serum hepatitis B core-related antigen with hepatitis B virus total intrahepatic DNA and covalently closed circular-DNA viral load in HIV-hepatitis B coinfection. AIDS 2020; 34:1943-1949. [PMID: 32773480 DOI: 10.1097/qad.0000000000002659] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
OBJECTIVE To assess whether quantified hepatitis B core-related antigen (qHBcrAg) is a surrogate marker of intrahepatic replication in HIV and hepatitis B virus (HBV) coinfection. DESIGN Cross-sectional study of 31 HIV-HBV-infected patients (total liver biopsies, n = 38) from a well defined cohort. METHODS Spearman's rank correlation coefficients were calculated between qHBcrAg and intrahepatic markers of HBV replication [total intrahepatic-DNA, covalently closed circular (ccc) DNA, cccDNA : total intrahepatic-DNA ratio]. RESULTS At biopsy, 22 (71.0%) patients were hepatitis B 'e' antigen (HBeAg)-positive, 22 (71.0%) had detectable plasma HBV-DNA, and 17 (54.8%) were treated with tenofovir. Median levels (interquartile range) of intrahepatic markers were as follows: HBV cccDNA (n = 34), 0.26 copies/cell (0.4-2.89); total intrahepatic-DNA (n = 38), 2.38 copies/cell (0.58-207.9), and cccDNA : total intrahepatic-DNA ratio (n = 34), 0.05 (interquartile range = 0.01-0.12). There was a significantly strong correlation between qHBcrAg and cccDNA in all patients (Rho = 0.65, P < 0.001), while a moderate correlation was observed between qHBcrAg and total intrahepatic-DNA (Rho = 0.57, P < 0.001) or cccDNA : total intrahepatic-DNA ratio (Rho = -0.45, P = 0.01). Similar findings were observed for HBeAg-positive patients and those with detectable HBV-DNA, with the exception of qHBcrAg and cccDNA or cccDNA : total intrahepatic-DNA ratio. In contrast, no significant correlation between qHBcrAg and any intrahepatic marker was observed in HBeAg-negative patients or those with undetectable HBV-DNA. No significant difference was observed in median qHBcrAg levels across liver fibrosis stages (P = 0.5). CONCLUSION qHBcrAg is a potential surrogate marker of cccDNA in HIV-HBV coinfected patients, yet might be less useful with undetectable serum HBV-DNA or HBeAg-negative status. Whether qHBcrAg provides further clinical utility compared with other serological markers remains debatable.
Collapse
|
75
|
Dandri M, Petersen J. cccDNA Maintenance in Chronic Hepatitis B - Targeting the Matrix of Viral Replication. Infect Drug Resist 2020; 13:3873-3886. [PMID: 33149632 PMCID: PMC7605611 DOI: 10.2147/idr.s240472] [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: 08/11/2020] [Accepted: 10/02/2020] [Indexed: 12/11/2022] Open
Abstract
Chronic hepatitis B is a numerically important cause of cirrhosis and hepatocellular carcinoma, despite an effective prophylactic vaccine and well-tolerated and effective oral antivirals. Both the incapacity of the immune system to clear hepatitis B virus (HBV) infection and the unique replication strategies adopted by HBV are considered key determinants of HBV chronicity. In this regard, the formation of the HBV DNA minichromosome, the covalently closed circular DNA (cccDNA), in the nucleus of infected hepatocytes, is essential not only for the production of all viral proteins but also for HBV persistence even after long-term antiviral therapy. Licensed polymerase inhibitors target the HBV reverse transcriptase activity, control the disease with long-term therapy but fail to eliminate the cccDNA. Consequently, the production of viral RNAs and proteins, including the hepatitis B surface antigen (HBsAg), is not abolished. Novel therapeutic efforts that are in the pipeline for early clinical trials explore novel targets and molecules. Such therapeutic efforts focus on achieving a functional cure, which is defined by the loss of HBsAg and undetectable HBV DNA levels in serum. Since a true cure of HBV infection requires the elimination of the cccDNA from infected cells, comprehension of the mechanisms implicated in cccDNA biogenesis, regulation and stability appears necessary to achieve HBV eradication. In this review, we will summarize the state of knowledge on cccDNA metabolism, focusing on insights suggesting potential weak points of the cccDNA that may be key for the development of therapeutic approaches and design of clinical trials aiming at lowering cccDNA loads and activity.
Collapse
Affiliation(s)
- Maura Dandri
- Department of Internal Medicine, University Medical Center Hamburg - Eppendorf, Hamburg, Germany.,German Center for Infection Research (DZIF), Hamburg-Luebeck-Borstel-Riems Site, Germany
| | - Joerg Petersen
- Institute for Interdisciplinary Medicine, Asklepios Klinik St Georg, University of Hamburg, Hamburg, Germany
| |
Collapse
|
76
|
Preclinical Profile and Characterization of the Hepatitis B Virus Core Protein Inhibitor ABI-H0731. Antimicrob Agents Chemother 2020; 64:AAC.01463-20. [PMID: 32868329 PMCID: PMC7577125 DOI: 10.1128/aac.01463-20] [Citation(s) in RCA: 38] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2020] [Accepted: 08/13/2020] [Indexed: 12/13/2022] Open
Abstract
ABI-H0731, a first-generation hepatitis B virus (HBV) core protein inhibitor, has demonstrated effective antiviral activity in chronic hepatitis B (CHB) patients in a phase 1b clinical trial and is currently being further evaluated in phase 2 clinical trials. Here, we report the preclinical profile of ABI-H0731. In in vitro cell culture systems (HepG2-derived cell lines HepAD38 and HepG2-NTCP and primary human hepatocytes [PHHs]), ABI-H0731 exhibited selective inhibition of HBV DNA replication (50% effective concentration [EC50] from 173 nM to 307 nM). ABI-H0731, a first-generation hepatitis B virus (HBV) core protein inhibitor, has demonstrated effective antiviral activity in chronic hepatitis B (CHB) patients in a phase 1b clinical trial and is currently being further evaluated in phase 2 clinical trials. Here, we report the preclinical profile of ABI-H0731. In in vitro cell culture systems (HepG2-derived cell lines HepAD38 and HepG2-NTCP and primary human hepatocytes [PHHs]), ABI-H0731 exhibited selective inhibition of HBV DNA replication (50% effective concentration [EC50] from 173 nM to 307 nM). Most importantly, ABI-H0731 suppressed covalently closed circular DNA (cccDNA) formation in two de novo infection models with EC50s from 1.84 μM to 7.3 μM. Mechanism-of-action studies indicated that ABI-H0731 is a direct-acting antiviral that targets HBV core protein, preventing HBV pregenomic RNA (pgRNA) encapsidation and subsequent DNA replication. The combination of ABI-H0731 with entecavir appears to decrease viral DNA faster and deeper than nucleoside/nucleotide analogue (NrtI) therapy alone. In addition, ABI-H0731 disrupts incoming nucleocapsids, causing the premature release of relaxed circular DNA (rcDNA) before delivery to the nucleus, and thus prevents new cccDNA formation. ABI-H0731 exhibits pangenotypic activity and is additive to moderately synergistic when combined with an NrtI. In addition to its potency and novel mechanism of action, ABI-H0731 possesses drug-like properties and a preclinical pharmacokinetic profile supportive of once-daily dosing in patients with CHB. Taken together, these data support the ongoing clinical development of ABI-H0731 as a treatment for HBV.
Collapse
|
77
|
Occult hepatitis B infection and hepatocellular carcinoma: Epidemiology, virology, hepatocarcinogenesis and clinical significance. J Hepatol 2020; 73:952-964. [PMID: 32504662 DOI: 10.1016/j.jhep.2020.05.042] [Citation(s) in RCA: 106] [Impact Index Per Article: 26.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/18/2020] [Revised: 05/21/2020] [Accepted: 05/25/2020] [Indexed: 12/12/2022]
Abstract
Occult hepatitis B infection (OBI) refers to a condition where replication-competent HBV DNA is present in the liver, with or without HBV DNA in the blood, in individuals with serum HBsAg negativity assessed by currently available assays. The episomal covalently closed circular DNA (cccDNA) in OBI is in a low replicative state. Viral gene expression is mediated by epigenetic control of HBV transcription, including the HBV CpG island methylation pathway and post-translational modification of cccDNA-bound histone, with a different pattern from patients with chronic HBV infection. The prevalence of OBI varies tremendously across patient populations owing to numerous factors, such as geographic location, assay characteristics, host immune response, coinfection with other viruses, and vaccination status. Apart from the risk of viral reactivation upon immunosuppression and the risk of transmission of HBV, OBI has been implicated in hepatocellular carcinoma (HCC) development in patients with chronic HCV infection, those with cryptogenic or known liver disease, and in patients with HBsAg seroclearance after chronic HBV infection. An increasing number of prospective studies and meta-analyses have reported a higher incidence of HCC in patients with HCV and OBI, as well as more advanced tumour histological grades and earlier age of HCC diagnosis, compared with patients without OBI. The proposed pathogenetic mechanisms of OBI-related HCC include the influence of HBV DNA integration on the hepatocyte cell cycle, the production of pro-oncogenic proteins (HBx protein and mutated surface proteins), and persistent low-grade necroinflammation (contributing to the development of fibrosis and cirrhosis). There remain uncertainties about exactly how, and in what order, these mechanisms drive the development of tumours in patients with OBI.
Collapse
|
78
|
Alexopoulou A, Vasilieva L, Karayiannis P. New Approaches to the Treatment of Chronic Hepatitis B. J Clin Med 2020; 9:jcm9103187. [PMID: 33019573 PMCID: PMC7601587 DOI: 10.3390/jcm9103187] [Citation(s) in RCA: 40] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2020] [Revised: 09/26/2020] [Accepted: 09/28/2020] [Indexed: 02/07/2023] Open
Abstract
The currently recommended treatment for chronic hepatitis B virus (HBV) infection achieves only viral suppression whilst on therapy, but rarely hepatitis B surface antigen (HBsAg) loss. The ultimate therapeutic endpoint is the combination of HBsAg loss, inhibition of new hepatocyte infection, elimination of the covalently closed circular DNA (cccDNA) pool, and restoration of immune function in order to achieve virus control. This review concentrates on new antiviral drugs that target different stages of the HBV life cycle (direct acting antivirals) and others that enhance both innate and adaptive immunity against HBV (immunotherapy). Drugs that block HBV hepatocyte entry, compounds that silence or deplete the cccDNA pool, others that affect core assembly, agents that degrade RNase-H, interfering RNA molecules, and nucleic acid polymers are likely interventions in the viral life cycle. In the immunotherapy category, molecules that activate the innate immune response such as Toll-like-receptors, Retinoic acid Inducible Gene-1 (RIG-1) and stimulator of interferon genes (STING) agonists or checkpoint inhibitors, and modulation of the adaptive immunity by therapeutic vaccines, vector-based vaccines, or adoptive transfer of genetically-engineered T cells aim towards the restoration of T cell function. Future therapeutic trends would likely be a combination of one or more of the aforementioned drugs that target the viral life cycle and at least one immunomodulator.
Collapse
Affiliation(s)
- Alexandra Alexopoulou
- Department of Medicine, Medical School, National & Kapodistrian University of Athens, Hippokration General Hospital, 11527 Athens, Greece;
- Correspondence: ; Tel.: +30-2132-088-178; Fax: +30-2107-706-871
| | - Larisa Vasilieva
- Department of Medicine, Medical School, National & Kapodistrian University of Athens, Hippokration General Hospital, 11527 Athens, Greece;
| | - Peter Karayiannis
- Department of Basic and Clinical Sciences, Medical School, University of Nicosia, Engomi, CY-1700 Nicosia, Cyprus;
| |
Collapse
|
79
|
Yuan Y, Yuan H, Yang G, Yun H, Zhao M, Liu Z, Zhao L, Geng Y, Liu L, Wang J, Zhang H, Wang Y, Zhang XD. IFN-α confers epigenetic regulation of HBV cccDNA minichromosome by modulating GCN5-mediated succinylation of histone H3K79 to clear HBV cccDNA. Clin Epigenetics 2020; 12:135. [PMID: 32894195 PMCID: PMC7487718 DOI: 10.1186/s13148-020-00928-z] [Citation(s) in RCA: 36] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2019] [Accepted: 08/26/2020] [Indexed: 02/06/2023] Open
Abstract
Background Hepatitis B virus covalently closed circular DNA (HBV cccDNA) is assembled by histones and non-histones into a chromatin-like cccDNA minichromosome in the nucleus. The cellular histone acetyltransferase GCN5, displaying succinyltransferase activity, is recruited onto cccDNA to modulate HBV transcription in cells. Clinically, IFN-α is able to repress cccDNA. However, the underlying mechanism of IFN-α in the depression of cccDNA mediated by GCN5 is poorly understood. Here, we explored the effect of IFN-α on GCN5-mediated succinylation in the epigenetic regulation of HBV cccDNA minichromosome. Results Succinylation modification of the cccDNA minichromosome has been observed in HBV-infected human liver-chimeric mice and HBV-expressing cell lines. Moreover, histone H3K79 succinylation by GCN5 was identified in the system. Interestingly, the mutant of histone H3K79 efficiently blocked the replication of HBV, and interference with GCN5 resulted in decreased levels of HBV DNA, HBsAg, and HBeAg in the supernatant from de novo HBV-infected HepaRG cells. Consistently, the levels of histone H3K79 succinylation were significantly elevated in the livers of HBV-infected human liver-chimeric mice. The knockdown or overexpression of GCN5 or the mutant of GCN5 could affect the binding of GCN5 to cccDNA or H3K79 succinylation, leading to a change in cccDNA transcription activity. In addition, Southern blot analysis validated that siGCN5 decreased the levels of cccDNA in the cells, suggesting that GCN5-mediated succinylation of histone H3K79 contributes to the epigenetic regulation of cccDNA minichromosome. Strikingly, IFN-α effectively depressed histone H3K79 succinylation in HBV cccDNA minichromosome in de novo HepG2-NTCP and HBV-infected HepaRG cells. Conclusions IFN-α epigenetically regulates the HBV cccDNA minichromosome by modulating GCN5-mediated succinylation of histone H3K79 to clear HBV cccDNA. Our findings provide new insights into the mechanism by which IFN-α modulate the epigenetic regulation of HBV cccDNA minichromosome.
Collapse
Affiliation(s)
- Ying Yuan
- Nankai University, 94 Weijin Road, Tianjin, 300071, People's Republic of China
| | - Hongfeng Yuan
- Nankai University, 94 Weijin Road, Tianjin, 300071, People's Republic of China
| | - Guang Yang
- Nankai University, 94 Weijin Road, Tianjin, 300071, People's Republic of China
| | - Haolin Yun
- Nankai University, 94 Weijin Road, Tianjin, 300071, People's Republic of China
| | - Man Zhao
- Nankai University, 94 Weijin Road, Tianjin, 300071, People's Republic of China
| | - Zixian Liu
- Nankai University, 94 Weijin Road, Tianjin, 300071, People's Republic of China
| | - Lina Zhao
- Nankai University, 94 Weijin Road, Tianjin, 300071, People's Republic of China
| | - Yu Geng
- Nankai University, 94 Weijin Road, Tianjin, 300071, People's Republic of China
| | - Lei Liu
- Nankai University, 94 Weijin Road, Tianjin, 300071, People's Republic of China
| | - Jiapei Wang
- Nankai University, 94 Weijin Road, Tianjin, 300071, People's Republic of China
| | - Huihui Zhang
- Nankai University, 94 Weijin Road, Tianjin, 300071, People's Republic of China
| | - Yufei Wang
- Nankai University, 94 Weijin Road, Tianjin, 300071, People's Republic of China
| | - Xiao-Dong Zhang
- Nankai University, 94 Weijin Road, Tianjin, 300071, People's Republic of China.
| |
Collapse
|
80
|
Zhao Z, Meng J, Su R, Zhang J, Chen J, Ma X, Xia Q. Epitranscriptomics in liver disease: Basic concepts and therapeutic potential. J Hepatol 2020; 73:664-679. [PMID: 32330603 DOI: 10.1016/j.jhep.2020.04.009] [Citation(s) in RCA: 85] [Impact Index Per Article: 21.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/28/2020] [Revised: 04/05/2020] [Accepted: 04/07/2020] [Indexed: 02/07/2023]
Abstract
The development of next-generation sequencing technology and the discovery of specific antibodies targeting chemically modified nucleotides have paved the way for a new era of epitranscriptomics. Cellular RNA is known to dynamically and reversibly undergo different chemical modifications after transcription, such as N6-methyladenosine (m6A), N1-methyladenosine, N6,2'-O-dimethyladenosine, 5-methylcytosine, and 5-hydroxymethylcytidine, whose identity and location comprise the field of epitranscriptomics. Dynamic post-transcriptional modifications determine the fate of target RNAs by regulating various aspects of their processing, including RNA export, transcript processing, splicing, and degradation. The most abundant internal mRNA modification in eukaryotic cells is m6A, which exhibits essential roles in physiological processes, such as embryogenesis, carcinogenesis, and neurogenesis. m6A is deposited by the m6A methyltransferase complex (composed of METTL3/14/16, WTAP, KIAA1429, and RBM15/15B), erased by demethylases (FTO and ALKBH5), and recognised by binding proteins (e.g., YTHDF1/2/3, YTHDC1/2, IGF2BP1/2/3). The liver is the largest digestive and metabolic organ, and m6A modifications play unique roles in critical physiological hepatic functions and various liver diseases. This review focuses on the biological roles of m6A RNA methylation in lipid metabolism, viral hepatitis, non-alcoholic fatty liver disease, liver cancer, and tumour metastasis. In addition, we summarise the existing inhibitors targeting m6A regulators and discuss the potential of modulating m6A modifications as a therapeutic strategy.
Collapse
Affiliation(s)
- Zhicong Zhao
- Department of Liver Surgery, Renji Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai 200127, China; Department of Systems Biology, Beckman Research Institute of City of Hope, Monrovia, CA 91016, USA
| | - Jiaxiang Meng
- Department of Liver Surgery, Renji Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai 200127, China
| | - Rui Su
- Department of Systems Biology, Beckman Research Institute of City of Hope, Monrovia, CA 91016, USA
| | - Jun Zhang
- Division of Gastroenterology and Hepatology, Key Laboratory of Gastroenterology and Hepatology, Ministry of Health, State Key Laboratory for Oncogenes and Related Genes, Renji Hospital, School of Medicine, Shanghai Jiao Tong University; Shanghai Institute of Digestive Disease, Shanghai 200001, China
| | - Jianjun Chen
- Department of Systems Biology, Beckman Research Institute of City of Hope, Monrovia, CA 91016, USA
| | - Xiong Ma
- Division of Gastroenterology and Hepatology, Key Laboratory of Gastroenterology and Hepatology, Ministry of Health, State Key Laboratory for Oncogenes and Related Genes, Renji Hospital, School of Medicine, Shanghai Jiao Tong University; Shanghai Institute of Digestive Disease, Shanghai 200001, China.
| | - Qiang Xia
- Department of Liver Surgery, Renji Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai 200127, China.
| |
Collapse
|
81
|
Ma Y, Wang J, Xiong F, Lu J. Extended duration therapy regimens based on Pegylated interferon for chronic hepatitis B patients focusing on hepatitis B surface antigen loss: A systematic review and meta-analysis. INFECTION GENETICS AND EVOLUTION 2020; 85:104492. [PMID: 32763441 DOI: 10.1016/j.meegid.2020.104492] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/24/2020] [Revised: 07/31/2020] [Accepted: 08/01/2020] [Indexed: 02/08/2023]
Abstract
AIMS Hepatitis B surface antigen (HBsAg) loss is associated with disease control and improvement of prognosis. Therefore, it is regarded as the optimal treatment endpoint for chronic hepatitis B (CHB) patients. Pegylated interferon (PegIFN)-based extended therapy regimens was assessed in several studies. In order to summarize a conclusion on the HBsAg loss rate and safety in this regimen, a systematic review and meta-analysis was performed. METHODS Studies on Hepatitis B and PegIFN were searched thoroughly in Pubmed, EMBASE, and the Cochrane Library from inception to November 18, 2019. The primary endpoint of this study was the HBsAg loss rate at the end of the extended duration therapy. The secondary endpoint was safety. All analyses were performed by using the R3.6.1 version Software. Quality assessment of RCTs was carried out by using Review manager 5.3. RESULTS A total of nine studies, including 545 CHB patients met the inclusion criteria. The pooled HBsAg loss rate after PegIFN-based extended duration therapy was 11% (95% CI: 0.05-0.19), I2 = 82%, P < 0.01(Q test). The extended duration therapy regimen was safe and tolerable. Subgroup analysis showed HBsAg loss rates were 14% (95% CI: 0.04-0.29) and 10% (95% CI: 0.02-0.20) respectively for HBeAg positive and HBeAg negative patients (P = 0.52). HBsAg loss rates were 11%(95%CI:0.03-0.22)and 12%(95%CI:0.04-0.24)respectively for PegIFN monotherapy and PegIFN with Nucleos(t)ide analogs (NAs) therapy (P = 0.84). HBsAg loss rates were 25% (95% CI: 0.19-0.31) and 8% (95% CI: 0.03-0.15) respectively for the advantageous group and non-advantageous group (P = 0.001). CONCLUSIONS For CHB patients, extended duration of PegIFNα-based treatment for more than 48 weeks is likely to improve HBsAg clearance rate. Specially, the advantageous group will benefit a lot. In addition, the extended duration therapy regimen is safe and tolerable.
Collapse
Affiliation(s)
- Yanpin Ma
- International Medical Department, Beijing You-an Hospital, Capital Medical University, Beijing, China
| | - Jinhuan Wang
- International Medical Department, Beijing You-an Hospital, Capital Medical University, Beijing, China
| | - Fang Xiong
- International Medical Department, Beijing You-an Hospital, Capital Medical University, Beijing, China
| | - Jun Lu
- International Medical Department, Beijing You-an Hospital, Capital Medical University, Beijing, China.
| |
Collapse
|
82
|
An Alternatively Spliced Sirtuin 2 Isoform 5 Inhibits Hepatitis B Virus Replication from cccDNA by Repressing Epigenetic Modifications Made by Histone Lysine Methyltransferases. J Virol 2020; 94:JVI.00926-20. [PMID: 32493816 DOI: 10.1128/jvi.00926-20] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2020] [Accepted: 05/12/2020] [Indexed: 02/07/2023] Open
Abstract
Sirtuin 2 (Sirt2), an NAD+-dependent protein deacetylase, deacetylates tubulin, AKT, and other proteins. Previously, we showed that Sirt2 isoform 1 (Sirt2.1) increased replication of hepatitis B virus (HBV). Here, we show that HBV replication upregulates the expression of Sirt2 primary and alternatively spliced transcripts and their respective isoforms, 1, 2, and 5. Since Sirt2 isoform 5 (Sirt2.5) is a catalytically inactive nuclear protein with a spliced-out nuclear export signal (NES), we speculated that its different localization affects its activity. The overexpression of Sirt2.5 reduced expression of HBV mRNAs, replicative intermediate DNAs, and covalently closed circular DNA (cccDNA), an activity opposite that of Sirt2.1 and Sirt2.2. Unlike the Sirt2.1-AKT interaction, the Sirt2.5-AKT interaction was weakened by HBV replication. Unlike Sirt2.1, Sirt2.5 activated the AKT/GSK-3β/β-catenin signaling pathway very weakly and independently of HBV replication. When the NES and an N-terminal truncated catalytic domain were added to the Sirt2.5 construct, it localized in the cytoplasm and increased HBV replication (like Sirt2.1 and Sirt2.2). Chromatin immunoprecipitation assays revealed that more Sirt2.5 was recruited to cccDNA than Sirt2.1. The recruitment of histone lysine methyltransferases (HKMTs), such as SETDB1, SUV39H1, EZH2, and PR-Set7, and their respective transcriptional repressive markers, H3K9me3, H3K27me3, and H4K20me1, to cccDNA also increased in Sirt2.5-overexpressing cells. Among these, the Sirt2.5-PR-Set7 and -SETDB1 interactions increased upon HBV replication. These results demonstrate that Sirt2.5 reduces cccDNA levels and viral transcription through epigenetic modification of cccDNA via direct and/or indirect association with HKMTs, thereby exhibiting anti-HBV activity.IMPORTANCE Sirt2, a predominant cytoplasmic α-tubulin deacetylase, promotes the growth of hepatocellular carcinoma; indeed, HBV replication increases Sirt2 expression, and overexpression of Sirt2 is associated with hepatic fibrosis and epithelial-to-mesenchymal transition. Increased amounts of Sirt2 isoforms 1, 2, and 5 upon HBV replication might further upregulate HBV replication, leading to a vicious cycle of virus replication/disease progression. However, we show here that catalytically inactive nuclear Sirt2.5 antagonizes the effects of Sirt2.1 and Sirt2.2 on HBV replication, thereby inhibiting cccDNA level, transcription of cccDNA, and subsequent synthesis of replicative intermediate DNA. More Sirt2.5 was recruited to cccDNA than Sirt2.1, thereby increasing epigenetic modification by depositing transcriptional repressive markers, possibly through direct and/or indirect association with histone lysine methyltransferases, such as SETDB1, SUV39H1, EZH2, and/or PR-Set7, which represses HBV transcription. Thus, Sirt2.5 might provide a functional cure for HBV by silencing the transcription of HBV.
Collapse
|
83
|
Wang Z, Wang W, Wang L. Epigenetic regulation of covalently closed circular DNA minichromosome in hepatitis B virus infection. BIOPHYSICS REPORTS 2020. [DOI: 10.1007/s41048-020-00112-z] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
|
84
|
Ji M, Mei X, Jing X, Xu X, Chen X, Pan W. The cooperative complex of Argonaute-2 and microRNA-146a regulates hepatitis B virus replication through flap endonuclease 1. Life Sci 2020; 257:118089. [PMID: 32659369 DOI: 10.1016/j.lfs.2020.118089] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2020] [Revised: 06/18/2020] [Accepted: 07/08/2020] [Indexed: 02/08/2023]
Abstract
AIM Hepatitis B virus (HBV) is a major cause of a variety of liver diseases. Existing antiviral drugs cannot eradicate HBV from our body, and the main reason is unclear on the molecular mechanism of HBV replication. Flap endonuclease 1 (FEN1) can repair relaxed circular DNA (HBV rcDNA) to covalently closed circular DNA (HBV cccDNA) that promotes HBV DNA replication, while its specific regulatory detail remains unclear. In addition, miR-146a is close related to regulation in HBV replication. This study aims to explore whether miR-146a regulates HBV cccDNA formation through FEN1. MAIN METHODS We investigated the expression of miR-146a, FEN1 and HBV copies in HBV stable replication cell line HepG2.2.15 and its parent cell line HepG2 transfected miR-146a and FEN1 plasmid by qRT-PCR and western blot, to identify the cooperation of Argonaute-2 (Ago2) and miR-146a by Ago2 siRNA and Ago2 RNA Binding Protein Immunoprecipitation (RIP). KEY FINDINGS Compared with the control group, we found that the expression of miR-146a was significantly up-regulated in HepG2.2.15, and the expression of FEN1 and HBV copies were also significantly up-regulated. On contrary, the expression of target gene of miR-146a, interleukin-1 receptor-associated kinase 1 (IRAK1) and tumor necrosis factor receptor-associated factor-6 (TRAF6), was significantly decreased in HepG2.2.15. With the use of Ago2 siRNA and then Ago2 RIP, we found that Ago2 performed as a carrier for miR-146a to promote HBV replication. SIGNIFICANCE The results suggest a novel miR-146a → FEN1 → HBV DNA regulatory axis in HBV replication life. Ago2 cooperates with miR-146a to regulate the transcription and expression level of FEN1 protein through the downstream target gene IRAK1/TRAF6, and to promote HBV replication.
Collapse
Affiliation(s)
- Min Ji
- Experimental Teaching Center for Pathogen Biology and Immunology & Department of Microbiology and Immunology, North Sichuan Medical College, Nanchong 637000, China; Department of Infectious Diseases, Affiliated Hospital of North Sichuan Medical College, Nanchong 637100, China; People's Hospital of Jianyang, Chengdu, Sichuan 641400, China
| | - Xiaoping Mei
- Department of Infectious Diseases, Affiliated Hospital of North Sichuan Medical College, Nanchong 637100, China
| | - Xueming Jing
- Department of Infectious Diseases, Affiliated Hospital of North Sichuan Medical College, Nanchong 637100, China
| | - Xu Xu
- Experimental Teaching Center for Pathogen Biology and Immunology & Department of Microbiology and Immunology, North Sichuan Medical College, Nanchong 637000, China
| | - Xing Chen
- Department of Infectious Diseases, Affiliated Hospital of North Sichuan Medical College, Nanchong 637100, China
| | - Wanlong Pan
- Experimental Teaching Center for Pathogen Biology and Immunology & Department of Microbiology and Immunology, North Sichuan Medical College, Nanchong 637000, China.
| |
Collapse
|
85
|
Ligat G, Goto K, Verrier E, Baumert TF. Targeting Viral cccDNA for Cure of Chronic Hepatitis B. ACTA ACUST UNITED AC 2020; 19:235-244. [PMID: 36034467 PMCID: PMC7613435 DOI: 10.1007/s11901-020-00534-w] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Purpose of Review Chronic hepatitis B (CHB), caused by hepatitis B virus (HBV), is a major cause of advanced liver disease and hepatocellular carcinoma (HCC) worldwide. HBV replication is characterized by the synthesis of covalently closed circular (ccc) DNA which is not targeted by antiviral nucleos(t)ide analogues (NUCs) the key modality of standard of care. While HBV replication is successfully suppressed in treated patients, they remain at risk for developing HCC. While functional cure, characterized by loss of HBsAg, is the first goal of novel antiviral therapies, curative treatments eliminating cccDNA remain the ultimate goal. This review summarizes recent advances in the discovery and development of novel therapeutic strategies and their impact on cccDNA biology. Recent Findings Within the last decade, substantial progress has been made in the understanding of cccDNA biology including the discovery of host dependency factors, epigenetic regulation of cccDNA transcription and immune-mediated degradation. Several approaches targeting cccDNA either in a direct or indirect manner are currently at the stage of discovery, preclinical or early clinical development. Examples include genome-editing approaches, strategies targeting host dependency factors or epigenetic gene regulation, nucleocapsid modulators and immune-mediated degradation. Summary While direct-targeting cccDNA strategies are still largely at the preclinical stage of development, capsid assembly modulators and immune-based approaches have reached the clinical phase. Clinical trials are ongoing to assess their efficacy and safety in patients including their impact on viral cccDNA. Combination therapies provide additional opportunities to overcome current limitations of individual approaches.
Collapse
|
86
|
Ochi M, Otsuka M, Maruyama R, Koike K. HBx increases EGFR expression by inhibiting miR129-5p function. Biochem Biophys Res Commun 2020; 529:198-203. [PMID: 32703411 DOI: 10.1016/j.bbrc.2020.06.018] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2020] [Accepted: 06/04/2020] [Indexed: 12/29/2022]
Abstract
Despite the efficient suppression of hepatitis B virus (HBV) replication by nucelos(t)ide analogs, HBV RNA expression usually continues even during nucleots(t)ide analog therapy because episomal covalently closed circular DNA (ccDNA), which is the template for HBV RNA transcription, cannot be eliminated. Here, we found that the common sequences of all HBV RNAs and that encoding the X protein (HBx) have similarities with the sequences of a host cellular microRNA (miRNA), miR129-5p. HBx inhibits miR129-5p function, resulting in increased expression of ZBTB20, a target gene of miR129-5p. ZBTB20 activates transcription and increases cell-surface epidermal growth factor receptor (EGFR) levels, promoting the cell growth rate, and this effect was reversed through ZBTB20 knockdown. mir129-5p levels in Ago2-containing complexes were reduced by expression of HBx, suggesting that the viral RNA sequestered miR129-5p from Ago2-containing complexes. These results indicate the possibility that HBV RNA may maintain pathogenicity even through nucleos(t)ide analog therapy.
Collapse
Affiliation(s)
- Masanori Ochi
- Department of Gastroenterology, Graduate School of Medicine, The University of Tokyo, Tokyo, 113-8655, Japan.
| | - Motoyuki Otsuka
- Department of Gastroenterology, Graduate School of Medicine, The University of Tokyo, Tokyo, 113-8655, Japan.
| | - Reo Maruyama
- Project for Cancer Epigenomics, The Cancer Institute of the Japanese Foundation for Cancer Research, Tokyo, 135-8550, Japan.
| | - Kazuhiko Koike
- Department of Gastroenterology, Graduate School of Medicine, The University of Tokyo, Tokyo, 113-8655, Japan.
| |
Collapse
|
87
|
Jia L, Gao Y, He Y, Hooper JD, Yang P. HBV induced hepatocellular carcinoma and related potential immunotherapy. Pharmacol Res 2020; 159:104992. [PMID: 32505833 DOI: 10.1016/j.phrs.2020.104992] [Citation(s) in RCA: 57] [Impact Index Per Article: 14.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/24/2020] [Revised: 05/16/2020] [Accepted: 05/31/2020] [Indexed: 02/06/2023]
Abstract
Chronic infection of Hepatitis B virus (HBV) has long been recognized as a major risk factor in the initiation and development of hepatocellular carcinoma (HCC), contributing to over half the cases of HCC worldwide. Transformation of the liver with HBV infection to HCC mainly results from long-term interaction between HBV and the host hepatocytes via a variety of mechanisms, including HBV DNA integration, prolonged expression of the viral HBx regulatory protein and/or aberrant preS/S envelope proteins, and epigenetic dysregulation of tumor suppressor genes. While there have been several failures in the development of drugs for HCC, the immune-tolerant microenvironment of this malignancy suggests that immunotherapeutic agents could provide benefits for these patients. This is supported by recent data showing that immunotherapy has promising activity in patients with advanced HCC. In this review, we provide an overview of HBV-induced HCC and recent immune based approaches for the treatment of HCC patients.
Collapse
Affiliation(s)
- Liyang Jia
- Key Laboratory of Infection and Immunity of CAS, CAS Center for Excellence in Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, 100101 Beijing, China; University of Chinese Academy of Sciences, 100049 Beijing, China
| | - Yanan Gao
- Key Laboratory of Infection and Immunity of CAS, CAS Center for Excellence in Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, 100101 Beijing, China; University of Chinese Academy of Sciences, 100049 Beijing, China
| | - Yaowu He
- Mater Research Institute - University of Queensland, Translational Research Institute, Woolloongabba, QLD 4102, Australia
| | - John D Hooper
- Mater Research Institute - University of Queensland, Translational Research Institute, Woolloongabba, QLD 4102, Australia.
| | - Pengyuan Yang
- Key Laboratory of Infection and Immunity of CAS, CAS Center for Excellence in Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, 100101 Beijing, China; University of Chinese Academy of Sciences, 100049 Beijing, China.
| |
Collapse
|
88
|
Lee HW. [Long Term Efficacy of Antiviral Therapy: Mortality and Incidence of Hepatocellular Carcinoma]. THE KOREAN JOURNAL OF GASTROENTEROLOGY 2020; 74:251-257. [PMID: 31765553 DOI: 10.4166/kjg.2019.74.5.251] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/01/2019] [Revised: 11/14/2019] [Accepted: 11/15/2019] [Indexed: 01/27/2023]
Abstract
Multiple studies have shown that oral antiviral therapies reduced the incidence of hepatocellular carcinoma (HCC) and improved the survival of patients with chronic hepatitis B when compared with that of untreated patients. In particular, entecavir and tenofovir share the qualities of high efficacy in reducing the HBV DNA levels, and they have excellent tolerability and safety. These drugs modified the natural history of liver fibrosis, improve liver function, decrease the incidence of HCC, decrease the need for liver transplantation, and improve survival. Many studies have suggested that long-term antiviral therapy reduces the risk of HCC and liver cirrhosis in patients with chronic hepatitis. The mechanism of these drugs in reducing the risk of HCC is not clear. This article reviews the mechanisms of carcinogenic HBV by conducting a review of the literature on the efficacy of therapy for reducing the risk of HCC. A few recent articles have suggested that tenofovir offers advantages over entecavir in terms of HCC prevention, but these articles have the inherent limitations of observational data. No other head-to-head randomized trials exist. Further randomized studies would help provide stronger evidence of the association between the type of antiviral agent and the HCC outcomes. Only achieving complete viral eradication from the liver will truly decrease the mortality and incidence of HCC.
Collapse
Affiliation(s)
- Hyun Woong Lee
- Department of Internal Medicine, Gangnam Severance Hospital, Yonsei University College of Medicine, Seoul, Korea
| |
Collapse
|
89
|
Liu Y, Wang H, Zhang J, Yang J, Bai L, Zheng B, Zheng T, Wang Y, Li J, Zhang W. SERINC5 Inhibits the Secretion of Complete and Genome-Free Hepatitis B Virions Through Interfering With the Glycosylation of the HBV Envelope. Front Microbiol 2020; 11:697. [PMID: 32431673 PMCID: PMC7216740 DOI: 10.3389/fmicb.2020.00697] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2019] [Accepted: 03/25/2020] [Indexed: 12/22/2022] Open
Abstract
Serine incorporator 3 (SERINC3) and SERINC5 were recently identified as host intrinsic factors against human immunodeficiency virus (HIV)-1 and counteracted by HIV-1 Nef. However, whether they inhibit hepatitis B virus (HBV), which is a severe health problem worldwide, is unknown. Here, we demonstrate that SERINC5 potently inhibited HBV virion secretion in the supernatant without affecting intracellular core particle-associated DNA and the total RNA, but SERINC3 and SERINC1 did not. Further investigation discovered that SERINC5 increased the non-glycosylation of LHB, MHB, and SHB proteins of HBV and slightly decreased HBs proteins levels, which led to the decreased HBV secretion. Importantly, SERINC5 co-localized with LHB proteins in the Golgi apparatus, which is important for glycan processing and transport. In addition, we determined the functional domain in SERINC5 required for HBV inhibition, which was completely different from that required for HIV-1 restriction, whereas phosphorylation and glycosylation sites in SERINC5 were dispensable for HBV restriction. Taken together, our results demonstrate that SERINC5 suppresses HBV virion secretion through interfering with the glycosylation of HBV proteins, suggesting that SERINC5 might possess broad-spectrum antiviral activity.
Collapse
Affiliation(s)
- Yue Liu
- Institute of Virology and AIDS Research, The First Hospital of Jilin University, Changchun, China.,Department of Echocardiography, The First Hospital of Jilin University, Changchun, China
| | - Hong Wang
- Institute of Virology and AIDS Research, The First Hospital of Jilin University, Changchun, China
| | - Jun Zhang
- Institute of Virology and AIDS Research, The First Hospital of Jilin University, Changchun, China
| | - Jing Yang
- Institute of Virology and AIDS Research, The First Hospital of Jilin University, Changchun, China
| | - Lu Bai
- Key Laboratory of Medical Molecular Virology, Ministry of Education and Health, School of Basic Medical Sciences, Shanghai Medical College of Fudan University, Shanghai, China
| | - Baisong Zheng
- Institute of Virology and AIDS Research, The First Hospital of Jilin University, Changchun, China
| | - Tianhang Zheng
- Institute of Virology and AIDS Research, The First Hospital of Jilin University, Changchun, China
| | - Yingchao Wang
- Department of Hepatobiliary Pancreatic Surgery, The First Hospital of Jilin University, Changchun, China
| | - Jianhua Li
- Key Laboratory of Medical Molecular Virology, Ministry of Education and Health, School of Basic Medical Sciences, Shanghai Medical College of Fudan University, Shanghai, China
| | - Wenyan Zhang
- Institute of Virology and AIDS Research, The First Hospital of Jilin University, Changchun, China
| |
Collapse
|
90
|
El-Adly AM, Meshaal AK, Mekky MA, Hetta HF, Wardany AA, El-Shanawany AA. Diagnostic strategy for occult hepatitis B virus infection and its clinical implications among patients at Upper Egypt. JOURNAL OF RADIATION RESEARCH AND APPLIED SCIENCES 2020. [DOI: 10.1080/16878507.2020.1740396] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Affiliation(s)
- A. M. El-Adly
- Department of Botany and Microbiology, Faculty of Science, Al-Azhar University, Assiut, Egypt
| | - A. K. Meshaal
- Department of Botany and Microbiology, Faculty of Science, Al-Azhar University, Assiut, Egypt
| | - M. A. Mekky
- Department of Tropical Medicine and Gastroenterology, Faculty of Medicine, Assiut University Hospital, Assiut, Egypt
| | - H. F. Hetta
- Department of Medical Microbiology and Immunology, Faculty of Medicine, Assiut University, Assiut, Egypt
- Department of Internal Medicine, University of Cincinnati Medical Center, Cincinnati, OH, USA
| | - A. A. Wardany
- Department of Botany and Microbiology, Faculty of Science, Al-Azhar University, Assiut, Egypt
| | - A. A. El-Shanawany
- Department of Botany and Microbiology, Faculty of Science, Al-Azhar University, Assiut, Egypt
| |
Collapse
|
91
|
Dandri M. Epigenetic modulation in chronic hepatitis B virus infection. Semin Immunopathol 2020; 42:173-185. [PMID: 32185454 PMCID: PMC7174266 DOI: 10.1007/s00281-020-00780-6] [Citation(s) in RCA: 52] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2019] [Accepted: 01/08/2020] [Indexed: 02/06/2023]
Abstract
The human hepatitis B virus (HBV) is a small-enveloped DNA virus causing acute and chronic hepatitis. Despite the existence of an effective prophylactic vaccine and the strong capacity of approved antiviral drugs to suppress viral replication, chronic HBV infection (CHB) continues to be a major health burden worldwide. Both the inability of the immune system to resolve CHB and the unique replication strategy employed by HBV, which forms a stable viral covalently closed circular DNA (cccDNA) minichromosome in the hepatocyte nucleus, enable infection persistence. Knowledge of the complex network of interactions that HBV engages with its host is still limited but accumulating evidence indicates that epigenetic modifications occurring both on the cccDNA and on the host genome in the course of infection are essential to modulate viral activity and likely contribute to pathogenesis and cancer development. Thus, a deeper understanding of epigenetic regulatory processes may open new venues to control and eventually cure CHB. This review summarizes major findings in HBV epigenetic research, focusing on the epigenetic mechanisms regulating cccDNA activity and the modifications determined in infected host cells and tumor liver tissues.
Collapse
Affiliation(s)
- Maura Dandri
- I. Department of Internal Medicine, Center for Internal Medicine, University Medical Center Hamburg-Eppendorf, Martinistr. 52, 20246, Hamburg, Germany.
- German Center for Infection Research (DZIF), Hamburg-Lübeck-Borstel-Riems Site, Hamburg, Germany.
| |
Collapse
|
92
|
Prakash K, Larsson SB, Rydell GE, Andersson ME, Ringlander J, Norkrans G, Norder H, Lindh M. Hepatitis B Virus RNA Profiles in Liver Biopsies by Digital Polymerase Chain Reaction. Hepatol Commun 2020; 4:973-982. [PMID: 32626830 PMCID: PMC7327224 DOI: 10.1002/hep4.1507] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/11/2020] [Accepted: 02/25/2020] [Indexed: 12/16/2022] Open
Abstract
Replication of hepatitis B virus (HBV) originates from covalently closed circular DNA (cccDNA) and involves reverse transcription of pregenomic RNA (pgRNA), which is also called core RNA and encodes the capsid protein. The RNA coding for hepatitis B surface antigen (HBsAg) in the envelope of viral or subviral particles is produced from cccDNA or from HBV DNA integrated into the host genome. Because only cccDNA can generate the core and the 3′ redundancy regions of HBV RNA, we aimed to clarify to what extent such HBV integrations are expressed by quantifying the different HBV RNA species in liver tissue. Digital droplet polymerase chain reaction (ddPCR) was employed to quantify six HBV RNA targets in 76 liver biopsies from patients with chronic infection, comprising 14 who were hepatitis B e antigen (HBeAg) positive and 62 who were HBeAg negative. In patients who were HBeAg negative, HBV RNA from the S RNA region was >1.6 log10 units higher than in the core and 3′ redundancy regions (P < 0.0001), indicating that >90% of S RNA was integration derived. HBeAg‐negative samples showed 10 times lower levels of pgRNA (5′ core) compared with core RNA (3′ part of core; P < 0.0001), suggesting that a large proportion of core RNA might have a downstream shift of the transcription starting point. In multiple regression analysis, HBV DNA levels in serum were most strongly dependent on pgRNA. Conclusion: In patients who were HBeAg negative, integration‐derived S RNA seemed to predominate and a large proportion of the core RNA lacked the 5′ part. Because this part comprises the down‐regulator of transcription 1 sequences, which are necessary for virus production (plus strand translocation), the finding might help to explain the low level of HBV DNA in serum that frequently is observed in patients with chronic HBV infection who are HBeAg negative.
Collapse
Affiliation(s)
- Kasthuri Prakash
- Department of Infectious Diseases Sahlgrenska Academy University of Gothenburg Gothenburg Sweden
| | - Simon B Larsson
- Department of Infectious Diseases Sahlgrenska Academy University of Gothenburg Gothenburg Sweden
| | - Gustaf E Rydell
- Department of Infectious Diseases Sahlgrenska Academy University of Gothenburg Gothenburg Sweden
| | - Maria E Andersson
- Department of Infectious Diseases Sahlgrenska Academy University of Gothenburg Gothenburg Sweden
| | - Johan Ringlander
- Department of Infectious Diseases Sahlgrenska Academy University of Gothenburg Gothenburg Sweden
| | - Gunnar Norkrans
- Department of Infectious Diseases Sahlgrenska Academy University of Gothenburg Gothenburg Sweden
| | - Heléne Norder
- Department of Infectious Diseases Sahlgrenska Academy University of Gothenburg Gothenburg Sweden
| | - Magnus Lindh
- Department of Infectious Diseases Sahlgrenska Academy University of Gothenburg Gothenburg Sweden
| |
Collapse
|
93
|
In Vitro Systems for Studying Different Genotypes/Sub-Genotypes of Hepatitis B Virus: Strengths and Limitations. Viruses 2020; 12:v12030353. [PMID: 32210021 PMCID: PMC7150782 DOI: 10.3390/v12030353] [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] [Subscribe] [Scholar Register] [Received: 02/14/2020] [Revised: 03/04/2020] [Accepted: 03/06/2020] [Indexed: 12/11/2022] Open
Abstract
Hepatitis B virus (HBV) infects the liver resulting in end stage liver disease, cirrhosis, and hepatocellular carcinoma. Despite an effective vaccine, HBV poses a serious health problem globally, accounting for 257 million chronic carriers. Unique features of HBV, including its narrow virus-host range and its hepatocyte tropism, have led to major challenges in the development of suitable in vivo and in vitro model systems to recapitulate the HBV replication cycle and to test various antiviral strategies. Moreover, HBV is classified into at least nine genotypes and 35 sub-genotypes with distinct geographical distributions and prevalence, which have different natural histories of infection, clinical manifestation, and response to current antiviral agents. Here, we review various in vitro systems used to study the molecular biology of the different (sub)genotypes of HBV and their response to antiviral agents, and we discuss their strengths and limitations. Despite the advances made, no system is ideal for pan-genotypic HBV research or drug development and therefore further improvement is required. It is necessary to establish a centralized repository of HBV-related generated materials, which are readily accessible to HBV researchers, with international collaboration toward advancement and development of in vitro model systems for testing new HBV antivirals to ensure their pan-genotypic and/or customized activity.
Collapse
|
94
|
Mitochondria ubiquitin ligase, MARCH5 resolves hepatitis B virus X protein aggregates in the liver pathogenesis. Cell Death Dis 2019; 10:938. [PMID: 31819032 PMCID: PMC6901512 DOI: 10.1038/s41419-019-2175-z] [Citation(s) in RCA: 31] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2019] [Revised: 11/26/2019] [Accepted: 11/26/2019] [Indexed: 12/12/2022]
Abstract
Infection of hepatitis B virus (HBV) increase the incidence of chronic liver disease and hepatocellular carcinoma (HCC). The hepatitis B viral x (HBx) protein encoded by the HBV genome contributes to the pathogenesis of HCC and thus, negative regulation of HBx is beneficial for the alleviation of the disease pathogenesis. MARCH5 is a mitochondrial E3 ubiquitin ligase and here, we show that high MARCH5 expression levels are correlated with improved survival in HCC patients. MARCH5 interacts with HBx protein mainly accumulated in mitochondria and targets it for degradation. The N-terminal RING domain of MARCH5 was required for the interaction with HBx, and MARCH5H43W lacking E3 ligase activity failed to reduce HBx protein levels. High expression of HBx results in the formation of protein aggregates in semi-denaturing detergent agarose gels and MARCH5 mediates the elimination of protein aggregates through the proteasome pathway. HBx-induced ROS production, mitophagy, and cyclooxygenase-2 gene expression were suppressed in the presence of high MARCH5 expression. These results suggest MARCH5 as a target for alleviating HBV-mediated liver disease.
Collapse
|
95
|
Xiao Y, Liu C, Tang W, Zhang H, Chen X. Evans Blue Inhibits HBV Replication Through a Dual Antiviral Mechanism by Targeting Virus Binding and Capsid Assembly. Front Microbiol 2019; 10:2638. [PMID: 31798562 PMCID: PMC6868041 DOI: 10.3389/fmicb.2019.02638] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2019] [Accepted: 10/30/2019] [Indexed: 12/29/2022] Open
Abstract
Chronic hepatitis B (CHB) is a global health problem caused by human hepatitis B virus (HBV). Current treatment with interferons and nucleos(t)ide analogs (NAs) can cause population tolerance and drug resistance. Therefore, new antiviral drugs, especially those targeting host factors, are urgently needed. Here, we identified Evans blue as a new HBV inhibitor by screening an FDA drug library using Huh7DhNTCP cells and confirmed the antiviral activity in primary human hepatocytes and human sodium taurocholate cotransporting polypeptide (hNTCP)-transfected porcine primary hepatocytes. Our efficacy study showed that Evans blue has an IC50 of 2 μM against HBV infection in Huh7DhNTCP cells, and no apparent toxicity at up to 1000 μM. The IC50 of Evans blue against HBV in primary human hepatocytes was approximately 5 μM. Mechanism studies revealed that Evans blue has a dual anti-HBV effect. It inhibits both the binding of viral preS1 to host cells through the host factor NTCP and the virus capsid assembly by targeting the host factor BK channel. The KD of the direct interaction between Evans blue and NTCP is 8.82E-8 M. Evans blue can suppress capsid assembly at micromolar concentrations by reducing the cytosolic calcium ion concentration. Since the antiviral effects on HBV binding and assembly are both achieved through targeting host factors, Evans blue inhibits the infection of nucleos(t)ide analog drug-resistant HBV strains in Huh7DhNTCP cells. Taken together, our results suggest that Evans blue may be a promising anti-HBV drug candidate in the classes of both entry and assembly inhibitors.
Collapse
Affiliation(s)
- Yu Xiao
- State Key Laboratory of Virology, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan, China.,University of Chinese Academy of Sciences, Beijing, China
| | - Chunlan Liu
- State Key Laboratory of Virology, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan, China
| | - Wei Tang
- State Key Laboratory of Virology, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan, China
| | - Haiwei Zhang
- State Key Laboratory of Virology, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan, China
| | - Xulin Chen
- State Key Laboratory of Virology, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan, China.,University of Chinese Academy of Sciences, Beijing, China.,Guangdong Key Laboratory of Virology, Institute of Medical Microbiology, Jinan University, Guangzhou, China
| |
Collapse
|
96
|
Wu F, Cheng W, Zhao F, Tang M, Diao Y, Xu R. Association of N6-methyladenosine with viruses and related diseases. Virol J 2019; 16:133. [PMID: 31711514 PMCID: PMC6849232 DOI: 10.1186/s12985-019-1236-3] [Citation(s) in RCA: 41] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2019] [Accepted: 10/03/2019] [Indexed: 02/07/2023] Open
Abstract
Background N6-methyladenosine (m6A) modification is the most prevalent internal modification of eukaryotic mRNA modulating gene expression. m6A modification is a dynamic reversible process regulated by three protein groups: methyltransferases (writers), demethylases (erasers), and m6A-binding proteins (readers). m6A modification is involved in all phases of RNA metabolism, including RNA folding, stability, splicing, nuclear exporting, translational modulation and degradation. Main body In recent years, numerous studies have reported that abnormal m6A modification causes aberrant expression of important viral genes. Herein, we review the role of m6A in viral lifecycle and its contribution to the pathogenesis of human diseases. Particularly, we focus on the viruses associated with human diseases such as HIV-1, IAV, HBV, HCV, EBV and many others. Conclusions A better understanding of m6A-virus relationship would provide new insights into the viral replication process and pathogenesis of human diseases caused by viruses. In addition, exploration of the role of m6A in disease-causing viruses will reveal novel approaches for the treatment of such diseases.
Collapse
Affiliation(s)
- Fang Wu
- Engineering Research Center of Molecular Medicine, Ministry of Education, Huaqiao University, Xiamen, China.,School of Medicine, Huaqiao University, Xiamen, China
| | - Wenzhao Cheng
- Engineering Research Center of Molecular Medicine, Ministry of Education, Huaqiao University, Xiamen, China. .,Stem Cell Laboratory, The Second Affiliated Hospital, Fujian Medical University, Quanzhou, China.
| | - Feiyuan Zhao
- Engineering Research Center of Molecular Medicine, Ministry of Education, Huaqiao University, Xiamen, China.,School of Medicine, Huaqiao University, Xiamen, China
| | - Mingqing Tang
- Engineering Research Center of Molecular Medicine, Ministry of Education, Huaqiao University, Xiamen, China.,School of Medicine, Huaqiao University, Xiamen, China.,Fujian Provincial Key Laboratory of Molecular Medicine & Fujian Provincial Key Laboratory of Precision Medicine and Molecular Detection in Universities, Xiamen, China
| | - Yong Diao
- School of Medicine, Huaqiao University, Xiamen, China
| | - Ruian Xu
- Engineering Research Center of Molecular Medicine, Ministry of Education, Huaqiao University, Xiamen, China. .,School of Medicine, Huaqiao University, Xiamen, China. .,Fujian Provincial Key Laboratory of Molecular Medicine & Fujian Provincial Key Laboratory of Precision Medicine and Molecular Detection in Universities, Xiamen, China.
| |
Collapse
|
97
|
Ostankova YV, Semenov AV, Totolian AA. [The quantitative determination method of covalently closed circular DNA HBV in puncture biopsy specimens of the liver.]. Klin Lab Diagn 2019; 64:565-570. [PMID: 31610110 DOI: 10.18821/0869-2084-2019-64-9-565-570] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2019] [Accepted: 06/25/2019] [Indexed: 12/16/2022]
Abstract
To analyze the method HBV covalent-closed circular DNA quantitative determination in liver puncture biopsies and evaluate its significance in identifying HBsAg-negative viral hepatitis B. In this work, samples of liver tissue biopsy material were used from 128 patients living in St. Petersburg, in various regions of the Russian Federation, as well as in the Republic of Uzbekistan. For quantitative analysis of HBV covalently closed circular DNA in a biopsy material a method was developed based on real-time PCR using TaqMan probes for the target fragment and for the endogenous reference gene, based on the detecting ccc HBV DNA method of Pollicino T. et al. When quantifying ccc DNA HBV in liver tissue of 18 moderately HBV activity with HBV DNA PCR positive results patients and 16 inactive HBsAg carriers, the ccc DNA HBV content was significantly different between groups (p<0.034) and in terms 1 copy of the β-globin gene among moderate activity HBV patients amounted to 1.71±1.32 copies/cell, and for inactive HBsAg carriers 0.15±0.14 copies/cell. In the group of patients with severe liver fibrosis and cirrhosis, the amount of ccc DNA HBV in liver tissue in patients with HBV averaged 2.5±0.4 copies/cell, in patients with HBV + D on average 0.7±0.25 copies/cell, in patients with HCV + HBV co-infection 0.45±0.07 copies/cell, in patients with a preliminary diagnosis of chronic hepatitis C hepatitis, on average 0.12±0.04 copies/cell, in patients with cryptogenic hepatitis 0.2± 0.05 copies/cell. A significant difference was shown between the group of patients with chronic hepatitis B with marked fibrosis and cirrhosis of the liver with other patients groups, except for the group of 18 moderate activity chronic hepatitis B patients. The values of Student's t-test when compared with other groups were respectively: for patients with a HCV preliminary diagnosis t=5,92 p<0,05 f = 19, patients with cryptogenic hepatitis t=5,71 p<0,05 f = 18, with «inactive HBsAg carriage» t=5,55 p<0,05 f = 29, with HCV + HBV co-infection t=5,05 p<0,05 f = 15 and HBV + D co-infection t=3,82 p<0,05 f = 17. The covalently closed circular DNA HBV quantitative assessment method in liver puncture biopsies allows identifying HBsAgnegative chronic viral hepatitis B forms and also reflects the virus replication activity, which, in turn, makes it possible to assume further disease progression and evaluate the antiviral therapy effectiveness.
Collapse
Affiliation(s)
- Yu V Ostankova
- Saint-Petersburg Pasteur Institute, 197191, Saint Petersburg, Russia
| | - A V Semenov
- Saint-Petersburg Pasteur Institute, 197191, Saint Petersburg, Russia.,Saint-Petersburg State Medical University n.a. acad. I.P. Pavlov, 197022, Saint Petersburg, Russia.,North-West State Medical University n.a. I.I. Mechnikov, 191015, Saint Petersburg, Russia
| | - A A Totolian
- Saint-Petersburg Pasteur Institute, 197191, Saint Petersburg, Russia.,Saint-Petersburg State Medical University n.a. acad. I.P. Pavlov, 197022, Saint Petersburg, Russia
| |
Collapse
|
98
|
Occult hepatitis B in kidney transplants recipients and donors from Western Mexico. Int J Infect Dis 2019; 91:17-21. [PMID: 31669141 DOI: 10.1016/j.ijid.2019.10.023] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2019] [Revised: 10/19/2019] [Accepted: 10/21/2019] [Indexed: 12/25/2022] Open
Abstract
BACKGROUND Occult hepatitis B virus infection (OBI) is defined as the presence of hepatitis B virus (HBV) DNA in serum and/or liver from HBsAg-negative subjects. Our aim was to determine OBI frequency in serum and genomic DNA in patients undergoing renal transplant and their cognate donors in a selected population from Western Mexico. METHODS Blood samples were obtained from 94 donors and their cognate recipients (188 participants) before kidney transplantation. Identification of HBV DNA was carried-out by nested (S-region) and semi-nested (Pol-region) PCR in both genomic and serum DNA samples from 188 participants at pre-surgical stage and from a subset of 73 recipients at three-month follow-up. RESULTS HBV-DNA was not detected in either genomic or serum DNA samples from recipients or donors prior to transplantation. After three-months of follow-up, 2 out of 73 (2.7%, 95% CI: 0.9-11.9%) recipients were positive to HBV-DNA (Pol-region) in genomic DNA samples using a high sensitivity Taq DNA polymerase. CONCLUSIONS OBI incidence in recipients of kidney transplant may be higher than previously recognized. Detection of HBV-DNA was higher in genomic DNA than in serum samples using a high sensitivity Taq DNA polymerase. To the best of our knowledge, this is the first report regarding this specific topic in Mexicans.
Collapse
|
99
|
Exonuclease I and III improve the detection efficacy of hepatitis B virus covalently closed circular DNA. Hepatobiliary Pancreat Dis Int 2019; 18:458-463. [PMID: 30522829 DOI: 10.1016/j.hbpd.2018.11.003] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/14/2018] [Accepted: 10/29/2018] [Indexed: 02/05/2023]
Abstract
BACKGROUND Hepatitis B virus covalently closed circular DNA (HBV cccDNA) is an important biomarker of hepatitis B virus infection. However, the current methods are not specific and sensitive. The present study aimed to develop a specific and sensitive assay method for the quantification of HBV cccDNA. METHODS Exonuclease I (Exo I) & Exonuclease III (Exo III) and specific primer probes are used in real-time PCR. The virus particles isolated from peripheral blood mononuclear cells were used as negative control and HBV1.3 recombinant plasmid 3.2 kb circular DNA fragment was used as positive control. The methods of cccDNA detection were evaluated in cell lines, plasmid, animal model, patient serum and liver biopsies. RESULTS A linear range of 101-107 copies/assay using specific primers for HBV cccDNA was established. HBV cccDNA were only detected in cell lines, animal model and liver tissue. It cannot be detected in serum samples. Intrahepatic HBV cccDNA level had good correlation with intrahepatic total HBV DNA level (r = 0.765, P < 0.001). CONCLUSIONS The real-time quantitative PCR is an effective and feasible method for sensitive and specific detection of low copy number of cccDNA. The novel detection method is fast, provides high sensitivity and specificity and can be used in clinical practice.
Collapse
|
100
|
Clinical utility of HBV surface antigen quantification in HBV e antigen-negative chronic HBV infection. Nat Rev Gastroenterol Hepatol 2019; 16:631-641. [PMID: 31477873 DOI: 10.1038/s41575-019-0197-8] [Citation(s) in RCA: 45] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 07/25/2019] [Indexed: 12/17/2022]
Abstract
Chronic hepatitis B virus (HBV) infection is a serious problem owing to its worldwide distribution and potential adverse sequelae that include cirrhosis and/or hepatocellular carcinoma. Current antiviral therapies have much improved outcomes, but few patients achieve the ultimate goal of hepatitis B surface antigen (HBsAg) loss (functional cure). As hepatitis B e antigen (HBeAg)-negative chronic HBV infection is the final phase prior to HBsAg loss, the management of patients in this phase together with quantification of HBsAg has attracted increasing clinical and research interest. This Review integrates the findings from research in HBsAg kinetics and discusses how they might inform our understanding and management of HBeAg-negative chronic HBV infection. Studies have shown that HBsAg levels are highly predictive of the presence of inactive HBV infection and that serial changes in HBsAg levels might predict HBsAg loss within 1-3 years. Data also suggest that quantitative HBsAg monitoring is important during hepatitis flare and antiviral therapy, especially in the timing of the decision to stop therapy and to start off-therapy retreatment. These findings have shed new light on the natural course of HBV infection and might lead to optimization of the management of HBeAg-negative chronic HBV infection and contribute to the paradigm shift from indefinite to finite therapy for patients with HBV infection.
Collapse
|