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CccDNA dynamics

Jing-Tao Huang, Ying Yang, Yi-Min Hu, Xing-Hui Liu, Mei-Yan Liao, Roy Morgan, Er-Feng Yuan, Xia Li, Song-Mei Liu
Despite implications of persistence of hepatitis B virus (HBV) covalently closed circular DNA (cccDNA) in the development of hepatocellular carcinoma (HCC), little is known about serum cccDNA in HBV-infected diseases. We developed a cccDNA-selective droplet digital PCR (ddPCR) to assess cccDNA content and dynamics across different stages of HCC development. One hundred forty-seven serum samples and 35 formalin-fixed, paraffin-embedded tumor tissues were derived from patients with HCC or HBV hepatitis/cirrhosis...
May 2018: Journal of Molecular Diagnostics: JMD
Yuji Ishida, Tje Lin Chung, Michio Imamura, Nobuhiko Hiraga, Suranjana Sen, Hiroshi Yokomichi, Chise Tateno, Laetitia Canini, Alan S Perelson, Susan L Uprichard, Harel Dahari, Kazuaki Chayama
BACKGROUND: Chimeric uPA/SCID mice reconstituted with humanized livers are useful for studying HBV infection in the absence of an adaptive immune response. However, the detailed characterization of HBV infection kinetics necessary to enable in-depth mechanistic studies in this novel in vivo HBV infection model is lacking. METHODS: To characterize HBV kinetics post-inoculation (p.i.) to steady state, 42 mice were inoculated with HBV. Serum HBV DNA was frequently measured from 1 minute to 63 days p...
March 23, 2018: Hepatology: Official Journal of the American Association for the Study of Liver Diseases
Quentin Cangelosi, Shawn A Means, Harvey Ho
Chronic hepatitis B viral infection (HBV) afflicts around 250 million individuals globally and few options for treatment exist. Once infected, the virus entrenches itself in the liver with a notoriously resilient colonisation of viral DNA (covalently-closed circular DNA, cccDNA). The majority of infections are cleared, yet we do not understand why 5% of adult immune responses fail leading to the chronic state with its collateral morbid effects such as cirrhosis and eventual hepatic carcinoma. The liver environment exhibits particularly complex spatial structures for metabolic processing and corresponding distributions of nutrients and transporters that may influence successful HBV entrenchment...
2017: PloS One
Jing Wang, Yiqi Yu, Guojun Li, Chuan Shen, Zhefeng Meng, Jianming Zheng, Yanhong Jia, Shaolong Chen, Xiao Zhang, Mengqi Zhu, Jiangjiang Zheng, Zhangzhang Song, Jing Wu, Lingyun Shao, Peiyu Qian, Xiaona Mao, Xuanyi Wang, Yuxian Huang, Caiyan Zhao, Jiming Zhang, Chao Qiu, Wenhong Zhang
BACKGROUND & AIMS: In diagnostics, serum hepatitis B virus (HBV)-RNA levels are valuable when the HBV-DNA load in circulation is effectively suppressed by nucleos(t)ide analogue (NUC) therapy. This study aimed to determine the intrahepatic viral replication activity reflected in serum HBV-RNA and whether HBV-RNA contributes to liver histological changes in patients treated with NUC. METHODS: A cross-sectional set of serum and liver biopsy samples was obtained from patients treated with entecavir, who had undetectable levels of serum HBV-DNA...
September 21, 2017: Journal of Hepatology
Francesca Guerrieri, Laura Belloni, Daniel D'Andrea, Natalia Pediconi, Loredana Le Pera, Barbara Testoni, Cecilia Scisciani, Oceane Floriot, Fabien Zoulim, Anna Tramontano, Massimo Levrero
BACKGROUND: The Hepatitis B Virus (HBV) HBx regulatory protein is required for HBV replication and involved in HBV-related carcinogenesis. HBx interacts with chromatin modifying enzymes and transcription factors to modulate histone post-translational modifications and to regulate viral cccDNA transcription and cellular gene expression. Aiming to identify genes and non-coding RNAs (ncRNAs) directly targeted by HBx, we performed a chromatin immunoprecipitation sequencing (ChIP-Seq) to analyse HBV recruitment on host cell chromatin in cells replicating HBV...
February 17, 2017: BMC Genomics
Claudia Minosse, Sabrina Coen, Ubaldo Visco Comandini, Raffaella Lionetti, Marzia Montalbano, Stefano Cerilli, Donatella Vincenti, Andrea Baiocchini, Maria R Capobianchi, Stefano Menzo
BACKGROUND: A functional cure of chronic hepatitis B (CHB) is feasible, but a clear view of the intrahepatic viral dynamics in each patient is needed. Intrahepatic covalently closed circular DNA (cccDNA) is the stable form of the viral genome in infected cells, and represents the ideal marker of parenchymal colonization. Its relationships with easily accessible peripheral parameters need to be elucidated in order to avoid invasive procedures in patients. OBJECTIVES: The goal of this study was to design, set up, and validate a reliable and straightforward method for the quantification of the cccDNA and total DNA of the hepatitis B virus (HBV) in a variety of clinical samples...
October 2016: Hepatitis Monthly
Ashish Goyal, John M Murray
Cell-free virus is a well-recognized and efficient mechanism for the spread of hepatitis B virus (HBV) infection in the liver. Cell-to-cell transmission (CCT) can be a more efficient means of virus propagation. Despite experimental evidence implying CCT occurs in HBV, its relative impact is uncertain. We develop a 3-D agent-based model where each hepatocyte changes its viral state according to a dynamical process driven by cell-free virus infection, CCT and intracellular replication. We determine the relative importance of CCT in the development and resolution of acute HBV infection in the presence of cytolytic (CTL) and non-CTL mechanisms...
2016: PloS One
Ashish Goyal, John M Murray
UNLABELLED: Hepatitis-D virus (HDV) is a satellite virus of hepatitis-B virus (HBV) whose intracellular products are required for the completion of the HDV life cycle. HDV can replicate in a cell without the presence of HBV but needs hepatitis B surface antigen (HBsAg) to complete virus assembly and packaging. In order to better understand HDV dynamics, we developed a mathematical model and successfully simulated HBV and HDV data under a range of scenarios. Compared to HBV mono-infection, dual HDV infection resulted in lower chronic HBV DNA levels, with more marked suppression for coinfection (1 logs HBV DNA copies/ml lower) compared to superinfection (0...
June 7, 2016: Journal of Theoretical Biology
John M Murray, Ashish Goyal
UNLABELLED: The progression of acute hepatitis B virus (HBV) to chronic infection or clearance is highly dependent on the host immune response composed of cytolytic (CTL) and non-cytolytic (non-CTL) effects. Cytolytic processes induce hepatocyte killing while non-CTL processes inhibit intracellular replication. Both effects are widely recognized and accepted. However, there are uncertainties about the assistance provided by either the loss of covalently circular closed DNA (cccDNA) during cell proliferation or the emergence of refractory cells to immune mediated clearance...
February 7, 2015: Journal of Theoretical Biology
Qiang Liu, Juan Huang, Renyong Jia, Mingshu Wang, Dekang Zhu, Shun Chen, Mafeng Liu, Zhongqiong Yin, Yin Wang, Anchun Cheng
Over the course of duck hepatitis B virus (DHBV) replication, one type of RNA (pregenome/C RNA, 3.5 kb) that corresponds to the whole genome of DHBV is generated from the transcription of viral cccDNA. Previous work has proposed three functions for the pregenome/C RNA: it can serve as the pregenome and be packaged into the core protein during the process of replication, and it encodes the mRNA for both the capsid protein and the viral polymerase. However, little is known about the timing of these functions during the different stages of viral infection...
January 22, 2015: Virus Research
Q Zheng, Y Y Zhu, J Chen, Y R Liu, J You, J Dong, D W Zeng, L Y Gao, L H Chen, J J Jiang
Viral load reduction facilitates recovery of antiviral T-cell responses. Dynamic alterations in intrahepatic viraemia clearance and immune cell reactivity during the early phase of nucleoside analogue (NA) therapy and the impact of these changes on HBeAg seroconversion are unknown. Fifteen HBeAg-positive chronic hepatitis B (CHB) patients were treated with adefovir dipivoxil. T-cell reactivity to HBV core and surface antigens were tested using ELISPOT assay from baseline to week 48 post-treatment (at 4-week intervals)...
December 2014: Journal of Viral Hepatitis
Qiang Li, Furong Lu, Guohong Deng, Kaifa Wang
The contribution of covalently closed circular DNA (cccDNA) and dendritic cells (DCs) to the progression of chronic hepatitis B virus (HBV) infection remains largely unknown. A dynamic model with seven cell types was proposed based on the biological mechanisms of viral replication and the host immune response. The cccDNA self-amplification rate was found to be closely related to both the basic reproduction number of the virus and the immune response. The combination of the cccDNA self-amplification rate and the initial activated DC count induces rich dynamics...
September 21, 2014: Journal of Theoretical Biology
Joshua T Schiffer, Dave A Swan, Daniel Stone, Keith R Jerome
Most chronic viral infections are managed with small molecule therapies that inhibit replication but are not curative because non-replicating viral forms can persist despite decades of suppressive treatment. There are therefore numerous strategies in development to eradicate all non-replicating viruses from the body. We are currently engineering DNA cleavage enzymes that specifically target hepatitis B virus covalently closed circular DNA (HBV cccDNA), the episomal form of the virus that persists despite potent antiviral therapies...
2013: PLoS Computational Biology
Yi Tian, Weibing Yang, Jianxun Song, Yuzhang Wu, Bing Ni
Hepatocellular carcinoma (HCC) remains one of the most prevalent malignant diseases worldwide, and the majority of cases are related to hepatitis B virus (HBV) infection. Interactions between the HBV-encoded X (HBx) protein and host factors are known to play major roles in the onset and progression of HBV-related HCC. These dynamic molecular mechanisms are extremely complex and lead to prominent changes in the host genetic and epigenetic architecture. This review summarizes the current knowledge about HBx-induced epigenetic changes, including aberrations in DNA methylation, histone modifications, and microRNA expression, and their roles in HBV-infected liver cells and HBV-related HCC...
August 2013: Molecular and Cellular Biology
Liping Shi, Shaohua Li, Fang Shen, Haodong Li, Shuiming Qian, Daniel H S Lee, Jim Z Wu, Wengang Yang
Hepadnaviral covalently closed circular DNA (cccDNA) exists as an episomal minichromosome in the nucleus of virus-infected hepatocytes, and serves as the transcriptional template for the synthesis of viral mRNAs. To obtain insight on the structure of hepadnaviral cccDNA minichromosomes, we utilized ducks infected with the duck hepatitis B virus (DHBV) as a model and determined the in vivo nucleosome distribution pattern on viral cccDNA by the micrococcal nuclease (MNase) mapping and genome-wide PCR amplification of isolated mononucleosomal DHBV DNA...
September 2012: Journal of Virology
Chin-Liew Chong, Mong-Liang Chen, Yi-Chieh Wu, Kuen-Nan Tsai, Chien-Chiao Huang, Cheng-Po Hu, King-Song Jeng, Yu-Chi Chou, Chungming Chang
BACKGROUND: The covalently closed-circular DNA (cccDNA) of hepatitis B virus (HBV) is associated with viral persistence in HBV-infected hepatocytes. However, the regulation of cccDNA and its transcription in the host cells at different growth stages is not well understood. METHODS: We took advantages of a stably HBV-producing cell line, 1.3ES2, and examine the dynamic changes of HBV cccDNA, viral transcripts, and viral replication intermediates in different cellular growth stages...
2011: Journal of Biomedical Science
Rahmet Guner, Mustafa Karahocagil, Mehmet Buyukberber, Ozlem Kandemir, Onur Ural, Gaye Usluer, Dilara Inan, Iftihar Koksal, Nurcan Baykam, Kenan Hizel, Tansu Yamazhan, Saban Esen, Mehmet A Tasyaran
OBJECTIVE: The aim of this study was to demonstrate the relation between intrahepatic (IH) hepatitis B virus (HBV) covalently closed circular DNA (cccDNA) levels and the other HBV replicative intermediates and hepatocyte expression of HBV antigens. PATIENTS AND METHODS: Patients with hepatitis B surface antigen (HBsAg) positivity, hepatitis B early antigen negativity, serum HBV DNA levels 10 copies/ml or more, and constantly or intermittently increased alanine aminotransferase levels were included...
November 2011: European Journal of Gastroenterology & Hepatology
Qian Gong, Shu Chen, Jinjun Guo, Hang Sun, Guoxing Zheng, Qi Liu, Hong Ren, Song He
Hepatitis B Virus (HBV) covalently closed circular DNA (cccDNA) is the main replicative intermediate of HBV and is organized into minichromosomes by the interaction with histone and nonhistone proteins. The remodeling of HBV minichromosomes such as post-translational modifications of histone proteins plays an important role in regulating HBV replication. To determine whether other remodeling occurs in addition to acetylation of cccDNA-bound H3 histones in the presence of HBV replication, a cell culture replication model of HBV was used to assess the dynamic status of acetylation, phosphorylation, and methylation of cccDNA-bound H3 histones at various times after transient transfection of linear HBV DNA into human hepatoma, HepG2 cells...
June 2011: DNA and Cell Biology
Ke-kai Zhao, Qing Wang, Xiao-hui Miao, Wen-sheng Xu
OBJECTIVE: To confirm whether DHBV cccDNA could be detected in serum of DHBV-infected ducks after liver injury. METHODS: Twenty four ducks with persistent DHBV infection were divided into 4 groups with the following treatments: A, D-galactosamine (D-GalN, 2.2 g/kg) and lipopolysaccharide (LPS, 100 µg/kg); B, 10 mg/kg of carbon tetrachloride (CCl4) every 12 h twice following D-GalN and LPS; C, 15 mg/kg of CCl4 every 12 h twice following D-GalN and LPS; D, normal saline as normal control (NC)...
September 21, 2010: Zhonghua Yi Xue za Zhi [Chinese medical journal]
Ke-kai Zhao, Qing Wang, Xiao-hui Miao, Wen-sheng Xu
OBJECTIVE: To confirm whether it is feasible to detect HBV cccDNA based on an analysis of its stability and clearance dynamics in the blood of ducks. METHODS: Twelve 1-week-old ducklings were randomized into group A and group B, and each duckling was intravenously injected with 1 milliliter of serum containing 1.2 x 10(9) copies of HBV virion (group A) or plasmid pBS HBV 3.6 II (group B). At 0.25, 2, 4, 6, 8, 12, 24 and 32 h post-injection, serum HBV DNA level in each duckling was quantified by Real-time fluorescent PCR...
May 5, 2009: Zhonghua Yi Xue za Zhi [Chinese medical journal]
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