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Chiaho Shih, Ching-Chun Yang, Gansukh Choijilsuren, Chih-Hsu Chang, An-Ting Liou
This infographic about hepatitis B virus explores its replication cycle, natural history of infection and pathogenesis, and how this can be controlled and treated. Hepatitis B virus (HBV) is a common worldwide blood-borne pathogen. Chronic hepatitis B can progress to an inactive carrier state, and then, in some patients, give rise to cirrhosis and cancer of the liver, leading to death. An HBV surface-antigen vaccine is effective, but treatments are currently not curative. HBV replicates via reverse transcription...
February 27, 2018: Trends in Microbiology
Natalia Freitas, Tetyana Lukash, Sumedha Gunewardena, Benjamin Chappell, Betty L Slagle, Severin O Gudima
Five matching sets of non-malignant liver tissues and HCCs from individuals chronically infected with hepatitis B virus (HBV) were examined. The HBV genomic sequences were determined using overlapping PCR amplicons covering the entire viral genome. Four pairs of tissues were infected with HBV of genotype C, while one pair - with genotype B. HBV replication markers were found in all tissues. In majority of HCC samples, the levels of pre-genomic/pre-core RNA (pgRNA) and covalently closed circular DNA (cccDNA) were lower than those of liver tissue counterparts...
February 28, 2018: Journal of Virology
Smita Nair, Adam Zlotnick
Cytidine deaminases inhibit replication of broad range of DNA viruses by deaminating cytidines on single stranded DNA to generate uracil. While several lines of evidence have revealed HBV genome editing by deamination, it is still unclear which nucleic acid intermediate of HBV is modified. Hepatitis B virus has a relaxed circular double-stranded DNA (rcDNA) genome that is reverse transcribed within virus cores from a RNA template. The HBV genome also persists as covalently closed circular DNA (cccDNA) in the nucleus of an infected cell...
February 28, 2018: Journal of Virology
Yu Liu, Miaoxian Zhao, Mingxing Gong, Ying Xu, Cantao Xie, Haohui Deng, Xueying Li, Hongkai Wu, Zhanhui Wang
Chronic hepatitis B virus (HBV) infection is difficult to cure due to the presence of covalently closed circular DNA (cccDNA). Accumulating evidence indicates that the CRISPR/Cas9 system effectively disrupts HBV genome, including cccDNA, in vitro and in vivo. However, efficient delivery of CRISPR/Cas9 system to the liver or hepatocytes using an adeno-associated virus (AAV) vector remains challenging due to the large size of Cas9 from Streptococcus pyogenes (Sp). The recently identified Cas9 protein from Staphylococcus aureus (Sa) is smaller than SpCas9 and thus is able to be packaged into the AAV vector...
February 16, 2018: Antiviral Research
Min Wu, Jin Li, Lei Yue, Lu Bai, Yaming Li, Jieliang Chen, Xiaonan Zhang, Zhenghong Yuan
Hepatitis B virus (HBV) covalently closed circular DNA (cccDNA), existing in hepatocyte nuclei as a stable minichromosome, plays a central role in the life cycle of the virus and permits the persistence of infection. Despite being essential for HBV infection, little is known about the molecular mechanisms of cccDNA formation, regulation and degradation, and there is no therapeutic agents directly targeting cccDNA, fore mostly due to the lack of robust, reliable and quantifiable HBV cccDNA models. In this study, combined the Cre/loxP and sleeping beauty transposons system, we established HepG2-derived cell lines integrated with 2-60 copies of monomeric HBV genome flanked by loxP sites (HepG2-HBV/loxP)...
February 9, 2018: Antiviral Research
Jingying Qiu, Qineng Gong, Jian Gao, Wang Chen, Yinpeng Zhang, Xiaoke Gu, Daoquan Tang
As an ongoing search for potent non-nucleoside anti-HBV agents with novel structures, we described a series of phenyl propionamide derivatives (3a-b, 4a-e, 7a-g, 8a-h and 9a-b) by pharmacophore fusion strategy in the present work. All the compounds exhibited an anti-HBV activity to some extent. Among them, compounds 8d and 9b displayed most potent anti-HBV activity with IC50 values on HBV DNA replication of 0.46 and 0.14 μM, respectively. And the selective index values of 8d and 9b were more than 217.39 and 153...
December 16, 2017: European Journal of Medicinal Chemistry
D S Kostyushev, A P Zueva, S A Brezgin, A D Lipatnikov, V N Simirskii, D Glebe, E V Volchkova, G A Shipulin, V P Chulanov
AIM: To define the role of DNA-methyltransferases of type 1 and type 3A in hepatitis B viral cycle. MATERIAL AND METHODS: Human hepatoma cells HepG2 with stable expression of 1.1-mer HBV genome were transfected with vectors encoding DNA-methyltransferase 1 (DNMT1), DNA-methyltransferase 3A (DNMT3A) or were co-transfected with these vectors. Total HBV DNA copy number, relative expression of pregenomic RNA (pgRNA), S-protein-encoding RNA (S-RNA) and cccDNA were analyzed by quantitative and semi-quantitative real-time PCR-analysis with TaqMan probes for assessment of DNMTs-mediated effects on HBV...
2017: Terapevticheskiĭ Arkhiv
Sina Feustel, Fabiola Ayón-Pérez, Ana Sandoval-Rodriguez, Roberto Rodríguez-Echevarría, Homero Contreras-Salinas, Juan Armendáriz-Borunda, L V Sánchez-Orozco
Chronic hepatitis B infection treatment implicates a long-lasting treatment. M. oleifera extracts contain compounds with antiviral, antioxidant, and antifibrotic properties. In this study, the effect of M. oleifera was evaluated in Huh7 cells expressing either HBV genotypes C or H for the antiviral, antifibrotic, anti-inflammatory, and antioxidative responses. Huh7 cells were treated with an aqueous extract of M. oleifera (leaves) at doses of 0, 30, 45, or 60 μ g/mL. The replicative virus and TGF-β1 , CTGF , CAT , IFN-β1 , and pgRNA expressions were measured by real time...
2017: Journal of Immunology Research
Tianlun Zhou, Timothy Block, Fei Liu, Andrew S Kondratowicz, Liren Sun, Siddhartha Rawat, Jeffrey Branson, Fang Guo, Holly Micolochick Steuer, Hongyan Liang, Lauren Bailey, Chris Moore, Xiaohe Wang, Andy Cuconatti, Min Gao, Amy C H Lee, Troy Harasym, Tim Chiu, Dimitar Gotchev, Bruce Dorsey, Rene Rijnbrand, Michael J Sofia
In pursuit of novel therapeutics targeting the hepatitis B virus (HBV) infection, we evaluated a dihydroquinolizinone compound (DHQ-1) that in the nanomolar range reduced the production of virion and surface protein (HBsAg) in tissue culture. This compound also showed broad HBV genotype coverage, but was inactive against a panel of DNA and RNA viruses of other species. Oral administration of DHQ-1 in the AAV-HBV mouse model resulted in a significant reduction of serum HBsAg as soon as 4 days following the commencement of treatment...
January 2018: Antiviral Research
Hui Ling Ko, Tze Hau Lam, Huijin Ng, Jiaying Toh, Liang Wei Wang, Ee Chee Ren
BACKGROUND & AIMS: The Hepatitis B Virus (HBV) may gain entry into non-liver cells but does not actively replicate in them. We investigated the possibility that these cells possess mechanisms that block HBV core promoter (HBVCP) transcription, specifically absent in liver cells, which together with other liver-specific mechanisms, such as sodium-taurocholate cotransporting polypeptide-mediated entry, enable liver cells to effectively produce HBV. METHODS: Liver and non-liver cell lines were screened for their capacity to activate the HBVCP and synthesize pre-genomic RNA (pgRNA)...
September 5, 2017: Journal of Hepatology
Boris Halgand, Christophe Desterke, Lise Rivière, Guillaume Fallot, Mylène Sebagh, Julien Calderaro, Paulette Bioulac-Sage, Christine Neuveut, Marie-Annick Buendia, Didier Samuel, Cyrille Féray
Hepatitis B virus (HBV) is a major cause of hepatocellular carcinoma (HCC). However, very little is known about the replication of HBV in HCC tissues. PATIENTS AND METHODS: We analysed viral and cellular parameters in HCC (T) and non-tumor liver (NT) samples from 99 HBsAg-positive, virologically suppressed patients treated by tumour resection or liver transplantation. We examined total HBV DNA and RNA as well as covalently closed circular DNA (cccDNA) and pregenomic RNA (pgRNA), which are considered as markers of active HBV replication...
August 12, 2017: Hepatology: Official Journal of the American Association for the Study of Liver Diseases
Markus Gajer, Katharina Dörnbrack, Christine Rösler, Bernadette Schmid, Jürgen Beck, Michael Nassal
Hepadnaviruses, including human hepatitis B virus (HBV), replicate their tiny DNA genomes by protein-primed reverse transcription of a pregenomic (pg) RNA. Replication initiation as well as pgRNA encapsidation depend on the interaction of the viral polymerase, P protein, with the ε RNA element, featuring a lower and an upper stem, a central bulge, and an apical loop. The bulge, somehow assisted by the loop, acts as template for a P protein-linked DNA oligo that primes full-length minus-strand DNA synthesis...
August 2, 2017: Scientific Reports
Di Mu, Fang-Chao Yuan, Yu Chen, Xiao-Yan Jiang, Liang Yan, Ling-Yu Jiang, Jian-Ping Gong, Da-Zhi Zhang, Hong Ren, Yong Liao
Methodology for accurate quantification of intra-hepatic cccDNA has long been a technical challenge, yet it is highly desired in the clinic. Here, we developed a sensitive method for quantification of intrahepatic cccDNA in liver biopsies from patients, which allowed to predict patient's response to interferon therapy at baseline. Twenty-five patients with HBeAg+ CHB were recruited and liver biopsies were obtained at baseline and 1-year after interferon treatment, respectively. Both intrahepatic cccDNA and HBV DNA were absolutely quantified by a droplet digital PCR amplification system...
July 19, 2017: Scientific Reports
Zhuanchang Wu, Siyu Tan, Leiqi Xu, Lifen Gao, Haizhen Zhu, Chunhong Ma, Xiaohong Liang
Covalently closed circular DNA (cccDNA) in the hepatocytes nucleus is responsible for persistent infection of Hepatitis B virus (HBV). Current antiviral therapy drugs nucleos(t)ide analogs or interferon fail to eradicate HBV cccDNA. Genome editing technique provides an effective approach for HBV treatment through targeting viral cccDNA. Natronobacterium gregoryi Argonaute (NgAgo)-guide DNA (gDNA) system with powerful genome editing prompts us to explore its application in inhibiting HBV replication. Preliminary function verification indicated that NgAgo/EGFP-gDNA obviously inhibited EGFP expression...
July 12, 2017: Antiviral Research
Surya Agung Priyambada, Ryo Misaki, Toru Okamoto, Yuta Okamoto, Takao Ohashi, Keiji Ueda, Yoshiharu Matsuura, Kazuhito Fujiyama
Hepatitis B virus (HBV) is the smallest partially double-stranded DNA virus known to infect humans. Worldwide, more than 50% of hepatocellular carcinoma (HCC) cases are related to chronic Hepatitis B. Development of HCC from normal liver cells is characterized by changes in cell surface N-glycans, which can promote the invasive behavior of tumor cells, leading ultimately to the progression of cancer. However, little is understood about the cell surface N-glycans of HBV-infected liver cells. We try to address this by taking advantage of the HepAD38 cell line, which can replicate HBV in the absence of tetracycline [tet(-)] in growth medium...
June 20, 2017: Virus Research
Ningning Liu, Jinfang Zhang, Xiaohai Yang, Tong Jiao, Xin Zhao, Wenxia Li, Jianhua Zhu, Pu Yang, Jianping Jin, Jirun Peng, Zhiwei Li, Xin Ye
Hepatitis B virus (HBV)-encoded X protein (HBx) plays a critical role in HBV-related hepatocarcinoma development. In this study, we demonstrate that HBx is specifically modified by NEDD8. We found that E3 ligase HDM2 promotes NEDDylation of HBx to enhance HBx stability by preventing its ubiquitination-mediated degradation. Consistently, analysis of 160 hepatocellular carcinoma patient specimens indicated that the amount of HDM2 protein correlates with HBx protein level. We identified that HBx K91 and K95 as the key HBx NEDDylation sites and observed that the NEDDylation-deficient HBx has shorter half-life...
August 15, 2017: Journal of Virology
Jan Martin Berke, Pascale Dehertogh, Karen Vergauwen, Ellen Van Damme, Wendy Mostmans, Koen Vandyck, Frederik Pauwels
Hepatitis B virus (HBV) capsid assembly is a critical step in the propagation of the virus and is mediated by the core protein. Due to its multiple functions in the viral life cycle, core became an attractive target for new antiviral therapies. Capsid assembly modulators (CAMs) accelerate the kinetics of capsid assembly and prevent encapsidation of the polymerase-pregenomic RNA (Pol-pgRNA) complex, thereby blocking viral replication. CAM JNJ-632 is a novel and potent inhibitor of HBV replication in vitro across genotypes A to D...
August 2017: Antimicrobial Agents and Chemotherapy
Angela M Lam, Suping Ren, Christine Espiritu, Mollie Kelly, Vincent Lau, Lingjie Zheng, George D Hartman, Osvaldo A Flores, Klaus Klumpp
The hepatitis B virus (HBV) core protein serves multiple essential functions in the viral life cycle, and antiviral agents that target the core protein are being developed. Capsid assembly modulators (CAMs) are compounds that target core and misdirect capsid assembly, resulting in the suppression of HBV replication and virion production. Besides HBV DNA, circulating HBV RNA has been detected in patient serum and can be associated with the treatment response. Here we studied the effect of HBV CAMs on the production of extracellular HBV RNA using infected HepaRG cells and primary human hepatocytes...
August 2017: Antimicrobial Agents and Chemotherapy
J Zhang, J Ma, H Wang, L Guo, J Li
We aimed to investigate the potential role and mechanism of microRNA-30c (miR-30c) in the pathological development of chronic hepatitis B (CHB). The serum levels of miR-30c in hepatitis B virus (HBV) carrier Xinjiang Uygur patients with inactive, low-replicative, high-replicative and HBe antigen-positive CHB were investigated. HepG2 cells were co-transfected with pHBV1.3 and miR-30c mimic or inhibitor or scramble RNA. The effects of miR-30c dysregulation on HBV replication and gene expression, cell proliferation and cell cycle were then investigated...
May 4, 2017: Brazilian Journal of Medical and Biological Research, Revista Brasileira de Pesquisas Médicas e Biológicas
Yuanjie Liu, Hui Nie, Richeng Mao, Bidisha Mitra, Dawei Cai, Ran Yan, Ju-Tao Guo, Timothy M Block, Nadir Mechti, Haitao Guo
Hepatitis B virus (HBV) replicates its DNA genome through reverse transcription of a viral RNA pregenome. We report herein that the interferon (IFN) stimulated exoribonuclease gene of 20 KD (ISG20) inhibits HBV replication through degradation of HBV RNA. ISG20 expression was observed at basal level and was highly upregulated upon IFN treatment in hepatocytes, and knock down of ISG20 resulted in elevation of HBV replication and attenuation of IFN-mediated antiviral effect. The sequence element conferring the susceptibility of HBV RNA to ISG20-mediated RNA degradation was mapped at the HBV RNA terminal redundant region containing epsilon (ε) stem-loop...
April 2017: PLoS Pathogens
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