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Journal of Hepatology Sep 2023
Topics: Hepatitis B virus; Hepatitis B Core Antigens; DNA, Viral; Hepatitis B e Antigens
PubMed: 36965779
DOI: 10.1016/j.jhep.2023.03.008 -
Viruses Mar 2017Hepatitis B virus (HBV) is a para-retrovirus or retroid virus that contains a double-stranded DNA genome and replicates this DNA via reverse transcription of a RNA... (Review)
Review
Hepatitis B virus (HBV) is a para-retrovirus or retroid virus that contains a double-stranded DNA genome and replicates this DNA via reverse transcription of a RNA pregenome. Viral reverse transcription takes place within a capsid upon packaging of the RNA and the viral reverse transcriptase. A major characteristic of HBV replication is the selection of capsids containing the double-stranded DNA, but not those containing the RNA or the single-stranded DNA replication intermediate, for envelopment during virion secretion. The complete HBV virion particles thus contain an outer envelope, studded with viral envelope proteins, that encloses the capsid, which, in turn, encapsidates the double-stranded DNA genome. Furthermore, HBV morphogenesis is characterized by the release of subviral particles that are several orders of magnitude more abundant than the complete virions. One class of subviral particles are the classical surface antigen particles (Australian antigen) that contain only the viral envelope proteins, whereas the more recently discovered genome-free (empty) virions contain both the envelope and capsid but no genome. In addition, recent evidence suggests that low levels of RNA-containing particles may be released, after all. We will summarize what is currently known about how the complete and incomplete HBV particles are assembled. We will discuss briefly the functions of the subviral particles, which remain largely unknown. Finally, we will explore the utility of the subviral particles, particularly, the potential of empty virions and putative RNA virions as diagnostic markers and the potential of empty virons as a vaccine candidate.
Topics: Hepatitis B virus; Humans; Virion; Virus Assembly; Virus Replication
PubMed: 28335554
DOI: 10.3390/v9030056 -
Reviews in Medical Virology Sep 2016Chronic HBV infection affects more than 240 million people worldwide and is associated with a broad range of clinical manifestations including liver cirrhosis, liver... (Review)
Review
Chronic HBV infection affects more than 240 million people worldwide and is associated with a broad range of clinical manifestations including liver cirrhosis, liver failure and hepatocellular carcinoma. Because of the lack of an efficient cure for chronic hepatitis B, the main goal of antiviral therapy is the prevention of liver disease progression coupled with prolonged survival of patients. Because HBV viral load has been shown to be a crucial determinant of the progression of liver damage, these goals can be achieved as long as HBV replication can be suppressed. Unfortunately, long-term therapy with the low-to-moderate genetic barrier drugs, which are still recommended in a majority of developing countries, are strongly associated with HBV resistance development and treatment failure. In such cases, the precise and accurate determination of drug-resistant variants in an individual patient before treatment is important for a proper choice of first-line potent therapy. Nowadays, a number of techniques are available to study HBV quasispecies evolution. This review describes the advantages and limitations of various assays detecting drug-resistant HBV variants. Copyright © 2016 John Wiley & Sons, Ltd.
Topics: Antiviral Agents; Genetic Variation; Genotyping Techniques; Hepatitis B virus; Hepatitis B, Chronic; Humans; Mutation
PubMed: 27506508
DOI: 10.1002/rmv.1897 -
Cellular and Molecular Gastroenterology... 2022
Topics: Hepatitis B virus
PubMed: 35691338
DOI: 10.1016/j.jcmgh.2022.05.009 -
Clinical Gastroenterology and... Apr 2017
Topics: Antiviral Agents; Hepacivirus; Hepatitis; Hepatitis B virus; Hepatitis C; Humans
PubMed: 28025157
DOI: 10.1016/j.cgh.2016.12.016 -
Bacteriophages and their applications in the diagnosis and treatment of hepatitis B virus infection.World Journal of Gastroenterology Sep 2014Hepatitis B virus (HBV) infection is a major global health challenge leading to serious disorders such as cirrhosis and hepatocellular carcinoma. Currently, there exist... (Review)
Review
Hepatitis B virus (HBV) infection is a major global health challenge leading to serious disorders such as cirrhosis and hepatocellular carcinoma. Currently, there exist various diagnostic and therapeutic approaches for HBV infection. However, prevalence and hazardous effects of chronic viral infection heighten the need to develop novel methodologies for the detection and treatment of this infection. Bacteriophages, viruses that specifically infect bacterial cells, with a long-established tradition in molecular biology and biotechnology have recently been introduced as novel tools for the prevention, diagnosis and treatment of HBV infection. Bacteriophages, due to tremendous genetic flexibility, represent potential to undergo a huge variety of surface modifications. This property has been the rationale behind introduction of phage display concept. This powerful approach, together with combinatorial chemistry, has shaped the concept of phage display libraries with diverse applications for the detection and therapy of HBV infection. This review aims to offer an insightful overview of the potential of bacteriophages in the development of helpful prophylactic (vaccine design), diagnostic and therapeutic strategies for HBV infection thereby providing new perspectives to the growing field of bacteriophage researches directing towards HBV infection.
Topics: Animals; Antiviral Agents; Bacteriophages; Cell Surface Display Techniques; Drug Design; Gene Expression Regulation, Viral; Genotype; Hepatitis B; Hepatitis B Vaccines; Hepatitis B virus; Humans; Molecular Targeted Therapy; Predictive Value of Tests
PubMed: 25206272
DOI: 10.3748/wjg.v20.i33.11671 -
Medicine Dec 2021Hepatitis B virus (HBV) genotypes and subgenotypes have distinct geographical distributions and influence a number of clinical disease features and responses to... (Meta-Analysis)
Meta-Analysis
Hepatitis B virus (HBV) genotypes and subgenotypes have distinct geographical distributions and influence a number of clinical disease features and responses to treatment. There are many reports on the distribution of HBV genotypes, but great differences are present between studies. What's more, a meta-analysis of HBV genotype- and subgenotype-distribution by country is lacking.A comprehensive literature search was performed in PubMed and a systematic search of full-length HBV sequences and S gene sequences was conducted in the GenBank database. HBV genotypes were checked and subgenotypes were determined by phylogenetic comparison of full-length HBV sequences or S gene sequences. STATA 12.0 was used for the analysis for countries with multiple datasets. BEAST 2.5.2 was used for Bayesian phylogenetic analysis to infer the evolutionary time scales of HBV.This study includes 309 datasets from 110 countries, including 188 relevant studies, 58 full-length gene datasets, and 63 S gene datasets. The meta-analysis was performed on 274 datasets from 75 countries. The distribution of genotypes is more detailed than those described by previous studies. While the overall genotype distribution is similar to that reported in previous studies, some notable aspects were different. The main genotypes present in south-eastern Africa, North Africa, and West Africa are genotypes A, D, and E, respectively. Genotypes G and H are mainly distributed in Mexico. Genotype F is mainly distributed in central and South America, but genotypes A and D are also common in Brazil, Cuba, and Haiti.This study provides a more accurate description of the distribution of HBV genotypes and subgenotypes in different countries and suggests that the differences in genotype distribution may be related to ethnicity and human migration.
Topics: Bayes Theorem; DNA, Viral; Genotype; Hepatitis B; Hepatitis B virus; Humans; Phylogeny
PubMed: 34918643
DOI: 10.1097/MD.0000000000027941 -
Frontiers in Immunology 2022As a small DNA virus, hepatitis B virus (HBV) plays a pivotal role in the development of various liver diseases, including hepatitis, cirrhosis, and liver cancer. Among... (Review)
Review
As a small DNA virus, hepatitis B virus (HBV) plays a pivotal role in the development of various liver diseases, including hepatitis, cirrhosis, and liver cancer. Among the molecules encoded by this virus, the HBV X protein (HBX) is a viral transactivator that plays a vital role in HBV replication and virus-associated diseases. Accumulating evidence so far indicates that pattern recognition receptors (PRRs) are at the front-line of the host defense responses to restrict the virus by inducing the expression of interferons and various inflammatory factors. However, depending on HBX, the virus can control PRR signaling by modulating the expression and activity of essential molecules involved in the toll-like receptor (TLR), retinoic acid inducible gene I (RIG-I)-like receptor (RLR), and NOD-like receptor (NLR) signaling pathways, to not only facilitate HBV replication, but also promote the development of viral diseases. In this review, we provide an overview of the mechanisms that are linked to the regulation of PRR signaling mediated by HBX to inhibit innate immunity, regulation of viral propagation, virus-induced inflammation, and hepatocarcinogenesis. Given the importance of PRRs in the control of HBV replication, we propose that a comprehensive understanding of the modulation of cellular factors involved in PRR signaling induced by the viral protein may open new avenues for the treatment of HBV infection.
Topics: Hepatitis B; Hepatitis B virus; Humans; Immunity, Innate; Receptors, Pattern Recognition; Signal Transduction
PubMed: 35251017
DOI: 10.3389/fimmu.2022.829923 -
International Journal of Molecular... Mar 2024causes chronic hepatitis in a broad range of mammals, including primates, cats, woodchucks, and bats. Hepatitis B virus (HBV) X protein inhibits type-I interferon (IFN)...
causes chronic hepatitis in a broad range of mammals, including primates, cats, woodchucks, and bats. Hepatitis B virus (HBV) X protein inhibits type-I interferon (IFN) signaling, thereby promoting HBV escape from the human innate immune system and establishing persistent infection. However, whether X proteins of viruses in other species display a similar inhibitory activity remains unknown. Here, we investigated the anti-IFN activity of 17 X proteins derived from various hosts. We observed conserved activity of X proteins in inhibiting TIR-domain-containing adaptor protein inducing IFN-β (TRIF)-mediated IFN-β signaling pathway through TRIF degradation. X proteins from domestic cat hepadnavirus (DCH), a novel member of , inhibited mitochondrial antiviral signaling protein (MAVS)-mediated IFNβ signaling pathway comparable with HBV X. These results indicate that inhibition of IFN signaling is conserved in X proteins.
Topics: Humans; Animals; Cats; Orthohepadnavirus; Signal Transduction; Adaptor Proteins, Vesicular Transport; Chiroptera; Interferon Type I; Marmota
PubMed: 38612565
DOI: 10.3390/ijms25073753 -
Cellular and Molecular Gastroenterology... 2023
Topics: Hepatitis B virus; Nucleocapsid; Cell Line
PubMed: 36572389
DOI: 10.1016/j.jcmgh.2022.11.012