1
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Seeger C. Biographical Feature: William (Bill) S. Mason. J Virol 2023; 97:e0188222. [PMID: 36622221 PMCID: PMC9888215 DOI: 10.1128/jvi.01882-22] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023] Open
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2
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Mitosis of Hepatitis B virus-infected cells in vitro results in uninfected daughter cells. JHEP Rep 2022; 4:100514. [PMID: 35898957 PMCID: PMC9309680 DOI: 10.1016/j.jhepr.2022.100514] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/13/2022] [Accepted: 05/16/2022] [Indexed: 11/24/2022] Open
Abstract
Background & Aims The chronicity of HBV (and resultant liver disease) is determined by intrahepatic persistence of the HBV covalently closed circular DNA (cccDNA), an episomal form that encodes all viral transcripts. Therefore, cccDNA is a key target for new treatments, with the ultimate therapeutic aim being its complete elimination. Although established cccDNA molecules are known to be stable in resting hepatocytes, we aimed to understand their fate in dividing cells using in vitro models. Methods We infected HepG2-NTCP and HepaRG-NTCP cells with HBV and induced mitosis by passaging cells. We measured cccDNA copy number (by precise PCR assays) and HBV-expressing cells (by immunofluorescence) with wild-type HBV. We used reporter viruses expressing luciferase or RFP to track number of HBV-expressing cells over time after mitosis induction using luciferase assays and live imaging, respectively. Results In all cases, we observed dramatic reductions in cccDNA levels, HBV-positive cell numbers, and cccDNA-dependent protein expression after each round of cell mitosis. The rates of reduction were highly consistent with mathematical models of a complete cccDNA loss in (as opposed to dilution into) daughter cells. Conclusions Our results are concordant with previous animal models of HBV infection and show that HBV persistence can be efficiently overcome by inducing cell mitosis. These results support therapeutic approaches that induce liver turnover (e.g. immune modulators) in addition to direct-acting antiviral therapies to achieve hepatitis B cure. Lay summary Chronic hepatitis B affects 300 million people (killing 884,000 per year) and is incurable. To cure it, we need to clear the HBV genome from the liver. In this study, we looked at how the virus behaves after a cell divides. We found that it completely clears the virus, making 2 new uninfected cells. Our work informs new approaches to develop cures for chronic hepatitis B infections. HBV persists over decades in the liver, leading to chronic inflammation and serious liver disease. Controversy exists over the fate of viral DNA after cell mitosis, which is crucial to understanding viral persistence. We find here that 2 completely uninfected daughter cells are generated when infected cells undergo mitosis. Our results suggest that therapies that induce turnover of infected cells could facilitate the clearance of chronic HBV infection.
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Zheng Y, Xu M, Zeng D, Tong H, Shi Y, Feng Y, Zhang X. In situ analysis of hepatitis B virus (HBV) antigen and DNA in HBV-induced hepatocellular carcinoma. Diagn Pathol 2022; 17:11. [PMID: 35034659 PMCID: PMC8761330 DOI: 10.1186/s13000-022-01194-8] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2021] [Accepted: 01/02/2022] [Indexed: 12/11/2022] Open
Abstract
Aims Hepatitis B Virus (HBV) infection is the major risk factor for hepatocellular carcinoma (HCC) in East Asia. Here we aimed to further investigate the abundance of viral antigen and DNA within HBV-related HCC and surrounding tissues at histological level. Method In addition to routine histopathology, in situ hybridization (ISH) of HBV DNA and immunohistochemistry (IHC) of HBsAg were performed in tissues from 131 HBsAg-positive HCC patients undergoing liver resection. Serum α-fetoprotein together with basic biochemical and immunological parameter was also measured. Results Overall, the ISH of HBV DNA and IHC of HBsAg showed 31.3% and 92.9% positive rate respectively (p < 0.0001). The level of correlation between these two markers was much more significant in tumor (p < 0.0001) than in tumor-surrounding tissue (p = 0.01). HBsAg exhibited a much higher positive rate in tumor-adjacent tissue than in tumor tissue (86.6% versus 29.9%, p < 0.0001) with significantly different staining pattern. By contrast, the positive rate of HBV DNA ISH was comparable in tumor and surrounding tissue (17.6% versus 22.9%, p = 0.36). Yet the HBV DNA signal in tumor tissue showed predominant nuclear localization (87.0%) whereas staining pattern in adjacent tissue was mixed (43.3% nuclear localization, p = 0.0015). Finally, no significant association between intra-tumor HBV DNA/HBsAg positivity and major histological markers (microvascular invasion, tumor differentiation, etc.) or recurrence after surgery was observed. Conclusions These data confirmed the largely integrated state of HBV DNA, weaker expression and altered localization of surface antigen in tumor compared with surrounding tissue. The strikingly different prevalence and localization of HBsAg and HBV DNA reflected the complex and heterogeneous mechanisms leading to HBV-induced tumorigenesis. Supplementary Information The online version contains supplementary material available at 10.1186/s13000-022-01194-8.
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Affiliation(s)
- Ye Zheng
- Shanghai Public Health Clinical Center, Fudan University, Shanghai, China
| | - Mingzhu Xu
- Shanghai Public Health Clinical Center, Fudan University, Shanghai, China
| | - Dong Zeng
- Shanghai Public Health Clinical Center, Fudan University, Shanghai, China
| | - Haitao Tong
- Shanghai Public Health Clinical Center, Fudan University, Shanghai, China
| | - Yuhan Shi
- Shanghai Public Health Clinical Center, Fudan University, Shanghai, China
| | - Yanling Feng
- Shanghai Public Health Clinical Center, Fudan University, Shanghai, China.
| | - Xiaonan Zhang
- Shanghai Public Health Clinical Center, Fudan University, Shanghai, China. .,Centre for Research in Therapeutic Solutions, Faculty of Science and Technology, University of Canberra, Canberra, ACT, Australia.
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Li W, Wei W, Hou F, Xu H, Cui X. The integration model of hepatitis B virus genome in hepatocellular carcinoma cells based on high-throughput long-read sequencing. Genomics 2021; 114:23-30. [PMID: 34843903 DOI: 10.1016/j.ygeno.2021.11.025] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2021] [Revised: 11/16/2021] [Accepted: 11/22/2021] [Indexed: 11/26/2022]
Abstract
HBV integration and function has gradually been expanding. However, the exact mode of HBV integration remains unclear. In our research, the high-throughput long-read sequencing was combined with bioinformatics to study the complete mode of HBV integration in hepatocellular carcinoma (HCC) cells. The results demonstrated that: 1) The HBV insertion sequences of HBV integration events accounted for 49.5% of the total HBV sequences. 2) Short insertion segments with the length of 0-1 kbp accounted for 50% and the long insertion segments (>3 kbp) accounted for 25% of HBV insertion events. 3)There were different HBV insertion length in the breakpoints formed within different regions. 4) The occurrence of HBV integration events was accompanied by more frequent structural variations. 5)Furthermore, multiple HBV integration patterns were confirmed based on complete HBV insertion sequences. Our research not only clarified a variety of perfect HBV integration models but also determined multiple specific features of HBV integration.
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Affiliation(s)
- Weiyang Li
- Jining Medical University, Jining, Shandong 272067, China; Collaborative Innovation Center for Birth Defect Research and Transformation of Shandong Province, Jining Medical University, Jining, Shandong 272067, China.
| | - Wei Wei
- Jining Medical University, Jining, Shandong 272067, China
| | - Fei Hou
- Jining Medical University, Jining, Shandong 272067, China
| | - Hanshi Xu
- Department of Nasopharyngeal Carcinoma, Sun Yat-sen University Cancer Center, Guangzhou, Guangdong 510275, China
| | - Xiaofang Cui
- Jining Medical University, Jining, Shandong 272067, China.
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5
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Martinez MG, Boyd A, Combe E, Testoni B, Zoulim F. Covalently closed circular DNA: The ultimate therapeutic target for curing HBV infections. J Hepatol 2021; 75:706-717. [PMID: 34051332 DOI: 10.1016/j.jhep.2021.05.013] [Citation(s) in RCA: 49] [Impact Index Per Article: 16.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/01/2021] [Revised: 05/03/2021] [Accepted: 05/07/2021] [Indexed: 12/16/2022]
Abstract
Current antiviral therapies, such as pegylated interferon-α and nucleos(t)ide analogues, effectively improve the quality of life of patients with chronic hepatitis B. However, they can only control the infection rather than curing infected hepatocytes. Complete HBV cure is hampered by the lack of therapies that can directly affect the viral minichromosome (in the form of covalently closed circular DNA [cccDNA]). Approaches currently under investigation in early clinical trials are aimed at achieving a functional cure, defined as the loss of HBsAg and undetectable HBV DNA levels in serum. However, achieving a complete HBV cure requires therapies that can directly target the cccDNA pool, either via degradation, lethal mutations or functional silencing. In this review, we discuss cutting-edge technologies that could lead to non-cytolytic direct cccDNA targeting and cure of infected hepatocytes.
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Affiliation(s)
| | - Anders Boyd
- Stichting HIV Monitoring, Amsterdam, the Netherlands; Department of Infectious Diseases, Research and Prevention, Public Health Service of Amsterdam, Amsterdam, the Netherlands
| | - Emmanuel Combe
- INSERM U1052, CNRS UMR-5286, Cancer Research Center of Lyon (CRCL), Lyon, 69008, France
| | - Barbara Testoni
- INSERM U1052, CNRS UMR-5286, Cancer Research Center of Lyon (CRCL), Lyon, 69008, France
| | - Fabien Zoulim
- INSERM U1052, CNRS UMR-5286, Cancer Research Center of Lyon (CRCL), Lyon, 69008, France; University of Lyon, Université Claude- Bernard (UCBL), 69008 Lyon, France; Hospices Civils de Lyon (HCL), 69002 Lyon, France.
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6
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Ghosh S, Chakraborty A, Banerjee S. Persistence of Hepatitis B Virus Infection: A Multi-Faceted Player for Hepatocarcinogenesis. Front Microbiol 2021; 12:678537. [PMID: 34526974 PMCID: PMC8435854 DOI: 10.3389/fmicb.2021.678537] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2021] [Accepted: 07/06/2021] [Indexed: 12/14/2022] Open
Abstract
Hepatitis B virus (HBV) infection has a multi-dimensional effect on the host, which not only alters the dynamics of immune response but also persists in the hepatocytes to predispose oncogenic factors. The virus exists in multiple forms of which the nuclear localized covalently closed circular DNA (cccDNA) is the most stable and the primary reason for viral persistence even after clearance of surface antigen and viral DNA. The second reason is the existence of pregenomic RNA (pgRNA) containing virion particles. On the other hand, the integration of the viral genome in the host chromosome also leads to persistent production of viral proteins along with the chromosomal instabilities. The interferon treatment or administration of nucleot(s)ide analogs leads to reduction in the viral DNA load, but the pgRNA and surface antigen clearance are a slow process and complete loss of serological HBsAg is rare. The prolonged exposure of immune cells to the viral antigens, particularly HBs antigen, in the blood circulation results in T-cell exhaustion, which disrupts immune clearance of the virus and virus-infected cells. In addition, it predisposes immune-tolerant microenvironment, which facilitates the tumor progression. Thus cccDNA, pgRNA, and HBsAg along with the viral DNA could be the therapeutic targets in the early disease stages that may improve the quality of life of chronic hepatitis B patients by impeding the progression of the disease toward hepatocellular carcinoma.
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Affiliation(s)
| | | | - Soma Banerjee
- Centre for Liver Research, School of Digestive and Liver Diseases, Institute of Post Graduate Medical Education and Research, Kolkata, India
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Bousali M, Papatheodoridis G, Paraskevis D, Karamitros T. Hepatitis B Virus DNA Integration, Chronic Infections and Hepatocellular Carcinoma. Microorganisms 2021; 9:1787. [PMID: 34442866 PMCID: PMC8398950 DOI: 10.3390/microorganisms9081787] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2021] [Revised: 08/13/2021] [Accepted: 08/18/2021] [Indexed: 12/16/2022] Open
Abstract
Hepatitis B Virus (HBV) is an Old World virus with a high mutation rate, which puts its origins in Africa alongside the origins of Homo sapiens, and is a member of the Hepadnaviridae family that is characterized by a unique viral replication cycle. It targets human hepatocytes and can lead to chronic HBV infection either after acute infection via horizontal transmission usually during infancy or childhood or via maternal-fetal transmission. HBV has been found in ~85% of HBV-related Hepatocellular Carcinomas (HCC), and it can integrate the whole or part of its genome into the host genomic DNA. The molecular mechanisms involved in the HBV DNA integration is not yet clear; thus, multiple models have been described with respect to either the relaxed-circular DNA (rcDNA) or the double-stranded linear DNA (dslDNA) of HBV. Various genes have been found to be affected by HBV DNA integration, including cell-proliferation-related genes, oncogenes and long non-coding RNA genes (lincRNAs). The present review summarizes the advances in the research of HBV DNA integration, focusing on the evolutionary and molecular side of the integration events along with the arising clinical aspects in the light of WHO's commitment to eliminate HBV and viral hepatitis by 2030.
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Affiliation(s)
- Maria Bousali
- Bioinformatics and Applied Genomics Unit, Department of Microbiology, Hellenic Pasteur Institute, 11521 Athens, Greece;
| | - George Papatheodoridis
- Department of Gastroenterology, “Laiko” General Hospital of Athens, Medical School, National and Kapodistrian University of Athens, 11527 Athens, Greece;
| | - Dimitrios Paraskevis
- Department of Hygiene Epidemiology and Medical Statistics, School of Medicine, National and Kapodistrian University of Athens, 15772 Athens, Greece;
| | - Timokratis Karamitros
- Bioinformatics and Applied Genomics Unit, Department of Microbiology, Hellenic Pasteur Institute, 11521 Athens, Greece;
- Laboratory of Medical Microbiology, Department of Microbiology, Hellenic Pasteur Institute, 11521 Athens, Greece
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8
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Zhang D, Zhang K, Protzer U, Zeng C. HBV Integration Induces Complex Interactions between Host and Viral Genomic Functions at the Insertion Site. J Clin Transl Hepatol 2021; 9:399-408. [PMID: 34221926 PMCID: PMC8237140 DOI: 10.14218/jcth.2021.00062] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/07/2021] [Revised: 03/29/2021] [Accepted: 03/31/2021] [Indexed: 02/06/2023] Open
Abstract
Hepatitis B virus (HBV), one of the well-known DNA oncogenic viruses, is the leading cause of hepatocellular carcinoma (HCC). In infected hepatocytes, HBV DNA can be integrated into the host genome through an insertional mutagenesis process inducing tumorigenesis. Dissection of the genomic features surrounding integration sites will deepen our understanding of mechanisms underlying integration. Moreover, the quantity and biological activity of integration sites may reflect the DNA damage within affected cells or the potential survival benefits they may confer. The well-known human genomic features include repeat elements, particular regions (such as telomeres), and frequently interrupted genes (e.g., telomerase reverse transcriptase [i.e. TERT], lysine methyltransferase 2B [i.e. KMT2B], cyclin E1 [CCNE1], and cyclin A2 [CCNA2]). Consequently, distinct genomic features within diverse integrations differentiate their biological functions. Meanwhile, accumulating evidence has shown that viral proteins produced by integrants may cause cell damage even after the suppression of HBV replication. The integration-derived gene products can also serve as tumor markers, promoting the development of novel therapeutic strategies for HCC. Viral integrants can be single copy or multiple copies of different fragments with complicated rearrangement, which warrants elucidation of the whole viral integrant arrangement in future studies. All of these considerations underlie an urgent need to develop novel methodology and technology for sequence characterization and function evaluation of integration events in chronic hepatitis B-associated disease progression by monitoring both host genomic features and viral integrants. This endeavor may also serve as a promising solution for evaluating the risk of tumorigenesis and as a companion diagnostic for designing therapeutic strategies targeting integration-related disease complications.
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Affiliation(s)
- Dake Zhang
- Beijing Advanced Innovation Centre for Biomedical Engineering, Key Laboratory for Biomechanics and Mechanobiology of Ministry of Education, School of Biological Science and Medical Engineering, Beihang University, Beijing, China
| | - Ke Zhang
- SCG Cell Therapy Pte. Ltd, Singapore
- Institute of Virology, Technical University of Munich/Helmholtz Zentrum München, Munich, Germany
| | - Urlike Protzer
- Institute of Virology, Technical University of Munich/Helmholtz Zentrum München, Munich, Germany
- German Center for Infection Research (DZIF), Munich, Germany
| | - Changqing Zeng
- Key Laboratory of Genomic and Precision Medicine, Beijing Institute of Genomics, Chinese Academy of Sciences, Beijing, China
- University of Chinese Academy of Sciences, Beijing, China
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9
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Suresh M, Menne S. Application of the woodchuck animal model for the treatment of hepatitis B virus-induced liver cancer. World J Gastrointest Oncol 2021; 13:509-535. [PMID: 34163570 PMCID: PMC8204361 DOI: 10.4251/wjgo.v13.i6.509] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/21/2021] [Revised: 05/02/2021] [Accepted: 05/15/2021] [Indexed: 02/06/2023] Open
Abstract
This review describes woodchucks chronically infected with the woodchuck hepatitis virus (WHV) as an animal model for hepatocarcinogenesis and treatment of primary liver cancer or hepatocellular carcinoma (HCC) induced by the hepatitis B virus (HBV). Since laboratory animal models susceptible to HBV infection are limited, woodchucks experimentally infected with WHV, a hepatitis virus closely related to HBV, are increasingly used to enhance our understanding of virus-host interactions, immune response, and liver disease progression. A correlation of severe liver pathogenesis with high-level viral replication and deficient antiviral immunity has been established, which are present during chronic infection after WHV inoculation of neonatal woodchucks for modeling vertical HBV transmission in humans. HCC in chronic carrier woodchucks develops 17 to 36 mo after neonatal WHV infection and involves liver tumors that are comparable in size, morphology, and molecular gene signature to those of HBV-infected patients. Accordingly, woodchucks with WHV-induced liver tumors have been used for the improvement of imaging and ablation techniques of human HCC. In addition, drug efficacy studies in woodchucks with chronic WHV infection have revealed that prolonged treatment with nucleos(t)ide analogs, alone or in combination with other compounds, minimizes the risk of liver disease progression to HCC. More recently, woodchucks have been utilized in the delineation of mechanisms involved in innate and adaptive immune responses against WHV during acute, self-limited and chronic infections. Therapeutic interventions based on modulating the deficient host antiviral immunity have been explored in woodchucks for inducing functional cure in HBV-infected patients and for reducing or even delaying associated liver disease sequelae, including the onset of HCC. Therefore, woodchucks with chronic WHV infection constitute a well-characterized, fully immunocompetent animal model for HBV-induced liver cancer and for preclinical evaluation of the safety and efficacy of new modalities, which are based on chemo, gene, and immune therapy, for the prevention and treatment of HCC in patients for which current treatment options are dismal.
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Affiliation(s)
- Manasa Suresh
- Department of Microbiology and Immunology, Georgetown University Medical Center, Washington, DC 20057, United States
| | - Stephan Menne
- Department of Microbiology and Immunology, Georgetown University Medical Center, Washington, DC 20057, United States
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10
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Hepatitis B Virus DNA Integration and Clonal Expansion of Hepatocytes in the Chronically Infected Liver. Viruses 2021; 13:v13020210. [PMID: 33573130 PMCID: PMC7911963 DOI: 10.3390/v13020210] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2021] [Revised: 01/19/2021] [Accepted: 01/21/2021] [Indexed: 02/07/2023] Open
Abstract
Human hepatitis B virus (HBV) can cause chronic, lifelong infection of the liver that may lead to persistent or episodic immune-mediated inflammation against virus-infected hepatocytes. This immune response results in elevated rates of killing of virus-infected hepatocytes, which may extend over many years or decades, lead to fibrosis and cirrhosis, and play a role in the high incidence of hepatocellular carcinoma (HCC) in HBV carriers. Immune-mediated inflammation appears to cause oxidative DNA damage to hepatocytes, which may also play a major role in hepatocarcinogenesis. An additional DNA damaging feature of chronic infections is random integration of HBV DNA into the chromosomal DNA of hepatocytes. While HBV DNA integration does not have a role in virus replication it may alter gene expression of the host cell. Indeed, most HCCs that arise in HBV carriers contain integrated HBV DNA and, in many, the integrant appears to have played a role in hepatocarcinogenesis. Clonal expansion of hepatocytes, which is a natural feature of liver biology, occurs because the hepatocyte population is self-renewing and therefore loses complexity due to random hepatocyte death and replacement by proliferation of surviving hepatocytes. This process may also represent a risk factor for the development of HCC. Interestingly, during chronic HBV infection, hepatocyte clones detected using integrated HBV DNA as lineage-specific markers, emerge that are larger than those expected to occur by random death and proliferation of hepatocytes. The emergence of these larger hepatocyte clones may reflect a survival advantage that could be explained by an ability to avoid the host immune response. While most of these larger hepatocyte clones are probably not preneoplastic, some may have already acquired preneoplastic changes. Thus, chronic inflammation in the HBV-infected liver may be responsible, at least in part, for both initiation of HCC via oxidative DNA damage and promotion of HCC via stimulation of hepatocyte proliferation through immune-mediated killing and compensatory division.
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11
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Huang Q, Zhou B, Cai D, Zong Y, Wu Y, Liu S, Mercier A, Guo H, Hou J, Colonno R, Sun J. Rapid Turnover of Hepatitis B Virus Covalently Closed Circular DNA Indicated by Monitoring Emergence and Reversion of Signature-Mutation in Treated Chronic Hepatitis B Patients. Hepatology 2021; 73:41-52. [PMID: 32189364 PMCID: PMC7898704 DOI: 10.1002/hep.31240] [Citation(s) in RCA: 52] [Impact Index Per Article: 17.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/20/2019] [Revised: 02/07/2020] [Accepted: 03/10/2020] [Indexed: 12/12/2022]
Abstract
BACKGROUND AND AIMS Hepatitis B virus (HBV) covalently closed circular DNA (cccDNA) plays a pivotal role in the establishment and persistence of HBV infection. Understanding the turnover time of preexisting cccDNA pools would be helpful in designing strategies to clear HBV by fully blocking the de novo generation of cccDNA. APPROACH AND RESULTS In this study, we retrospectively monitored the emergence and reversion of the rtM204I/V mutant, a signature lamivudine resistance (LAMR ) mutation serving as a biomarker of cccDNA turnover in liver biopsies and longitudinal serum samples from two clinical trials. Methodologies were optimized to differentially isolate and sequence HBV virion DNA, cccDNA, and HBV RNA from clinical samples. A strong correlation was observed between LAMR composition of cccDNA with that of serum and intrahepatic HBV RNA in paired liver and serum samples (r = 0.96 and 0.90, respectively), suggesting that serum HBV RNA can serve as a surrogate marker of cccDNA genetic composition when liver biopsies are unavailable. LAMR mutations emerged and increased from undetectable to 40%-90% within 16-28 weeks in serum HBV RNA from telbivudine-treated patients experiencing virological breakthrough. Similarly, in lamivudine-resistant patients who switched to interferon therapy, serum HBV-RNA population bearing 100% LAMR mutations fully reversed back to wild type within 24-48 weeks. CONCLUSIONS The genetic composition dynamics of serum HBV RNA and biopsy cccDNA in treated HBV patients indicates that cccDNA turnover occurs relatively rapidly (several months), offering a possibility of HBV cure with finite therapy through completely blocking cccDNA replenishment.
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Affiliation(s)
- Qi Huang
- Assembly Biosciences, Inc.South San FranciscoCA
| | - Bin Zhou
- State Key Laboratory of Organ Failure ResearchGuangdong Provincial Key Laboratory of Viral Hepatitis ResearchDepartment of Infectious DiseasesNanfang HospitalSouthern Medical UniversityGuangzhouChina
- Department of Microbiology and ImmunologyIndiana UniversityIndianapolisIN
| | - Dawei Cai
- Assembly Biosciences, Inc.South San FranciscoCA
| | - Yuhua Zong
- Assembly Biosciences, Inc.South San FranciscoCA
| | - Yaobo Wu
- State Key Laboratory of Organ Failure ResearchGuangdong Provincial Key Laboratory of Viral Hepatitis ResearchDepartment of Infectious DiseasesNanfang HospitalSouthern Medical UniversityGuangzhouChina
| | - Shi Liu
- State Key Laboratory of Organ Failure ResearchGuangdong Provincial Key Laboratory of Viral Hepatitis ResearchDepartment of Infectious DiseasesNanfang HospitalSouthern Medical UniversityGuangzhouChina
| | | | - Haitao Guo
- Department of Microbiology and ImmunologyIndiana UniversityIndianapolisIN
- Cancer Virology ProgramUPMC Hillman Cancer CenterDepartment of Microbiology and Molecular GeneticsUniversity of PittsburghPittsburghPA
| | - Jinlin Hou
- State Key Laboratory of Organ Failure ResearchGuangdong Provincial Key Laboratory of Viral Hepatitis ResearchDepartment of Infectious DiseasesNanfang HospitalSouthern Medical UniversityGuangzhouChina
| | | | - Jian Sun
- State Key Laboratory of Organ Failure ResearchGuangdong Provincial Key Laboratory of Viral Hepatitis ResearchDepartment of Infectious DiseasesNanfang HospitalSouthern Medical UniversityGuangzhouChina
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12
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Kang B, Yi DY, Choe BH. Translational Strategies to Eliminate Chronic Hepatitis B in Children: Prophylaxis and Management in East Asian Countries. Front Pediatr 2021; 9:809838. [PMID: 35186829 PMCID: PMC8854863 DOI: 10.3389/fped.2021.809838] [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] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/05/2021] [Accepted: 12/27/2021] [Indexed: 12/14/2022] Open
Abstract
Translational medical research on hepatitis B virus (HBV) infection and chronic hepatitis B (CHB) pathogenesis provides guidance on strengthening the treatment and prevention strategies of CHB. Preventing vertical transmission is the key to eliminating HBV infection in children. The understanding of HBV replication, hepatocyte turnover, and the fate of covalently closed circular DNA (cccDNA) would help establish a personalized application of the guidelines, especially concerning the discontinuation of nucleos(t)ide analog (NA) treatment in children. Transplacental leakage of HBV-infected maternal blood is suggested as the leading cause of vertical transmission. Prenatal maternal prophylaxis could diminish maternal HBV viremia at delivery, to reduce the risk of neonatal HBV infection. The meaning of the expression "no additional risk of breast milk feeding" is thereby explained. Understanding the untreated natural course of CHB in children and the course changeable by treatment is important to apply individualistic strategies and avoid the immoral selection of treatment indications. NAs with potent efficacy and a high barrier to drug resistance should be used as first-line treatment to reduce the likelihood of NA-resistant HBV development because the rate of mutant HBV emergence might count on the infected hepatocyte turnover rate in chronic HBV infection. Although elimination of intranuclear cccDNA is difficult by NAs alone, a cure is possible by human immunity and hepatocyte turnover. The reduction of intranuclear cccDNA occurs after the destruction of HBV-infected hepatocytes, non-cytolytic immune response, apoptosis of hepatocytes, and compensatory cell proliferation. Therefore, consolidation therapy after NA-induced hepatitis B e-antigen seroconversion must be necessary for a sufficient period. This review also summarizes the treatment strategies of CHB in children based on the practical application of translational research.
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Affiliation(s)
- Ben Kang
- Department of Pediatrics, School of Medicine, Kyungpook National University, Daegu, South Korea
| | - Dae Yong Yi
- Department of Pediatrics, College of Medicine, Chung-Ang University Hospital, Chung-Ang University, Seoul, South Korea
| | - Byung-Ho Choe
- Department of Pediatrics, School of Medicine, Kyungpook National University, Daegu, South Korea
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Kim M, Powers CA, Curtin LI, Fisher DT, Sexton S, Gurova KV, Skitzki JJ, Iyer RV. A Translational Hepatic Artery Infusion (HAI) Model for Hepatocellular Carcinoma in Woodchucks. J Surg Res 2020; 251:126-136. [PMID: 32143057 DOI: 10.1016/j.jss.2020.02.002] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2019] [Revised: 01/03/2020] [Accepted: 02/01/2020] [Indexed: 12/20/2022]
Abstract
BACKGROUND Woodchucks (Marmota monax) are a well-accepted animal model for the investigation of spontaneous hepatocellular carcinoma (HCC). As HCC tumors obtain nutrient blood supply exclusively from the hepatic artery, hepatic artery infusion (HAI) has been applied to HCC. However, there is a scarcity of experimental animal models to standardize drug regimens and examine novel agents. The purpose of this study was to establish an HAI model in woodchucks. MATERIALS AND METHODS HAI ports were placed in the gastroduodenal artery (GDA) of 11 woodchucks. The ports were infused with either a vehicle (dextrose 5% in water) or an experimental drug, CBL0137, once a week for 3 wk. Technical success rates, anatomical variation, morbidity and mortality, and tumor responses between groups were analyzed. RESULTS The GDA access was feasible and reproducible in all woodchucks (11/11). The average operation time was 95 ± 20 min with no increase in the levels of liver enzymes detected from either infusate. The most common morbidity of CBL0137 therapy was anorexia after surgery. One woodchuck died due to hemorrhage at the gallbladder removal site from hepatic coagulopathy. Significantly higher CBL0137 concentrations were measured in the liver compared with blood after each HAI. Tumor growth was suppressed after multiple CBL0137 HAI treatments which corresponded to greater T cell infiltration and increased tumor cell apoptosis. CONCLUSIONS HAI via GDA was a feasible and reproducible approach with low morbidity and mortality in woodchucks. The described techniques serve as a reliable platform for the identification and characterization of therapeutics for HCC.
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Affiliation(s)
- Minhyung Kim
- Department of Surgical Oncology, Roswell Park Comprehensive Cancer Center, Buffalo, New York; Department of Immunology, Roswell Park Comprehensive Cancer Center, Buffalo, New York
| | - Colin A Powers
- Department of Surgical Oncology, Roswell Park Comprehensive Cancer Center, Buffalo, New York
| | - Leslie I Curtin
- Laboratory Animal Shared Resources, Roswell Park Comprehensive Cancer Center, Buffalo, New York
| | - Daniel T Fisher
- Department of Surgical Oncology, Roswell Park Comprehensive Cancer Center, Buffalo, New York; Department of Immunology, Roswell Park Comprehensive Cancer Center, Buffalo, New York
| | - Sandra Sexton
- Laboratory Animal Shared Resources, Roswell Park Comprehensive Cancer Center, Buffalo, New York
| | - Katerina V Gurova
- Department of Cell Stress Biology, Roswell Park Comprehensive Cancer Center, Buffalo, New York
| | - Joseph J Skitzki
- Department of Surgical Oncology, Roswell Park Comprehensive Cancer Center, Buffalo, New York; Department of Immunology, Roswell Park Comprehensive Cancer Center, Buffalo, New York
| | - Renuka V Iyer
- Department of Internal Medicine, Roswell Park Comprehensive Cancer Center, Buffalo, New York.
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14
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Ruan P, Dai X, Sun J, He C, Huang C, Zhou R, Chemin I. Integration of hepatitis B virus DNA into p21-activated kinase 3 (PAK3) gene in HepG2.2.15 cells. Virus Genes 2020; 56:168-173. [PMID: 31897927 DOI: 10.1007/s11262-019-01725-4] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2019] [Accepted: 12/16/2019] [Indexed: 02/06/2023]
Abstract
Integration of HBV DNA into host chromosomes was found in most of the patients with chronic hepatitis B (CHB). In this study, using inverse nested PCR (invPCR), we found the integration site chrX: 111,009,033, which inserted into the p21-activated kinase 3 (PAK3) gene in HepG2.2.15 cells. The viral-human chimeric transcripts were also observed and, significant differences of the copy numbers of integration site chrX: 111,009,033 (P = 0.012) and intra-cell HBV DNA levels (P = 0.027) were found between the cells with and without H2O2 treatment, respectively. This study may provide a novel insight into the elucidation of etiology of HBV integration.
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Affiliation(s)
- Peng Ruan
- Department of Gastroenterology, Renmin Hospital of Wuhan University, 238 Jiefang Road, Wuhan, 430060, Hubei, People's Republic of China. .,Department of Breast Surgery, Renmin Hospital, Hubei University of Medicine, Shiyan, 442000, Hubei, People's Republic of China. .,INSERM U1052, CNRS UMR5286, Centre de Recherche en Cancérologie, Université Claude Bernard, Lyon, France.
| | - Xiufang Dai
- Department of Breast Surgery, Renmin Hospital, Hubei University of Medicine, Shiyan, 442000, Hubei, People's Republic of China
| | - Jun Sun
- Department of Gastroenterology, Renmin Hospital of Wuhan University, 238 Jiefang Road, Wuhan, 430060, Hubei, People's Republic of China
| | - Chunping He
- Department of Gastroenterology, Renmin Hospital of Wuhan University, 238 Jiefang Road, Wuhan, 430060, Hubei, People's Republic of China
| | - Chao Huang
- Department of Gastroenterology, Renmin Hospital of Wuhan University, 238 Jiefang Road, Wuhan, 430060, Hubei, People's Republic of China
| | - Rui Zhou
- Department of Gastroenterology, Renmin Hospital of Wuhan University, 238 Jiefang Road, Wuhan, 430060, Hubei, People's Republic of China
| | - Isabelle Chemin
- INSERM U1052, CNRS UMR5286, Centre de Recherche en Cancérologie, Université Claude Bernard, Lyon, France.
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15
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Testoni B, Lebossé F, Scholtes C, Berby F, Miaglia C, Subic M, Loglio A, Facchetti F, Lampertico P, Levrero M, Zoulim F. Serum hepatitis B core-related antigen (HBcrAg) correlates with covalently closed circular DNA transcriptional activity in chronic hepatitis B patients. J Hepatol 2019; 70:615-625. [PMID: 30529504 DOI: 10.1016/j.jhep.2018.11.030] [Citation(s) in RCA: 173] [Impact Index Per Article: 34.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/14/2018] [Revised: 11/28/2018] [Accepted: 11/29/2018] [Indexed: 12/14/2022]
Abstract
BACKGROUND & AIMS It has been proposed that serum hepatitis B core-related antigen (HBcrAg) reflects intrahepatic covalently closed circular (ccc)DNA levels. However, the correlation of HBcrAg with serum and intrahepatic viral markers and liver histology has not been comprehensively investigated in a large sample. We aimed to determine if HBcrAg could be a useful therapeutic marker in patients with chronic hepatitis B. METHODS HBcrAg was measured by chemiluminescent enzyme immunoassay in 130 (36 hepatitis B e antigen [HBeAg]+ and 94 HBeAg-) biopsy proven, untreated, patients with chronic hepatitis B. HBcrAg levels were correlated with: a) serum hepatitis B virus (HBV)-DNA, quantitative hepatitis B surface antigen and alanine aminotransferase levels; b) intrahepatic total (t)HBV-DNA, cccDNA, pregenomic (pg)RNA and cccDNA transcriptional activity (defined as pgRNA/cccDNA ratio); c) fibrosis and necroinflammatory activity scores. RESULTS HBcrAg levels were significantly higher in HBeAg+ vs. HBeAg- patients and correlated with serum HBV-DNA, intrahepatic tHBV-DNA, pgRNA and cccDNA levels, and transcriptional activity. Patients who were negative for HBcrAg (<3 LogU/ml) had less liver cccDNA and lower cccDNA activity than the HBcrAg+ group. Principal component analysis coupled with unsupervised clustering identified that in a subgroup of HBeAg- patients, higher HBcrAg levels were associated with higher serum HBV-DNA, intrahepatic tHBV-DNA, pgRNA, cccDNA transcriptional activity and with higher fibrosis and necroinflammatory activity scores. CONCLUSIONS Our results indicate that HBcrAg is a surrogate marker of both intrahepatic cccDNA and its transcriptional activity. HBcrAg could be useful in the evaluation of new antiviral therapies aiming at a functional cure of HBV infection either by directly or indirectly targeting the intrahepatic cccDNA pool. LAY SUMMARY Hepatitis B virus causes a chronic infection which develops into severe liver disease and liver cancer. The viral covalently closed circular DNA (cccDNA) is responsible for the persistence of the infection in hepatocytes. To better manage patient treatment and follow-up, and to develop new antiviral treatments directly targeting the intrahepatic pool of cccDNA, serum surrogate markers reflecting the viral activity in the liver are urgently needed. In this work, we demonstrate that quantification of hepatitis B core-related antigen in serum correlates with cccDNA amount and activity and could be used to monitor disease progression.
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Affiliation(s)
- Barbara Testoni
- INSERM U1052-Cancer Research Center of Lyon (CRCL), 69008 Lyon, France; University of Lyon, UMR_S1052, CRCL, 69008 Lyon, France
| | - Fanny Lebossé
- INSERM U1052-Cancer Research Center of Lyon (CRCL), 69008 Lyon, France; University of Lyon, UMR_S1052, CRCL, 69008 Lyon, France; Department of Hepatology, Croix Rousse Hospital, Hospices Civils de Lyon, France
| | - Caroline Scholtes
- INSERM U1052-Cancer Research Center of Lyon (CRCL), 69008 Lyon, France; University of Lyon, UMR_S1052, CRCL, 69008 Lyon, France; Department of Virology, Croix Rousse Hospital, Hospices Civils de Lyon, France
| | - Françoise Berby
- INSERM U1052-Cancer Research Center of Lyon (CRCL), 69008 Lyon, France
| | - Clothilde Miaglia
- INSERM U1052-Cancer Research Center of Lyon (CRCL), 69008 Lyon, France; University of Lyon, UMR_S1052, CRCL, 69008 Lyon, France; Department of Hepatology, Croix Rousse Hospital, Hospices Civils de Lyon, France
| | - Miroslava Subic
- Department of Hepatology, Croix Rousse Hospital, Hospices Civils de Lyon, France
| | - Alessandro Loglio
- Division of Gastroenterology and Hepatology, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Università degli Studi di Milano, Milan, Italy
| | - Floriana Facchetti
- Division of Gastroenterology and Hepatology, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Università degli Studi di Milano, Milan, Italy
| | - Pietro Lampertico
- Division of Gastroenterology and Hepatology, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Università degli Studi di Milano, Milan, Italy
| | - Massimo Levrero
- INSERM U1052-Cancer Research Center of Lyon (CRCL), 69008 Lyon, France; University of Lyon, UMR_S1052, CRCL, 69008 Lyon, France; Department of Hepatology, Croix Rousse Hospital, Hospices Civils de Lyon, France; Department of Internal Medicine - DMISM and the IIT Center for Life Nanoscience (CLNS), Sapienza University, Rome, Italy
| | - Fabien Zoulim
- INSERM U1052-Cancer Research Center of Lyon (CRCL), 69008 Lyon, France; University of Lyon, UMR_S1052, CRCL, 69008 Lyon, France; Department of Hepatology, Croix Rousse Hospital, Hospices Civils de Lyon, France.
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16
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Caballero A, Tabernero D, Buti M, Rodriguez-Frias F. Hepatitis B virus: The challenge of an ancient virus with multiple faces and a remarkable replication strategy. Antiviral Res 2018; 158:34-44. [PMID: 30059722 DOI: 10.1016/j.antiviral.2018.07.019] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2017] [Revised: 07/24/2018] [Accepted: 07/26/2018] [Indexed: 02/07/2023]
Abstract
The hepatitis B virus (HBV) is the prototype member of the Hepadnaviridae, an ancient family of hepatotropic DNA viruses, which may have originated from 360 to 430 million years ago and with evidence of endogenization in reptilian genomes >200 million years ago. The virus is currently estimated to infect more than 250 million humans. The extremely successful spread of this pathogen among the human population is explained by its multiple particulate forms, effective transmission strategies (particularly perinatal transmission), long induction period and low associated mortality. These characteristics confer selective advantages, enabling the virus to persist in small, disperse populations and spread worldwide, with high prevalence rates in many countries. The HBV replication strategy is remarkably complex and includes a multiplicity of particulate structures. In addition to the common virions containing DNA in a relaxed circular (rcDNA) or double-stranded linear (dslDNA) forms, the viral population includes virion-like particles containing RNA or "empty" (viral envelopes and capsids without genomes), subviral particles (only an envelope) and even naked capsids. Consequently, several forms of the genome coexist in a single infection: (i) the "traveler" forms found in serum, including rcDNA and dslDNA, which originate from retrotranscription of a messenger RNA (the pregenomic RNA, another form of the viral genome itself) and (ii) forms confined to the host cell nucleus, including covalently closed circular DNA (cccDNA), which leads to a minichromosome form associated with histones and viral proteins, and double-stranded DNA integrated into the host genome. This complex composition lends HBV a kind of "multiple personality". Are these additional particles and genomic forms simple intermediaries/artifacts or do they play a role in the viral life cycle?
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Affiliation(s)
- Andrea Caballero
- Liver Pathology Unit, Departments of Biochemistry and Microbiology, Hospital Universitari Vall d'Hebron and Universitat Autònoma de Barcelona (UAB), 119-129 Passeig Vall d'Hebron, Clinical Laboratories, 08035 Barcelona, Spain.
| | - David Tabernero
- Liver Pathology Unit, Departments of Biochemistry and Microbiology, Hospital Universitari Vall d'Hebron and Universitat Autònoma de Barcelona (UAB), 119-129 Passeig Vall d'Hebron, Clinical Laboratories, 08035 Barcelona, Spain; Centro de Investigación Biomédica en Red de Enfermedades Hepáticas y Digestivas (CIBERehd), Instituto de Salud Carlos III, 3-5 Avenida Monforte de Lemos, pavilion 11, 28029 Madrid, Spain.
| | - Maria Buti
- Centro de Investigación Biomédica en Red de Enfermedades Hepáticas y Digestivas (CIBERehd), Instituto de Salud Carlos III, 3-5 Avenida Monforte de Lemos, pavilion 11, 28029 Madrid, Spain; Liver Unit, Department of Internal Medicine, Hospital Universitari Vall d'Hebron and Universitat Autònoma de Barcelona (UAB), 119-129 Passeig Vall d'Hebron, General Hospital, Internal Medicine 2, 08035 Barcelona, Spain.
| | - Francisco Rodriguez-Frias
- Liver Pathology Unit, Departments of Biochemistry and Microbiology, Hospital Universitari Vall d'Hebron and Universitat Autònoma de Barcelona (UAB), 119-129 Passeig Vall d'Hebron, Clinical Laboratories, 08035 Barcelona, Spain; Centro de Investigación Biomédica en Red de Enfermedades Hepáticas y Digestivas (CIBERehd), Instituto de Salud Carlos III, 3-5 Avenida Monforte de Lemos, pavilion 11, 28029 Madrid, Spain.
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17
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Sequence analysis of integrated hepatitis B virus DNA during HBeAg-seroconversion. Emerg Microbes Infect 2018; 7:142. [PMID: 30087321 PMCID: PMC6081408 DOI: 10.1038/s41426-018-0145-7] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2018] [Revised: 07/07/2018] [Accepted: 07/10/2018] [Indexed: 02/07/2023]
Abstract
Hepatitis B virus (HBV) integration into the host cell genome occurs early on in infection and reportedly induces pro-oncogenic changes in hepatocytes that drive HCC initiation. However, it remains unclear when these changes occur during hepatocarcinogenesis. Extensive expansion of hepatocyte clones with a selective advantage was shown to occur prior to cancer formation during the HBeAg-seroconversion phase of chronic HBV infection. We hypothesized that since integrations occur during the early stages of infection, cell phenotype could be altered and induce a selection advantage (e.g., through insertional mutagenesis or cis-mediated activation of downstream genes). Here, we analyzed the enrichment of genomic and functional patterns in the cellular host sequence adjacent to HBV DNA integration events. We examined 717 unique integration events detected in patients who have and have not undergone HBeAg-seroconversion (n = 41) or in an in vitro model system. We also used an in silico model to control for detection biases. We showed that the sites of HBV DNA integration were distributed throughout the entire host genome without obvious enrichment of specific structural or functional genomic features in the adjacent cellular genome during HBeAg-seroconversion. Currently, this is the most comprehensive characterization of HBV DNA integration events prior to hepatocarcinogenesis. Our results suggest no significant selection for (or against) specific cellular sites of HBV DNA integration occur during the clonal expansion phase of chronic HBV infection. Thus, HBV DNA integration events likely represent passenger events rather than active drivers of liver cancer, which was previously suggested.
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18
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Budzinska MA, Shackel NA, Urban S, Tu T. Cellular Genomic Sites of Hepatitis B Virus DNA Integration. Genes (Basel) 2018; 9:E365. [PMID: 30037029 PMCID: PMC6071206 DOI: 10.3390/genes9070365] [Citation(s) in RCA: 41] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2018] [Revised: 07/12/2018] [Accepted: 07/12/2018] [Indexed: 12/14/2022] Open
Abstract
Infection with the Hepatitis B Virus (HBV) is one of the strongest risk-factors for liver cancer (hepatocellular carcinoma, HCC). One of the reported drivers of HCC is the integration of HBV DNA into the host cell genome, which may induce pro-carcinogenic pathways. These reported pathways include: induction of chromosomal instability; generation of insertional mutagenesis in key cancer-associated genes; transcription of downstream cancer-associated cellular genes; and/or formation of a persistent source of viral protein expression (particularly HBV surface and X proteins). The contribution of each of these specific mechanisms towards carcinogenesis is currently unclear. Here, we review the current knowledge of specific sites of HBV DNA integration into the host genome, which sheds light on these mechanisms. We give an overview of previously-used methods to detect HBV DNA integration and the enrichment of integration events in specific functional and structural cellular genomic sites. Finally, we posit a theoretical model of HBV DNA integration during disease progression and highlight open questions in the field.
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Affiliation(s)
| | - Nicholas A Shackel
- Centenary Institute, University of Sydney, Sydney NSW 2050, Australia.
- South Western Sydney Clinical School, University of New South Wales, Liverpool NSW 2170, Australia.
- Gastroenterology, Liverpool Hospital, Liverpool NSW 2170, Australia.
| | - Stephan Urban
- Department of Infectious Diseases, Molecular Virology, Heidelberg Hospital University, D-69120 Heidelberg, Germany.
- German Center for Infection Research (DZIF), Partner Site Heidelberg, D-69120 Heidelberg, Germany.
| | - Thomas Tu
- Department of Infectious Diseases, Molecular Virology, Heidelberg Hospital University, D-69120 Heidelberg, Germany.
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19
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Anikhindi SA, Kumar A, Sharma P, Singla V, Bansal N, Arora A. Ideal Cure for Hepatitis B Infection: The Target is in Sight. J Clin Exp Hepatol 2018; 8:188-194. [PMID: 29892183 PMCID: PMC5992304 DOI: 10.1016/j.jceh.2017.10.002] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/20/2017] [Accepted: 10/30/2017] [Indexed: 12/12/2022] Open
Abstract
Hepatitis B virus (HBV) is one of the most common causes of liver cirrhosis and hepatocellular carcinoma. Despite recent strides in pharmacotherapy, complete cure of HBV infection still remains an enigma. The biggest obstacle in HBV therapy is clearance of covalently closed circular deoxyribonucleic acid (cccDNA). We discuss about the role of cccDNA in HBV life cycle, efficacy and shortcomings of currently available antivirals as well as promising novel targets to achieve ideal HBV cure.
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Affiliation(s)
- Shrihari A. Anikhindi
- Department of Gastroenterology, Sir Ganga Ram Hospital, New Delhi, India
- Department of Pathology, Sir Ganga Ram Hospital, New Delhi, India
| | - Ashish Kumar
- Department of Gastroenterology, Sir Ganga Ram Hospital, New Delhi, India
- Department of Pathology, Sir Ganga Ram Hospital, New Delhi, India
| | - Praveen Sharma
- Department of Gastroenterology, Sir Ganga Ram Hospital, New Delhi, India
- Department of Pathology, Sir Ganga Ram Hospital, New Delhi, India
| | - Vikas Singla
- Department of Gastroenterology, Sir Ganga Ram Hospital, New Delhi, India
- Department of Pathology, Sir Ganga Ram Hospital, New Delhi, India
| | - Naresh Bansal
- Department of Gastroenterology, Sir Ganga Ram Hospital, New Delhi, India
- Department of Pathology, Sir Ganga Ram Hospital, New Delhi, India
| | - Anil Arora
- Department of Gastroenterology, Sir Ganga Ram Hospital, New Delhi, India
- Department of Pathology, Sir Ganga Ram Hospital, New Delhi, India
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20
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Hepatitis B Virus DNA Integration Occurs Early in the Viral Life Cycle in an In Vitro Infection Model via Sodium Taurocholate Cotransporting Polypeptide-Dependent Uptake of Enveloped Virus Particles. J Virol 2018; 92:JVI.02007-17. [PMID: 29437961 DOI: 10.1128/jvi.02007-17] [Citation(s) in RCA: 111] [Impact Index Per Article: 18.5] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2017] [Accepted: 01/30/2018] [Indexed: 02/08/2023] Open
Abstract
Chronic infection by hepatitis B virus (HBV) is the major contributor to liver disease worldwide. Though HBV replicates via a nuclear episomal DNA (covalently closed circular DNA [cccDNA]), integration of HBV DNA into the host cell genome is regularly observed in the liver in infected patients. While reported as a prooncogenic alteration, the mechanism(s) and timing of HBV DNA integration are not well understood, chiefly due to the lack of in vitro infection models that have detectable integration events. In this study, we have established an in vitro system in which integration can be reliably detected following HBV infection. We measured HBV DNA integration using inverse nested PCR in primary human hepatocytes, HepaRG-NTCP, HepG2-NTCP, and Huh7-NTCP cells after HBV infection. Integration was detected in all cell types at a rate of >1 per 10,000 cells, with the most consistent detection in Huh7-NTCP cells. The integration rate remained stable between 3 and 9 days postinfection. HBV DNA integration was efficiently blocked by treatment with a 200 nM concentration of the HBV entry inhibitor Myrcludex B, but not with 10 μM tenofovir, 100 U of interferon alpha, or a 1 μM concentration of the capsid assembly inhibitor GLS4. This suggests that integration of HBV DNA occurs immediately after infection of hepatocytes and is likely independent of de novo HBV genome replication in this model. Site analysis revealed that HBV DNA integrations were distributed over the entire human genome. Further, integrated HBV DNA sequences were consistent with double-stranded linear HBV DNA being the major precursor. Thus, we have established an in vitro system to interrogate the mechanisms of HBV DNA integration.IMPORTANCE Hepatitis B virus (HBV) is a common blood-borne pathogen and, following a chronic infection, can cause liver cancer and liver cirrhosis. Integration of HBV DNA into the host genome occurs in all known members of the Hepadnaviridae family, despite this form not being necessary for viral replication. HBV DNA integration has been reported to drive liver cancer formation and persistence of virus infection. However, when and the mechanism(s) by which HBV DNA integration occurs are not clear. In this study, we have developed and characterized an in vitro system to reliably detect HBV DNA integrations that result from a true HBV infection event and that closely resemble those found in patient tissues. Using this model, we showed that integration occurs when the infection is first established. Importantly, we provide here a system to analyze molecular factors involved in HBV integration, which can be used to develop strategies to halt its formation.
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21
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Allweiss L, Volz T, Giersch K, Kah J, Raffa G, Petersen J, Lohse AW, Beninati C, Pollicino T, Urban S, Lütgehetmann M, Dandri M. Proliferation of primary human hepatocytes and prevention of hepatitis B virus reinfection efficiently deplete nuclear cccDNA in vivo. Gut 2018; 67:542-552. [PMID: 28428345 DOI: 10.1136/gutjnl-2016-312162] [Citation(s) in RCA: 108] [Impact Index Per Article: 18.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/29/2016] [Revised: 03/30/2017] [Accepted: 03/31/2017] [Indexed: 12/12/2022]
Abstract
OBJECTIVE The stability of the covalently closed circular DNA (cccDNA) in nuclei of non-dividing hepatocytes represents a key determinant of HBV persistence. Contrarily, studies with animal hepadnaviruses indicated that hepatocyte turnover can reduce cccDNA loads but knowledge on the proliferative capacity of HBV-infected primary human hepatocytes (PHHs) in vivo and the fate of cccDNA in dividing PHHs is still lacking. This study aimed to determine the impact of human hepatocyte division on cccDNA stability in vivo. METHODS PHH proliferation was triggered by serially transplanting hepatocytes from HBV-infected humanised mice into naïve recipients. Cell proliferation and virological changes were assessed by quantitative PCR, immunofluorescence and RNA in situ hybridisation. Viral integrations were analysed by gel separation and deep sequencing. RESULTS PHH proliferation strongly reduced all infection markers, including cccDNA (median 2.4 log/PHH). Remarkably, cell division appeared to cause cccDNA dilution among daughter cells and intrahepatic cccDNA loss. Nevertheless, HBV survived in sporadic non-proliferating human hepatocytes, so that virological markers rebounded as hepatocyte expansion relented. This was due to reinfection of quiescent PHHs since treatment with the entry inhibitor myrcludex-B or nucleoside analogues blocked viral spread and intrahepatic cccDNA accumulation. Viral integrations were detected both in donors and recipient mice but did not appear to contribute to antigen production. CONCLUSIONS We demonstrate that human hepatocyte division even without involvement of cytolytic mechanisms triggers substantial cccDNA loss. This process may be fundamental to resolve self-limiting acute infection and should be considered in future therapeutic interventions along with entry inhibition strategies.
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Affiliation(s)
- Lena Allweiss
- Department of Medicine, Center for Internal Medicine, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Tassilo Volz
- Department of Medicine, Center for Internal Medicine, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Katja Giersch
- Department of Medicine, Center for Internal Medicine, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Janine Kah
- Department of Medicine, Center for Internal Medicine, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Giuseppina Raffa
- Department of Clinical and Experimental Medicine, University Hospital of Messina, Messina, Italy
| | - Joerg Petersen
- IFI Institute for Interdisciplinary Medicine at Asklepios Clinic St. Georg, Hamburg, Germany
| | - Ansgar W Lohse
- Department of Medicine, Center for Internal Medicine, University Medical Center Hamburg-Eppendorf, Hamburg, Germany.,German Center for Infection Research (DZIF), Hamburg-Lübeck-Borstel and Heidelberg Partner Sites, Hamburg, Germany
| | - Concetta Beninati
- Department of Human Pathology, University Hospital of Messina, Messina, Italy
| | - Teresa Pollicino
- Department of Clinical and Experimental Medicine, University Hospital of Messina, Messina, Italy
| | - Stephan Urban
- German Center for Infection Research (DZIF), Hamburg-Lübeck-Borstel and Heidelberg Partner Sites, Hamburg, Germany.,Department of Infectious Diseases, Molecular Virology, University Hospital Heidelberg, Heidelberg, Germany
| | - Marc Lütgehetmann
- Department of Medicine, Center for Internal Medicine, University Medical Center Hamburg-Eppendorf, Hamburg, Germany.,Department of Medical Microbiology, Virology and Hygiene, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Maura Dandri
- Department of Medicine, Center for Internal Medicine, University Medical Center Hamburg-Eppendorf, Hamburg, Germany.,German Center for Infection Research (DZIF), Hamburg-Lübeck-Borstel and Heidelberg Partner Sites, Hamburg, Germany
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22
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Dandri M, Petersen J. Mechanism of Hepatitis B Virus Persistence in Hepatocytes and Its Carcinogenic Potential. Clin Infect Dis 2017; 62 Suppl 4:S281-8. [PMID: 27190317 DOI: 10.1093/cid/ciw023] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
Liver disease associated with persistent infection with hepatitis B virus (HBV) continues to be a major health problem of global impact. Despite the existence of an effective vaccine, at least 240 million people are chronically infected worldwide, and are at risk of developing liver cirrhosis and hepatocellular carcinoma. Although chronic HBV infection is considered the main risk factor for liver cancer development, the molecular mechanisms determining persistence of infection and long-term pathogenesis are not fully elucidated but appear to be multifactorial. Current therapeutic regimens based on the use of polymerase inhibitors can efficiently suppress viral replication but are unable to eradicate the infection. This is due both to the persistence of the HBV genome, which forms a stable minichromosome, the covalently closed circular DNA (cccDNA), in the nucleus of infected hepatocytes, as well as to the inability of the immune system to efficiently counteract chronic HBV infection. In this regard, the unique replication strategies adopted by HBV and viral protein production also appear to contribute to infection persistence by limiting the effectiveness of innate responses. The availability of improved experimental systems and molecular techniques have started to provide new information about the complex network of interactions that HBV establishes within the hepatocyte and that may contribute to disease progression and tumor development. Thus, this review will mostly focus on events involving the hepatocyte: the only target cell where HBV infection and replication take place.
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Affiliation(s)
- Maura Dandri
- I Department of Internal Medicine, University Medical Center Hamburg-Eppendorf German Center for Infection Research, Hamburg-Lübeck-Borstel site
| | - Joerg Petersen
- IFI Institute for Interdisciplinary Medicine, Asklepios Clinic St Georg, Hamburg, Germany
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23
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Abstract
Chronic hepatitis B virus (HBV) infection continues to be a major health burden worldwide; it can cause various degrees of liver damage and is strongly associated with the development of liver cirrhosis and hepatocellular carcinoma. The molecular mechanisms determining HBV persistence are not fully understood, but these appear to be multifactorial and the unique replication strategy employed by HBV enables its maintenance in infected hepatocytes. Both the stability of the HBV genome, which forms a stable minichromosome, the covalently closed circular DNA (cccDNA) in the hepatocyte nucleus, and the inability of the immune system to resolve chronic HBV infection are believed to be key mechanisms of HBV chronicity. Since a true cure of HBV requires clearance of intranuclear cccDNA from infected hepatocytes, understanding the mechanisms involved in cccDNA biogenesis, regulation and stability is mandatory to achieve HBV eradication. This review will summarize the state of knowledge on these mechanisms including the impact of current treatments on the cccDNA stability and activity. We will focus on events challenging cccDNA persistence in dividing hepatocytes.
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Lebossé F, Testoni B, Fresquet J, Facchetti F, Galmozzi E, Fournier M, Hervieu V, Berthillon P, Berby F, Bordes I, Durantel D, Levrero M, Lampertico P, Zoulim F. Intrahepatic innate immune response pathways are downregulated in untreated chronic hepatitis B. J Hepatol 2017; 66:897-909. [PMID: 28043874 DOI: 10.1016/j.jhep.2016.12.024] [Citation(s) in RCA: 102] [Impact Index Per Article: 14.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/05/2016] [Revised: 12/06/2016] [Accepted: 12/20/2016] [Indexed: 12/13/2022]
Abstract
BACKGROUND & AIMS Hepatitis B virus (HBV) persistence and the pathobiology of chronic HBV (CHB) infections result from the interplay between viral replication and host immune responses. We aimed to comprehensively analyse the expression of intrahepatic host genes as well as serum and liver HBV markers in a large cohort of untreated CHB patients. METHODS One-hundred and five CHB patients untreated at the time of liver biopsy (34 HBeAg[+] and 71 HBeAg[-]) were analysed for the intrahepatic expression profile of 67 genes belonging to multiple innate immunity pathways. Results were correlated to serological (quantification of HBsAg [qHBsAg] and HBV DNA) and intrahepatic viral markers (total HBV DNA, pre-genomic RNA and covalently closed circular HBV DNA). RESULTS Intrahepatic gene expression profiling revealed a strong downregulation of antiviral effectors, interferon stimulated genes, Toll-like and pathogen recognition receptor pathways in CHB patients as compared to non-infected controls, which was not directly correlated to HBV replication. A subset of genes [CXCL10, GBP1, IFITM1, IFNB1, IL10, IL6, ISG15, TLR3, SOCS1, SOCS3] was more repressed in HBeAg(-) respect to HBeAg(+) patients (median of serum HBV DNA 7.9×103vs. 7.9×107IU/ml, respectively). Notably, HBeAg(-) patients with lower qHBsAg (<5×103IU/ml) showed a relief of repression of genes belonging to multiple pathways. CONCLUSIONS Our results show a strong impairment of innate immune responses in the liver of CHB patients. The association of low levels of qHBsAg with gene repression, if confirmed, might prove useful for the identification of patients who would most benefit from immune-modulators and/or HBsAg targeting agents as strategies to restore immune responsiveness. LAY SUMMARY Chronic hepatitis B virus (HBV) infections represent a major public health problem worldwide. Over 200 million people are chronically infected and at risk of developing chronic hepatitis, liver cirrhosis and cancer. Our work aimed to understand the molecular consequences of chronic hepatitis B in the infected liver. It was conducted in a large cohort of untreated chronically infected HBV patients and analysed the expression of immunity and liver disease-related genes in the liver, with respect to markers of viral replication and persistence. Our results indicate that chronic HBV infection has a suppressive effect on immune responses, which was more pronounced with high levels of hepatitis B virus surface antigen (HBsAg). These data provide novel insight into the mechanisms of HBV persistence in the liver and suggest that approaches aimed at reducing HBsAg levels, may restore immune responsiveness against the virus.
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Affiliation(s)
- Fanny Lebossé
- INSERM U1052-Cancer Research Center of Lyon (CRCL), 69008 Lyon, France; Department of Hepatology, Croix Rousse Hospital, Hospices Civils de Lyon, France; University of Lyon, UMR_S1052, CRCL, 69008 Lyon, France
| | - Barbara Testoni
- INSERM U1052-Cancer Research Center of Lyon (CRCL), 69008 Lyon, France; University of Lyon, UMR_S1052, CRCL, 69008 Lyon, France
| | - Judith Fresquet
- INSERM U1052-Cancer Research Center of Lyon (CRCL), 69008 Lyon, France; University of Lyon, UMR_S1052, CRCL, 69008 Lyon, France
| | - Floriana Facchetti
- Division of Gastroenterology and Hepatology, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Università degli Studi di Milano, Milan, Italy
| | - Enrico Galmozzi
- Division of Gastroenterology and Hepatology, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Università degli Studi di Milano, Milan, Italy
| | - Maëlenn Fournier
- INSERM U1052-Cancer Research Center of Lyon (CRCL), 69008 Lyon, France; University of Lyon, UMR_S1052, CRCL, 69008 Lyon, France
| | - Valérie Hervieu
- University of Lyon, UMR_S1052, CRCL, 69008 Lyon, France; Department of Pathology, Edouard Heriot Hospital, Hospices Civils de Lyon, France
| | | | - Françoise Berby
- INSERM U1052-Cancer Research Center of Lyon (CRCL), 69008 Lyon, France
| | - Isabelle Bordes
- INSERM U1052-Cancer Research Center of Lyon (CRCL), 69008 Lyon, France
| | - David Durantel
- INSERM U1052-Cancer Research Center of Lyon (CRCL), 69008 Lyon, France; University of Lyon, UMR_S1052, CRCL, 69008 Lyon, France
| | - Massimo Levrero
- INSERM U1052-Cancer Research Center of Lyon (CRCL), 69008 Lyon, France; Department of Hepatology, Croix Rousse Hospital, Hospices Civils de Lyon, France; Department of Internal Medicine - DMISM and the IIT Center for Life Nanoscience (CLNS), Sapienza University, Rome, Italy
| | - Pietro Lampertico
- Division of Gastroenterology and Hepatology, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Università degli Studi di Milano, Milan, Italy
| | - Fabien Zoulim
- INSERM U1052-Cancer Research Center of Lyon (CRCL), 69008 Lyon, France; Department of Hepatology, Croix Rousse Hospital, Hospices Civils de Lyon, France; University of Lyon, UMR_S1052, CRCL, 69008 Lyon, France.
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Kennedy PTF, Litwin S, Dolman GE, Bertoletti A, Mason WS. Immune Tolerant Chronic Hepatitis B: The Unrecognized Risks. Viruses 2017; 9:v9050096. [PMID: 28468285 PMCID: PMC5454409 DOI: 10.3390/v9050096] [Citation(s) in RCA: 51] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2017] [Revised: 04/14/2017] [Accepted: 04/20/2017] [Indexed: 12/13/2022] Open
Abstract
Chronic infection with hepatitis B virus (HBV) progresses through multiple phases, including immune tolerant, immune active, immune control, and, in a subset of patients who achieve immune control, reactivation. The first, the immune tolerant phase, is considered to be prolonged in duration but essentially benign in nature, lacking long-term consequences, and thus not recommended for antiviral therapy. This review challenges the notion that the immune tolerant phase is truly benign and considers the possibility that events during this phase may contribute significantly to cirrhosis, hepatocellular carcinoma (HCC), and the premature death of 25% of HBV carriers worldwide. Thus, earlier treatment than recommended by current guidelines should be considered. Low therapeutic coverage exacerbated by restrictive treatment guidelines may facilitate disease progression in many patients but also increase the risk of neonatal and horizontal transmission from untreated mothers to their children. While a prophylactic vaccine exists, there are many areas worldwide where the treatment of adults and the delivery of an effective vaccination course to newborns present difficult challenges.
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Affiliation(s)
- Patrick T F Kennedy
- Centre for Immunobiology, Blizard Institute, Barts and the London School of Medicine & Dentistry, QMUL, London E1 2AT, UK.
| | - Samuel Litwin
- Fox Chase Cancer Center, Philadelphia, PA 19111, USA.
| | - Grace E Dolman
- Centre for Immunobiology, Blizard Institute, Barts and the London School of Medicine & Dentistry, QMUL, London E1 2AT, UK.
| | - Antonio Bertoletti
- Emerging Infectious Diseases Program, Duke-NUS Graduate Medical School, Singapore.
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26
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Tu T, Budzinska MA, Shackel NA, Urban S. HBV DNA Integration: Molecular Mechanisms and Clinical Implications. Viruses 2017; 9:v9040075. [PMID: 28394272 PMCID: PMC5408681 DOI: 10.3390/v9040075] [Citation(s) in RCA: 231] [Impact Index Per Article: 33.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2017] [Revised: 04/03/2017] [Accepted: 04/04/2017] [Indexed: 02/06/2023] Open
Abstract
Chronic infection with the Hepatitis B Virus (HBV) is a major cause of liver-related morbidity and mortality. One peculiar observation in cells infected with HBV (or with closely‑related animal hepadnaviruses) is the presence of viral DNA integration in the host cell genome, despite this form being a replicative dead-end for the virus. The frequent finding of somatic integration of viral DNA suggests an evolutionary benefit for the virus; however, the mechanism of integration, its functions, and the clinical implications remain unknown. Here we review the current body of knowledge of HBV DNA integration, with particular focus on the molecular mechanisms and its clinical implications (including the possible consequences of replication-independent antigen expression and its possible role in hepatocellular carcinoma). HBV DNA integration is likely to influence HBV replication, persistence, and pathogenesis, and so deserves greater attention in future studies.
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Affiliation(s)
- Thomas Tu
- Department of Infectious Diseases, Molecular Virology, Heidelberg University, Im Neuenheimer Feld 345, 69120 Heidelberg, Germany.
| | - Magdalena A Budzinska
- Centenary Institute, The University of Sydney, Sydney, NSW 2050, Australia.
- Sydney Medical School, The University of Sydney, Sydney, NSW 2006, Australia.
| | - Nicholas A Shackel
- Centenary Institute, The University of Sydney, Sydney, NSW 2050, Australia.
- Sydney Medical School, The University of Sydney, Sydney, NSW 2006, Australia.
- Liverpool Hospital, Gastroenterology, Sydney, NSW 2170, Australia.
| | - Stephan Urban
- Department of Infectious Diseases, Molecular Virology, Heidelberg University, Im Neuenheimer Feld 345, 69120 Heidelberg, Germany.
- German Center for Infection Research (DZIF), Heidelberg Partner Site, Im Neuenheimer Feld 345, 69120 Heidelberg, Germany.
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Tu T, Jilbert AR. Detection of Hepatocyte Clones Containing Integrated Hepatitis B Virus DNA Using Inverse Nested PCR. Methods Mol Biol 2017; 1540:97-118. [PMID: 27975311 DOI: 10.1007/978-1-4939-6700-1_9] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Chronic hepatitis B virus (HBV) infection is a major cause of liver cirrhosis and hepatocellular carcinoma (HCC), leading to ~600,000 deaths per year worldwide. Many of the steps that occur during progression from the normal liver to cirrhosis and/or HCC are unknown. Integration of HBV DNA into random sites in the host cell genome occurs as a by-product of the HBV replication cycle and forms a unique junction between virus and cellular DNA. Analyses of integrated HBV DNA have revealed that HCCs are clonal and imply that they develop from the transformation of hepatocytes, the only liver cell known to be infected by HBV. Integrated HBV DNA has also been shown, at least in some tumors, to cause insertional mutagenesis in cancer driver genes, which may facilitate the development of HCC. Studies of HBV DNA integration in the histologically normal liver have provided additional insight into HBV-associated liver disease, suggesting that hepatocytes with a survival or growth advantage undergo high levels of clonal expansion even in the absence of oncogenic transformation. Here we describe inverse nested PCR (invPCR), a highly sensitive method that allows detection, sequencing, and enumeration of virus-cell DNA junctions formed by the integration of HBV DNA. The invPCR protocol is composed of two major steps: inversion of the virus-cell DNA junction and single-molecule nested PCR. The invPCR method is highly specific and inexpensive and can be tailored to DNA extracted from large or small amounts of liver. This procedure also allows detection of genome-wide random integration of any known DNA sequence and is therefore a useful technique for molecular biology, virology, and genetic research.
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Affiliation(s)
- Thomas Tu
- Liver Cell Biology Laboratory, Centenary Institute, Sydney, NSW, 2050, Australia
- Sydney Medical School, University of Sydney, Sydney, NSW, 2050, Australia
- Department of Molecular and Cellular Biology, School of Biological Sciences, University of Adelaide, Adelaide, SA, 5005, Australia
| | - Allison R Jilbert
- Department of Molecular and Cellular Biology, School of Biological Sciences, University of Adelaide, Adelaide, SA, 5005, Australia.
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Graumann F, Churin Y, Tschuschner A, Reifenberg K, Glebe D, Roderfeld M, Roeb E. Genomic Methylation Inhibits Expression of Hepatitis B Virus Envelope Protein in Transgenic Mice: A Non-Infectious Mouse Model to Study Silencing of HBV Surface Antigen Genes. PLoS One 2015; 10:e0146099. [PMID: 26717563 PMCID: PMC4696744 DOI: 10.1371/journal.pone.0146099] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2015] [Accepted: 12/14/2015] [Indexed: 02/07/2023] Open
Abstract
Objective The Hepatitis B virus genome persists in the nucleus of virus infected hepatocytes where it serves as template for viral mRNA synthesis. Epigenetic modifications, including methylation of the CpG islands contribute to the regulation of viral gene expression. The present study investigates the effects of spontaneous age dependent loss of hepatitis B surface protein- (HBs) expression due to HBV-genome specific methylation as well as its proximate positive effects in HBs transgenic mice. Methods Liver and serum of HBs transgenic mice aged 5–33 weeks were analyzed by Western blot, immunohistochemistry, serum analysis, PCR, and qRT-PCR. Results From the third month of age hepatic loss of HBs was observed in 20% of transgenic mice. The size of HBs-free area and the relative number of animals with these effects increased with age and struck about 55% of animals aged 33 weeks. Loss of HBs-expression was strongly correlated with amelioration of serum parameters ALT and AST. In addition lower HBs-expression went on with decreased ER-stress. The loss of surface protein expression started on transcriptional level and appeared to be regulated epigenetically by DNA methylation. The amount of the HBs-expression correlated negatively with methylation of HBV DNA in the mouse genome. Conclusions Our data suggest that methylation of specific CpG sites controls gene expression even in HBs-transgenic mice with truncated HBV genome. More important, the loss of HBs expression and intracellular aggregation ameliorated cell stress and liver integrity. Thus, targeted modulation of HBs expression may offer new therapeutic approaches. Furthermore, HBs-transgenic mice depict a non-infectious mouse model to study one possible mechanism of HBs gene silencing by hypermethylation.
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Affiliation(s)
- Franziska Graumann
- Department of Gastroenterology, Justus Liebig University, Giessen, Germany
| | - Yuri Churin
- Department of Gastroenterology, Justus Liebig University, Giessen, Germany
| | | | - Kurt Reifenberg
- Central Laboratory Animal Facility, Johannes Gutenberg University, Mainz, Germany
| | - Dieter Glebe
- Institute of Medical Virology, National Reference Centre for Hepatitis B and D Viruses, Justus Liebig University, Giessen, Germany
| | - Martin Roderfeld
- Department of Gastroenterology, Justus Liebig University, Giessen, Germany
| | - Elke Roeb
- Department of Gastroenterology, Justus Liebig University, Giessen, Germany
- * E-mail:
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30
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Ruan P, Dai X, Sun Z, Zhou C, Yang F. Significance of the quantitative measurement of the chr16: 51320015 integration site in hepatocytes of patients with chronic hepatitis B. Mol Med Rep 2015; 12:6855-60. [PMID: 26397742 DOI: 10.3892/mmr.2015.4319] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2014] [Accepted: 07/29/2015] [Indexed: 11/06/2022] Open
Abstract
The present study reported the presence of a hepatitis B virus (HBV) major integration site (MIS) chr16: 51320015 and discussed the significance of quantitative measurement of this site. A total of 30 hepatitis B e antigen (HBeAg) positive (+) and 30 HBeAg negative (‑) patients with chronic hepatitis B (CHB) were enrolled in the present study, and the levels of intrahepatic (IH) covalently closed circular DNA (cccDNA), serum HBV DNA and hepatitis B surface antigen (HBsAg) were detected. Conventional reverse transcription‑quantitative polymerase chain reaction (RT‑qPCR) and Sanger sequencing were designed to verify the chr16: 51320015 integration site, and the copy numbers of this site were measured using molecular clone and SYBR Green I RT‑qPCR. This site was found to be present in the hepatocytes of all the enrolled patients, and the average number of copies was 1.46x10‑2 ± 4.94x10‑2 copies/cell (3.48x10‑5‑0.212 copies/cell). No significant difference in the copy numbers of this site were observed between the HBeAg (+) (1.43 ± 9.79x10‑1 copies/cell) and HBeAg (‑) patients (6.58x10‑2 ± 2.47x10‑2 copies/cell; P>0.05), which were positively correlated with the levels of serum HBsAg (P=0.0038), but were not correlated with the levels of IH cccDNA (P=0.7785). In conclusion, the chr16:51320015 integration site may be a novel site, which persists in a several patients with HBV infection, and may accumulate in the hepatocytes due to clonal expansion. The diagnostic and therapeutic values of this site require further investigation.
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Affiliation(s)
- Peng Ruan
- Department of Gastroenterology, Renmin Hospital, Hubei University of Medicine, Shiyan, Hubei 442000, P.R. China
| | - Xiufang Dai
- Department of Gastroenterology, Renmin Hospital, Hubei University of Medicine, Shiyan, Hubei 442000, P.R. China
| | - Zequn Sun
- Department of Gastroenterology, Renmin Hospital, Hubei University of Medicine, Shiyan, Hubei 442000, P.R. China
| | - Chunfang Zhou
- Department of Gastroenterology, Renmin Hospital, Hubei University of Medicine, Shiyan, Hubei 442000, P.R. China
| | - Fan Yang
- Department of Gastroenterology, Renmin Hospital of Wuhan University, Wuhan, Hubei 430060, P.R. China
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Baran B. Nucleos(t)ide analogs in the prevention of hepatitis B virus related hepatocellular carcinoma. World J Hepatol 2015; 7:1742-1754. [PMID: 26167247 PMCID: PMC4491903 DOI: 10.4254/wjh.v7.i13.1742] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/29/2015] [Revised: 05/06/2015] [Accepted: 06/19/2015] [Indexed: 02/06/2023] Open
Abstract
Hepatocellular carcinoma (HCC) is among the most common cancer types and causes of cancer related mortality worldwide. Almost 50% of all HCC cases globally are attributable to chronic hepatitis B virus (HBV) infection. The incidence rates of HCC in untreated Asian subjects with HBV infection was estimated to be 0.2% in inactive carriers, 0.6% for those with chronic hepatitis without cirrhosis, and 3.7% for those with compensated cirrhosis. In Western populations, HCC incidences are reported to be 0.02% in inactive carriers, 0.3% in subjects with chronic hepatitis without cirrhosis, and 2.2% in subjects with compensated cirrhosis. Despite effective antiviral treatment options which are able to transform chronic hepatitis into an inactive carrier state, the risk of HCC cannot be fully ruled out to exclude those patients from surveillance. Newer nucleos(t)ide analogues (NAs) as entecavir and tenofovir are very potent in terms of sustained virological suppression which leads to improved liver histology. However, they do not have any influence on the cccDNA or integrated DNA of HBV in the liver. Nonetheless, viral replication is the only modifiable component among the established risk factors for HBV-related HCC with the current treatment options. In this review, it was aimed to summarize cumulative evidence behind the concept of prevention of HBV related HCC by NAs, and to discuss remaining obstacles to eliminate the risk of HCC.
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Tu T, Budzinska MA, Shackel NA, Jilbert AR. Conceptual models for the initiation of hepatitis B virus-associated hepatocellular carcinoma. Liver Int 2015; 35:1786-800. [PMID: 25640596 DOI: 10.1111/liv.12773] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/04/2014] [Accepted: 12/18/2014] [Indexed: 12/18/2022]
Abstract
Although chronic hepatitis B virus (HBV) infection is a known risk factor for the development of hepatocellular carcinoma (HCC), the steps involved in the progression from normal liver to HCC are poorly understood. In this review, we apply five conceptual models, previously proposed by Vineis et al. to explain carcinogenesis in general, to explore the possible steps involved in the initiation and evolution of HBV-associated HCC. Available data suggest that the most suitable and inclusive model is based on evolution of hepatocyte subpopulations. In this evolutionary model, HCC-associated changes are driven by selection and subsequent clonal expansion of phenotypically altered hepatocyte subpopulations in the microenvironment of the HBV-infected liver. This model can incorporate the wide range of mechanisms proposed to play a role in the initiation of HCC including oncogenic HBV proteins, integration of HBV DNA and chronic inflammation of the liver. The model may assist in the early prevention, detection and treatment of HCC and may guide future studies of the initiation of HBV-associated HCC.
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Affiliation(s)
- Thomas Tu
- Department of Molecular and Cellular Biology, School of Biological Sciences, University of Adelaide, Adelaide, SA, Australia.,Liver Cell Biology, Centenary Institute, Sydney, NSW, Australia.,Sydney Medical School, University of Sydney, Sydney, NSW, Australia
| | - Magdalena A Budzinska
- Liver Cell Biology, Centenary Institute, Sydney, NSW, Australia.,Sydney Medical School, University of Sydney, Sydney, NSW, Australia
| | - Nicholas A Shackel
- Liver Cell Biology, Centenary Institute, Sydney, NSW, Australia.,Sydney Medical School, University of Sydney, Sydney, NSW, Australia.,A.W. Morrow Gastroenterology and Liver Centre, Royal Prince Alfred Hospital, Sydney, NSW, Australia
| | - Allison R Jilbert
- Department of Molecular and Cellular Biology, School of Biological Sciences, University of Adelaide, Adelaide, SA, Australia
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Infection Patterns Induced in Naive Adult Woodchucks by Virions of Woodchuck Hepatitis Virus Collected during either the Acute or Chronic Phase of Infection. J Virol 2015; 89:8749-63. [PMID: 26063428 DOI: 10.1128/jvi.00984-15] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2015] [Accepted: 06/04/2015] [Indexed: 02/08/2023] Open
Abstract
UNLABELLED The infectivity of hepadnavirus virions produced during either acute or chronic stages of infection was compared by testing the ability of the virions of woodchuck hepatitis virus (WHV) to induce productive acute infection in naive adult woodchucks. Serum WHV collected during acute infection was compared to virions harvested from WHV-infected woodchucks during either (i) early chronic infection, when WHV-induced hepatocellular carcinoma (HCC) was not yet developed, or (ii) late chronic infection, when established HCC was terminal. All tested types of WHV inoculum were related, because they were collected from woodchucks that originally were infected with standardized WHV7 inoculum. Despite the individual differences between animals, the kinetics of accumulation of serum relaxed circular DNA of WHV demonstrated that the virions produced during early or late chronic infection are fully capable of inducing productive acute infection with long-lasting high viremia. These findings were further supported by the analysis of such intrahepatic markers of WHV infection as replicative intermediate DNA, covalently closed circular DNA, pregenomic RNA, and the percentage of WHV core antigen-positive hepatocytes measured at several time points over the course of 17.5 weeks after the inoculation. In addition, the observed relationship between the production of antibodies against WHV surface antigens and parameters of WHV infection appears to be complex. Taken together, the generated data suggest that in vivo hepadnavirus virions produced during different phases of chronic infection did not demonstrate any considerable deficiencies in infectivity compared to that of virions generated during the acute phase of infection. IMPORTANCE The generated data suggest that infectivity of virions produced during the early or late stages of chronic hepadnavirus infection is not compromised. Our novel results provided several lines of further evidence supporting the idea that during the state of chronic infection in vivo, the limitations of hepadnavirus cell-to-cell spread/superinfection (observed recently in the woodchuck model) are not due to the diminished infectivity of the virions circulating in the blood and likely are (i) related to the properties of hepatocytes (i.e., their capacity to support hepadnavirus infection/replication) and (ii) influenced by the immune system. The obtained results further extend the understanding of the mechanisms regulating the persistence of hepadnavirus infection. Follow-up studies that will further investigate hepadnavirus cell-to-cell spread as a potential regulator of the chronic state of the infection are warranted.
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Abstract
The hepatitis B virus (HBV) is a widespread human pathogen that causes liver inflammation, cirrhosis, and hepatocellular carcinoma (HCC). Recent sequencing technologies have refined our knowledge of the genomic landscape and pathogenesis of HCC, but the mechanisms by which HBV exerts its oncogenic role remain controversial. In a prevailing view, inflammation, liver damage, and regeneration may foster the accumulation of genetic and epigenetic defects leading to cancer onset. However, a more direct and specific contribution of the virus is supported by clinical and biological observations. Among genetically heterogeneous HCCs, HBV-related tumors display high genomic instability, which may be attributed to the ability of HBV to integrate its DNA into the host cell genome, provoking chromosomal alterations and insertional mutagenesis of cancer genes. The viral transactivator HBx may also participate in transformation by deregulating diverse cellular machineries. A better understanding of the complex mechanisms linking HBV to HCC will improve prevention and treatment strategies.
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Affiliation(s)
- Marie-Annick Buendia
- Pathogenesis and Treatment of Acute Hepatitis and Liver Cancer Unit, INSERM U785, University Paris-Sud, Paul Brousse Hospital, 94800 Villejuif, France
| | - Christine Neuveut
- Hepacivirus and Innate Immunity Unit, URA CNRS 3015, Institut Pasteur, 75015 Paris, France
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Petersen J, Dandri M. Optimal therapy for chronic hepatitis B: hepatitis B virus combination therapy? Liver Int 2015; 35 Suppl 1:114-20. [PMID: 25529096 DOI: 10.1111/liv.12720] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Currently available antiviral treatment for chronic hepatitis B can be divided into two classes of therapeutic agents: pegylated interferon alpha (PEG-IFN) and nucleos(t)ide analogues (NAs). The major advantages of NAs are good tolerance and potent antiviral activity associated with high rates of on-treatment response to therapy. The advantages of PEG-IFN include a finite course of treatment, the absence of drug resistance, and an opportunity to obtain a durable post-treatment response to therapy. The use of these two antiviral agents with different mechanisms of action in combination is theoretically an attractive approach for treatment, either simultaneously, as sequential combination therapy (add-on), or even as an immediate switch from one agent to the other. Different NAs have also been combined in certain clinical situations. At present, several studies have confirmed certain virological advantages to combination therapies, but pivotal prospective studies demonstrating long-term clinical benefit to patients are still missing. Therefore, combination treatment, especially with PEG-IFN plus NAs, is not indicated and was not recommended by the European Association for the Study of the Liver Clinical Practice Guidelines written in 2012, while the guidelines for the use of combination NAs is limited to very few clinical situations.
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Affiliation(s)
- Jorg Petersen
- IFI Institute at the Asklepios Klinik St Georg Hamburg, University of Hamburg, Hamburg, Germany
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36
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Superinfection with woodchuck hepatitis virus strain WHVNY of livers chronically infected with strain WHV7. J Virol 2014; 89:384-405. [PMID: 25320318 DOI: 10.1128/jvi.02361-14] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
UNLABELLED The determinants of the maintenance of chronic hepadnaviral infection are yet to be fully understood. A long-standing unresolved argument in the hepatitis B virus (HBV) research field suggests that during chronic hepadnaviral infection, cell-to-cell spread of hepadnavirus is at least very inefficient (if it occurs at all), virus superinfection is an unlikely event, and chronic hepadnavirus infection can be maintained exclusively via division of infected hepatocytes in the absence of virus spread. Superinfection exclusion was previously shown for duck HBV, but it was not demonstrated for HBV or HBV-related woodchuck hepatitis virus (WHV). Three woodchucks, which were chronically infected with the strain WHV7 and already developed WHV-induced hepatocellular carcinomas (HCCs), were superinfected with another WHV strain, WHVNY. Six weeks after the superinfection, the woodchucks were sacrificed and tissues of the livers and HCCs were examined. The WHVNY superinfection was demonstrated by using WHV strain-specific PCR assays and (i) finding WHVNY relaxed circular DNA in the serum samples collected from all superinfected animals during weeks one through six after the superinfection, (ii) detecting replication-derived WHVNY RNA in the tissue samples of the livers and HCCs collected from three superinfected woodchucks, and (iii) finding WHVNY DNA replication intermediates in tissues harvested after the superinfection. The results are consistent with the occurrence of continuous but inefficient hepadnavirus cell-to-cell spread and superinfection during chronic infection and suggest that the replication space occupied by the superinfecting hepadnavirus in chronically infected livers is limited. The findings are discussed in the context of the mechanism of chronic hepadnavirus infection. IMPORTANCE This study aimed to better understand the determinants of the maintenance of chronic hepadnavirus infection. The generated data suggest that in the livers chronically infected with woodchuck hepatitis virus, (i) hepadnavirus superinfection and cell-to-cell spread likely continue to occur and (ii) the virus spread is apparently inefficient, which is consistent with the interpretation that a limited number of cells in the livers facilitates the spread of hepadnavirus. The limitations of the cell-to-cell virus spread most likely are mediated at the level of the cells and do not reflect the properties of the virus. Our results further advance the understanding of the mechanism of chronic hepadnavirus infection. The significance of the continuous but limited hepadnavirus spread and superinfection for the maintenance of the chronic state of infection should be further evaluated in follow-up studies in order to determine whether blocking the virus spread would facilitate the suppression of chronic hepadnavirus infection.
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Yang HC, Kao JH. Persistence of hepatitis B virus covalently closed circular DNA in hepatocytes: molecular mechanisms and clinical significance. Emerg Microbes Infect 2014; 3:e64. [PMID: 26038757 PMCID: PMC4185362 DOI: 10.1038/emi.2014.64] [Citation(s) in RCA: 92] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2014] [Revised: 07/17/2014] [Accepted: 07/21/2014] [Indexed: 02/06/2023]
Abstract
Covalently closed circular DNA (cccDNA) is the transcriptional template of hepatitis B virus (HBV). Extensive research over the past decades has unveiled the important role of cccDNA in the natural history and antiviral treatment of chronic HBV infection. cccDNA can persist in patients recovering from acute HBV infection for decades. This explains why HBV reactivation occasionally occurs in patients with resolved hepatitis B receiving intensive immunosuppressive agents. In addition, although advances in antiviral treatment dramatically improve the adverse outcomes of chronic hepatitis B (CHB), accumulating evidence demonstrates that current antiviral treatments alone, be they nucleos(t)ide analogs (NAs) or interferon (IFN), fail to cure most CHB patients because of the persistent cccDNA. NA suppresses HBV replication by directly inhibiting viral polymerase, while IFN enhances host immunity against HBV infection. Viral rebound often occurs after discontinuation of antiviral treatment. The loss of cccDNA can be induced by non-cytolytic destruction of cccDNA or immune-mediated killing of infected hepatocytes. It is known that NA has no direct effect on viral transcription or cccDNA stability. Therefore, the long half-life of hepatocytes leads to a very slow decline in cccDNA in patients under antiviral therapy. Novel antiviral agents targeting cccDNA or cccDNA-containing hepatocytes are thus required for curing chronic HBV infection.
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Affiliation(s)
- Hung-Chih Yang
- Department of Microbiology, National Taiwan University College of Medicine , Taipei 10002, Taiwan, China ; Graduate Institute of Clinical Medicine, National Taiwan University College of Medicine , Taipei 10002, Taiwan, China ; Department of Internal Medicine, National Taiwan University Hospital , Taipei 10002, Taiwan, China
| | - Jia-Horng Kao
- Graduate Institute of Clinical Medicine, National Taiwan University College of Medicine , Taipei 10002, Taiwan, China ; Department of Internal Medicine, National Taiwan University Hospital , Taipei 10002, Taiwan, China ; Hepatitis Research Center, National Taiwan University Hospital , Taipei 10002, Taiwan, China ; Department of Medical Research, National Taiwan University Hospital , Taipei 10002, Taiwan, China
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Gill US, Kennedy PTF. Chronic hepatitis B virus in young adults: the need for new approaches to management. Expert Rev Anti Infect Ther 2014; 12:1045-53. [PMID: 25052517 DOI: 10.1586/14787210.2014.940899] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
One in four patients infected with hepatitis B virus (HBV) at birth or in early childhood will develop cirrhosis or hepatocellular carcinoma. Historically, guidelines have overlooked treatment in young people, as the immune tolerant disease phase is considered synonymous with chronic infection in the young. Current treatment aims to suppress HBV replication through long-term nucleos(t)ide therapy with little emphasis on virus eradication. To achieve HBsAg loss, it is accepted that effective immune control of virus is required, mimicking that seen in those who resolve acute HBV infection. We have recently challenged the accuracy of a generic immune tolerant state in young people, thus raising a potential role for earlier treatment. Here we report on our immunological analysis of HBV in young people and the role of a dedicated clinic; we make the case for earlier intervention to achieve effective immune control leading to better outcomes.
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Affiliation(s)
- Upkar S Gill
- Hepatology Unit, Centre for Digestive Diseases, Blizard Institute, Barts and The London School of Medicine and Dentistry, Queen Mary University of London, London, UK
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Dandri M, Lütgehetmann M. Mouse models of hepatitis B and delta virus infection. J Immunol Methods 2014; 410:39-49. [PMID: 24631647 DOI: 10.1016/j.jim.2014.03.002] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2014] [Revised: 03/03/2014] [Accepted: 03/04/2014] [Indexed: 01/05/2023]
Abstract
Liver disease associated to persistent infection with the hepatitis B virus (HBV) continues to be a major health problem of global impact. Therapeutic regimens currently available can efficiently suppress HBV replication; however, the unique replication strategies employed by HBV permit the virus to persist within the infected hepatocytes. As a consequence, relapse of viral activity is commonly observed after cessation of treatment with polymerase inhibitors. Among the HBV chronically infected patients, more than 15million patients are estimated to be co-infected with the hepatitis delta virus (HDV), a defective satellite virus that needs the HBV envelope for propagation. No specific drugs are currently available against HDV, while nucleos(t)ide analogs are not effective against HDV replication. Since chronic HBV/HDV co-infection leads to the most severe form of chronic viral hepatitis in men, a better understanding of the molecular mechanisms of HDV-mediated pathogenesis and the development of improved therapeutic approaches is urgently needed. The obvious limitations imposed by the use of great apes and the paucity of robust experimental models of HBV infection have hindered progresses in understanding the complex network of virus-host interactions that are established in the course of HBV and HDV infections. This review focuses on summarizing recent advances obtained with well-established and more innovative experimental mouse models, giving emphasis on the strength of infection systems based on the reconstitution of the murine liver with human hepatocytes, as tools for elucidating the whole life cycle of HBV and HDV, as well as for studies on interactions with the infected human hepatocytes and for preclinical drug evaluation.
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Affiliation(s)
- Maura Dandri
- I. Department of Internal Medicine, University Medical Center Hamburg-Eppendorf, Hamburg, Germany; German Center for Infection Research, Hamburg-Lübeck-Borstel Partner Site, Germany.
| | - Marc Lütgehetmann
- I. Department of Internal Medicine, University Medical Center Hamburg-Eppendorf, Hamburg, Germany; Institute of Microbiology, Virology and Hygiene, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
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Impact of occult hepatitis B virus infection or hepatitis B virus DNA integration on efficacy of chronic hepatitis C treatment with peginterferon and ribavirin: where are we? J Clin Gastroenterol 2014; 48:3-5. [PMID: 24045272 DOI: 10.1097/mcg.0b013e3182a6633d] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/10/2022]
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41
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Warner N, Locarnini S. The new front-line in hepatitis B/D research: identification and blocking of a functional receptor. Hepatology 2013; 58:9-12. [PMID: 23390015 DOI: 10.1002/hep.26292] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 01/08/2013] [Indexed: 12/31/2022]
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42
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Liu B, Wen X, Huang C, Wei Y. Unraveling the complexity of hepatitis B virus: from molecular understanding to therapeutic strategy in 50 years. Int J Biochem Cell Biol 2013; 45:1987-96. [PMID: 23819994 DOI: 10.1016/j.biocel.2013.06.017] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2013] [Revised: 06/18/2013] [Accepted: 06/21/2013] [Indexed: 02/05/2023]
Abstract
Hepatitis B virus (HBV) is a well-known hepadnavirus with a double-stranded circular DNA genome. Although HBV was first described approximately 50 years ago, the precise mechanisms of HBV infection and effective therapeutic strategies remain unclear. Here, we focus on summarizing the complicated mechanisms of HBV replication and infection, as well as genomic factors and epigenetic regulation. Additionally, we discuss in vivo models of HBV, as well as diagnosis, prevention and therapeutic drugs for HBV. Together, the data in this 50-year review may provide new clues to elucidate molecular mechanisms of HBV pathogenesis and shed new light on the future HBV therapies.
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Affiliation(s)
- Bo Liu
- State Key Laboratory of Biotherapy, West China Hospital, Sichuan University, Chengdu 610041, China
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Mukherjee RM, Shravanti GV, Jakkampudi A, Kota R, Jangala AL, Reddy PB, Rao PN, Gupta R, Reddy DN. Reduced Expression of DNA Damage Repair Genes High Mobility Group Box1 and Poly(ADP-ribose) Polymerase1 in Inactive Carriers of Hepatitis B Virus Infection-A Possible Stage of Viral Integration. J Clin Exp Hepatol 2013; 3:89-95. [PMID: 25755481 PMCID: PMC3940113 DOI: 10.1016/j.jceh.2013.04.003] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/13/2013] [Accepted: 04/25/2013] [Indexed: 12/12/2022] Open
Abstract
BACKGROUND High mobility group box1 (HMGB1) and poly(ADP-ribose) polymerase1 (PARP1) proteins repair cellular DNA damage. Reduced expression of the corresponding genes can lead to an impaired DNA damage repair mechanism. Intracellular replication of hepatitis B virus (HBV) in such conditions can favor the integration of viral DNA into host genome leading to the development of hepatocellular carcinoma (HCC). OBJECTIVE This study was performed to assess the expression of HMGB1 and PARP1 mRNAs in conjunction with the estimation of HBV replication intermediate pregenomic RNA (PgRNA) in various phases of HBV infection. MATERIALS Eighty eight patients and 26 voluntary blood donors as controls were included in the study. Patients were grouped in to acute (AHB; n = 15), inactive carriers (IC; n = 36), cirrhosis (Cirr; n = 25) and hepatocellular carcinoma (HCC; n = 12). Serum HBV DNA was quantified by real time polymerase chain reaction (PCR) assay. Expression of HMGB1, PARP1 and PgRNA were evaluated using peripheral blood mononuclear cells (PBMCs) derived RNA by reverse transcription PCR (RT-PCR) and densitometry. RESULTS Significant reduction of HMGB1 and PARP1 gene expressions (P < 0.05) were observed in patients than controls with more explicit decline of PARP1 (P = 0.0002). Both genes were significantly downregulated (P < 0.001) in ICs than controls. In ICs, HMGB1 was significantly lowered than cirrhosis (P = 0.002) and HCC (P = 0.0006) while PARP1 declined significantly (P = 0.04) than HCC. Level of PgRNA was comparable in all the disease categories. CONCLUSION In conclusion, our findings indicate impaired DNA damage repair mechanisms in HBV infected cells of ICs. This, along with low viral load but higher level of PgRNA in this group is suggestive of the diversion of HBV replication pathway that might facilitate viral DNA integration in to host genome. Intrusion of HBV PgRNA reverse transcription in early stage of infection might appear advantageous to thwart the development of HCC.
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Key Words
- ADP, adenosine diphosphate
- AHB, acute hepatitis B
- ALT, alanine transferase
- AST, aspartate transferase
- BER, base excision repair
- CHB, chronic HBV
- CIRRH, cirrhosis
- CP, Child–Pugh
- DEPC, diethyl pyrocarbonate
- DTT, dithiothreitol
- ELISA, enzyme-linked immunosorbent assay
- HAV, hepatitis A virus
- HBV, hepatitis B virus
- HBX, hepatitis B virus X protein
- HBeAg, hepatitis B virus e antigen
- HBsAg, hepatitis B virus surface antigen
- HCC, hepatocellular carcinoma
- HDV, hepatitis delta virus
- HEV, hepatitis E virus
- HIV, human immunodeficiency virus
- HMGB1, high mobility group box1
- IC, inactive carriers
- IgG, immunoglobulin G
- IgM, immunoglobulin M
- MuLV-H, moloney murine leukemia virus Rnase H
- NER, nucleotide excision repair
- PARP1, poly(ADP-ribose) polymerase1
- PBMCs, peripheral blood mononuclear cells
- PCR, polymerase chain reaction
- PgRNA, pregenomic RNA
- RT-PCR, reverse transcription PCR
- SD, standard deviation
- UISs, unique integration sites
- cccDNA, covalently closed circular DNA
- dNTPs, deoxynucleoside triphosphates
- dsDNA, double stranded HBV DNA
- gene expression
- hepatitis B virus
- high mobility group box1
- poly(ADP-ribose) polymerase1
- pregenomic RNA
- rcDNA, relaxed circular DNA
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Affiliation(s)
- Rathindra M. Mukherjee
- Asian Health Care Foundation, Institute of Basic and Translational Research, 6-3-661, Somajiguda, Hyderabad 500082, India
- Address for correspondence: Dr. R.M. Mukherjee, Institute of Basic and Translational Research, Asian Health Care Foundation, 6-3-661, Somajiguda, Hyderabad 500082, India. Tel.: +91 40 23378888x742; fax: +91 40 23324255.
| | | | - Aparna Jakkampudi
- Asian Health Care Foundation, Institute of Basic and Translational Research, 6-3-661, Somajiguda, Hyderabad 500082, India
| | - Ramya Kota
- Asian Health Care Foundation, Institute of Basic and Translational Research, 6-3-661, Somajiguda, Hyderabad 500082, India
| | - Asha L. Jangala
- Asian Health Care Foundation, Institute of Basic and Translational Research, 6-3-661, Somajiguda, Hyderabad 500082, India
| | - Panyala B. Reddy
- Asian Health Care Foundation, Institute of Basic and Translational Research, 6-3-661, Somajiguda, Hyderabad 500082, India
| | - Padaki N. Rao
- Asian Institute of Gastroenterology, Somajiguda, Hyderabad, India
| | - Rajesh Gupta
- Asian Institute of Gastroenterology, Somajiguda, Hyderabad, India
| | - Duvvuru N. Reddy
- Asian Institute of Gastroenterology, Somajiguda, Hyderabad, India
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Koissi N, Fishbein JC. Trapping of a cross-link formed by a major purine adduct of a metabolite of the carcinogen N-nitrosomorpholine by inorganic and biological reductants. Chem Res Toxicol 2013; 26:732-40. [PMID: 23587048 DOI: 10.1021/tx3005289] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
3-Hydroperoxy-N-nitrosomorpholine in buffered aqueous media in the presence of calf thymus DNA was treated with a phosphine reductant to generate the transient α-hydroxynitrosamine and subsequent diazonium ion that alkylated the DNA, as previously reported. Subsequent addition of hydride donors, for 30 min, followed by acid hydrolysis of the mixture allowed detection and quantification of 6-(2-{2-[(9H-purin-6-yl)amino]ethoxy}ethoxy)-9H-purin-2-amine, the reduced cross-link formed from deposition, via the diazonium ion, of a 3-oxapentanal fragment on O(6)-Gua, and condensation with N(6)-Ade, presumably in the vicinity. Decreasing the temperature of the reaction mixtures and decreasing the pH modestly increased the yields of the trapped cross-link. Among three borohydride reductants, NaNCBH3 is superior, being ∼4 times more effective on a molar basis, as opposed to a hydride equivalent basis, than NaBH4 or Na(AcO)3BH. For trapping with NaNCBH3, it is deduced that the reaction likely occurs with the iminium ion that is in protonic equilibrium with its conjugate base imine. In an experiment in which the hydroperoxide was decomposed and NaNCBH3 was introduced after various periods of time, the amount of cross-link was observed to increase, nearly linearly, by ∼4-fold over 1 week. These data indicate that there are a minimum of two populations of cross-links, one that forms rapidly, in minutes, and another that grows in with time, over days. Reduced nicotinamide cofactors and ascorbate are observed to effect reduction (over 3 days) of the cross-links, confirming the possibility that otherwise reversible cross-links might be immortalized under biological conditions.
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Affiliation(s)
- Niangoran Koissi
- Department of Chemistry and Biochemistry, University of Maryland, Baltimore County , Baltimore, Maryland 21250, United States
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45
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Block TM, Gish R, Guo H, Mehta A, Cuconati A, Thomas London W, Guo JT. Chronic hepatitis B: what should be the goal for new therapies? Antiviral Res 2013; 98:27-34. [PMID: 23391846 DOI: 10.1016/j.antiviral.2013.01.006] [Citation(s) in RCA: 99] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2012] [Revised: 01/14/2013] [Accepted: 01/28/2013] [Indexed: 02/07/2023]
Abstract
Chronic hepatitis B can currently be medically managed with either pegylated interferon-alpha (pegIFN-α) or one of the five nucleos(t)ide analog Direct Acting Antivirals (DAAs) that inhibit the hepatitis B virus (HBV) DNA polymerase. While pegIFN-α is effective in approximately one-third of the treated patients, the polymerase inhibitors significantly reduce viral load in the vast majority of those treated. However, neither pegIFN-α nor nucleosi(t)de analogs are capable of reliably eliminating the virus and achieving a cure. Moreover, the interferons and polymerase inhibitors are recommended by US, European and Asian professional society practice guidelines for use in only a subset of those infected with HBV. This subset is the population with the greatest levels of circulating viral DNA and abnormal liver function. Although this is the population at the highest risk for cirrhosis and liver cancer, those who fall outside the treatment guidelines, with low levels of viral replication and normal serum ALTs, may also benefit from antiviral therapy. The questions are thus: are new classes of drugs needed to manage chronic hepatitis B? Is a cure possible? Is a cure even necessary? It is therefore important to define the meaning of a cure and determine what the goals of new therapies should be. In this article, we address those questions and propose two operational definitions of medically attainable cures. The first is a "functional cure" based on the clinical outcome, in which the patient's life expectancy becomes the same as that of an individual who has resolved his HBV infection without therapy. Because such an outcome cannot be measured over the short term, we also define an "apparent virological cure," based on the stable off-drug suppression of HBV viremia and antigenemia and the normalization of ALTs and other laboratory tests. We suggest that such a virological cure should be the goal of future therapeutics in all patients with chronic hepatitis B. The extent to which a virological cure predicts a functional cure will only be determined by long-term follow-up.
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Affiliation(s)
- Timothy M Block
- Department of Microbiology and Immunology, Drexel University College of Medicine, 3805 Old Easton Road, Doylestown, PA 18902, USA.
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Dandri M, Lütgehetmann M, Petersen J. Experimental models and therapeutic approaches for HBV. Semin Immunopathol 2012; 35:7-21. [PMID: 22898798 DOI: 10.1007/s00281-012-0335-7] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2012] [Accepted: 07/31/2012] [Indexed: 12/12/2022]
Abstract
Liver disease associated to persistent infection with the hepatitis B virus (HBV) continues to be a major health problem of global impact. In spite of the existence of an effective vaccine, approximately 360 million people are chronically infected worldwide, who are at high risk of developing liver cirrhosis and hepatocellular carcinoma. Although current therapeutic regimens can efficiently suppress viral replication, the unique replication strategies employed by HBV permit the virus to persist within the infected hepatocytes. As a consequence, relapse of viral activity is commonly observed after cessation of treatment with polymerase inhibitors. The narrow host range of HBV has hindered progresses in understanding specific steps of HBV replication and the development of more effective therapeutic strategies aiming at achieving sustained viral control and, eventually, virus eradication. This review will focus on summarizing recent advances obtained with well-established and more innovative experimental models, giving emphasis on the strength of the different systems as tools for elucidating distinct aspects of HBV persistence and for the development of new therapeutic approaches.
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Affiliation(s)
- Maura Dandri
- Department of Internal Medicine, University Medical Center Hamburg-Eppendorf, Hamburg, Germany.
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47
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Mathematical models of e-antigen mediated immune tolerance and activation following prenatal HBV infection. PLoS One 2012; 7:e39591. [PMID: 22768303 PMCID: PMC3388102 DOI: 10.1371/journal.pone.0039591] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2012] [Accepted: 05/24/2012] [Indexed: 02/07/2023] Open
Abstract
We develop mathematical models for the role of hepatitis B e-antigen in creating immunological tolerance during hepatitis B virus infection and propose mechanisms for hepatitis B e-antigen clearance, subsequent emergence of a potent cellular immune response, and the effect of these on liver damage. We investigate the dynamics of virus-immune cells interactions, and derive parameter regimes that allow for viral persistence. We modify the model to account for mechanisms responsible for hepatitis B e-antigen loss, such as seroconversion and virus mutations that lead to emergence of cellular immune response to the mutant virus. Our models demonstrate that either seroconversion or mutations can induce immune activation and that instantaneous loss of e-antigen by either mechanism is associated with least liver damage and is therefore more beneficial for disease outcomes.
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Wang BJ, Tian YJ, Meng ZJ, Jiang M, Wei BQ, Tao YQ, Fan W, Li AY, Bao JJ, Li XY, Zhang ZM, Wang ZD, Wang H, Roggendorf M, Lu MJ, Yang DL. Establishing a new animal model for hepadnaviral infection: susceptibility of Chinese Marmota-species to woodchuck hepatitis virus infection. J Gen Virol 2010; 92:681-91. [PMID: 21084496 DOI: 10.1099/vir.0.025023-0] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
Hepatitis B virus infection (HBV) is a major medical problem in China. The lack of a suitable infection model in China is recognized as an obstacle for research on HBV in China. Chinese Marmota-species is phylogenetically closely related to Marmota monax, thus, it might be suitable to serve as an animal model for HBV infection. Therefore, we attempted to prove the claim about the existence of woodchuck hepatitis virus (WHV)-like viruses in Chinese Marmota-species and to determine the susceptibility of these species to experimental WHV infection. In the present study, 653 sera from three Chinese Marmota-species, Marmota himalayana, Marmota baibacina and Marmota bobak, were screened for WHV-like viruses by serological and molecular assays. The susceptibility to WHV of three species was investigated by experimental infection and monitored by testing of anti-WHc and WHsAg by ELISA, detection of WHV DNA by PCR, and detection of WHV replication intermediates and antigens in liver samples. No evidence for the existence of a genetically closely related virus to WHV in three Chinese Marmota-species was found by serological assays and PCR. M. himalayana was susceptible to WHV infection as inoculated animals became positive for anti-WHc, WHsAg and WHV DNA. Further, WHV replication intermediates and proteins were detected in liver samples. In contrast, M. baibacina remained negative for tested virological parameters. M. bobak species showed a limited susceptibility to WHV. Our data do not support early reports about WHV-like viruses in China. M. himalayana is suitable for the establishment of a model for hepadnaviral infection.
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Affiliation(s)
- Bao-Ju Wang
- Division of Clinical Immunology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, PR China
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Abstract
The introduction of nucleos(t)ide analog therapy has seen the emergence of antiviral drug resistance, which has become the main factor limiting the long-term application of these antiviral agents for patients with chronic hepatitis B. The prevention of resistance requires the adoption of strategies that effectively control virus replication and exploit an understanding of the mechanisms and processes that drive the emergence of drug resistance, namely high replication rates, low fidelity of the hepatitis B virus rt/polymerase, selective pressure of the nucleos(t)ide analog, role of replication space (liver turnover), fitness of the mutant, and genetic barrier to the drug.
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50
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Lutgehetmann M, Volz T, Köpke A, Broja T, Tigges E, Lohse AW, Fuchs E, Murray JM, Petersen J, Dandri M. In vivo proliferation of hepadnavirus-infected hepatocytes induces loss of covalently closed circular DNA in mice. Hepatology 2010; 52:16-24. [PMID: 20578126 DOI: 10.1002/hep.23611] [Citation(s) in RCA: 67] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
UNLABELLED Chronic hepatitis B virus (HBV) infection is maintained by the presence of covalently closed circular DNA (cccDNA), the template of viral transcription and replication. In quiescent hepatocytes, cccDNA is a stable molecule that can persist throughout the hepatocyte lifespan. However, in chronic HBV infection, immunomediated cell injury and compensatory hepatocyte proliferation may favor cccDNA decline and selection of cccDNA-free cells. To investigate the impact of liver regeneration on cccDNA stability and activity in vivo, we used the urokinase-type plasminogen activator (uPA)/severe combined immunodeficiency (SCID) mouse model. Primary tupaia hepatocytes (PTHs) chronically infected with woolly monkey HBV (WM-HBV) were isolated from one highly viremic uPA/SCID chimeric mouse and transplanted into 20 uPA recipients. Expansion of transplanted PTHs and viral load changes were determined by real-time polymerase chain reaction and immunohistochemistry. Transplantation of WM-HBV infected hepatocytes led to an average of 3.8 PTH doublings within 80 days, 75% reduction of virion productivity (relaxed circular DNA/cccDNA), and lower expression levels of pregenomic RNA and hepatitis B core antigen. Remarkably, a median 2-log decline of cccDNA per cell determined during PTH proliferation was due to both dilution of the cccDNA pool among daughter cells and a 0.5-log loss of intrahepatic cccDNA loads (P = 0.02). Intrahepatic viral DNA sequences persisting at the end of the study were mostly present as replicative intermediates and not as integrated virus. CONCLUSION Cell division in the setting of liver regeneration and without administration of antiviral drugs induced strong destabilization of the cccDNA reservoir, resulting in cccDNA clearance in the great majority of chronically infected hepatocytes.
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Affiliation(s)
- Marc Lutgehetmann
- Department of Medicine, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
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