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Saravanan S, Shankar EM, Vignesh R, Ganesh PS, Sankar S, Velu V, Smith DM, Balakrishnan P, Viswanathan D, Govindasamy R, Venkateswaran AR. Occult hepatitis B virus infection and current perspectives on global WHO 2030 eradication. J Viral Hepat 2024; 31:423-431. [PMID: 38578122 DOI: 10.1111/jvh.13928] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/20/2023] [Revised: 01/13/2024] [Accepted: 01/28/2024] [Indexed: 04/06/2024]
Abstract
The current World Health Organization (WHO) Hepatitis Elimination Strategy suffers from lack of a target for diagnosing or expunging occult HBV infection. A sizable segment of the global population has an undetected HBV infection, particularly the high-risk populations and those residing in countries like India with intermediate endemicity. There is growing proof that people with hidden HBV infection can infect others, and that these infections are linked to serious chronic hepatic complications, especially hepatocellular carcinoma. Given the current diagnostic infrastructure in low-resource settings, the WHO 2030 objective of obliterating hepatitis B appears to be undeniably challenging to accomplish. Given the molecular basis of occult HBV infection strongly linked to intrahepatic persistence, patients may inexplicably harbour HBV genomes for a prolonged duration without displaying any pronounced clinical or biochemical signs of liver disease, and present histological signs of moderate degree necro-inflammation, diffuse fibrosis, and hence the international strategy to eradicate viral hepatitis warrants inclusion of occult HBV infection.
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Affiliation(s)
- Shanmugam Saravanan
- Centre for Infectious Diseases, Saveetha Medical College and Hospital, Saveetha Institute of Medical and Technical Sciences (SIMATS), Saveetha University, Chennai, Tamil Nadu, India
| | - Esaki M Shankar
- Infection and Inflammation, Department of Biotechnology, Central University of Tamil Nadu, Thiruvarur, Tamil Nadu, India
| | - Ramachandran Vignesh
- Pre-Clinical Department, Faculty of Medicine, Royal College of Medicine Perak, Universiti Kuala Lumpur, Ipoh, Malaysia
| | - Pitchaipillai Sankar Ganesh
- Department of Microbiology, Saveetha Dental College and Hospitals, Saveetha Institute of Medical and Technical Sciences (SIMATS), Saveetha University, Chennai, Tamil Nadu, India
| | - Sathish Sankar
- Department of Microbiology, Saveetha Dental College and Hospitals, Saveetha Institute of Medical and Technical Sciences (SIMATS), Saveetha University, Chennai, Tamil Nadu, India
| | - Vijayakumar Velu
- Division of Microbiology and Immunology, Emory Vaccine Center, Emory University, Atlanta, Georgia, USA
| | - Davey M Smith
- Department of Medicine, University of California San Diego, La Jolla, California, USA
| | - Pachamuthu Balakrishnan
- Centre for Infectious Diseases, Saveetha Medical College and Hospital, Saveetha Institute of Medical and Technical Sciences (SIMATS), Saveetha University, Chennai, Tamil Nadu, India
| | - Dhivya Viswanathan
- Centre for Nanobioscience, Department of Orthodontics, Saveetha Dental College and Hospitals, Saveetha Institute of Medical and Technical Sciences (SIMATS), Saveetha University, Chennai, Tamil Nadu, India
| | - Rajakumar Govindasamy
- Centre for Nanobioscience, Department of Orthodontics, Saveetha Dental College and Hospitals, Saveetha Institute of Medical and Technical Sciences (SIMATS), Saveetha University, Chennai, Tamil Nadu, India
| | - Arcot R Venkateswaran
- Department of Medical Gastroenterology and Hepatology, Saveetha Medical College and Hospitals (SMCH), Saveetha Institute of Medical and Technical Sciences (SIMATS), Chennai, Tamil Nadu, India
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Anderson M, Phinius BB, Phakedi BK, Mudanga M, Bhebhe LN, Tlhabano GN, Motshosi P, Ratsoma T, Baruti K, Mpebe G, Choga WT, Marlink R, Glebe D, Blackard JT, Moyo S, Kramvis A, Gaseitsiwe S. Persistence and risk factors of occult hepatitis B virus infections among antiretroviral therapy-naïve people living with HIV in Botswana. Front Microbiol 2024; 15:1342862. [PMID: 38784816 PMCID: PMC11112038 DOI: 10.3389/fmicb.2024.1342862] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2023] [Accepted: 04/22/2024] [Indexed: 05/25/2024] Open
Abstract
Aim This study aimed to determine the kinetics of occult hepatitis B virus infections (OBI) among people with HIV (PWH). Methods The study used archived plasma samples from longitudinal HIV natural history studies. We identified new OBI cases and assessed risk factors for OBI using Cox proportional hazards regression analysis. Results At baseline, 8 of 382 [(2.1%) (95% CI: 1.06-4.1)] samples tested positive for hepatitis B surface antigen (HBsAg+). Of the 374 HBsAg-negative samples, 76 had sufficient sample volume for HBV DNA screening. OBI positivity (OBI+) at baseline was reported in 11 of 76 [14.7 95% CI (8.3-24.1)] HBsAg-negative (HBsAg-) participants. Baseline HBsAg-negative samples with sufficient follow-up samples (n = 90) were used for analysis of newly identified OBI cases. Participants contributed 129.74 person-years to the study and were followed for a median of 1.02 years (IQR: 1.00-2.00). Cumulatively, there were 34 newly identified OBI cases from the 90 participants, at the rate of 26.2/100 person-years (95% CI: 18.7-36.7). Newly identified OBI cases were more common among men than women (61.1% vs. 31.9%) and among participants with CD4+ T-cell counts ≤450 cells/mL (p-value = 0.02). Most of the newly identified OBI cases [55.9% (19/34)] were possible reactivations as they were previously HBV core antibody positive. Conclusion There was a high rate of newly identified OBI among young PWH in Botswana, especially in men and in participants with lower CD4+ T-cell counts. OBI screening in PWH should be considered because of the risk of transmission, possible reactivation, and risk factors for the development of chronic liver disease, including hepatocellular carcinoma.
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Affiliation(s)
- Motswedi Anderson
- Research Laboratory, Botswana Harvard Health Partnership, Gaborone, Botswana
| | - Bonolo B. Phinius
- Research Laboratory, Botswana Harvard Health Partnership, Gaborone, Botswana
- School of Allied Health Professions, Faculty of Health Sciences, University of Botswana, Gaborone, Botswana
| | | | - Mbatshi Mudanga
- Botswana – University of Maryland School of Medicine Health Initiative, Gaborone, Botswana
| | - Lynnette N. Bhebhe
- Research Laboratory, Botswana Harvard Health Partnership, Gaborone, Botswana
| | - Girlie N. Tlhabano
- Research Laboratory, Botswana Harvard Health Partnership, Gaborone, Botswana
| | - Patience Motshosi
- Research Laboratory, Botswana Harvard Health Partnership, Gaborone, Botswana
| | - Tsholofelo Ratsoma
- Research Laboratory, Botswana Harvard Health Partnership, Gaborone, Botswana
| | - Kabo Baruti
- Research Laboratory, Botswana Harvard Health Partnership, Gaborone, Botswana
- Department of Biological Sciences, Faculty of Science, University of Botswana, Gaborone, Botswana
| | - Gorata Mpebe
- Research Laboratory, Botswana Harvard Health Partnership, Gaborone, Botswana
| | - Wonderful T. Choga
- Research Laboratory, Botswana Harvard Health Partnership, Gaborone, Botswana
- School of Allied Health Professions, Faculty of Health Sciences, University of Botswana, Gaborone, Botswana
| | - Richard Marlink
- Research Laboratory, Botswana Harvard Health Partnership, Gaborone, Botswana
- Rutgers Global Health Institute, Rutgers University, New Brunswick, NJ, United States
| | - Dieter Glebe
- Institute of Medical Virology, National Reference Centre for Hepatitis B Viruses and Hepatitis D Viruses, Justus Liebig University of Giessen, Giessen, Germany
| | - Jason T. Blackard
- Division of Digestive Diseases, University of Cincinnati College of Medicine, Cincinnati, OH, United States
| | - Sikhulile Moyo
- Research Laboratory, Botswana Harvard Health Partnership, Gaborone, Botswana
- School of Allied Health Professions, Faculty of Health Sciences, University of Botswana, Gaborone, Botswana
- Department of Immunology and Infectious Diseases, Harvard T.H. Chan School of Public Health, Boston, MA, United States
- Division of Medical Virology, Faculty of Medicine and Health Sciences, University of Stellenbosch, Cape Town, South Africa
- School of Health Systems and Public Health, University of Pretoria, Pretoria, South Africa
| | - Anna Kramvis
- Hepatitis Virus Diversity Research Unit, Department of Internal Medicine, School of Clinical Medicine, University of the Witwatersrand, Johannesburg, South Africa
| | - Simani Gaseitsiwe
- Research Laboratory, Botswana Harvard Health Partnership, Gaborone, Botswana
- Department of Immunology and Infectious Diseases, Harvard T.H. Chan School of Public Health, Boston, MA, United States
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He P, Zhang P, Fang Y, Han N, Yang W, Xia Z, Zhu Y, Zhang Z, Shen J. The role of HBV cccDNA in occult hepatitis B virus infection. Mol Cell Biochem 2023; 478:2297-2307. [PMID: 36735210 DOI: 10.1007/s11010-023-04660-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2022] [Accepted: 01/09/2023] [Indexed: 02/04/2023]
Abstract
Occult hepatitis B virus (HBV) infection (OBI) refers to the presence of replication-competent HBV DNA in the liver, with or without HBV DNA in the blood, in individuals who tested negative for HBV surface antigen (HBsAg). In this peculiar phase of HBV infection, the covalently closed circular DNA (cccDNA) is in a low state of replication. Several advances have been made toward clarifying the mechanisms involved in such a suppression of viral activity, which seems to be mainly related to the host's immune control and epigenetic factors. Although the underlying mechanisms describing the genesis of OBI are not completely known, the presence of viral cccDNA, which remains in a low state of replication due to the host's strong immune suppression of HBV replication and gene expression, appears to be the causative factor. Through this review, we have provided an updated account on the role of HBV cccDNA in regulating OBI. We have comprehensively described the HBV cell cycle, cccDNA kinetics, current regulatory mechanisms, and the therapeutic methods of cccDNA in OBI-related diseases.
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Affiliation(s)
- Pei He
- Department of Laboratory Medicine, The First Affiliated Hospital of Anhui Medical University, Hefei, 230012, People's Republic of China
- Anhui Public Health Clinical Center, Hefei, 230012, People's Republic of China
- Department of Infectious Diseases, The Second Hospital of Anhui Medical University, Hefei, China
| | - Peixin Zhang
- Department of Infectious Diseases, The Second Hospital of Anhui Medical University, Hefei, China
| | - Yaping Fang
- Department of Clinical Laboratory, The Second Hospital of Anhui Medical University, Hefei, China
| | - Ning Han
- Department of Clinical Laboratory, The Second Hospital of Anhui Medical University, Hefei, China
| | - Wensu Yang
- Department of Laboratory Medicine, The First Affiliated Hospital of Anhui Medical University, Hefei, 230012, People's Republic of China
- Anhui Public Health Clinical Center, Hefei, 230012, People's Republic of China
| | - Zhaoxin Xia
- Department of Laboratory Medicine, The First Affiliated Hospital of Anhui Medical University, Hefei, 230012, People's Republic of China
- Anhui Public Health Clinical Center, Hefei, 230012, People's Republic of China
| | - Yi Zhu
- Department of Laboratory Medicine, The First Affiliated Hospital of Anhui Medical University, Hefei, 230012, People's Republic of China
- Anhui Public Health Clinical Center, Hefei, 230012, People's Republic of China
| | - Zhenhua Zhang
- Department of Infectious Diseases, The Second Hospital of Anhui Medical University, Hefei, China.
| | - Jilu Shen
- Department of Laboratory Medicine, The First Affiliated Hospital of Anhui Medical University, Hefei, 230012, People's Republic of China.
- Anhui Public Health Clinical Center, Hefei, 230012, People's Republic of China.
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Kazim NA, Lilo KM, Ibraheem SR, Saleh YA, Shabeeb SB. EVALUATION OF SEROLOGICAL SCREENING AND PCR-AMPLIFICATION OF HEPATITIS B VIRUS DNA AMONG IRAQI BLOOD DONORS. WIADOMOSCI LEKARSKIE (WARSAW, POLAND : 1960) 2023; 75:2915-2919. [PMID: 36723303 DOI: 10.36740/wlek202212104] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
OBJECTIVE The aim: Infection with the hepatitis B virus (HBV) caused by blood transfusion is a big problem throughout the world. The aim of study is to determine the faster and more accurate methods for detection of hepatitis B infections by serological screening and PCR- amplification. PATIENTS AND METHODS Materials and methods: A total of 140528 donors were tested for HBsAg and total anti-HBc from January to October 2021 in Iraq's National Blood Transfusion Center; however, only 100 samples with HBsAg (-) and anti-HBc (+) were collected and tested for HBV DNA using quantitative real-time PCR. RESULTS Results: From 2015 to 2021, the percentage of HBsAg positive donors was 0.33 percent in 2015, 0.32 percent in 2016, 0.30 percent in 2017, 0.28 percent in 2018, 0.23 percent in 2019, 0.22 percent in 2020, and 0.27 percent in 2021. Between January and October of 2021, the overall anti-HBc rate among the (140528) donors was 4.42 percent. According to our findings, only 7% of blood samples from NBTC donors with HBsAg (-) anti-HBc (+) were positive for HBV DNA. The results showed no significant change in HBs Ag (+) and total anti-HBc rates among blood donors between 2015 and 2021. CONCLUSION Conclusions: HBV infection could be transmitted from a blood donor with OBI. PCR (RT PCR) is substantially more sensitive and effective. Despite this the use of an anti-HBc test for blood donors could be seen as a second choice to control HBV from spreading during blood transfusions.
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Affiliation(s)
- Noor A Kazim
- BIOTECHNOLOGY DEPARTMENT, COLLEGE OF SCIENCE, UNIVERSITY OF BAGHDAD, BAGHDAD, IRAQ
| | - Kareem M Lilo
- MINISTRY OF HEALTH, NATIONAL CENTER FOR DRUG RESEARCH AND CONTROL, BAGHDAD, IRAQ
| | - Shaima R Ibraheem
- BIOTECHNOLOGY DEPARTMENT, COLLEGE OF SCIENCE, UNIVERSITY OF BAGHDAD, BAGHDAD, IRAQ
| | - Yaqoob A Saleh
- MINISTRY OF HEALTHE, NATIONAL BLOOD TRANSFUSION CENTER, BAGHDAD, IRAQ
| | - Sally B Shabeeb
- MINISTRY OF HEALTHE, NATIONAL BLOOD TRANSFUSION CENTER, BAGHDAD, IRAQ
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Surrogate Markers for Hepatitis B Virus Covalently Closed Circular DNA. Semin Liver Dis 2022; 42:327-340. [PMID: 35445388 DOI: 10.1055/a-1830-2741] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
Chronic infection with the hepatitis B virus (HBV) is one of the most common causes of liver disease worldwide. Chronic HBV infection is currently incurable because of the persistence of the viral template for the viral transcripts, covalently closed circular deoxyribonucleic acid (cccDNA). Detecting changes in cccDNA transcriptional activity is key to understanding fundamental virology, determining the efficacy of new therapies, and deciding the optimal clinical management of HBV patients. In this review, we summarize surrogate circulating biomarkers that have been used to infer cccDNA levels and activity in people with chronic hepatitis B. Moreover, we outline the current shortcomings of the current biomarkers and highlight the clinical importance in improving them and expanding their use.
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Saitta C, Pollicino T, Raimondo G. Occult Hepatitis B Virus Infection: An Update. Viruses 2022; 14:v14071504. [PMID: 35891484 PMCID: PMC9318873 DOI: 10.3390/v14071504] [Citation(s) in RCA: 18] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2022] [Revised: 06/28/2022] [Accepted: 06/29/2022] [Indexed: 11/16/2022] Open
Abstract
Occult hepatitis B virus (HBV) infection (OBI) refers to a condition in which replication-competent viral DNA is present in the liver (with detectable or undetectable HBV DNA in the serum) of individuals testing negative for the HBV surface antigen (HBsAg). In this peculiar phase of HBV infection, the covalently closed circular DNA (cccDNA) is in a low state of replication. Many advances have been made in clarifying the mechanisms involved in such a suppression of viral activity, which seems to be mainly related to the host's immune control and epigenetic factors. OBI is diffused worldwide, but its prevalence is highly variable among patient populations. This depends on different geographic areas, risk factors for parenteral infections, and assays used for HBsAg and HBV DNA detection. OBI has an impact in several clinical contexts: (a) it can be transmitted, causing a classic form of hepatitis B, through blood transfusion or liver transplantation; (b) it may reactivate in the case of immunosuppression, leading to the possible development of even fulminant hepatitis; (c) it may accelerate the progression of chronic liver disease due to different causes toward cirrhosis; (d) it maintains the pro-oncogenic properties of the "overt" infection, favoring the development of hepatocellular carcinoma.
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Affiliation(s)
- Carlo Saitta
- Division of Medicine and Hepatology, University Hospital of Messina, 98124 Messina, Italy;
- Department of Clinical and Experimental Medicine, University of Messina, 98124 Messina, Italy
| | - Teresa Pollicino
- Department of Human Pathology, University Hospital of Messina, 98124 Messina, Italy;
| | - Giovanni Raimondo
- Division of Medicine and Hepatology, University Hospital of Messina, 98124 Messina, Italy;
- Department of Clinical and Experimental Medicine, University of Messina, 98124 Messina, Italy
- Correspondence: ; Tel.: +39-(0)-902212392
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Molecular characteristics of the full-length genome of occult hepatitis B virus from blood donors in China. Sci Rep 2022; 12:8194. [PMID: 35581341 PMCID: PMC9114411 DOI: 10.1038/s41598-022-12288-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2022] [Accepted: 05/06/2022] [Indexed: 11/22/2022] Open
Abstract
The characteristics of a large sample size of the full-length genome of occult hepatitis B virus (HBV) infection (OBI) have not been extensively explored in China. Voluntary blood donors who were HBsAg-negative/HBV NAT-positive (HBsAg−/HBV NAT+) were identified by blood screening and recruited. Blood samples were tested for HBV serologic markers, viral loads, and PCR to identify OBI. HBV full-length genomes were obtained by amplifying two fragments using nested PCR. The characterization of OBI strains was based on sequence analyses compared with HBsAg+ strains obtained from the same donor population. Of the 50 full-length genomes of 172 identified OBI strains, 33 were classified as genotype B (OBIB) and 17 strains as genotype C (OBIC). Significantly higher nucleotide variabilities were observed in the Pre-S2/S promoter region (SP2) and core upstream regulatory sequence (CURS) in OBIB than in their HBsAg+ controls (P < 0.05). Both OBIB and OBIC showed higher amino acid (aa) variabilities in Pol and Pre-S/S regions than their controls (P < 0.05). In addition, 19 novel OBI-related mutations were found spanning the four open reading frames (ORFs) of the HBV genome. Four novel deletions and one novel insertion were also found in OBIC strains. Several novel OBI-related mutations spanning the four ORFs of the virus were identified by characterizing a large sample size of the full-length OBI genome, which may affect the production of HBsAg and contribute to the occult infection of HBV.
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de Almeida NAA, de Paula VS. Occult Hepatitis B virus (HBV) infection and challenges for hepatitis elimination: A literature review. J Appl Microbiol 2021; 132:1616-1635. [PMID: 34724308 DOI: 10.1111/jam.15351] [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: 07/28/2021] [Revised: 09/08/2021] [Accepted: 10/11/2021] [Indexed: 12/15/2022]
Abstract
Occult hepatitis B infection (OBI) is characterized by the detection of hepatitis B virus (HBV) DNA in serum or liver but negativity for hepatitis B surface antigen. OBI, which is thought to be maintained by host, immunological, viral and/or epigenetic factors, is one of the most challenging clinical features in the study of viral hepatitis. Currently, there is no validated detection test for OBI. It is believed that OBI is widely distributed throughout the world, with a higher prevalence in populations at high-risk HBV, but the detailed worldwide prevalence patterns are unknown. We conducted a survey of recently published studies on OBI rates across all continents. High prevalence rates of OBI are observed in some specific groups, including patients with hepatitis C virus, human immunodeficiency virus co-infection or hepatocellular carcinoma. In 2016, the World Health Organization adopted strategies to eliminate viral hepatitis by 2030, but the difficulties in detecting and treating OBI currently challenge this goal. Subjects with OBI can transmit HBV, and episodes of reactivation can occur. Further studies to understanding the mechanisms that drive the development of OBI are needed and can contribute to efforts at eliminating viral hepatitis.
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9
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Zhang D, Guo S, Schrodi SJ. Mechanisms of DNA Methylation in Virus-Host Interaction in Hepatitis B Infection: Pathogenesis and Oncogenetic Properties. Int J Mol Sci 2021; 22:9858. [PMID: 34576022 PMCID: PMC8466338 DOI: 10.3390/ijms22189858] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2021] [Revised: 09/10/2021] [Accepted: 09/10/2021] [Indexed: 12/11/2022] Open
Abstract
Hepatitis B virus (HBV), the well-studied oncovirus that contributes to the majority of hepatocellular carcinomas (HCC) worldwide, can cause a severe inflammatory microenvironment leading to genetic and epigenetic changes in hepatocyte clones. HBV replication contributes to the regulation of DNA methyltransferase gene expression, particularly by X protein (HBx), and subsequent methylation changes may lead to abnormal transcription activation of adjacent genes and genomic instability. Undoubtedly, the altered expression of these genes has been known to cause diverse aspects of infected hepatocytes, including apoptosis, proliferation, reactive oxygen species (ROS) accumulation, and immune responses. Additionally, pollutant-induced DNA methylation changes and aberrant methylation of imprinted genes in hepatocytes also complicate the process of tumorigenesis. Meanwhile, hepatocytes also contribute to epigenetic modification of the viral genome to affect HBV replication or viral protein production. Meanwhile, methylation levels of HBV integrants and surrounding host regions also play crucial roles in their ability to produce viral proteins in affected hepatocytes. Both host and viral changes can provide novel insights into tumorigenesis, individualized responses to therapeutic intervention, disease progress, and early diagnosis. As such, DNA methylation-mediated epigenetic silencing of cancer-related genes and viral replication is a compelling therapeutic goal to reduce morbidity and mortality from liver cancer caused by chronic HBV infection. In this review, we summarize the most recent research on aberrant DNA methylation associated with HBV infection, which is involved in HCC development, and provide an outlook on the future direction of the research.
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Affiliation(s)
- Dake Zhang
- Key Laboratory of Biomechanics and Mechanobiology, Ministry of Education, Beijing Advanced Innovation Center for Biomedical Engineering, School of Biological Science and Medical Engineering, Beihang University, Beijing 100083, China
| | - Shicheng Guo
- Department of Medical Genetics, University of Wisconsin-Madison, Madison, WI 53706, USA;
| | - Steven J. Schrodi
- Department of Medical Genetics, University of Wisconsin-Madison, Madison, WI 53706, USA;
- Computation and Informatics in Biology and Medicine, University of Wisconsin-Madison, Madison, WI 53706, USA
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10
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Olagbenro M, Anderson M, Gaseitsiwe S, Powell EA, Gededzha MP, Selabe SG, Blackard JT. In silico analysis of mutations associated with occult hepatitis B virus (HBV) infection in South Africa. Arch Virol 2021; 166:3075-3084. [PMID: 34468889 DOI: 10.1007/s00705-021-05196-7] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2020] [Accepted: 06/09/2021] [Indexed: 01/02/2023]
Abstract
Occult hepatitis B virus (OBI) infection is defined by the presence of viral DNA in the liver and/or serum in absence of hepatitis B surface antigen (HBsAg). While multiple studies have identified mutations that are associated with OBI, only a small portion of these mutations have been functionally characterized in vitro. Using complementary in silico approaches, the effects of OBI-associated amino acid mutations on HBV protein function in HBV/HIV-positive ART-naïve South Africans were evaluated. Two OBI-associated mutations in the PreS1 region, one in the PreS2 region, and seven in the surface region of subgenotype A1 sequences were identified as deleterious. In subgenotype A2 sequences, 11 OBI-associated mutations in the PreS1 region, seven in the PreS2 region, and 31 in the surface region were identified as deleterious. In the polymerase region, 14 OBI-associated mutations in subgenotype A1 and 71 OBI-associated mutations in subgenotype A2 were identified as deleterious. This study utilized in silico approaches to characterize the likely impact of OBI-associated mutations on viral function, thereby identifying and prioritizing candidates and reducing the significant cost associated with functional studies that are essential for mechanistic studies of the OBI phenotype.
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Affiliation(s)
- Matthew Olagbenro
- Division of Digestive Diseases, University of Cincinnati College of Medicine, ML 0595, Albert Sabin Way, Cincinnati, OH, 45267-0595, USA
| | | | | | - Eleanor A Powell
- Division of Digestive Diseases, University of Cincinnati College of Medicine, ML 0595, Albert Sabin Way, Cincinnati, OH, 45267-0595, USA.,Department of Pathology and Laboratory Medicine, University of Cincinnati College of Medicine, Cincinnati, OH, USA
| | - Maemu P Gededzha
- Department of Molecular Medicine and Haematology, Faculty of Health Sciences, University of Witwatersrand and National Health Laboratory Service, Johannesburg, South Africa.,HIV and Hepatitis Research Unit, Department of Virology, Sefako Makgatho Health Sciences University and National Health Laboratory Service, Pretoria, South Africa
| | - Selokela G Selabe
- HIV and Hepatitis Research Unit, Department of Virology, Sefako Makgatho Health Sciences University and National Health Laboratory Service, Pretoria, South Africa
| | - Jason T Blackard
- Division of Digestive Diseases, University of Cincinnati College of Medicine, ML 0595, Albert Sabin Way, Cincinnati, OH, 45267-0595, USA. .,HIV and Hepatitis Research Unit, Department of Virology, Sefako Makgatho Health Sciences University and National Health Laboratory Service, Pretoria, South Africa.
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Occult hepatitis B infection and hepatocellular carcinoma: Epidemiology, virology, hepatocarcinogenesis and clinical significance. J Hepatol 2020; 73:952-964. [PMID: 32504662 DOI: 10.1016/j.jhep.2020.05.042] [Citation(s) in RCA: 101] [Impact Index Per Article: 25.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/18/2020] [Revised: 05/21/2020] [Accepted: 05/25/2020] [Indexed: 12/12/2022]
Abstract
Occult hepatitis B infection (OBI) refers to a condition where replication-competent HBV DNA is present in the liver, with or without HBV DNA in the blood, in individuals with serum HBsAg negativity assessed by currently available assays. The episomal covalently closed circular DNA (cccDNA) in OBI is in a low replicative state. Viral gene expression is mediated by epigenetic control of HBV transcription, including the HBV CpG island methylation pathway and post-translational modification of cccDNA-bound histone, with a different pattern from patients with chronic HBV infection. The prevalence of OBI varies tremendously across patient populations owing to numerous factors, such as geographic location, assay characteristics, host immune response, coinfection with other viruses, and vaccination status. Apart from the risk of viral reactivation upon immunosuppression and the risk of transmission of HBV, OBI has been implicated in hepatocellular carcinoma (HCC) development in patients with chronic HCV infection, those with cryptogenic or known liver disease, and in patients with HBsAg seroclearance after chronic HBV infection. An increasing number of prospective studies and meta-analyses have reported a higher incidence of HCC in patients with HCV and OBI, as well as more advanced tumour histological grades and earlier age of HCC diagnosis, compared with patients without OBI. The proposed pathogenetic mechanisms of OBI-related HCC include the influence of HBV DNA integration on the hepatocyte cell cycle, the production of pro-oncogenic proteins (HBx protein and mutated surface proteins), and persistent low-grade necroinflammation (contributing to the development of fibrosis and cirrhosis). There remain uncertainties about exactly how, and in what order, these mechanisms drive the development of tumours in patients with OBI.
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12
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Elalfy H, Besheer T, Elhammady D, El Mesery A, Shaltout SW, Abd El-Maksoud M, Amin AI, Bekhit AN, Abd El Aziz M, El-Bendary M. Pathological characterization of occult hepatitis B virus infection in hepatitis C virus-associated or non-alcoholic steatohepatitis-related hepatocellular carcinoma. World J Meta-Anal 2020; 8:67-77. [DOI: 10.13105/wjma.v8.i2.67] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/12/2019] [Revised: 01/08/2020] [Accepted: 04/09/2020] [Indexed: 02/06/2023] Open
Abstract
Occult hepatitis B virus (HBV) infection, by definition, is a state in which infection with this virus does not manifest with the conventional diagnostic laboratory criteria reserved for the obvious form of HBV infection. As a result, occult HBV infection is commonly a surprise finding discovered accidently during the evaluation of other apparent liver diseases, such as hepatitis C virus (HCV) infection or non-alcoholic fatty liver disease and, more importantly, their evolution into life-threatening hepatocellular carcinoma. As infection with HCV and occult HBV is rarely considered when assessing these more obvious conditions, and in an attempt to offer a better understanding of this phenomenon, this study attempted to shed some light onto the uniqueness of occult HBV infection by addressing the natural history of HBV and HCV infections, as well as non-alcoholic fatty liver disease. This was carried out by taking into account the exclusive integration process undertaken by the HBV genome into infected host hepatocytes, with consideration given to conditions which afford reactivation of the occult infection and stress on the molecular mechanisms that underlie occult HBV infection. Finally, the clinical outcome of occult HBV infection and its relation to hepatocellular carcinoma is analyzed.
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Affiliation(s)
- Hatem Elalfy
- Endemic Medicine Department, Faculty of Medicine, Mansoura University, Mansoura 35516, Egypt
| | - Tarek Besheer
- Endemic Medicine Department, Faculty of Medicine, Mansoura University, Mansoura 35516, Egypt
| | - Dina Elhammady
- Endemic Medicine Department, Faculty of Medicine, Mansoura University, Mansoura 35516, Egypt
| | - Ahmed El Mesery
- Endemic Medicine Department, Faculty of Medicine, Mansoura University, Mansoura 35516, Egypt
| | - Shaker Wagih Shaltout
- Tropical Medicine Department, Faculty of Medicine, Port Said University, Port Said 42511, Egypt
| | - Mohamed Abd El-Maksoud
- Endemic Medicine Department, Faculty of Medicine, Mansoura University, Mansoura 35516, Egypt
| | - Ahmed I Amin
- Internal Medicine Department, Faculty of Medicine, Port Said University, Port Said 42511, Egypt
| | - Ahmed Nasr Bekhit
- Tropical Medicine Department, Zagazig General Hospital, Zagazig 44511, Egypt
| | - Mahmoud Abd El Aziz
- Endemic Medicine Department, Faculty of Medicine, Mansoura University, Mansoura 35516, Egypt
| | - Mahmoud El-Bendary
- Endemic Medicine Department, Faculty of Medicine, Mansoura University, Mansoura 35516, Egypt
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13
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Chen L, Huang W, Wang L, Zhang Z, Zhang F, Zheng S, Kong D. The effects of epigenetic modification on the occurrence and progression of liver diseases and the involved mechanism. Expert Rev Gastroenterol Hepatol 2020; 14:259-270. [PMID: 32124651 DOI: 10.1080/17474124.2020.1736042] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Introduction: Epigenetic modification is a type of gene expression and regulation that does not involve changes in DNA sequences. An increasing number of studies have proven that epigenetic modifications play an important role in the occurrence and progression of liver diseases through the gene regulation and protein expressions of hepatocellular lipid metabolism, inflammatory reaction, cell proliferation, and activation, etc.Areas covered: In this study, we elaborated and analyzed the underlying functional mechanism of epigenetic modification in alcoholic liver disease (ALD), nonalcoholic fatty liver disease (NAFLD), liver fibrosis (LF), viral hepatitis, hepatocellular carcinoma (HCC), and research progress of recent years.Expert opinion: The further understanding of epigenetic mechanisms that can regulate gene expression and cell phenotype leads to new insights in epigenetic control of chronic liver disease. Currently, hepatologists are exploring the role of DNA methylation, histone/chromatin modification, and non-coding RNA in specific liver pathology. These findings have led to advances in direct epigenetic biomarker testing of patient tissue or body fluid specimens, as well as quantitative analysis. Based on these findings, drug validation of some targets involved in the epigenetic mechanism of liver disease is gradually being carried out clinically.
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Affiliation(s)
- Liping Chen
- Chinese Medicine Modernization and Big Data Research Center, Nanjing Hospital of Chinese Medicine, Nanjing University of Chinese Medicine, Nanjing, China
| | - Weifang Huang
- Department of Pharmacology, School of Integral Medicine, Nanjing University of Chinese Medicine, Nanjing, China
| | - Ling Wang
- Jiangsu Key Laboratory for Pharmacology and Safety Evaluation of Chinese Materia Medica, Nanjing University of Chinese Medicine, Nanjing, China.,Department of Pharmacology, School of Pharmacy, Nanjing University of Chinese Medicine, Nanjing, China
| | - Zili Zhang
- Jiangsu Key Laboratory for Pharmacology and Safety Evaluation of Chinese Materia Medica, Nanjing University of Chinese Medicine, Nanjing, China.,Department of Pharmacology, School of Pharmacy, Nanjing University of Chinese Medicine, Nanjing, China
| | - Feng Zhang
- Jiangsu Key Laboratory for Pharmacology and Safety Evaluation of Chinese Materia Medica, Nanjing University of Chinese Medicine, Nanjing, China.,Department of Pharmacology, School of Pharmacy, Nanjing University of Chinese Medicine, Nanjing, China
| | - Shizhong Zheng
- Jiangsu Key Laboratory for Pharmacology and Safety Evaluation of Chinese Materia Medica, Nanjing University of Chinese Medicine, Nanjing, China.,Department of Pharmacology, School of Pharmacy, Nanjing University of Chinese Medicine, Nanjing, China
| | - Desong Kong
- Chinese Medicine Modernization and Big Data Research Center, Nanjing Hospital of Chinese Medicine, Nanjing University of Chinese Medicine, Nanjing, China
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14
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Zhu A, Liao X, Li S, Zhao H, Chen L, Xu M, Duan X. HBV cccDNA and Its Potential as a Therapeutic Target. J Clin Transl Hepatol 2019; 7:258-262. [PMID: 31608218 PMCID: PMC6783673 DOI: 10.14218/jcth.2018.00054] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/26/2018] [Revised: 04/02/2019] [Accepted: 07/10/2019] [Indexed: 12/13/2022] Open
Abstract
Chronic hepatitis B virus 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. Covalently closed circular DNA in the nucleus of infected cells cannot be disabled by present therapies which may lead to HBV persistence and relapse. In this review, we summarized the current knowledge on hepatitis B virus covalently closed circular DNA and its potential role as a therapeutic target.
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Affiliation(s)
| | | | | | | | | | - Min Xu
- Correspondence to: Min Xu and Xiaoqiong Duan, Institute of Blood Transfusion, Chinese Academy of Medical Sciences and Peking Union Medical College, Chengdu 610052, China. Tel: +86-135-4080-7307, E-mail: (MX) or (XD)
| | - Xiaoqiong Duan
- Correspondence to: Min Xu and Xiaoqiong Duan, Institute of Blood Transfusion, Chinese Academy of Medical Sciences and Peking Union Medical College, Chengdu 610052, China. Tel: +86-135-4080-7307, E-mail: (MX) or (XD)
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15
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Mogul DB, Brereton N, Carson KA, Pittarelli M, Daniel H, Torbenson M, Schwarz KB. Development of a Dietary Methyl Donor Food Frequency Questionnaire to Assess Folate and Vitamin B 12 Status in Children with Chronic Hepatitis B Virus Infection. J Pediatr 2018; 203:41-46.e2. [PMID: 30243534 DOI: 10.1016/j.jpeds.2018.07.088] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/04/2018] [Revised: 07/10/2018] [Accepted: 07/26/2018] [Indexed: 10/28/2022]
Abstract
OBJECTIVE To develop a dietary methyl donor food frequency questionnaire (DMD-FFQ) that is validated in a cohort of US children and to determine whether the consumption of folate and vitamin B12, principal DMDs, correlates with HBV DNA levels and its methylation density. STUDY DESIGN We developed a semiquantitative DMD-FFQ to estimate intake of folate and vitamin B12 and validated this instrument against a 24-hour dietary recall and biomarkers-red blood cell folate, serum vitamin B12, and homocysteine-in 35 children with chronic HBV infection without other medical comorbidities. Estimates of DMD, as well as the serum biomarkers, were correlated with the methylation density of HBV CpG island 2 and HBV DNA levels. RESULTS Folate per kilogram of body weight by the DMD-FFQ correlated positively with 24-hour recall (r = 0.60; P < .001) and red blood cell folate (r = 0.40; P = .02), and negatively with homocysteine (r = -0.54; P < .001). Vitamin B12 per kilogram by DMD-FFQ also correlated positively with 24-hour recall (r = 0.57; P < .001) and serum vitamin B12 (r = 0.36, P = .04), and negatively with homocysteine (r = -0.44; P = .008). Neither DMD intake (from DMD-FFQ or 24-hour recall) nor serum biomarkers correlated with HBV DNA levels or its methylation density. CONCLUSIONS Our DMD-FFQ correlates well with a 24-hour recall and circulating biomarkers. Although little evidence existed that consumption of these micronutrients correlated with HBV replication, this tool could prove useful for investigating epigenetic modification by diet for several pediatric diseases.
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Affiliation(s)
- Douglas B Mogul
- Division of Pediatric Gastroenterology, Hepatology and Nutrition, Johns Hopkins University School of Medicine, Baltimore, MD.
| | - Nga Brereton
- Institute for Clinical and Translational Research, Johns Hopkins University School of Medicine, Baltimore, MD
| | - Kathryn A Carson
- Institute for Clinical and Translational Research, Johns Hopkins University School of Medicine, Baltimore, MD; Department of Epidemiology, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD
| | - Maria Pittarelli
- Institute for Clinical and Translational Research, Johns Hopkins University School of Medicine, Baltimore, MD
| | - Hubert Daniel
- Department of Pathology, Johns Hopkins Hospital, Baltimore, MD
| | | | - Kathleen B Schwarz
- Division of Pediatric Gastroenterology, Hepatology and Nutrition, Johns Hopkins University School of Medicine, Baltimore, MD
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16
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Anderson M, Choga WT, Moyo S, Bell TG, Mbangiwa T, Phinius BB, Bhebhe L, Sebunya TK, Makhema J, Marlink R, Kramvis A, Essex M, Musonda RM, Blackard JT, Gaseitsiwe S. In Silico Analysis of Hepatitis B Virus Occult Associated Mutations in Botswana Using a Novel Algorithm. Genes (Basel) 2018; 9:genes9090420. [PMID: 30134551 PMCID: PMC6162659 DOI: 10.3390/genes9090420] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2018] [Accepted: 08/16/2018] [Indexed: 02/06/2023] Open
Abstract
Occult hepatitis B infections (OBI) represent a reservoir of undiagnosed and untreated hepatitis B virus (HBV), hence the need to identify mutations that lead to this phenotype. Functionally characterizing these mutations by in vitro studies is time-consuming and expensive. To bridge this gap, in silico approaches, which predict the effect of amino acid (aa) variants on HBV protein function, are necessary. We developed an algorithm for determining the relevance of OBI-associated mutations using in silico approaches. A 3 kb fragment of subgenotypes A1 and D3 from 24 chronic HBV-infected (CHB) and 24 OBI participants was analyzed. To develop and validate the algorithm, the effects of 68 previously characterized occult-associated mutations were determined using three computational tools: PolyPhen2, SNAP2, and PROVEAN. The percentage of deleterious mutations (with impact on protein function) predicted were 52 (76.5%) by PolyPhen2, 55 (80.9%) by SNAP2, and 65 (95.6%) by PROVEAN. At least two tools correctly predicted 59 (86.8%) mutations as deleterious. To identify OBI-associated mutations exclusive to Botswana, study sequences were compared to CHB sequences from GenBank. Of the 43 OBI-associated mutations identified, 26 (60.5%) were predicted by at least two tools to have an impact on protein function. To our knowledge, this is the first study to use in silico approaches to determine the impact of OBI-associated mutations, thereby identifying potential candidates for functional analysis to facilitate mechanistic studies of the OBI phenotype.
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Affiliation(s)
- Motswedi Anderson
- Botswana Harvard AIDS Institute Partnership, Gaborone, Botswana.
- Faculty of Science, Department of Biological Sciences, University of Botswana, Gaborone, Botswana.
| | | | - Sikhulile Moyo
- Botswana Harvard AIDS Institute Partnership, Gaborone, Botswana.
- Department of Immunology and Infectious Diseases, Harvard T.H. Chan School of Public Health, Boston, MA 02115, USA.
| | - Trevor Graham Bell
- Hepatitis Virus Diversity Research Unit (HVDRU), Faculty of Health Sciences, Department of Internal Medicine, School of Clinical Medicine, University of the Witwatersrand, Johannesburg 2050, South Africa.
| | - Tshepiso Mbangiwa
- Botswana Harvard AIDS Institute Partnership, Gaborone, Botswana.
- Faculty of Allied Health Sciences, University of Botswana, Gaborone, Botswana.
| | - Bonolo B Phinius
- Botswana Harvard AIDS Institute Partnership, Gaborone, Botswana.
| | - Lynette Bhebhe
- Botswana Harvard AIDS Institute Partnership, Gaborone, Botswana.
| | - Theresa K Sebunya
- Faculty of Science, Department of Biological Sciences, University of Botswana, Gaborone, Botswana.
| | - Joseph Makhema
- Botswana Harvard AIDS Institute Partnership, Gaborone, Botswana.
- Department of Immunology and Infectious Diseases, Harvard T.H. Chan School of Public Health, Boston, MA 02115, USA.
| | - Richard Marlink
- Botswana Harvard AIDS Institute Partnership, Gaborone, Botswana.
- Department of Immunology and Infectious Diseases, Harvard T.H. Chan School of Public Health, Boston, MA 02115, USA.
- Rutgers Global Health Institute, Robert Wood Johnson Medical School, Rutgers University, New Brunswick, NJ 08854, USA.
| | - Anna Kramvis
- Hepatitis Virus Diversity Research Unit (HVDRU), Faculty of Health Sciences, Department of Internal Medicine, School of Clinical Medicine, University of the Witwatersrand, Johannesburg 2050, South Africa.
| | - Max Essex
- Botswana Harvard AIDS Institute Partnership, Gaborone, Botswana.
- Department of Immunology and Infectious Diseases, Harvard T.H. Chan School of Public Health, Boston, MA 02115, USA.
| | | | - Jason T Blackard
- College of Medicine, University of Cincinnati, Cincinnati, OH 45267, USA.
| | - Simani Gaseitsiwe
- Botswana Harvard AIDS Institute Partnership, Gaborone, Botswana.
- Department of Immunology and Infectious Diseases, Harvard T.H. Chan School of Public Health, Boston, MA 02115, USA.
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17
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Goyal A, Chauhan R. The dynamics of integration, viral suppression and cell-cell transmission in the development of occult Hepatitis B virus infection. J Theor Biol 2018; 455:269-280. [PMID: 29969598 DOI: 10.1016/j.jtbi.2018.06.020] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2018] [Revised: 06/20/2018] [Accepted: 06/25/2018] [Indexed: 12/15/2022]
Abstract
BACKGROUND Out of several phases of HBV infection, the least understood phase is occult hepatitis B virus infection. The paucity of data due to non-availability of biological tissues and the prerequisite of ultra-sensitive assays for the detection of occult hepatitis B virus infection prompted us to utilize mathematical modeling in determining mechanisms that lead to occult hepatitis B virus infection and characteristics of HBV infection during occult hepatitis B virus infection. METHODS We proposed two mathematical models (M1 and M2), considering two different phenomenon for episomal maintenance and accumulation of covalently closed circular DNA (cccDNA) in infected hepatocytes: (i) M1 - recirculation of the relaxed circular DNA/double-stranded linear DNA from cytoplasm to the nucleus, and (ii) M2 - reinfection of infected hepatocytes with virions. We further incorporated the dynamics of integrated Hepatitis B virus DNA (iHBV) to investigate its role in the development of occult hepatitis B virus infection. RESULTS The analysis showed that the main mechanism for the spread of infection during occult hepatitis B virus infection is cell-to-cell transmission and not cell-free virus transmission. A significant viral suppression (of at least 99% from its peak production values) was essential but not sufficient in the development of occult hepatitis B virus infection under M1; however under M2, the viral suppression was neither sufficient nor essential as the inhibition of the production of HBsAg without viral suppression can also explain the development of occult hepatitis B virus infection. Our analysis also revealed that occult hepatitis B virus infection seropositive cases are more likely to progress into liver cirrhosis compared to occult hepatitis B virus infection seronegative cases. The iHBV was found to be mostly silent (by either being absent or non-productive for HBsAg) during occult hepatitis B virus infection. CONCLUSION The viral suppression is neither essential nor sufficient to explain the development of occult hepatitis B virus infection on its own. Not only the viral suppression but the inhibition -of the production and the export of HBsAg from cccDNA and iHBV also plays an important role in the development of occult hepatitis B virus infection. This is the first study, which incorporates the dynamics of iHBV and shows that HBV primarily spreads via cell-cell transmission during occult hepatitis B virus infection.
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Affiliation(s)
- Ashish Goyal
- Theoretical Biology and Biophysics, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA.
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18
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Chang CY, Chang FL, Chiang CW, Lo YN, Lin TY, Chen WC, Tsai KC, Lee YC. Interaction of S17 Antibody with the Functional Binding Region of the Hepatitis B Virus Pre-S2 Epitope. Viral Immunol 2018; 31:492-499. [PMID: 29847243 DOI: 10.1089/vim.2017.0200] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
To understand the mechanism for inhibition of hepatitis B virus (HBV) infection is important. In this study, single-chain variable fragment (scFv) antibodies were generated and directed to the pre-S2 epitope of HBV surface antigen (HBsAg). These human scFvs were isolated from a person with history of HBV infection by phage display technology. An evaluation of panning efficiency revealed that the eluted phage titer was increased, indicating that specific clones were enriched after panning. Selected scFvs were characterized with the recombinant HBsAg through Western blotting and enzyme-linked immunosorbent assay to confirm the binding ability. Flow cytometry analysis and immunocytochemical staining revealed that one scFv, S17, could recognize endogenous HBsAg expressed on the HepG2215 cell membrane. Moreover, the binding affinity of scFv S17 to the pre-S2 epitope was determined to be 4.2 × 10-8 M. Two ion interactions were observed as the major driving forces for scFv S17 interacting with pre-S2 by performing a rational molecular docking analysis. This study provides insights into the structural basis to understand the interactions between an antibody and the pre-S2 epitope. The functional scFv format can potentially be used in future immunotherapeutic applications.
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Affiliation(s)
- Chang-Yu Chang
- 1 Department of Medical Technology, Jen-Teh Junior College of Medicine , Nursing and Management, Miaoli, Taiwan
| | - Fu-Ling Chang
- 2 The Ph.D. Program for Cancer Molecular Biology and Drug Discovery, College of Medical Science and Technology, Taipei Medical University , Taipei, Taiwan
| | - Chen-Wei Chiang
- 3 Research Center of Cancer Translational Medicine, Taipei Medical University , Taipei, Taiwan
| | - Yan-Ni Lo
- 3 Research Center of Cancer Translational Medicine, Taipei Medical University , Taipei, Taiwan
| | - Tsai-Yu Lin
- 3 Research Center of Cancer Translational Medicine, Taipei Medical University , Taipei, Taiwan
| | - Wang-Chuan Chen
- 4 The School of Chinese Medicine for Post Baccalaureate, I-Shou University , Kaohsiung, Taiwan .,5 Department of Chinese Medicine, E-Da Hospital , Kaohsiung, Taiwan
| | - Keng-Chang Tsai
- 6 The Ph.D. Program for Medical Biotechnology, College of Medical Science and Technology, Taipei Medical University , Taipei, Taiwan .,7 National Research Institute of Chinese Medicine , Ministry of Health and Welfare, Taipei, Taiwan
| | - Yu-Ching Lee
- 2 The Ph.D. Program for Cancer Molecular Biology and Drug Discovery, College of Medical Science and Technology, Taipei Medical University , Taipei, Taiwan .,3 Research Center of Cancer Translational Medicine, Taipei Medical University , Taipei, Taiwan
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19
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Bloom K, Maepa MB, Ely A, Arbuthnot P. Gene Therapy for Chronic HBV-Can We Eliminate cccDNA? Genes (Basel) 2018; 9:E207. [PMID: 29649127 PMCID: PMC5924549 DOI: 10.3390/genes9040207] [Citation(s) in RCA: 47] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2018] [Revised: 04/05/2018] [Accepted: 04/09/2018] [Indexed: 02/06/2023] Open
Abstract
Chronic infection with the hepatitis B virus (HBV) is a global health concern and accounts for approximately 1 million deaths annually. Amongst other limitations of current anti-HBV treatment, failure to eliminate the viral covalently closed circular DNA (cccDNA) and emergence of resistance remain the most worrisome. Viral rebound from latent episomal cccDNA reservoirs occurs following cessation of therapy, patient non-compliance, or the development of escape mutants. Simultaneous viral co-infections, such as by HIV-1, further complicate therapeutic interventions. These challenges have prompted development of novel targeted hepatitis B therapies. Given the ease with which highly specific and potent nucleic acid therapeutics can be rationally designed, gene therapy has generated interest for antiviral application. Gene therapy strategies developed for HBV include gene silencing by harnessing RNA interference, transcriptional inhibition through epigenetic modification of target DNA, genome editing by designer nucleases, and immune modulation with cytokines. DNA-binding domains and effectors based on the zinc finger (ZF), transcription activator-like effector (TALE), and clustered regularly interspaced short palindromic repeat (CRISPR) systems are remarkably well suited to targeting episomal cccDNA. This review discusses recent developments and challenges facing the field of anti-HBV gene therapy, its potential curative significance and the progress towards clinical application.
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Affiliation(s)
- Kristie Bloom
- Wits/SAMRC Antiviral Gene Therapy Research Unit, School of Pathology, Faculty of Health Sciences, University of the Witwatersrand, Private Bag 3, Johannesburg, WITS 2050, South Africa.
| | - Mohube Betty Maepa
- Wits/SAMRC Antiviral Gene Therapy Research Unit, School of Pathology, Faculty of Health Sciences, University of the Witwatersrand, Private Bag 3, Johannesburg, WITS 2050, South Africa.
| | - Abdullah Ely
- Wits/SAMRC Antiviral Gene Therapy Research Unit, School of Pathology, Faculty of Health Sciences, University of the Witwatersrand, Private Bag 3, Johannesburg, WITS 2050, South Africa.
| | - Patrick Arbuthnot
- Wits/SAMRC Antiviral Gene Therapy Research Unit, School of Pathology, Faculty of Health Sciences, University of the Witwatersrand, Private Bag 3, Johannesburg, WITS 2050, South Africa.
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20
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Kostyushev DS, Zueva AP, Brezgin SA, Lipatnikov AD, Volchkova EV, Maleyev VV, Chulanov VP. THE ROLE OF DNA-METHYLTRANSFERASES IN THE LIFE CYCLE OF HEPATITIS B VIRUS AND PATHOGENESIS OF CHRONIC HEPATITIS B. Vopr Virusol 2018; 63:19-29. [PMID: 36494993 DOI: 10.18821/0507-4088-2018-63-1-19-29] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2020] [Indexed: 12/13/2022]
Abstract
Chronic hepatitis B is caused by a persistent form of hepatitis B virus, covalently closed circular DNA (cccDNA). Stability of cccDNA is associated with intracellular localization of cccDNA and formation of minichromosome, regulated by epigenetic mechanisms. One of the key mechanisms in epigenetics is methylation of DNA on CpG islands. Expression levels of DNA-methyltransferases (DNMTs) in chronic hepatitis B patients were shown to be upregulated. Nevertheless, the role of DNMTs in the life cycle of HBV and their effects on the cell remain elusive. In this review, we discuss latest achievements on the role of DNMTs in chronic hepatitis B and HBV in vitro models.
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Affiliation(s)
| | - A P Zueva
- Central Research Institute of Epidemiology.,M.V. Lomonosov Moscow State University
| | - S A Brezgin
- Central Research Institute of Epidemiology.,I.M. Sechenov First State Medical University
| | - A D Lipatnikov
- Central Research Institute of Epidemiology.,D.I. Mendeleev University of Chemical Technology of Russia
| | | | | | - V P Chulanov
- Central Research Institute of Epidemiology.,I.M. Sechenov First State Medical University
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21
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Occult Hepatitis B Virus Infection and Associated Genotypes among HBsAg-negative Subjects in Burkina Faso. Mediterr J Hematol Infect Dis 2018; 10:e2018007. [PMID: 29326804 PMCID: PMC5760064 DOI: 10.4084/mjhid.2018.007] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2017] [Accepted: 12/15/2017] [Indexed: 12/11/2022] Open
Abstract
Background The presence of HBV DNA in the liver (with detectable or undetectable HBV DNA in the serum) of individuals tested HBsAg negative by currently available assays is defined occult B Infection (OBI). It remains a potential transmission threat and risk to HBV chronic infection. The purpose of this study was to determine the OBI prevalence among HBsAg negative subjects and to characterize associated genotypes. Methods Blood samples of 219 HBsAg-negative subjects tested by ELISA were collected. HBV DNA was investigated in all samples. Viral loads were determined using quantitative real-time PCR. All samples were screened for HBV markers (anti-HBc, anti-HBe, HBsAg). The Pre-S/S region of the HBV genome was sequenced. The database was analyzed using the SPSS and Epi info software. Phylogenetic analysis was performed using the BioEdit and MEGA software. Results Of the 219 samples, 20.1% were anti-HBc positive, 1.8% HBeAg and 22.8% were anti-HBe positive. Fifty-six (56) (25.6%) of the samples had a detectable HBV DNA and viral loads ranging from 4 IU/mL to 13.6 106 IU/mL. Sixteen of them (16/56) had a viral load < 200 IU/mL, resulting in an OBI prevalence of 7.3% (16/219) in our study. The remaining 40 subjects had viral loads > 200 IU/mL, resulting in a “false OBI” prevalence of 18.3% (40/219). HBV genotype E was predominant followed by the quasi-sub-genotype A3. A single “false OBI” strain had the characteristic mutation G145R. Other mutations were observed and all located in the major hydrophilic region (MHR) of the S gene. Conclusion The study reported a prevalence of 7.3% of occult hepatitis B infection. It confirms the predominance of genotype E and the existence of a subgroup of quasi-sub-genotype A3 of HBV in Burkina Faso. It further provides information on the presence of “false OBI.” This study has found mutations in the major hydrophilic region (MHR) of the pre-S/S gene of HBV.
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22
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Amponsah-Dacosta E, Selabe SG, Mphahlele MJ. Evolution of the serologic and virologic course of occult HBV infection in therapy experienced HIV co-infected patients. J Med Virol 2017; 90:291-303. [PMID: 28971485 DOI: 10.1002/jmv.24956] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2017] [Accepted: 09/16/2017] [Indexed: 02/06/2023]
Abstract
We investigated how the natural course of occult hepatitis B virus (HBV) infection (OBI) may evolve during HIV co-infection and long term HBV-active HAART. From a cohort of 181 HIV infected patients who were consecutively recruited over a 5 year period, 28 HBV co-infected patients with sequential sera (n = 98) were identified. Iterative HBV serology and viral loads were determined before and during treatment. The viral HBsAg gene was then serially amplified, directly sequenced, and molecularly characterized. Persistent detection of anti-HBs did not result in a modification to the clinical course of OBI. In contrast, reactivation of chronic HBV infection, hepatic enzymatic flares and cases of HBV reinfection were evident among anti-HBs negative OBI patients, and this was a notable finding. Of the 14 chronic HBV infected patients, eight progressed to persistent OBI after initiation of HBV-active HAART, increasing the number of patients with OBI in the study. Long term HBV-active HAART was not found to have a notable impact on low level viremia during OBI. While the HBsAg gene sequences isolated from chronic HBV infection were genetically stable over time, OBI-associated variants (sP111R, sT127P, sY161F) were neither stable nor predominant during the course of infection. This study is the first of its kind from South Africa to show the occurrence of hepatic enzymatic flares, HBV reactivation, and reinfection in HAART-exposed HIV co-infected patients with OBI. Among the cases studied, there was further evidence that OBI-associated variants may not play a significant role in the pathogenesis of OBI.
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Affiliation(s)
- Edina Amponsah-Dacosta
- HIV and Hepatitis Research Unit, Department of Virology, Sefako Makgatho Health Sciences University and National Health Laboratory Service, Medunsa, Pretoria, South Africa
| | - Selokela G Selabe
- HIV and Hepatitis Research Unit, Department of Virology, Sefako Makgatho Health Sciences University and National Health Laboratory Service, Medunsa, Pretoria, South Africa
| | - Maphahlaganye J Mphahlele
- HIV and Hepatitis Research Unit, Department of Virology, Sefako Makgatho Health Sciences University and National Health Laboratory Service, Medunsa, Pretoria, South Africa.,South African Medical Research Council, Pretoria, South Africa
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Rendon JC, Cortes-Mancera F, Restrepo-Gutierrez JC, Hoyos S, Navas MC. Molecular characterization of occult hepatitis B virus infection in patients with end-stage liver disease in Colombia. PLoS One 2017; 12:e0180447. [PMID: 28686707 PMCID: PMC5501523 DOI: 10.1371/journal.pone.0180447] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2017] [Accepted: 06/15/2017] [Indexed: 12/11/2022] Open
Abstract
Background Hepatitis B virus (HBV) occult infection (OBI) is a risk factor to be taken into account in transfusion, hemodialysis and organ transplantation. The aim of this study was to identify and characterize at the molecular level OBI cases in patients with end-stage liver disease. Methods Sixty-six liver samples were obtained from patients with diagnosis of end-stage liver disease submitted to liver transplantation in Medellin (North West, Colombia). Samples obtained from patients who were negative for the surface antigen of HBV (n = 50) were tested for viral DNA detection by nested PCR for ORFs S, C, and X and confirmed by Southern-Blot. OBI cases were analyzed by sequencing the viral genome to determine the genotype and mutations; additionally, viral genome integration events were examined by the Alu-PCR technique. Results In five cases out of 50 patients (10%) the criteria for OBI was confirmed. HBV genotype F (subgenotypes F1 and F3), genotype A and genotype D were characterized in liver samples. Three integration events in chromosomes 5q14.1, 16p13 and 20q12 affecting Receptor-type tyrosine-protein phosphatase T, Ras Protein Specific Guanine Nucleotide Releasing Factor 2, and the zinc finger 263 genes were identified in two OBI cases. Sequence analysis of the viral genome of the 5 OBI cases showed several punctual missense and nonsense mutations affecting ORFs S, P, Core and X. Conclusions This is the first characterization of OBI in patients with end-stage liver disease in Colombia. The OBI cases were identified in patients with HCV infection or cryptogenic cirrhosis. The integration events (5q14.1, 16p13 and 20q12) described in this study have not been previously reported. Further studies are required to validate the role of mutations and integration events in OBI pathogenesis.
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Affiliation(s)
- Julio Cesar Rendon
- Grupo de Gastrohepatologia, Facultad de Medicina, Universidad de Antioquia, UdeA, Medellin, Colombia
| | - Fabian Cortes-Mancera
- Grupo de Investigación e Innovacion Biomédica GIB, Facultad de Ciencias Exactas y Aplicadas, Instituto Tecnologico Metropolitano (ITM), Medellin, Colombia
| | - Juan Carlos Restrepo-Gutierrez
- Grupo de Gastrohepatologia, Facultad de Medicina, Universidad de Antioquia, UdeA, Medellin, Colombia
- Unidad de Hepatologia y Trasplante Hepatico, Hospital Pablo Tobon Uribe, Medellin, Colombia
| | - Sergio Hoyos
- Grupo de Gastrohepatologia, Facultad de Medicina, Universidad de Antioquia, UdeA, Medellin, Colombia
- Unidad de Hepatologia y Trasplante Hepatico, Hospital Pablo Tobon Uribe, Medellin, Colombia
| | - Maria-Cristina Navas
- Grupo de Gastrohepatologia, Facultad de Medicina, Universidad de Antioquia, UdeA, Medellin, Colombia
- * E-mail:
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24
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Hensel KO, Rendon JC, Navas MC, Rots MG, Postberg J. Virus-host interplay in hepatitis B virus infection and epigenetic treatment strategies. FEBS J 2017; 284:3550-3572. [PMID: 28457020 DOI: 10.1111/febs.14094] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2017] [Revised: 03/25/2017] [Accepted: 04/26/2017] [Indexed: 12/11/2022]
Abstract
Worldwide, chronic hepatitis B virus (HBV) infection is a major health problem and no cure exists. Importantly, hepatocyte intrusion by HBV particles results in a complex deregulation of both viral and host cellular genetic and epigenetic processes. Among the attempts to develop novel therapeutic approaches against HBV infection, several options targeting the epigenomic regulation of HBV replication are gaining attention. These include the experimental treatment with 'epidrugs'. Moreover, as a targeted approach, the principle of 'epigenetic editing' recently is being exploited to control viral replication. Silencing of HBV by specific rewriting of epigenetic marks might diminish viral replication, viremia, and infectivity, eventually controlling the disease and its complications. Additionally, epigenetic editing can be used as an experimental tool to increase our limited understanding regarding the role of epigenetic modifications in viral infections. Aiming for permanent epigenetic reprogramming of the viral genome without unspecific side effects, this breakthrough may pave the roads for an ambitious technological pursuit: to start designing a curative approach utilizing manipulative molecular therapies for viral infections in vivo.
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Affiliation(s)
- Kai O Hensel
- HELIOS Medical Centre Wuppertal, Paediatrics Centre, Centre for Clinical & Translational Research (CCTR), Faculty of Health, Centre for Biomedical Education & Research (ZBAF), Witten/Herdecke University, Germany
| | - Julio C Rendon
- Epigenetic Editing, Department of Pathology and Medical Biology, University of Groningen, University Medical Center Groningen (UMCG), The Netherlands.,Grupo de Gastrohepatologia, Facultad de Medicina, Universidad de Antioquia (UdeA), Medellin, Colombia
| | - Maria-Cristina Navas
- Grupo de Gastrohepatologia, Facultad de Medicina, Universidad de Antioquia (UdeA), Medellin, Colombia
| | - Marianne G Rots
- Epigenetic Editing, Department of Pathology and Medical Biology, University of Groningen, University Medical Center Groningen (UMCG), The Netherlands
| | - Jan Postberg
- HELIOS Medical Centre Wuppertal, Paediatrics Centre, Centre for Clinical & Translational Research (CCTR), Faculty of Health, Centre for Biomedical Education & Research (ZBAF), Witten/Herdecke University, Germany
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25
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Makvandi M. Update on occult hepatitis B virus infection. World J Gastroenterol 2016; 22:8720-8734. [PMID: 27818588 PMCID: PMC5075547 DOI: 10.3748/wjg.v22.i39.8720] [Citation(s) in RCA: 102] [Impact Index Per Article: 12.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/28/2016] [Revised: 06/13/2016] [Accepted: 07/20/2016] [Indexed: 02/06/2023] Open
Abstract
The event of mutations in the surface antigen gene of hepatitis B virus (HBV) results in undetectable hepatitis B surface antigen with positive/negative anti-hepatitis B core (anti-HBc) antibody status in serum and this phenomenon is named occult hepatitis B infection (OBI). The presence of anti-HBc antibody in serum is an important key for OBI tracking, although about 20% of OBI cases are negative for anti-HBc antibody. The diagnosis of OBI is mainly based on polymerase chain reaction (PCR) and real-time PCR assays. However, real-time PCR is a more reliable method than PCR. OBI is a great issue for the public health problem and a challenge for the clinical entity worldwide. The persistence of OBI may lead to the development of cirrhosis and hepatocellular carcinoma. With regard to OBI complications, the screening of HBV DNA by the highly sensitive molecular means should be implemented for: (1) patients with a previous history of chronic or acute HBV infection; (2) patients co-infected with hepatitis C virus/human immunodeficiency virus; (3) patients undergoing chemotherapy or anti-CD20 therapy; (4) recipients of organ transplant; (5) blood donors; (6) organ transplant donors; (7) thalassemia and hemophilia patients; (8) health care workers; (9) patients with liver related disease (cryptogenic); (10) hemodialysis patients; (11) patients undergoing lamivudine or interferon therapy; and (12) children in time of HBV vaccination especially in highly endemic areas of HBV. Active HBV vaccination should be implemented for the close relatives of patients who are negative for OBI markers. Thus, the goal of this review is to evaluate the rate of OBI with a focus on status of high risk groups in different regions of the world.
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26
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Chen J, Liu Y, Zhao J, Xu Z, Chen R, Si L, Lu S, Li X, Wang S, Zhang K, Li J, Han J, Xu D. Characterization of Novel Hepatitis B Virus PreS/S-Gene Mutations in a Patient with Occult Hepatitis B Virus Infection. PLoS One 2016; 11:e0155654. [PMID: 27182775 PMCID: PMC4868315 DOI: 10.1371/journal.pone.0155654] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2015] [Accepted: 05/02/2016] [Indexed: 12/19/2022] Open
Abstract
Objective The impact of hepatitis B virus (HBV) preS/S-gene mutations on occult HBV infection (OBI) is not fully understood. This study characterized multiple novel HBV preS/S-gene mutants obtained from an OBI patient. Methods PreS/S-gene mutants were analyzed by clonal sequencing. Viral replication and expression were analyzed by transfecting HBV genomic recombinants into HepG2 cells. Results Twenty-one preS/S-gene mutants were cloned from four sequential serum samples, including 13 mutants that were not previously documented: (1) sI/T126V+sG145R; (2) preS1 nt 3014−3198 deletion; (3) preS1 nt 3046−3177 deletion; (4) preS1 nt 3046−3177 deletion+s115−116 “INGTST” insertion; (5) preS1 nt 3046−3177 deletion+s115−116 “INGTST” insertion+sG145R; (6) preS1 nt 3115−3123 deletion+sQ129N; (7) preS1 nt 3115−3123 deletion+s126−127 “RPCMNCTI” insertion; (8) s115−116 “INGTST” insertion; (9) s115−116 “INGTST” insertion+sG145R; (10) s126−127 “RPCMNCTI” insertion; (11) preS1 nt 2848−2862 deletion+preS2 initiation codon M→I; (12) s122−123 “KSTGLCK” insertion+sQ129N; and (13) preS2 initiation codon M→I+s131−133TSM→NST. The proportion of preS1 nt 3046−3177 deletion and preS2 initiation codon M→I+s131−133TSM→NST mutants increased in the viral pool with prolonged disease. The 13 novel OBI-related mutants showed a 51.2−99.9% decrease in HBsAg levels compared with that of the wild type. Additional N-glycosylation-associated mutations, sQ129N and s131−133TSM→NST, but not s126−127 “RPCMNCTI,” greatly attenuated anti-HBs binding to HBsAg. Compared with the wild type, replication and surface antigen promoter II activity of the preS1 nt 3046−3177 deletion mutant decreased by 43.3% and 97.0%, respectively. Conclusion PreS/S-gene mutations may play coordinated roles in the presentation of OBI and might be associated with disease progression. This has implications for HBV diagnosis and vaccine improvement.
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Affiliation(s)
- Jianhong Chen
- Institute of Infectious Diseases/Research Center for Clinical and Translational Medicine, Beijing 302 Hospital, Beijing 100039, China
| | - Yan Liu
- Institute of Infectious Diseases/Research Center for Clinical and Translational Medicine, Beijing 302 Hospital, Beijing 100039, China
| | - Jun Zhao
- Institute of Infectious Diseases/Research Center for Clinical and Translational Medicine, Beijing 302 Hospital, Beijing 100039, China
| | - Zhihui Xu
- Institute of Infectious Diseases/Research Center for Clinical and Translational Medicine, Beijing 302 Hospital, Beijing 100039, China
| | - Rongjuan Chen
- Institute of Infectious Diseases/Research Center for Clinical and Translational Medicine, Beijing 302 Hospital, Beijing 100039, China
| | - Lanlan Si
- Institute of Infectious Diseases/Research Center for Clinical and Translational Medicine, Beijing 302 Hospital, Beijing 100039, China
| | - Shanshan Lu
- Institute of Infectious Diseases/Research Center for Clinical and Translational Medicine, Beijing 302 Hospital, Beijing 100039, China
| | - Xiaodong Li
- Institute of Infectious Diseases/Research Center for Clinical and Translational Medicine, Beijing 302 Hospital, Beijing 100039, China
| | - Shuai Wang
- Department of liver disease, General Hospital of Beijing Military Region, Beijing 100700, China
| | - Kai Zhang
- Institute of Infectious Diseases/Research Center for Clinical and Translational Medicine, Beijing 302 Hospital, Beijing 100039, China
| | - Jin Li
- Institute of Infectious Diseases/Research Center for Clinical and Translational Medicine, Beijing 302 Hospital, Beijing 100039, China
| | - Juqiang Han
- Department of liver disease, General Hospital of Beijing Military Region, Beijing 100700, China
- * E-mail: (DX); (JH)
| | - Dongping Xu
- Institute of Infectious Diseases/Research Center for Clinical and Translational Medicine, Beijing 302 Hospital, Beijing 100039, China
- * E-mail: (DX); (JH)
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27
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Zhu HL, Li X, Li J, Zhang ZH. Genetic variation of occult hepatitis B virus infection. World J Gastroenterol 2016; 22:3531-3546. [PMID: 27053845 PMCID: PMC4814639 DOI: 10.3748/wjg.v22.i13.3531] [Citation(s) in RCA: 52] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/29/2015] [Revised: 12/13/2015] [Accepted: 12/30/2015] [Indexed: 02/06/2023] Open
Abstract
Occult hepatitis B virus infection (OBI), characterized as the persistence of hepatitis B virus (HBV) surface antigen (HBsAg) seronegativity and low viral load in blood or liver, is a special form of HBV infection. OBI may be related mainly to mutations in the HBV genome, although the underlying mechanism of it remains to be clarified. Mutations especially within the immunodominant “α” determinant of S protein are “hot spots” that could contribute to the occurrence of OBI via affecting antigenicity and immunogenicity of HBsAg or replication and secretion of virion. Clinical reports account for a large proportion of previous studies on OBI, while functional analyses, especially those based on full-length HBV genome, are rare.
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Powell EA, Razeghi S, Zucker S, Blackard JT. Occult Hepatitis B Virus Infection in a Previously Vaccinated Injection Drug User. HEPATITIS MONTHLY 2016; 16:e34758. [PMID: 27148386 PMCID: PMC4851822 DOI: 10.5812/hepatmon.34758] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/16/2015] [Accepted: 12/13/2015] [Indexed: 12/11/2022]
Abstract
INTRODUCTION Occult hepatitis B virus (HBV) is defined by the presence of HBV DNA in patient sera in the absence of HBsAg. Occult HBV has been associated with hepatocellular carcinoma, reactivation during immune suppression, and transmission to others. While the hepatitis B vaccine is very effective at preventing chronic HBV infection, recent studies indicate it is less effective at preventing occult HBV following infant vaccination. No studies, however, have examined the efficacy of adult HBV vaccination at preventing occult HBV. Here, we present the first report of occult HBV following adult vaccination. CASE PRESENTATION A 21-year old Caucasian female presented with tricuspid valve endocarditis secondary to methicillin-susceptible Staphylococcus aureus with non-ischemic cardiomyopathy. She reported active use of intravenous drugs. Her liver enzymes were elevated (ALT = 1873 IU/mL; AST = 4518 IU/mL), and she was found to have HCV and occult HBV. HBV viral loads ranged from 4608 - 8364 copies IU/mL during hospitalization. The patient's HBV was sequenced and found to be genotype D3 without any known diagnostic escape mutations. Immune complexes that may have prevented HBsAg detection were not observed. CONCLUSIONS HBV vaccination in infancy is effective at preventing chronic HBV infection but is less effective at preventing occult HBV infection. Similar studies examining the efficacy of adult HBV vaccination in preventing occult HBV have not been performed. This case highlights the importance of carefully determining the HBV status of high-risk individuals, as vaccination history and the presence of anti-HBs may not be adequate to rule out HBV infection, even in the absence of HBsAg.
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Affiliation(s)
- Eleanor A. Powell
- Division of Digestive Disease, Department of Internal Medicine, University of Cincinnati College of Medicine, Cincinnati, OH, USA
| | - Sanam Razeghi
- Division of Digestive Disease, Department of Internal Medicine, University of Cincinnati College of Medicine, Cincinnati, OH, USA
| | - Stephen Zucker
- Division of Digestive Disease, Department of Internal Medicine, University of Cincinnati College of Medicine, Cincinnati, OH, USA
| | - Jason T. Blackard
- Division of Digestive Disease, Department of Internal Medicine, University of Cincinnati College of Medicine, Cincinnati, OH, USA
- Corresponding Author: Jason T. Blackard, Division of Digestive Disease, Department of Internal Medicine, University of Cincinnati College of Medicine, Cincinnati, ML 0595, 231 Albert Sabin Way Cincinnati, OH 45267, USA. Tel: +1-513-558-4389, Fax: +1-513-558-1744, E-mail:
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29
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Zhang ZH, Wu CC, Chen XW, Li X, Li J, Lu MJ. Genetic variation of hepatitis B virus and its significance for pathogenesis. World J Gastroenterol 2016; 22:126-144. [PMID: 26755865 PMCID: PMC4698480 DOI: 10.3748/wjg.v22.i1.126] [Citation(s) in RCA: 65] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/27/2015] [Accepted: 11/13/2015] [Indexed: 02/06/2023] Open
Abstract
Hepatitis B virus (HBV) has a worldwide distribution and is endemic in many populations. Due to its unique life cycle which requires an error-prone reverse transcriptase for replication, it constantly evolves, resulting in tremendous genetic variation in the form of genotypes, sub-genotypes, and mutations. In recent years, there has been considerable research on the relationship between HBV genetic variation and HBV-related pathogenesis, which has profound implications in the natural history of HBV infection, viral detection, immune prevention, drug treatment and prognosis. In this review, we attempted to provide a brief account of the influence of HBV genotype on the pathogenesis of HBV infection and summarize our current knowledge on the effects of HBV mutations in different regions on HBV-associated pathogenesis, with an emphasis on mutations in the preS/S proteins in immune evasion, occult HBV infection and hepatocellular carcinoma (HCC), mutations in polymerase in relation to drug resistance, mutations in HBV core and e antigen in immune evasion, chronicalization of infection and hepatitis B-related acute-on-chronic liver failure, and finally mutations in HBV x proteins in HCC.
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30
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Koumbi L, Karayiannis P. The Epigenetic Control of Hepatitis B Virus Modulates the Outcome of Infection. Front Microbiol 2016; 6:1491. [PMID: 26779147 PMCID: PMC4701982 DOI: 10.3389/fmicb.2015.01491] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2015] [Accepted: 12/10/2015] [Indexed: 12/14/2022] Open
Abstract
Epigenetic modifications are stable alterations in gene expression that do not involve mutations of the genetic sequence itself. It has become increasingly clear that epigenetic factors contribute to the outcome of chronic hepatitis B virus (HBV) infection by affecting cellular and virion gene expression, viral replication and the development of hepatocellular carcinoma. HBV persists in the nucleus of infected hepatocytes as a stable non-integrated covalently closed circular DNA (cccDNA) which functions as a minichromosome. There are two major forms of HBV epigenetic regulation: posttranslational modification of histone proteins associated with the cccDNA minichromosome and DNA methylation of viral and host genomes. This review explores how HBV can interphase with host epigenetic regulation in order to evade host defences and to promote its own survival and persistence. We focus on the effect of cccDNA bound-histone modifications and the methylation status of HBV DNA in regulating viral replication. Investigation of HBV epigenetic control has important clinical correlates with regards to the development of potential therapeutic regimens that will successfully eradicate HBV infection and deal with HBV reactivation in those undergoing treatment with demethylating agents.
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Affiliation(s)
- Lemonica Koumbi
- Hepatology and Gastroenterology Section, Department of Medicine, Imperial College London, UK
| | - Peter Karayiannis
- Microbiology/Molecular Virology, University of Nicosia Medical School Nicosia, Cyprus
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31
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32
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Niller HH, Ay E, Banati F, Demcsák A, Takacs M, Minarovits J. Wild type HBx and truncated HBx: Pleiotropic regulators driving sequential genetic and epigenetic steps of hepatocarcinogenesis and progression of HBV-associated neoplasms. Rev Med Virol 2015; 26:57-73. [PMID: 26593760 DOI: 10.1002/rmv.1864] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2015] [Revised: 09/30/2015] [Accepted: 10/15/2015] [Indexed: 12/23/2022]
Abstract
Hepatitis B virus (HBV) is one of the causative agents of hepatocellular carcinoma. The molecular mechanisms of tumorigenesis are complex. One of the host factors involved is apparently the long-lasting inflammatory reaction which accompanies chronic HBV infection. Although HBV lacks a typical viral oncogene, the HBx gene encoding a pleiotropic regulatory protein emerged as a major player in liver carcinogenesis. Here we review the tumorigenic functions of HBx with an emphasis on wild type and truncated HBx variants, and their role in the transcriptional dysregulation and epigenetic reprogramming of the host cell genome. We suggest that HBx acquired by the HBV genome during evolution acts like a cellular proto-onc gene that is activated by deletion during hepatocarcinogenesis. The resulting viral oncogene (v-onc gene) codes for a truncated HBx protein that facilitates tumor progression. Copyright © 2015 John Wiley & Sons, Ltd.
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Affiliation(s)
- Hans Helmut Niller
- Institute for Medical Microbiology and Hygiene, University of Regensburg, Regensburg, Germany
| | - Eva Ay
- Department of Retrovirology, National Center for Epidemiology, Budapest, Hungary
| | - Ferenc Banati
- RT-Europe Nonprofit Research Center, Mosonmagyarovar, Hungary
| | - Anett Demcsák
- University of Szeged, Faculty of Dentistry, Department of Oral Biology and Experimental Dental Research, Szeged, Hungary
| | - Maria Takacs
- Division of Virology, National Center for Epidemiology, Budapest, Hungary
| | - Janos Minarovits
- University of Szeged, Faculty of Dentistry, Department of Oral Biology and Experimental Dental Research, Szeged, Hungary
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33
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Chen J, Wu M, Liu K, Zhang W, Li Y, Zhou X, Bai L, Yuan Z. New insights into hepatitis B virus biology and implications for novel antiviral strategies. Natl Sci Rev 2015. [DOI: 10.1093/nsr/nwv044] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
Abstract
Hepatitis B virus (HBV), a small DNA virus with a unique replication mode, can cause chronic hepatitis (CHB), which is characterized by the persistence of the viral covalently closed circular DNA that serves as the template for HBV replication and the production of large amounts of secreted HBV surface antigen (HBsAg) that is present in excess of the levels of infectious virus. Despite the success of currently approved antiviral treatments for CHB patients, including interferon and nucleotide analogs, which suppress HBV replication and reduce the risk of CHB-related liver diseases, these therapies fail to eradicate the virus in most of the patients. With the development of the cell and animal models for HBV study, a better understanding of the HBV life cycle has been achieved and a series of novel antiviral strategies that target different stages of HBV replication have been designed to overcome the viral factors that contribute to HBV persistence. Such basic HBV research advancements and therapeutic developments are the subject of this review.
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Affiliation(s)
- Jieliang Chen
- Key Laboratory of Medical Molecular Virology, Ministry of Education and Health, and Department of Medical Microbiology, School of Basic Medical Sciences, Shanghai Medical College, Fudan University, Shanghai 200032, China
- Research Unit, Shanghai Public Health Clinical Center, Fudan University, Shanghai 201508, China
| | - Min Wu
- Research Unit, Shanghai Public Health Clinical Center, Fudan University, Shanghai 201508, China
| | - Kuancheng Liu
- Key Laboratory of Medical Molecular Virology, Ministry of Education and Health, and Department of Medical Microbiology, School of Basic Medical Sciences, Shanghai Medical College, Fudan University, Shanghai 200032, China
- Institutes of Medical Microbiology and Biomedical Sciences, Fudan University, Shanghai 200032, China
| | - Wen Zhang
- Key Laboratory of Medical Molecular Virology, Ministry of Education and Health, and Department of Medical Microbiology, School of Basic Medical Sciences, Shanghai Medical College, Fudan University, Shanghai 200032, China
- Research Unit, Shanghai Public Health Clinical Center, Fudan University, Shanghai 201508, China
| | - Yaming Li
- Key Laboratory of Medical Molecular Virology, Ministry of Education and Health, and Department of Medical Microbiology, School of Basic Medical Sciences, Shanghai Medical College, Fudan University, Shanghai 200032, China
| | - Xiaohui Zhou
- Research Unit, Shanghai Public Health Clinical Center, Fudan University, Shanghai 201508, China
| | - Lu Bai
- Key Laboratory of Medical Molecular Virology, Ministry of Education and Health, and Department of Medical Microbiology, School of Basic Medical Sciences, Shanghai Medical College, Fudan University, Shanghai 200032, China
| | - Zhenghong Yuan
- Key Laboratory of Medical Molecular Virology, Ministry of Education and Health, and Department of Medical Microbiology, School of Basic Medical Sciences, Shanghai Medical College, Fudan University, Shanghai 200032, China
- Institutes of Medical Microbiology and Biomedical Sciences, Fudan University, Shanghai 200032, China
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34
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Pondé RAA. Molecular mechanisms underlying HBsAg negativity in occult HBV infection. Eur J Clin Microbiol Infect Dis 2015; 34:1709-31. [PMID: 26105620 DOI: 10.1007/s10096-015-2422-x] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2015] [Accepted: 06/03/2015] [Indexed: 02/06/2023]
Abstract
Although genomic detection is considered the gold standard test on HBV infection identification, the HBsAg investigation is still the most frequent clinical laboratory request to diagnose HBV infection in activity. However, the non-detection of HBsAg in the bloodstream of chronic or acutely infected individuals has been a phenomenon often observed in clinical practice, despite the high sensitivity and specificity of screening assays standardized commercially and adopted in routine. The expansion of knowledge about the hepatitis B virus biology (replication/life cycle, genetic variability/mutability/heterogeneity), their biochemical and immunological properties (antigenicity and immunogenicity), in turn, has allowed to elucidate some mechanisms that may explain the occurrence of this phenomenon. Therefore, the negativity for HBsAg during the acute or chronic infection course may become a fragile or at least questionable result. This manuscript discusses some mechanisms that could explain the negativity for HBsAg in a serological profile of individuals with HBV infection in activity, or factors that could compromise its detection in the bloodstream during HBV infection.
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Affiliation(s)
- R A A Pondé
- Laboratory of Human Virology, Institute of Tropical Pathology and Public Health, Federal University of Goiás, Goiânia, Goiás, Brazil,
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35
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Hou Z, Huang J, Zhong C, Li L, Xie Q, Ma M, Han T, Wang D, Maldonado M, Xu L, Huang T, Zhong Y. CpG islands of hepatitis B virus genome isolated from Chinese patients. Gene 2015; 561:261-7. [PMID: 25688883 DOI: 10.1016/j.gene.2015.02.036] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2014] [Revised: 01/22/2015] [Accepted: 02/13/2015] [Indexed: 02/05/2023]
Abstract
There are differences in the distribution and length of HBV CpG islands and the viral mutations contribute greatly to the development of HBV-related diseases. However, little is known regarding the effects of such difference and mutations in HBV genotypes B and C sequences on the regulation of HBV gene expression and their clinical outcomes. To study the distribution, length and genetic trait of CpG islands in normal and mutant sequences of HBV genotypes B and C, 320 HBV isolates from Chinese patients were retrieved from GenBank. Programs CLUSTALX 1.83 and MethPrimer were employed to perform multiple sequence alignments and to predict CpG islands, respectively. 72.0% genotype B isolates contained three conventional CpG islands, and 76.1% genotype C only contained CpG islands II and III. 14.6% genotype B and 7.5% genotype C contained three novel CpG islands. In genotype B, lengths of conventional CpG islands between normal and mutant isolates exhibited substantial variations, but in genotype C, those were relatively stable. CpG island II could be "truncated" or "split". "Truncated" region mutations were associated with structural and functional abnormalities of HBV genes. Rate of "split" CpG island II in genotype B was much higher than that in genotype C. In the majority of isolates from HCC and HBV-ACLF, genotype C lacked CpG island I and novel islands. Distribution, length and genetic trait of CpG islands in HBV genotypes B and C might affect their methylation status, and further affect regulation of HBV gene expression, leading to different clinical outcomes.
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Affiliation(s)
- Zhiwei Hou
- Guangdong Provincial Key Laboratory of Infectious Diseases and Molecular Immunopathology, Research Center for Reproductive Medicine, Shantou University Medical College, Shantou 515041, China
| | - Jihua Huang
- Jinxin Research Institute for Reproductive Medicine and Genetics, Chengdu Jinjiang Hospital for Maternal and Child Health Care, Chengdu 610000, China
| | - Chengyao Zhong
- Faculty of Science and Engineering, University Paul Sabatier, Toulouse 31062, France
| | - Lianbing Li
- Key Laboratory of Birth Defects and Reproductive Health of National Health and Family Planning Commission, Chongqing Population and Family Planning Science and Technology Research Institute, Chongqing 400020, China
| | - Qingdong Xie
- Guangdong Provincial Key Laboratory of Infectious Diseases and Molecular Immunopathology, Research Center for Reproductive Medicine, Shantou University Medical College, Shantou 515041, China
| | - Mingfu Ma
- Key Laboratory of Birth Defects and Reproductive Health of National Health and Family Planning Commission, Chongqing Population and Family Planning Science and Technology Research Institute, Chongqing 400020, China
| | - Tingting Han
- Jinxin Research Institute for Reproductive Medicine and Genetics, Chengdu Jinjiang Hospital for Maternal and Child Health Care, Chengdu 610000, China
| | - Degang Wang
- Guangdong Provincial Key Laboratory of Infectious Diseases and Molecular Immunopathology, Research Center for Reproductive Medicine, Shantou University Medical College, Shantou 515041, China
| | - Martin Maldonado
- Guangdong Provincial Key Laboratory of Infectious Diseases and Molecular Immunopathology, Research Center for Reproductive Medicine, Shantou University Medical College, Shantou 515041, China
| | - Lan Xu
- Guangdong Provincial Key Laboratory of Infectious Diseases and Molecular Immunopathology, Research Center for Reproductive Medicine, Shantou University Medical College, Shantou 515041, China
| | - Tianhua Huang
- Guangdong Provincial Key Laboratory of Infectious Diseases and Molecular Immunopathology, Research Center for Reproductive Medicine, Shantou University Medical College, Shantou 515041, China.
| | - Ying Zhong
- Jinxin Research Institute for Reproductive Medicine and Genetics, Chengdu Jinjiang Hospital for Maternal and Child Health Care, Chengdu 610000, China.
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36
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Darmawan E, Turyadi, El-Khobar KE, Nursanty NKD, Thedja MD, Muljono DH. Seroepidemiology and occult hepatitis B virus infection in young adults in Banjarmasin, Indonesia. J Med Virol 2014; 87:199-207. [PMID: 25521058 DOI: 10.1002/jmv.24045] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 07/11/2014] [Indexed: 02/06/2023]
Abstract
Hepatitis B virus (HBV) infection remains a public health problem in Indonesia. There has been limited data regarding HBV infection in young adult population. This study aimed to evaluate the seroepidemiology of HBV infection and characterize occult HBV variants in healthy young adults in Banjarmasin, Indonesia, who were born before the implementation of the universal infant hepatitis B vaccination. Serum samples of 195 healthy young adults were tested for HBsAg, anti-HBc, and anti-HBs. The prevalence of HBsAg, anti-HBc, and anti-HBs was 9 (4.6%), 62 (31.8%), and 96 (49.2%), respectively. Seventy four (37.9%) samples were seronegative for all three parameters, indicating the susceptibility to HBV infection. Among 66 samples positive for HBsAg and/or anti-HBc, 13 (19.7%) were HBV DNA positive; of these, four were HBsAg positive and nine were HBsAg negative, and categorized as occult HBV infection. Most occult HBV cases had high-level anti-HBs (>100 IU/l), suggesting that blood with positive anti-HBs and anti-HBc could not be regarded as noninfectious. Thirteen amino acid substitutions were identified: T126S, P127S, Q129R, T131N, M133T, and Y161S in the HBsAg-positive group; P120T, T126I, G145S, Y161F, E164V, and V168F in the occult-HBV group; and T143S in both groups. More studies are required to provide data on the prevalence and characteristics of mutants to ensure reliable diagnosis. The occult HBV infection, combined with the HBsAg prevalence, could indicate the high HBV carriage among young adults in this area. The high percentage of individuals susceptible to HBV infection reiterates the need for catch-up immunization strategies targeted at young adults.
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Affiliation(s)
- Erica Darmawan
- Eijkman Institute for Molecular Biology, Jakarta, Indonesia
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37
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Ferrari TCA, Xavier MAP, Vidigal PVT, Amaral NS, Diniz PA, Resende AP, Miranda DM, Faria AC, Lima AS, Faria LC. Occult hepatitis B virus infection in liver transplant patients in a Brazilian referral center. ACTA ACUST UNITED AC 2014. [PMID: 25296362 PMCID: PMC4230290 DOI: 10.1590/1414-431x20143782] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Estimates of occult hepatitis B virus (HBV) infection prevalence varies among different studies depending on the prevalence of HBV infection in the study population and on the sensitivity of the assay used to detect HBV DNA. We investigated the prevalence of occult HBV infection in cirrhotic patients undergoing liver transplantation in a Brazilian referral center. Frozen liver samples from 68 adults were analyzed using a nested polymerase chain reaction assay for HBV DNA. The specificity of the amplified HBV sequences was confirmed by direct sequencing of the amplicons. The patient population comprised 49 (72.1%) males and 19 (27.9%) females with a median age of 53 years (range=18-67 years). Occult HBV infection was diagnosed in three (4.4%) patients. The etiologies of the underlying chronic liver disease in these cases were alcohol abuse, HBV infection, and cryptogenic cirrhosis. Two of the patients with cryptic HBV infection also presented hepatocellular carcinoma. Markers of previous HBV infection were available in two patients with occult HBV infection and were negative in both. In conclusion, using a sensitive nested polymerase chain reaction assay to detect HBV DNA in frozen liver tissue, we found a low prevalence of occult HBV infection in cirrhotic patients undergoing liver transplant, probably due to the low prevalence of HBV infection in our population.
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Affiliation(s)
- T C A Ferrari
- Departamento de Clínica Médica, Faculdade de Medicina, Universidade Federal de Minas Gerais, Belo Horizonte, MG, Brasil
| | - M A P Xavier
- Departamento de Anatomia Patológica e Medicina Legal, Faculdade de Medicina, Universidade Federal de Minas Gerais, Belo Horizonte, MG, Brasil
| | - P V T Vidigal
- Departamento de Anatomia Patológica e Medicina Legal, Faculdade de Medicina, Universidade Federal de Minas Gerais, Belo Horizonte, MG, Brasil
| | - N S Amaral
- Laboratório de Genética Molecular, Faculdade de Medicina, Universidade Federal de Minas Gerais, Belo Horizonte, MG, Brasil
| | - P A Diniz
- Departamento de Clínica Médica, Faculdade de Medicina, Universidade Federal de Minas Gerais, Belo Horizonte, MG, Brasil
| | - A P Resende
- Instituto Alfa de Gastroenterologia, Hospital das Clínicas, Universidade Federal de Minas Gerais, Belo Horizonte, MG, Brasil
| | - D M Miranda
- Departamento de Pediatria, Faculdade de Medicina, Universidade Federal de Minas Gerais, Belo Horizonte, MG, Brasil
| | - A C Faria
- Departamento de Clínica Médica, Faculdade de Medicina, Universidade Federal de Minas Gerais, Belo Horizonte, MG, Brasil
| | - A S Lima
- Instituto Alfa de Gastroenterologia, Hospital das Clínicas, Universidade Federal de Minas Gerais, Belo Horizonte, MG, Brasil
| | - L C Faria
- Departamento de Clínica Médica, Faculdade de Medicina, Universidade Federal de Minas Gerais, Belo Horizonte, MG, Brasil
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38
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Powell EA, Gededzha MP, Rentz M, Rakgole NJ, Selabe SG, Seleise TA, Mphahlele MJ, Blackard JT. Mutations associated with occult hepatitis B in HIV-positive South Africans. J Med Virol 2014; 87:388-400. [PMID: 25164924 DOI: 10.1002/jmv.24057] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 07/27/2014] [Indexed: 12/16/2022]
Abstract
Occult hepatitis B is characterized by the absence of hepatitis B surface antigen (HBsAg) but the presence of HBV DNA. Because diagnosis of hepatitis B virus (HBV) typically includes HBsAg detection, occult HBV remains largely undiagnosed. Occult HBV is associated with increased risk of hepatocellular carcinoma, reactivation to chronic HBV during immune suppression, and transmission during blood transfusion and liver transplant. The mechanisms leading to occult HBV infection are unclear, although viral mutations are likely a significant factor. In this study, sera from 394 HIV-positive South Africans were tested for HBV DNA and HBsAg. For patients with detectable HBV DNA, the overlapping surface and polymerase open reading frames (ORFs) were sequenced. Occult-associated mutations-those mutations found exclusively in individuals with occult HBV infection but not in individuals with chronic HBV infection from the same cohort or GenBank references-were identified. Ninety patients (22.8%) had detectable HBV DNA. Of these, 37 had detectable HBsAg, while 53 lacked detectable surface antigen. The surface and polymerase ORFs were cloned successfully for 19 patients with chronic HBV and 30 patients with occult HBV. In total, 235 occult-associated mutations were identified. Ten occult-associated mutations were identified in more than one patient. Additionally, 15 amino acid positions had two distinct occult-associated mutations at the same residue. Occult-associated mutations were common and present in all regions of the surface and polymerase ORFs. Further study is underway to determine the effects of these mutations on viral replication and surface antigen expression in vitro.
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Affiliation(s)
- Eleanor A Powell
- Division of Digestive Disease, University of Cincinnati College of Medicine, Cincinnati, Ohio
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39
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Abstract
DNA methylation plays an important role in disease development, cell differentiation, embryonic development, and environmental adaptation by regulating gene transcription, gene imprinting and X chromosome inactivation and defending from invasion of exogenous genetic material. DNA methylation is a hot topic in the study of epigenetics. Numerous studies have demonstrated that DNA methylation plays an important role in the occurrence and development of liver diseases, and it influences the process of liver diseases through regulation of the activation and expression of genes related to lipid metabolism, inflammation, and cell proliferation in liver cells. In this review, we will review the recent progress in understanding the role and mechanisms of DNA methylation in alcoholic liver disease, nonalcoholic fatty liver disease, viral hepatitis, liver fibrosis and hepatocellular carcinoma, with an aim to provide a theoretical basis for the treatment of liver diseases and drug development.
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Chamni N, Louisirirotchanakul S, Oota S, Sakuldamrongpanish T, Saldanha J, Chongkolwatana V, Phikulsod S. Genetic characterization and genotyping of hepatitis B virus (HBV) isolates from donors with an occult HBV infection. Vox Sang 2014; 107:324-32. [PMID: 25040474 DOI: 10.1111/vox.12178] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2014] [Revised: 05/29/2014] [Accepted: 06/12/2014] [Indexed: 12/20/2022]
Abstract
BACKGROUND AND OBJECTIVES Screening of Thai blood donors has resulted in the detection of donors with an occult HBV infection (OBI), where HBsAg is undetectable, but hepatitis B virus (HBV) DNA is present in serum in low concentrations. This study was designed to determine whether the occurrence of OBI in donors was linked to the HBV genotype and possibly to mutations in the surface (S) and core (C) gene regions. MATERIALS AND METHODS Mutations in the S and C gene regions in 48 Thai donors with OBI were mapped by sequencing. Genotyping was determined with the INNO-LiPA test and by phylogenetic analysis of sequences from the S and C genes. RESULTS The majority of OBI samples were genotype C (81·3%) with 6·3% of samples being genotype B. In addition, two genotype I isolates were identified. Mutations in the S region (100%) were found especially in loop 1 of the major hydrophilic loop (MHL) at positions I110L, T114S, T126I and S113T, whereas mutations in the C region (65%) were within the basal core promoter region (position A1762T/G1764A) and precore region (position G1896A). CONCLUSION The majority of OBI samples were HBV genotype C, although genotype I, which is newly emerging in Thailand, was also detected. The study demonstrated that OBI was probably not associated with a particular HBV genotype or with certain mutations in the S and C gene regions. However, mutations in the C gene region which could potentially impair viral replication and HBsAg production and potentially lead to OBI were identified.
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Affiliation(s)
- N Chamni
- Department of Microbiology, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok, Thailand
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Cheng HR, Kao JH, Wu HL, Chen TC, Tseng TC, Liu CH, Su TH, Chen PJ, Chen DS, Liu CJ. Clinical and virological features of occult hepatitis B in patients with HBsAg seroclearance post-treatment or spontaneously. Liver Int 2014; 34:e71-9. [PMID: 24119014 DOI: 10.1111/liv.12324] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/09/2013] [Accepted: 08/29/2013] [Indexed: 12/16/2022]
Abstract
BACKGROUND Occult hepatitis B virus (HBV) infection (OHB) may exist in patients experiencing hepatitis B surface antigen (HBsAg) seroclearance. AIMS We examined the clinical and virological features of OHB in patients who lost HBsAg post-treatment or spontaneously. METHODS We collected 44 patients with HBsAg seroclearance: 15 patients with dual HBV/hepatitis C virus (HCV) infection who lost HBsAg after peginterferon alfa-2a (PEG-IFN) plus ribavirin therapy; 13 HBV mono-infected patients who lost HBsAg after various oral antiviral therapies; and 16 patients who lost HBsAg spontaneously. OHB was defined as detectable serum HBV DNA in the absence of HBsAg. Viral mutations associated with OHB were identified by comparison with matched controls that remained positive for HBsAg, and further characterized in vitro. RESULTS The prevalence of OHB was 34.1% (15/44) in all patients, which was not significantly different among three groups. One mutation in surface promoter/polymerase region, C3050T (preS1T68I), was identified to be associated with the seroclearance of HBsAg in six cases. This mutation does not change the amino acid sequence of the polymerase protein. The S promoter activity was significantly lower in the construct containing C3050T mutation as compared with the wild-type (P = 0.0008). However, this mutation did not affect HBV replication, transcription and translation in the context of the full-length HBV genome. OHB was not rare in patients with HBsAg seroclearance. CONCLUSIONS One mutation, C3050T (preS1T68I), decreased S promoter activity; nevertheless, other factors may play more important role in the clearance of HBsAg in these OHB patients.
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Affiliation(s)
- Huei-Ru Cheng
- Graduate Institute of Clinical Medicine, National Taiwan University College of Medicine, Taipei, Taiwan
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42
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Huang FY, Wong DKH, Seto WK, Zhang AY, Lee CK, Lin CK, Fung J, Lai CL, Yuen MF. Sequence variations of full-length hepatitis B virus genomes in Chinese patients with HBsAg-negative hepatitis B infection. PLoS One 2014; 9:e99028. [PMID: 24901840 PMCID: PMC4047052 DOI: 10.1371/journal.pone.0099028] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2014] [Accepted: 05/09/2014] [Indexed: 12/16/2022] Open
Abstract
BACKGROUND The underlying mechanism of HBsAg-negative hepatitis B virus (HBV) infection is notoriously difficult to elucidate because of the extremely low DNA levels which define the condition. We used a highly efficient amplification method to overcome this obstacle and achieved our aim which was to identify specific mutations or sequence variations associated with this entity. METHODS A total of 185 sera and 60 liver biopsies from HBsAg-negative, HBV DNA-positive subjects or known chronic hepatitis B (CHB) subjects with HBsAg seroclearance were amplified by rolling circle amplification followed by full-length HBV genome sequencing. Eleven HBsAg-positive CHB subjects were included as controls. The effects of pivotal mutations identified on regulatory regions on promoter activities were analyzed. RESULTS 22 and 11 full-length HBV genomes were amplified from HBsAg-negative and control subjects respectively. HBV genotype C was the dominant strain. A higher mutation frequency was observed in HBsAg-negative subjects than controls, irrespective of genotype. The nucleotide diversity over the entire HBV genome was significantly higher in HBsAg-negative subjects compared with controls (p = 0.008) and compared with 49 reference sequences from CHB patients (p = 0.025). In addition, HBsAg-negative subjects had significantly higher amino acid substitutions in the four viral genes than controls (all p<0.001). Many mutations were uniquely found in HBsAg-negative subjects, including deletions in promoter regions (13.6%), abolishment of pre-S2/S start codon (18.2%), disruption of pre-S2/S mRNA splicing site (4.5%), nucleotide duplications (9.1%), and missense mutations in "α" determinant region, contributing to defects in HBsAg production. CONCLUSIONS These data suggest an accumulation of multiple mutations constraining viral transcriptional activities contribute to HBsAg-negativity in HBV infection.
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Affiliation(s)
- Fung-Yu Huang
- Department of Medicine, The University of Hong Kong, Queen Mary Hospital, Hong Kong, China
| | - Danny Ka-Ho Wong
- Department of Medicine, The University of Hong Kong, Queen Mary Hospital, Hong Kong, China
- State Key Laboratory for Liver Research, The University of Hong Kong, Queen Mary Hospital, Hong Kong, China
| | - Wai-Kay Seto
- Department of Medicine, The University of Hong Kong, Queen Mary Hospital, Hong Kong, China
| | - An-Ye Zhang
- Department of Medicine, The University of Hong Kong, Queen Mary Hospital, Hong Kong, China
| | - Cheuk-Kwong Lee
- Hong Kong Red Cross Blood Transfusion Service, Hospital Authority, Hong Kong, China
| | - Che-Kit Lin
- Hong Kong Red Cross Blood Transfusion Service, Hospital Authority, Hong Kong, China
| | - James Fung
- Department of Medicine, The University of Hong Kong, Queen Mary Hospital, Hong Kong, China
- State Key Laboratory for Liver Research, The University of Hong Kong, Queen Mary Hospital, Hong Kong, China
| | - Ching-Lung Lai
- Department of Medicine, The University of Hong Kong, Queen Mary Hospital, Hong Kong, China
- State Key Laboratory for Liver Research, The University of Hong Kong, Queen Mary Hospital, Hong Kong, China
| | - Man-Fung Yuen
- Department of Medicine, The University of Hong Kong, Queen Mary Hospital, Hong Kong, China
- State Key Laboratory for Liver Research, The University of Hong Kong, Queen Mary Hospital, Hong Kong, China
- * E-mail:
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Zhang X, Hou J, Lu M. Regulation of hepatitis B virus replication by epigenetic mechanisms and microRNAs. Front Genet 2013; 4:202. [PMID: 24133502 PMCID: PMC3796260 DOI: 10.3389/fgene.2013.00202] [Citation(s) in RCA: 59] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2013] [Accepted: 09/22/2013] [Indexed: 12/17/2022] Open
Abstract
The hepatitis B virus (HBV) genome forms a covalently closed circular DNA (cccDNA) minichromosome that persists in the nucleus of virus-infected hepatocytes. HBV cccDNA serves as the template for viral mRNA synthesis and is subject to epigenetic regulation by several mechanisms, including DNA methylation and histone acetylation. Recently, microRNAs (miRNAs), a class of small non-coding RNAs, were also directly connected to the epigenetic machinery through a regulatory loop. Epigenetic modifications have been shown to affect miRNA expression, and a sub-group of miRNAs (defined as epi-miRNAs) can directly target effectors of the epigenetic machinery. In this review, we will summarize recent findings on the epigenetic mechanisms controlling HBV cccDNA function, primarily focusing on the epi-miRNA functions operating in HBV replication. Investigation of the epigenetic regulation of HBV replication may help to discover novel potential therapeutic targets for drug development with the goal to eradicate the HBV cccDNA pool in hepatocytes.
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Affiliation(s)
- Xiaoyong Zhang
- Hepatology Unit and Department of Infectious Diseases, Nanfang Hospital, Southern Medical University Guangzhou, China ; Institute of Virology, University Hospital of Essen, University of Duisburg Essen Essen, Germany
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44
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Taha SE, El-Hady SA, Ahmed TM, Ahmed IZ. Detection of occult HBV infection by nested PCR assay among chronic hepatitis C patients with and without hepatocellular carcinoma. EGYPTIAN JOURNAL OF MEDICAL HUMAN GENETICS 2013. [DOI: 10.1016/j.ejmhg.2013.06.001] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
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45
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Zhang Y, Li C, Zhang Y, Zhu H, Kang Y, Liu H, Wang J, Qin Y, Mao R, Xie Y, Huang Y, Zhang J. Comparative analysis of CpG islands among HBV genotypes. PLoS One 2013; 8:e56711. [PMID: 23451072 PMCID: PMC3579858 DOI: 10.1371/journal.pone.0056711] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2012] [Accepted: 01/14/2013] [Indexed: 12/18/2022] Open
Abstract
DNA methylation is being increasingly recognized to play a role in regulation of hepatitis B virus (HBV) gene expression. The aim of this study was to compare the CpG island distribution among different HBV genotypes. We analyzed 176 full-length HBV genomic sequences obtained from the GenBank database, belonging to genotypes A through J, to identify the CpG islands in the HBV genomes. Our results showed that while 79 out of 176 sequences contained three conventional CpG islands (I–III) as previously described, 83 HBV sequences harbored only two of the three known islands. Novel CpG islands were identified in the remaining 14 HBV isolates and named as CpG island IV, V, and VI. Among the eight known HBV genotypes and two putative genotypes, while HBV genomes containing three CpG islands were predominant in genotypes A, B, D, E, and I; genotypes C, F, G, and H tended to contain only two CpG islands (II and III). In conclusion, the CpG islands, which are potential targets for DNA methylation mediated by the host functions, differ among HBV genotypes, and these genotype-specific differences in CpG island distribution could provide new insights into the understanding of epigenetic regulation of HBV gene expression and hepatitis B disease outcome.
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Affiliation(s)
- Yongmei Zhang
- Department of Infectious Diseases, Huashan Hospital, Shanghai Medical College, Fudan University, Shanghai, China
| | - Chenxiao Li
- Department of Basic Medical Sciences, Shanghai Medical College, Fudan University, Shanghai, China
| | - Yijun Zhang
- Department of Infectious Diseases, Huashan Hospital, Shanghai Medical College, Fudan University, Shanghai, China
| | - Haoxiang Zhu
- Department of Infectious Diseases, Huashan Hospital, Shanghai Medical College, Fudan University, Shanghai, China
| | - Yaoyue Kang
- Department of Infectious Diseases, Huashan Hospital, Shanghai Medical College, Fudan University, Shanghai, China
| | - Hongyan Liu
- Department of Infectious Diseases, Huashan Hospital, Shanghai Medical College, Fudan University, Shanghai, China
| | - Jinyu Wang
- Department of Infectious Diseases, Huashan Hospital, Shanghai Medical College, Fudan University, Shanghai, China
| | - Yanli Qin
- Department of Infectious Diseases, Huashan Hospital, Shanghai Medical College, Fudan University, Shanghai, China
| | - Richeng Mao
- Department of Infectious Diseases, Huashan Hospital, Shanghai Medical College, Fudan University, Shanghai, China
| | - Yi Xie
- Department of Infectious Diseases, Huashan Hospital, Shanghai Medical College, Fudan University, Shanghai, China
| | - Yuxian Huang
- Department of Infectious Diseases, Huashan Hospital, Shanghai Medical College, Fudan University, Shanghai, China
- * E-mail: (JZ) (YH); (YH) (JZ)
| | - Jiming Zhang
- Department of Infectious Diseases, Huashan Hospital, Shanghai Medical College, Fudan University, Shanghai, China
- Key Laboratory of Medical Molecular Virology (MOH & MOE), Shanghai Medical College, Fudan University, Shanghai, China
- * E-mail: (JZ) (YH); (YH) (JZ)
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Abstract
The long-lasting persistence of hepatitis B virus (HBV) genomes in the liver (with detectable or undetectable HBV DNA in the serum) of individuals testing negative for the HBV surface antigen (HBsAg) is termed occult HBV infection (OBI). Although in a minority of cases the lack of HBsAg detection is due to infection with variant viruses unrecognized by available assays (S-escape mutants), the typical OBI is related to replication-competent HBVs strongly suppressed in their replication activity. The causes of HBV suppression are not yet well clarified, although the host's immune surveillance and epigenetic mechanisms are likely involved. OBI is a worldwide diffused entity, but the available data of prevalence in various categories of individuals are often contrasting because of the different sensitivity and specificity of the methods used for its detection in many studies. OBI may have an impact in several different clinical contexts. In fact, it can be transmitted (i.e., through blood transfusion and liver transplantation) causing classic forms of hepatitis B in newly infected individuals. The development of an immunosuppressive status (mainly by immunotherapy or chemotherapy) may induce OBI reactivation and development of acute and often severe hepatitis. Finally, evidence suggests that OBI can favor the progression of liver fibrosis, in particular in HCV-infected patients. The possible contribution of OBI to the establishment of cirrhosis also implies its possible indirect role in the development of hepatocellular carcinoma. On the other hand, OBI may maintain most of the direct transforming properties of the overt HBV infection, such as the capacity to integrate in the host's genome and to synthesize pro-oncogenic proteins.
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47
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Abstract
Chronic hepatitis B virus (HBV) infection is a complex clinical entity frequently associated with cirrhosis and hepatocellular carcinoma (HCC). The persistence of HBV genomes in the absence of detectable surface antigenemia is termed occult HBV infection. Mutations in the surface gene rendering HBsAg undetectable by commercial assays and inhibition of HBV by suppression of viral replication and viral proteins represent two fundamentally different mechanisms that lead to occult HBV infections. The molecular mechanisms underlying occult HBV infections, including recently identified mechanisms associated with the suppression of HBV replication and inhibition of HBV proteins, are reviewed in detail. The availability of highly sensitive molecular methods has led to increased detection of occult HBV infections in various clinical settings. The clinical relevance of occult HBV infection and the utility of appropriate diagnostic methods to detect occult HBV infection are discussed. The need for specific guidelines on the diagnosis and management of occult HBV infection is being increasingly recognized; the aspects of mechanistic studies that warrant further investigation are discussed in the final section.
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Abstract
Chronic hepatitis B virus (HBV) infection is a complex clinical entity frequently associated with cirrhosis and hepatocellular carcinoma (HCC). The persistence of HBV genomes in the absence of detectable surface antigenemia is termed occult HBV infection. Mutations in the surface gene rendering HBsAg undetectable by commercial assays and inhibition of HBV by suppression of viral replication and viral proteins represent two fundamentally different mechanisms that lead to occult HBV infections. The molecular mechanisms underlying occult HBV infections, including recently identified mechanisms associated with the suppression of HBV replication and inhibition of HBV proteins, are reviewed in detail. The availability of highly sensitive molecular methods has led to increased detection of occult HBV infections in various clinical settings. The clinical relevance of occult HBV infection and the utility of appropriate diagnostic methods to detect occult HBV infection are discussed. The need for specific guidelines on the diagnosis and management of occult HBV infection is being increasingly recognized; the aspects of mechanistic studies that warrant further investigation are discussed in the final section.
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49
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Svicher V, Cento V, Bernassola M, Neumann-Fraune M, Hemert FV, Chen M, Salpini R, Liu C, Longo R, Visca M, Romano S, Micheli V, Bertoli A, Gori C, Ceccherini-Silberstein F, Sarrecchia C, Andreoni M, Angelico M, Ursitti A, Spanò A, Zhang JM, Verheyen J, Cappiello G, Perno CF. Novel HBsAg markers tightly correlate with occult HBV infection and strongly affect HBsAg detection. Antiviral Res 2012; 93:86-93. [DOI: 10.1016/j.antiviral.2011.10.022] [Citation(s) in RCA: 59] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2011] [Revised: 10/26/2011] [Accepted: 10/30/2011] [Indexed: 02/06/2023]
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50
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