1
|
Pondé RADA, Amorim GDSP. Exchanges in the 'a' determinant of the hepatitis B virus surface antigen revisited. Virology 2024; 599:110184. [PMID: 39127000 DOI: 10.1016/j.virol.2024.110184] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2024] [Revised: 07/02/2024] [Accepted: 07/17/2024] [Indexed: 08/12/2024]
Abstract
The hepatitis B virus surface antigen's (HBsAg) 'a' determinant comprises a sequence of amino acid residues located in the major hydrophilic region of the S protein, whose exchanges are closely associated with compromising the antigenicity and immunogenicity of that antigen. The HBsAg is generally present in the bloodstream of individuals with acute or chronic hepatitis B virus (HBV) infection. It is classically known as the HBV infection marker, and is therefore the first marker to be investigated in the laboratory in the clinical hypothesis of infection by this agent. One of the factors that compromises the HBsAg detection in the bloodstream by the assays adopted in serological screening in both clinical contexts is the loss of S protein antigenicity. This can occur due to mutations that emerge in the HBV genome regions that encode the S protein, especially for its immunodominant region - the 'a' determinant. These mutations can induce exchanges of amino acid residues in the S protein's primary structure, altering its tertiary structure and the antigenic conformation, which may not be recognized by anti-HBs antibodies, compromising the infection diagnosis. In addition, these exchanges can render ineffective the anti-HBs antibodies action acquired by vaccination, compromise the effectiveness of the chronically HBV infected patient's treatment, and also the HBsAg immunogenicity, by promoting its retention within the cell. In this review, the residues exchange that alter the S protein's structure is revisited, as well as the mechanisms that lead to the HBsAg antigenicity loss, and the clinical, laboratory and epidemiological consequences of this phenomenon.
Collapse
Affiliation(s)
- Robério Amorim de Almeida Pondé
- Secretaria de Estado da Saúde -SES/Superintendência de Vigilância Em Saúde-SUVISA/GO, Gerência de Vigilância Epidemiológica de Doenças Transmissíveis-GVEDT/Coordenação de Análises e Pesquisas-CAP, Goiânia, Goiás, Brazil; Laboratory of Human Virology, Institute of Tropical Pathology and Public Health, Federal University of Goiás, Goiânia, Goiás, Brazil.
| | | |
Collapse
|
2
|
Li Z, Huang L, Yu C. Advanced Prediction of Hepatic Oncogenic Transformation in HBV Patients via RNA-Seq Data Analysis and Deep Learning Techniques. Int J Mol Sci 2024; 25:9827. [PMID: 39337315 PMCID: PMC11432201 DOI: 10.3390/ijms25189827] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2024] [Revised: 09/09/2024] [Accepted: 09/10/2024] [Indexed: 09/30/2024] Open
Abstract
Liver cancer, recognized as a significant global health issue, is increasingly correlated with Hepatitis B virus (HBV) infection, as evidenced by numerous scientific studies. This study aims to examine the correlation between HBV infection and the development of liver cancer, focusing on using RNA sequencing (RNA-seq) to detect HBV sequences and applying deep learning techniques to estimate the likelihood of oncogenic transformation in individuals with HBV. Our study utilized RNA-seq data and employed Pathseq software and sophisticated deep learning models, including a convolutional neural network (CNN), to analyze the prevalence of HBV sequences in the samples of patients with liver cancer. Our research successfully identified the prevalence of HBV sequences and demonstrated that the CNN model achieved an exceptional Area Under the Curve (AUC) of 0.998 in predicting cancerous transformations. We observed no viral synergism that enhanced the pathogenicity of HBV. A detailed analysis of sequences misclassified by the CNN model revealed that longer sequences were more conducive to accurate recognition. The findings from this study provide critical insights into the management and prognosis of patients infected with HBV, highlighting the potential of advanced analytical techniques in understanding the complex interactions between viral infections and cancer development.
Collapse
Affiliation(s)
| | | | - Changyuan Yu
- College of Life Science and Technology, Beijing University of Chemical Technology, Beijing 100029, China; (Z.L.)
| |
Collapse
|
3
|
Sun Q, Ni J, Li S, Ding H, Wang P, Song N, Wang X, Li M. Access to Reverse Glycosyl Azides and Rare Sugar-Based Glycosyl Azides via Radical Decarboxylative Azidation: Divergent Synthesis of 4'- C-Azidonucleosides as Potential Antiviral Agents. Org Lett 2024; 26:3997-4001. [PMID: 38687048 DOI: 10.1021/acs.orglett.4c01084] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/02/2024]
Abstract
The radical decarboxylative azidation of structurally diverse uronic acids has been established as an efficient approach to reverse glycosyl azides and rare sugar-derived glycosyl azides under the action of Ag2CO3, 3-pyridinesulfonyl azide, and K2S2O8. The power of this method has been highlighted by the divergent synthesis of 4'-C-azidonucleosides using Vorbrüggen glycosylation of nucleobases with 4-C-azidofuranosyl acetates. The antiviral assessment of the resulting nucleosides revealed one compound as a potential inhibitor of covalently closed circular DNA.
Collapse
Affiliation(s)
- Qikai Sun
- Key Laboratory of Marine Medicine, Chinese Ministry of Education, School of Medicine and Pharmacy, Ocean University of China, Qingdao 266003, China
| | - Jingxuan Ni
- Key Laboratory of Marine Medicine, Chinese Ministry of Education, School of Medicine and Pharmacy, Ocean University of China, Qingdao 266003, China
| | - Shanshan Li
- Key Laboratory of Marine Medicine, Chinese Ministry of Education, School of Medicine and Pharmacy, Ocean University of China, Qingdao 266003, China
| | - Han Ding
- Key Laboratory of Marine Medicine, Chinese Ministry of Education, School of Medicine and Pharmacy, Ocean University of China, Qingdao 266003, China
| | - Peng Wang
- Key Laboratory of Marine Medicine, Chinese Ministry of Education, School of Medicine and Pharmacy, Ocean University of China, Qingdao 266003, China
| | - Ni Song
- Key Laboratory of Marine Medicine, Chinese Ministry of Education, School of Medicine and Pharmacy, Ocean University of China, Qingdao 266003, China
- Laboratory for Marine Drugs and Bioproducts, Pilot National Laboratory for Marine Science and Technology, Qingdao 266237, China
| | - Xin Wang
- Key Laboratory of Marine Medicine, Chinese Ministry of Education, School of Medicine and Pharmacy, Ocean University of China, Qingdao 266003, China
- Key Laboratory of Tropical Biological Resources of Ministry of Education and One Health Institute, School of Pharmaceutical Sciences, Hainan University, Haikou 570228, China
- Song Li' Academician Workstation, School of Pharmaceutical Sciences, Hainan University, Sanya 572000, China
| | - Ming Li
- Key Laboratory of Marine Medicine, Chinese Ministry of Education, School of Medicine and Pharmacy, Ocean University of China, Qingdao 266003, China
- Laboratory for Marine Drugs and Bioproducts, Pilot National Laboratory for Marine Science and Technology, Qingdao 266237, China
| |
Collapse
|
4
|
Allweiss L, Cohen C, Dias J, Fumagalli V, Guo H, Harris JM, Hu J, Iannacone M, Isogawa M, Jeng WJ, Kim KH, Kramvis A, Li W, Lucifora J, Muramatsu M, Neuveut C, Ploss A, Pollicino T, Protzer U, Tan A, Tanaka Y, Tu T, Tsukuda S, Thimme R, Urban S, Watashi K, Yuan Z, Yeh SH, McKeating JA, Revill PA. Highlights from the 2023 International Meeting on the Molecular Biology of Hepatitis B virus. J Gen Virol 2024; 105:001978. [PMID: 38757942 PMCID: PMC11258880 DOI: 10.1099/jgv.0.001978] [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: 02/19/2024] [Accepted: 04/04/2024] [Indexed: 05/18/2024] Open
Abstract
Since its discovery in 1965, our understanding of the hepatitis B virus (HBV) replication cycle and host immune responses has increased markedly. In contrast, our knowledge of the molecular biology of hepatitis delta virus (HDV), which is associated with more severe liver disease, is less well understood. Despite the progress made, critical gaps remain in our knowledge of HBV and HDV replication and the mechanisms underlying viral persistence and evasion of host immunity. The International HBV Meeting is the leading annual scientific meeting for presenting the latest advances in HBV and HDV molecular virology, immunology, and epidemiology. In 2023, the annual scientific meeting was held in Kobe, Japan and this review summarises some of the advances presented at the Meeting and lists gaps in our knowledge that may facilitate the development of new therapies.
Collapse
Affiliation(s)
- HBV2023
- Various- see supplementary material
| | - Lena Allweiss
- Department of Internal Medicine, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
- German Center for Infection Research (DZIF), Braunschweig, Germany
| | | | - Joao Dias
- Laboratoire de Virologie Moléculaire, CNRS Université de Montpellier, Montpellier, France
| | - Valeria Fumagalli
- Division of Immunology, Transplantation and Infectious Diseases, IRCCS San Raffaele Scientific Institute, 20132 Milan, Italy
- Vita-Salute San Raffaele University, 20132 Milan, Italy
| | - Haitao Guo
- Department of Microbiology and Molecular Genetics; Cancer Virology Program, UPMC Hillman Cancer Center, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA
| | - James M. Harris
- Nuffield Department of Medicine, University of Oxford, Oxford, UK
| | - Jianming Hu
- Department of Microbiology and Immunology, The Pennsylvania State University College of Medicine, Hershey, PA, USA
| | - Matteo Iannacone
- Division of Immunology, Transplantation and Infectious Diseases, IRCCS San Raffaele Scientific Institute, 20132 Milan, Italy
- Vita-Salute San Raffaele University, 20132 Milan, Italy
| | - Masanori Isogawa
- Department of Virology II, National Institute of Infectious Diseases, Tokyo, Japan
| | - Wen-Juei Jeng
- Department of Gastroenterology and Hepatology, Chang Gung Memorial Hospital, Linkou Medical Center, Chang Gung University, Taoyuan, Taiwan, ROC
| | - Kyun-Hwan Kim
- Department of Precision Medicine, School of Medicine, Sungkyunkwan University, Suwon, Republic of Korea
| | - Anna Kramvis
- Anna Kramvis Hepatitis Virus Diversity Research Unit, Department of Internal Medicine, School of Clinical Medicine, University of the Witwatersrand, Johannesburg, South Africa
| | - Wenhui Li
- National Institute of Biological Sciences, Beijing, PR China
- Tsinghua Institute of Multidisciplinary Biomedical Research, Tsinghua University, Beijing, PR China
| | - Julie Lucifora
- CIRI, Centre International de Recherche en Infectiologie, Univ Lyon, Inserm, U1111, Université Claude Bernard Lyon 1, CNRS, UMR5308, ENS de Lyon, F-69007, Lyon, France
| | - Masamichi Muramatsu
- Department of Infectious Disease Research, Institute of Biomedical Research and Innovation, Foundation for Biomedical Research and Innovation at Kobe, Kobe, Hyogo, Japan
| | - Christine Neuveut
- Laboratoire de Virologie Moléculaire, CNRS Université de Montpellier, Montpellier, France
| | - Alexander Ploss
- Department of Molecular Biology, Princeton University, Princeton, NJ, USA
| | - Teresa Pollicino
- Department of Clinical and Experimental Medicine, University Hospital of Messina, Messina, Italy
| | - Ulrike Protzer
- German Center for Infection Research (DZIF), Braunschweig, Germany
- Institute of Virology, School of Medicine and Health, Technical University of Munich/Helmholtz Munich, Munich, Germany
| | - Anthony Tan
- Emerging Infectious Diseases, Duke-NUS Medical School, Singapore, Singapore
| | - Yasuhito Tanaka
- Department of Gastroenterology and Hepatology, Faculty of Life Sciences, Kumamoto University, Kumamoto 860-8556, Japan
| | - Thomas Tu
- Storr Liver Centre, The Westmead Institute for Medical Research, The University of Sydney at Westmead Hospital, Westmead, NSW, Australia
- Centre for Infectious Diseases and Microbiology, Sydney Infectious Diseases Institute, The University of Sydney at Westmead Hospital, Westmead, NSW, Australia
| | - Senko Tsukuda
- Nuffield Department of Medicine, University of Oxford, Oxford, UK
| | - Robert Thimme
- Department of Medicine II, University Hospital Freiburg, Breisgau, Germany
| | - Stephan Urban
- German Center for Infection Research (DZIF), Braunschweig, Germany
| | - Koichi Watashi
- Research Center for Drug and Vaccine Development, National Institute of Infectious Diseases, Tokyo, Japan
| | - Zhenghong Yuan
- Key Lab of Medical Molecular Virology, Shanghai Medical College, Fudan University, Shanghai, PR China
| | - Shiou-Hwei Yeh
- Graduate Institute of Microbiology, National Taiwan University College of Medicine, Taipei, Taiwan, ROC
- Department of Clinical Laboratory Sciences and Medical Biotechnology, National Taiwan University College of Medicine, Taipei, Taiwan, ROC
| | - Jane A. McKeating
- Nuffield Department of Medicine, University of Oxford, Oxford, UK
- Chinese Academy of Medical Sciences Oxford Institute, University of Oxford, Oxford, UK
| | - Peter A. Revill
- Victorian Infectious Diseases Reference Laboratory, Royal Melbourne Hospital at the Peter Doherty Institute for Infection and Immunity, Parkville, Victoria, Australia
- Department of Infectious Diseases, University of Melbourne, Parkville, Victoria, Australia
| |
Collapse
|
5
|
Yamasaki M, Sawa R, Muramatsu H, Yamamoto Y, Umekita M, Kubota Y, Kanegae Y, Igarashi M. Catenulopyrizomicins, new anti-Hepatitis B virus compounds, from the rare actinomycete Catenuloplanes sp. MM782L-181F7. J Antibiot (Tokyo) 2024; 77:85-92. [PMID: 38008738 DOI: 10.1038/s41429-023-00681-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2023] [Revised: 10/31/2023] [Accepted: 11/01/2023] [Indexed: 11/28/2023]
Abstract
Hepatitis B virus (HBV) causes chronic hepatitis in humans, and current antiviral therapies rarely treat viral infections. To improve the treatment efficacy, novel therapeutic agents, especially those with different mechanisms of action, need to be developed for use in combination with the current antivirals. Here, we isolated new anti-HBV compounds, named catenulopyrizomicins A-C, from the fermentation broth of rare actinomycete Catenuloplanes sp. MM782L-181F7. Structural analysis revealed that these compounds contained a structure that is composed of thiazolyl pyridine moiety. The catenulopyrizomicins reduced the amount of intracellular viral DNA in HepG2.2.15 cells with EC50 values ranging from 1.94 to 2.63 µM with small but notable selectivity. Mechanistic studies indicated that catenulopyrizomicin promotes the release of immature virion particles that fail to be enveloped through alterations in membrane permeability.
Collapse
Affiliation(s)
- Manabu Yamasaki
- Institute of Microbial Chemistry (BIKAKEN), Shinagawa-ku, Tokyo, Japan.
| | - Ryuichi Sawa
- Institute of Microbial Chemistry (BIKAKEN), Shinagawa-ku, Tokyo, Japan
| | | | - Yui Yamamoto
- Institute of Microbial Chemistry (BIKAKEN), Shinagawa-ku, Tokyo, Japan
| | - Maya Umekita
- Institute of Microbial Chemistry (BIKAKEN), Shinagawa-ku, Tokyo, Japan
| | - Yumiko Kubota
- Institute of Microbial Chemistry (BIKAKEN), Shinagawa-ku, Tokyo, Japan
| | - Yumi Kanegae
- Core Research Facilities of Basic Science, Research Center for Medical Science, The Jikei University School of Medicine, Minato-ku, Tokyo, Japan
| | - Masayuki Igarashi
- Institute of Microbial Chemistry (BIKAKEN), Shinagawa-ku, Tokyo, Japan
| |
Collapse
|
6
|
Zheng Y, Deng Q. The Cre/loxP-Based Recombinant HBV cccDNA System In Vitro and In Vivo. Methods Mol Biol 2024; 2837:185-198. [PMID: 39044085 DOI: 10.1007/978-1-0716-4027-2_16] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/25/2024]
Abstract
Covalently closed circular DNA (cccDNA) exists as a stable episomal minichromosome in the nucleus of hepatocytes and is responsible for hepatitis B virus (HBV) persistence. We recently reported a technique involving recombinant cccDNA (rcccDNA) of HBV by site-specific DNA recombination. A floxed monomeric HBV genome was engineered into a precursor plasmid (prcccDNA) which was excised via Cre/loxP-mediated DNA recombination to form a 3.3-kb rcccDNA bearing a loxP-chimeric intron. The foreign sequence was efficiently removed during RNA splicing, rendering a functionally seamless insertion. We characterized rcccDNA formation, effective viral transcription, and replication induced by rcccDNA both in vitro and in vivo. Furthermore, we closely simulated chronic hepatitis by using a replication-defective recombinant adenoviral vector to deliver rcccDNA to the transgenic mice expressing Cre recombinase, which led to prominent HBV persistence. Here, we describe a detailed protocol about how to construct and evaluate Cre/loxP-based recombinant HBV cccDNA system both in vitro and in vivo.
Collapse
Affiliation(s)
- Yuan Zheng
- Key Laboratory of Medical Molecular Virology (MOE/NHC/CAMS), School of Basic Medical Sciences, Fudan University, Shanghai, China
- Shanghai Institute of Infectious Disease and Biosecurity, Shanghai, China
| | - Qiang Deng
- Key Laboratory of Medical Molecular Virology (MOE/NHC/CAMS), School of Basic Medical Sciences, Fudan University, Shanghai, China.
- Shanghai Institute of Infectious Disease and Biosecurity, Shanghai, China.
| |
Collapse
|
7
|
Nayak S, Gowda J, Abbas SA, Kim H, Han SB. Recent Advances in the Development of Sulfamoyl-Based Hepatitis B Virus Nucleocapsid Assembly Modulators. Viruses 2023; 15:2367. [PMID: 38140607 PMCID: PMC10747759 DOI: 10.3390/v15122367] [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: 10/15/2023] [Revised: 11/24/2023] [Accepted: 11/27/2023] [Indexed: 12/24/2023] Open
Abstract
Hepatitis B virus (HBV) is the primary contributor to severe liver ailments, encompassing conditions such as cirrhosis and hepatocellular carcinoma. Globally, 257 million people are affected by HBV annually and 887,000 deaths are attributed to it, representing a substantial health burden. Regrettably, none of the existing therapies for chronic hepatitis B (CHB) have achieved satisfactory clinical cure rates. This issue stems from the existence of covalently closed circular DNA (cccDNA), which is difficult to eliminate from the nucleus of infected hepatocytes. HBV genetic material is composed of partially double-stranded DNA that forms complexes with viral polymerase inside an icosahedral capsid composed of a dimeric core protein. The HBV core protein, consisting of 183 to 185 amino acids, plays integral roles in multiple essential functions within the HBV replication process. In this review, we describe the effects of sulfamoyl-based carboxamide capsid assembly modulators (CAMs) on capsid assembly, which can suppress HBV replication and disrupt the production of new cccDNA. We present research on classical, first-generation sulfamoyl benzocarboxamide CAMs, elucidating their structural composition and antiviral efficacy. Additionally, we explore newly identified sulfamoyl-based CAMs, including sulfamoyl bicyclic carboxamides, sulfamoyl aromatic heterocyclic carboxamides, sulfamoyl aliphatic heterocyclic carboxamides, cyclic sulfonamides, and non-carboxamide sulfomoyl-based CAMs. We believe that certain molecules derived from sulfamoyl groups have the potential to be developed into essential components of a well-suited combination therapy, ultimately yielding superior clinical efficacy outcomes in the future.
Collapse
Affiliation(s)
- Sandesha Nayak
- Therapeutics and Biotechnology Division, Korea Research Institute of Chemical Technology, Daejeon 34114, Republic of Korea
- Department of Medicinal Chemistry and Pharmacology, University of Science & Technology, Daejeon 34113, Republic of Korea
| | - Jayaraj Gowda
- Therapeutics and Biotechnology Division, Korea Research Institute of Chemical Technology, Daejeon 34114, Republic of Korea
- Department of Medicinal Chemistry and Pharmacology, University of Science & Technology, Daejeon 34113, Republic of Korea
| | - Syed Azeem Abbas
- Therapeutics and Biotechnology Division, Korea Research Institute of Chemical Technology, Daejeon 34114, Republic of Korea
- Department of Medicinal Chemistry and Pharmacology, University of Science & Technology, Daejeon 34113, Republic of Korea
| | - Hyejin Kim
- Therapeutics and Biotechnology Division, Korea Research Institute of Chemical Technology, Daejeon 34114, Republic of Korea
| | - Soo Bong Han
- Therapeutics and Biotechnology Division, Korea Research Institute of Chemical Technology, Daejeon 34114, Republic of Korea
- Department of Medicinal Chemistry and Pharmacology, University of Science & Technology, Daejeon 34113, Republic of Korea
| |
Collapse
|
8
|
Ruengsatra T, Meeprasert A, Rattanangkool E, Deesiri S, Srisa J, Udomnilobol U, Dunkoksung W, Chuaypen N, Kiatbumrung R, Tangkijvanich P, Vimolmangkang S, Pudhom K, Prueksaritanont T. Binding characteristics of pyrrole-scaffold hepatitis B virus capsid inhibitors and identification of novel potent compounds. RSC Adv 2023; 13:29004-29022. [PMID: 37807973 PMCID: PMC10556424 DOI: 10.1039/d3ra04720b] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2023] [Accepted: 09/24/2023] [Indexed: 10/10/2023] Open
Abstract
Hepatitis B virus (HBV) capsid assembly modulators (CAMs) are currently being evaluated in clinical trials as potential curative therapies for HBV. This study used in silico computational modeling to provide insights into the binding characteristics between the HBV core protein and two pyrrole-scaffold inhibitors, JNJ-6379 and GLP-26, both in the CAM-Normal (CAM-N) series. Molecular dynamics simulations showed that the pyrrole inhibitors displayed similar general binding-interaction patterns to NVR 3-778, another CAM-N, with hydrophobic interactions serving as the major driving force. However, consistent with their higher potency, the pyrrole inhibitors exhibited stronger nonpolar interactions with key residues in a solvent-accessible region as compared to NVR 3-778. This feature was facilitated by distinct hydrogen bond interactions of the pyrrole scaffold inhibitors with the residue 140 in chain B of the HBV core protein (L140B). Based on these findings, novel CAM-N compounds were designed to mimic the interaction with L140B residue while maximizing nonpolar interactions in the solvent-accessible region. Several 1H-pyrrole-2-carbonyl substituted pyrrolidine-based compounds with various hydrophobic side chains were synthesized and evaluated. Through analyses of the structure-activity and structure-druggability relations of a series of compounds, CU15 emerged as the most promising lead CAM-N compound, exhibiting sub-nanomolar potency and good pharmacokinetic profiles. Overall, the study demonstrated a practical approach to leverage computational methods for understanding key target binding features for rationale-based design, and for guiding the identification of novel compounds.
Collapse
Affiliation(s)
- Tanachote Ruengsatra
- Chulalongkorn University Drug Discovery and Drug Development Research Center (Chula4DR), Chulalongkorn University 254 Phayathai Rd, Prathumwan Bangkok 10330 Thailand
| | - Arthitaya Meeprasert
- Chulalongkorn University Drug Discovery and Drug Development Research Center (Chula4DR), Chulalongkorn University 254 Phayathai Rd, Prathumwan Bangkok 10330 Thailand
| | - Eakkaphon Rattanangkool
- Chulalongkorn University Drug Discovery and Drug Development Research Center (Chula4DR), Chulalongkorn University 254 Phayathai Rd, Prathumwan Bangkok 10330 Thailand
| | - Sirikan Deesiri
- Chulalongkorn University Drug Discovery and Drug Development Research Center (Chula4DR), Chulalongkorn University 254 Phayathai Rd, Prathumwan Bangkok 10330 Thailand
| | - Jakkrit Srisa
- Chulalongkorn University Drug Discovery and Drug Development Research Center (Chula4DR), Chulalongkorn University 254 Phayathai Rd, Prathumwan Bangkok 10330 Thailand
| | - Udomsak Udomnilobol
- Chulalongkorn University Drug Discovery and Drug Development Research Center (Chula4DR), Chulalongkorn University 254 Phayathai Rd, Prathumwan Bangkok 10330 Thailand
| | - Wilasinee Dunkoksung
- Chulalongkorn University Drug Discovery and Drug Development Research Center (Chula4DR), Chulalongkorn University 254 Phayathai Rd, Prathumwan Bangkok 10330 Thailand
| | - Natthaya Chuaypen
- Chulalongkorn University Drug Discovery and Drug Development Research Center (Chula4DR), Chulalongkorn University 254 Phayathai Rd, Prathumwan Bangkok 10330 Thailand
- Center of Excellence in Hepatitis and Liver Cancer, Department of Biochemistry, Faculty of Medicine, Chulalongkorn University Bangkok Thailand
| | - Rattanaporn Kiatbumrung
- Chulalongkorn University Drug Discovery and Drug Development Research Center (Chula4DR), Chulalongkorn University 254 Phayathai Rd, Prathumwan Bangkok 10330 Thailand
- Center of Excellence in Hepatitis and Liver Cancer, Department of Biochemistry, Faculty of Medicine, Chulalongkorn University Bangkok Thailand
| | - Pisit Tangkijvanich
- Chulalongkorn University Drug Discovery and Drug Development Research Center (Chula4DR), Chulalongkorn University 254 Phayathai Rd, Prathumwan Bangkok 10330 Thailand
- Center of Excellence in Hepatitis and Liver Cancer, Department of Biochemistry, Faculty of Medicine, Chulalongkorn University Bangkok Thailand
| | - Sornkanok Vimolmangkang
- Department of Pharmacognosy and Pharmaceutical Botany, Faculty of Pharmaceutical Sciences, Chulalongkorn University Bangkok Thailand
| | - Khanitha Pudhom
- Department of Chemistry, Faculty of Science, Chulalongkorn University Bangkok Thailand
| | - Thomayant Prueksaritanont
- Chulalongkorn University Drug Discovery and Drug Development Research Center (Chula4DR), Chulalongkorn University 254 Phayathai Rd, Prathumwan Bangkok 10330 Thailand
| |
Collapse
|
9
|
Olenginski LT, Attionu SK, Henninger EN, LeBlanc RM, Longhini AP, Dayie TK. Hepatitis B Virus Epsilon (ε) RNA Element: Dynamic Regulator of Viral Replication and Attractive Therapeutic Target. Viruses 2023; 15:1913. [PMID: 37766319 PMCID: PMC10534774 DOI: 10.3390/v15091913] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2023] [Revised: 09/01/2023] [Accepted: 09/05/2023] [Indexed: 09/29/2023] Open
Abstract
Hepatitis B virus (HBV) chronically infects millions of people worldwide, which underscores the importance of discovering and designing novel anti-HBV therapeutics to complement current treatment strategies. An underexploited but attractive therapeutic target is ε, a cis-acting regulatory stem-loop RNA situated within the HBV pregenomic RNA (pgRNA). The binding of ε to the viral polymerase protein (P) is pivotal, as it triggers the packaging of pgRNA and P, as well as the reverse transcription of the viral genome. Consequently, small molecules capable of disrupting this interaction hold the potential to inhibit the early stages of HBV replication. The rational design of such ligands necessitates high-resolution structural information for the ε-P complex or its individual components. While these data are currently unavailable for P, our recent structural elucidation of ε through solution nuclear magnetic resonance spectroscopy marks a significant advancement in this area. In this review, we provide a brief overview of HBV replication and some of the therapeutic strategies to combat chronic HBV infection. These descriptions are intended to contextualize our recent experimental efforts to characterize ε and identify ε-targeting ligands, with the ultimate goal of developing novel anti-HBV therapeutics.
Collapse
Affiliation(s)
- Lukasz T. Olenginski
- Center for Biomolecular Structure and Organization, Department of Chemistry and Biochemistry, University of Maryland, College Park, MD 20742, USA (R.M.L.)
- Department of Biochemistry, University of Colorado, Boulder, CO 80309, USA
| | - Solomon K. Attionu
- Center for Biomolecular Structure and Organization, Department of Chemistry and Biochemistry, University of Maryland, College Park, MD 20742, USA (R.M.L.)
| | - Erica N. Henninger
- Center for Biomolecular Structure and Organization, Department of Chemistry and Biochemistry, University of Maryland, College Park, MD 20742, USA (R.M.L.)
| | - Regan M. LeBlanc
- Center for Biomolecular Structure and Organization, Department of Chemistry and Biochemistry, University of Maryland, College Park, MD 20742, USA (R.M.L.)
| | - Andrew P. Longhini
- Center for Biomolecular Structure and Organization, Department of Chemistry and Biochemistry, University of Maryland, College Park, MD 20742, USA (R.M.L.)
- Neuroscience Research Institute, University of California, Santa Barbara, Santa Barbara, CA 93106, USA
- Department of Molecular, Cellular and Developmental Biology, University of California, Santa Barbara, Santa Barbara, CA 93106, USA
| | - Theodore K. Dayie
- Center for Biomolecular Structure and Organization, Department of Chemistry and Biochemistry, University of Maryland, College Park, MD 20742, USA (R.M.L.)
| |
Collapse
|
10
|
Duchemin NJ, Loonawat R, Yeakle K, Rosenkranz A, Bouchard MJ. Hypoxia-inducible factor affects hepatitis B virus transcripts and genome levels as well as the expression and subcellular location of the hepatitis B virus core protein. Virology 2023; 586:76-90. [PMID: 37490813 DOI: 10.1016/j.virol.2023.06.013] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2021] [Revised: 06/13/2023] [Accepted: 06/21/2023] [Indexed: 07/27/2023]
Abstract
Globally, a chronic-hepatitis B virus (HBV) infection is the leading cause of hepatocellular carcinoma (HCC). The transcription factor hypoxia-inducible factor 1 (HIF1) is often elevated in HCC, including HBV-associated HCC. Previous studies have suggested that the expression of the HIF1 subunit, HIF1α, is elevated in HBV-infected hepatocytes; however, whether HIF1 activity affects the HBV lifecycle has not been fully explored. We used a liver-derived cell line and ex vivo cultured primary hepatocytes as models to determine how HIF1 affects the HBV lifecycle. We observed that HIF1 elevates HBV RNA transcript levels, core protein levels, core protein localization to the cytoplasm, and HBV genome replication. Attenuating the transcription activity of HIF1 blocked HIF1-mediated effects on the HBV lifecycle. Our studies show that HIF1 regulates various stages of the HBV lifecycle in hepatocytes and could be a therapeutic target for blocking HBV replication and the development of HBV-associated diseases.
Collapse
Affiliation(s)
- Nicholas J Duchemin
- Molecular and Cellular Biology and Genetic Graduate Program, Graduate School of Biomedical Sciences and Professional Studies, Drexel University College of Medicine, USA
| | - Ronak Loonawat
- Microbiology and Immunology Graduate Program, Graduate School of Biomedical Sciences and Professional Studies, Drexel University College of Medicine, USA
| | - Kyle Yeakle
- Molecular and Cellular Biology and Genetic Graduate Program, Graduate School of Biomedical Sciences and Professional Studies, Drexel University College of Medicine, USA
| | - Andrea Rosenkranz
- Molecular and Cellular Biology and Genetic Graduate Program, Graduate School of Biomedical Sciences and Professional Studies, Drexel University College of Medicine, USA
| | - Michael J Bouchard
- Department of Biochemistry and Molecular Biology, Drexel University College of Medicine, Philadelphia, PA, 19102, USA.
| |
Collapse
|
11
|
Hofmann S, Plank V, Groitl P, Skvorc N, Hofmann K, Luther J, Ko C, Zimmerman P, Bruss V, Stadler D, Carpentier A, Rezk S, Nassal M, Protzer U, Schreiner S. SUMO Modification of Hepatitis B Virus Core Mediates Nuclear Entry, Promyelocytic Leukemia Nuclear Body Association, and Efficient Formation of Covalently Closed Circular DNA. Microbiol Spectr 2023; 11:e0044623. [PMID: 37199632 PMCID: PMC10269885 DOI: 10.1128/spectrum.00446-23] [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: 02/05/2023] [Accepted: 04/24/2023] [Indexed: 05/19/2023] Open
Abstract
Persistence of hepatitis B virus (HBV) infection is due to a nuclear covalently closed circular DNA (cccDNA), generated from the virion-borne relaxed circular DNA (rcDNA) genome in a process likely involving numerous cell factors from the host DNA damage response (DDR). The HBV core protein mediates rcDNA transport to the nucleus and likely affects stability and transcriptional activity of cccDNA. Our study aimed at investigating the role of HBV core protein and its posttranslational modification (PTM) with SUMO (small ubiquitin-like modifiers) during the establishment of cccDNA. HBV core protein SUMO PTM was analyzed in His-SUMO-overexpressing cell lines. The impact of HBV core SUMOylation on association with cellular interaction partners and on the HBV life cycle was determined using SUMOylation-deficient mutants of the HBV core protein. Here, we show that the HBV core protein is posttranslationally modified by the addition of SUMO and that this modification impacts nuclear import of rcDNA. By using SUMOylation-deficient HBV core mutants, we show that SUMO modification is a prerequisite for the association with specific promyelocytic leukemia nuclear bodies (PML-NBs) and regulates the conversion of rcDNA to cccDNA. By in vitro SUMOylation of HBV core, we obtained evidence that SUMOylation triggers nucleocapsid disassembly, providing novel insights into the nuclear import process of rcDNA. HBV core protein SUMOylation and subsequent association with PML bodies in the nucleus constitute a key step in the conversion of HBV rcDNA to cccDNA and therefore a promising target for inhibiting formation of the HBV persistence reservoir. IMPORTANCE HBV cccDNA is formed from the incomplete rcDNA involving several host DDR proteins. The exact process and the site of cccDNA formation are poorly understood. Here, we show that HBV core protein SUMO modification is a novel PTM regulating the function of HBV core. A minor specific fraction of the HBV core protein resides with PML-NBs in the nuclear matrix. SUMO modification of HBV core protein mediates its recruitment to specific PML-NBs within the host cell. Within HBV nucleocapsids, SUMOylation of HBV core induces HBV capsid disassembly and is a prerequisite for nuclear entry of HBV core. SUMO HBV core protein association with PML-NBs is crucial for efficient conversion of rcDNA to cccDNA and for the establishment of the viral persistence reservoir. HBV core protein SUMO modification and the subsequent association with PML-NBs might constitute a potential novel target in the development of drugs targeting the cccDNA.
Collapse
Affiliation(s)
- Samuel Hofmann
- Institute of Virology, School of Medicine, Technical University of Munich, Germany
- Institute of Virology, Hannover Medical School, Hannover, Germany
| | - Verena Plank
- Institute of Virology, School of Medicine, Technical University of Munich, Germany
| | - Peter Groitl
- Institute of Virology, School of Medicine, Technical University of Munich, Germany
| | - Nathalie Skvorc
- Institute of Virology, School of Medicine, Technical University of Munich, Germany
| | - Katharina Hofmann
- Institute of Virology, School of Medicine, Technical University of Munich, Germany
- Institute of Virology, Hannover Medical School, Hannover, Germany
| | - Julius Luther
- Institute of Virology, Hannover Medical School, Hannover, Germany
| | - Chunkyu Ko
- Institute of Virology, School of Medicine, Technical University of Munich, Germany
- Institute of Virology, Helmholtz Zentrum München, Munich, Germany
| | - Peter Zimmerman
- Department of Internal Medicine II/Molecular Biology, University Hospital Freiburg, Freiburg, Germany
| | - Volker Bruss
- Institute of Virology, Helmholtz Zentrum München, Munich, Germany
| | - Daniela Stadler
- Institute of Virology, School of Medicine, Technical University of Munich, Germany
- Institute of Virology, Helmholtz Zentrum München, Munich, Germany
| | | | - Shahinda Rezk
- Institute of Virology, School of Medicine, Technical University of Munich, Germany
- Medical Research Institute, Department of Molecular and Diagnostic Microbiology, Alexandria University, Alexandria, Egypt
| | - Michael Nassal
- Department of Internal Medicine II/Molecular Biology, University Hospital Freiburg, Freiburg, Germany
| | - Ulrike Protzer
- Institute of Virology, School of Medicine, Technical University of Munich, Germany
- Institute of Virology, Helmholtz Zentrum München, Munich, Germany
- German Center for Infection Research, Munich, Germany
| | - Sabrina Schreiner
- Institute of Virology, School of Medicine, Technical University of Munich, Germany
- Institute of Virology, Hannover Medical School, Hannover, Germany
- Institute of Virology, Helmholtz Zentrum München, Munich, Germany
- German Center for Infection Research, Munich, Germany
- Cluster of Excellence RESIST (Resolving Infection Susceptibility; EXC 2155), Hannover Medical School, Hannover, Germany
| |
Collapse
|
12
|
Osmani Z, Boonstra A. Recent Insights into the Role of B Cells in Chronic Hepatitis B and C Infections. Pathogens 2023; 12:815. [PMID: 37375505 DOI: 10.3390/pathogens12060815] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2023] [Revised: 05/30/2023] [Accepted: 06/07/2023] [Indexed: 06/29/2023] Open
Abstract
Chronic viral hepatitis infections, caused by the hepatitis B or C virus, are a major global health problem causing an estimated one million deaths each year. Immunological studies have classically focused on T cells, while B cells have largely been neglected. Emerging evidence, however, highlights a role for B cells in the immunopathogenesis of chronic hepatitis B and C infections. B cell responses appear to be altered across different clinical phases of chronic HBV infection and across stages of disease in chronic HCV infection. These B cell responses show signs of a more activated state with a simultaneous enrichment of phenotypically exhausted atypical memory B cells. Despite the fact that studies show an activating B cell signature in chronic viral hepatitis infection, antibody responses to HBsAg remain impaired in chronic HBV infection, and glycoprotein E2-specific neutralizing antibody responses remain delayed in the acute phase of HCV infection. At the same time, studies have reported that a subset of HBV- and HCV-specific B cells exhibit an exhausted phenotype. This may, at least in part, explain why antibody responses in chronic HBV and HCV patients are suboptimal. Here, we summarize recent findings and discuss upcoming research questions while looking forward to how new single-cell technologies could provide novel insights into the role of B cells in chronic viral hepatitis infections.
Collapse
Affiliation(s)
- Zgjim Osmani
- Department of Gastroenterology and Hepatology, Erasmus University Medical Center, 3015 GD Rotterdam, The Netherlands
| | - Andre Boonstra
- Department of Gastroenterology and Hepatology, Erasmus University Medical Center, 3015 GD Rotterdam, The Netherlands
| |
Collapse
|
13
|
Zheng Y, Yang L, Yu L, Zhu Y, Wu Y, Zhang Z, Xia T, Deng Q. Canocapavir Is a Novel Capsid Assembly Modulator Inducing a Conformational Change of the Linker Region of HBV Core Protein. Viruses 2023; 15:v15051195. [PMID: 37243280 DOI: 10.3390/v15051195] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2023] [Revised: 05/11/2023] [Accepted: 05/15/2023] [Indexed: 05/28/2023] Open
Abstract
Canocapavir is a novel antiviral agent with characteristics of core protein allosteric modulators (CpAMs) that is currently in a phase II clinical trial for treatment of hepatitis B virus (HBV) infection. Herein, we show that Canocapavir prevented the encapsidation of HBV pregenomic RNA and increased the accumulation of cytoplasmic empty capsids, presumably by targeting the hydrophobic pocket at the dimer-dimer interface of HBV core protein (HBc). Canocapavir treatment markedly reduced the egress of naked capsids, which could be reversed by Alix overexpression through a mechanism other than direct association of Alix with HBc. Moreover, Canocapavir interfered with the interaction between HBc and HBV large surface protein, resulting in diminished production of empty virions. Of particular note, Canocapavir induced a conformational change of capsids, with the C-terminus of HBc linker region fully exposed on the exterior of capsids. We posit that the allosteric effect may have great importance in the anti-HBV activity of Canocapavir, given the emerging virological significance of HBc linker region. In support of this notion, the mutation at HBc V124W typically recapitulated the conformational change of the empty capsid with aberrant cytoplasmic accumulation. Collectively, our results indicate Canocapavir as a mechanistically distinct type of CpAMs against HBV infection.
Collapse
Affiliation(s)
- Yuan Zheng
- Key Laboratory of Medical Molecular Virology (MOE/NHC/CAMS), Shanghai Frontiers Science Center of Pathogenic Microorganisms and Infection, School of Basic Medical Sciences, Fudan University, Shanghai 200032, China
- Shanghai Institute of Infectious Disease and Biosecurity, Shanghai 200032, China
| | - Le Yang
- Key Laboratory of Medical Molecular Virology (MOE/NHC/CAMS), Shanghai Frontiers Science Center of Pathogenic Microorganisms and Infection, School of Basic Medical Sciences, Fudan University, Shanghai 200032, China
- Shanghai Institute of Infectious Disease and Biosecurity, Shanghai 200032, China
| | - Lin Yu
- Key Laboratory of Medical Molecular Virology (MOE/NHC/CAMS), Shanghai Frontiers Science Center of Pathogenic Microorganisms and Infection, School of Basic Medical Sciences, Fudan University, Shanghai 200032, China
- Shanghai Institute of Infectious Disease and Biosecurity, Shanghai 200032, China
| | - Yuanfei Zhu
- Key Laboratory of Medical Molecular Virology (MOE/NHC/CAMS), Shanghai Frontiers Science Center of Pathogenic Microorganisms and Infection, School of Basic Medical Sciences, Fudan University, Shanghai 200032, China
- Shanghai Institute of Infectious Disease and Biosecurity, Shanghai 200032, China
| | - Yang Wu
- Key Laboratory of Medical Molecular Virology (MOE/NHC/CAMS), Shanghai Frontiers Science Center of Pathogenic Microorganisms and Infection, School of Basic Medical Sciences, Fudan University, Shanghai 200032, China
| | - Zhijun Zhang
- Shanghai Zhimeng Biopharma, Inc., 1976 Gaoke Middle Road, Suite A-302, Pudong District, Shanghai 201210, China
| | - Tian Xia
- Shanghai Zhimeng Biopharma, Inc., 1976 Gaoke Middle Road, Suite A-302, Pudong District, Shanghai 201210, China
| | - Qiang Deng
- Key Laboratory of Medical Molecular Virology (MOE/NHC/CAMS), Shanghai Frontiers Science Center of Pathogenic Microorganisms and Infection, School of Basic Medical Sciences, Fudan University, Shanghai 200032, China
- Shanghai Institute of Infectious Disease and Biosecurity, Shanghai 200032, China
| |
Collapse
|
14
|
Jin Y, Wang S, Xu S, Zhao S, Xu X, Poongavanam V, Menéndez-Arias L, Zhan P, Liu X. Targeting hepatitis B virus cccDNA levels: recent progress in seeking small molecule drug candidates. Drug Discov Today 2023; 28:103617. [PMID: 37196762 DOI: 10.1016/j.drudis.2023.103617] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2023] [Revised: 03/29/2023] [Accepted: 05/10/2023] [Indexed: 05/19/2023]
Abstract
Hepatitis B virus (HBV) infection is a major global health problem that puts people at high risk of death from cirrhosis and liver cancer. The presence of covalently closed circular DNA (cccDNA) in infected cells is considered to be the main obstacle to curing chronic hepatitis B. At present, the cccDNA cannot be completely eliminated by standard treatments. There is an urgent need to develop drugs or therapies that can reduce HBV cccDNA levels in infected cells. We summarize the discovery and optimization of small molecules that target cccDNA synthesis and degradation. These compounds are cccDNA synthesis inhibitors, cccDNA reducers, core protein allosteric modulators, ribonuclease H inhibitors, cccDNA transcriptional modulators, HBx inhibitors and other small molecules that reduce cccDNA levels. Teaser: HBV covalently closed circular DNA (cccDNA) can be stably maintained in infected cells for a prolonged period, and this is the fundamental reason why hepatitis B cannot be completely cured. Here, we review recent progress in the development of small molecules that can reduce cccDNA levels in infected cells.
Collapse
Affiliation(s)
- Yu Jin
- Department of Medicinal Chemistry, Key Laboratory of Chemical Biology (Ministry of Education), School of Pharmaceutical Sciences, Shandong University, 44 West Culture Road, 250012 Jinan, Shandong, PR China
| | - Shuo Wang
- Department of Medicinal Chemistry, Key Laboratory of Chemical Biology (Ministry of Education), School of Pharmaceutical Sciences, Shandong University, 44 West Culture Road, 250012 Jinan, Shandong, PR China
| | - Shujing Xu
- Department of Medicinal Chemistry, Key Laboratory of Chemical Biology (Ministry of Education), School of Pharmaceutical Sciences, Shandong University, 44 West Culture Road, 250012 Jinan, Shandong, PR China
| | - Shujie Zhao
- Department of Medicinal Chemistry, Key Laboratory of Chemical Biology (Ministry of Education), School of Pharmaceutical Sciences, Shandong University, 44 West Culture Road, 250012 Jinan, Shandong, PR China
| | - Xiangrui Xu
- Department of Medicinal Chemistry, Key Laboratory of Chemical Biology (Ministry of Education), School of Pharmaceutical Sciences, Shandong University, 44 West Culture Road, 250012 Jinan, Shandong, PR China
| | - Vasanthanathan Poongavanam
- Department of Physics, Chemistry and Pharmacy, University of Southern Denmark, Odense M, DK-5230, Denmark
| | - Luis Menéndez-Arias
- Centro de Biología Molecular 'Severo Ochoa' (Consejo Superior de Investigaciones Científicas & Universidad Autónoma de Madrid), 28049 Madrid, Spain.
| | - Peng Zhan
- Department of Medicinal Chemistry, Key Laboratory of Chemical Biology (Ministry of Education), School of Pharmaceutical Sciences, Shandong University, 44 West Culture Road, 250012 Jinan, Shandong, PR China.
| | - Xinyong Liu
- Department of Medicinal Chemistry, Key Laboratory of Chemical Biology (Ministry of Education), School of Pharmaceutical Sciences, Shandong University, 44 West Culture Road, 250012 Jinan, Shandong, PR China.
| |
Collapse
|
15
|
Göttig L, Weiß C, Stubbe M, Hanrieder L, Hofmann S, Grodziecki A, Stadler D, Carpentier A, Protzer U, Schreiner S. Apobec3A Deamination Functions Are Involved in Antagonizing Efficient Human Adenovirus Replication and Gene Expression. mBio 2023:e0347822. [PMID: 37154747 DOI: 10.1128/mbio.03478-22] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/10/2023] Open
Abstract
Apobec3A is involved in the antiviral host defense, targeting nuclear DNA, introducing point mutations, and thereby activating DNA damage response (DDR). Here, we found a significant upregulation of Apobec3A during HAdV infection, including Apobec3A protein stabilization mediated by the viral proteins E1B-55K and E4orf6, which subsequently limited HAdV replication and most likely involved a deaminase-dependent mechanism. The transient silencing of Apobec3A enhanced adenoviral replication. HAdV triggered Apobec3A dimer formation and enhanced activity to repress the virus. Apobec3A decreased E2A SUMOylation and interfered with viral replication centers. A comparative sequence analysis revealed that HAdV types A, C, and F may have evolved a strategy to escape Apobec3A-mediated deamination via reduced frequencies of TC dinucleotides within the viral genome. Although viral components induce major changes within infected cells to support lytic life cycles, our findings demonstrate that host Apobec3A-mediated restriction limits virus replication, albeit that HAdV may have evolved to escape this restriction. This allows for novel insights into the HAdV/host-cell interplay, which broaden the current view of how a host cell can limit HAdV infection. IMPORTANCE Our data provide a novel conceptual insight into the virus/host-cell interplay, changing the current view of how a host-cell can defeat a virus infection. Thus, our study reveals a novel and general impact of cellular Apobec3A on the intervention of human adenovirus (HAdV) gene expression and replication by improving the host antiviral defense mechanisms, thereby providing a novel basis for innovative antiviral strategies in future therapeutic settings. Ongoing investigations of the cellular pathways that are modulated by HAdV are of great interest, particularly since adenovirus-based vectors actually serve as COVID vaccine vectors and also frequently serve as tools in human gene therapy and oncolytic treatment options. HAdV constitute an ideal model system by which to analyze the transforming capabilities of DNA tumor viruses as well as the underlying molecular principles of virus-induced and cellular tumorigenesis.
Collapse
Affiliation(s)
- Lilian Göttig
- Institute of Virology, School of Medicine, Technical University of Munich, Munich, Germany
| | - Christina Weiß
- Institute of Virology, School of Medicine, Technical University of Munich, Munich, Germany
| | - Miona Stubbe
- Institute of Virology, School of Medicine, Technical University of Munich, Munich, Germany
| | - Lisa Hanrieder
- Institute of Virology, School of Medicine, Technical University of Munich, Munich, Germany
- Institute of Virology, Hannover Medical School, Hannover, Germany
- German Center for Infection Research (DZIF), Munich, Germany
| | - Samuel Hofmann
- Institute of Virology, School of Medicine, Technical University of Munich, Munich, Germany
- Institute of Virology, Hannover Medical School, Hannover, Germany
- Cluster of Excellence RESIST (Resolving Infection Susceptibility; EXC 2155), Hannover Medical School, Hannover, Germany
| | - Alessandro Grodziecki
- Institute of Virology, Hannover Medical School, Hannover, Germany
- Cluster of Excellence RESIST (Resolving Infection Susceptibility; EXC 2155), Hannover Medical School, Hannover, Germany
| | - Daniela Stadler
- Institute of Virology, School of Medicine, Technical University of Munich, Munich, Germany
| | | | - Ulrike Protzer
- Institute of Virology, School of Medicine, Technical University of Munich, Munich, Germany
- German Center for Infection Research (DZIF), Munich, Germany
- Institute of Virology, Helmholtz Zentrum München, Munich, Germany
| | - Sabrina Schreiner
- Institute of Virology, School of Medicine, Technical University of Munich, Munich, Germany
- Institute of Virology, Hannover Medical School, Hannover, Germany
- German Center for Infection Research (DZIF), Munich, Germany
- Cluster of Excellence RESIST (Resolving Infection Susceptibility; EXC 2155), Hannover Medical School, Hannover, Germany
- Institute of Virology, Helmholtz Zentrum München, Munich, Germany
| |
Collapse
|
16
|
Bahrulolum H, Tarrahimofrad H, Rouzbahani FN, Nooraei S, Sameh MM, Hajizade A, Ahmadian G. Potential of CRISPR/Cas system as emerging tools in the detection of viral hepatitis infection. Virol J 2023; 20:91. [PMID: 37158910 PMCID: PMC10165583 DOI: 10.1186/s12985-023-02048-5] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2023] [Accepted: 04/23/2023] [Indexed: 05/10/2023] Open
Abstract
Viral hepatitis, the most common cause of inflammatory liver disease, affects hundreds of millions of people worldwide. It is most commonly associated with one of the five nominal hepatitis viruses (hepatitis A-E viruses). HBV and HCV can cause acute infections and lifelong, persistent chronic infections, while HAV and HEV cause self-limiting acute infections. HAV and HEV are predominantly transmitted through the fecal-oral route, while diseases transmitted by the other forms are blood-borne diseases. Despite the success in the treatment of viral hepatitis and the development of HAV and HBV vaccines, there is still no accurate diagnosis at the genetic level for these diseases. Timely diagnosis of viral hepatitis is a prerequisite for efficient therapeutic intervention. Due to the specificity and sensitivity of clustered regularly interspaced short palindromic repeat (CRISPR)/CRISPR-associated sequences (Cas) technology, it has the potential to meet critical needs in the field of diagnosis of viral diseases and can be used in versatile point-of-care (POC) diagnostic applications to detect viruses with both DNA and RNA genomes. In this review, we discuss recent advances in CRISPR-Cas diagnostics tools and assess their potential and prospects in rapid and effective strategies for the diagnosis and control of viral hepatitis infection.
Collapse
Affiliation(s)
- Howra Bahrulolum
- Department of Industrial and Environmental and Biotechnology, National Institute of Genetic Engineering and Biotechnology (NIGEB), Tehran, 1497716316 Iran
| | - Hossein Tarrahimofrad
- Department of Animal Biotechnology, National Institute of Genetic Engineering and Biotechnology (NIGEB), Tehran, 1497716316 Iran
| | - Fatemeh Nouri Rouzbahani
- Department of Industrial and Environmental and Biotechnology, National Institute of Genetic Engineering and Biotechnology (NIGEB), Tehran, 1497716316 Iran
| | - Saghi Nooraei
- Department of Industrial and Environmental and Biotechnology, National Institute of Genetic Engineering and Biotechnology (NIGEB), Tehran, 1497716316 Iran
| | - Mehdi Mousavi Sameh
- Department of Industrial and Environmental and Biotechnology, National Institute of Genetic Engineering and Biotechnology (NIGEB), Tehran, 1497716316 Iran
| | - Abbas Hajizade
- Applied Microbiology Research Center, Systems Biology and Poisonings Institute, Baqiyatallah University of Medical Sciences, Tehran, 1435916471 Iran
| | - Gholamreza Ahmadian
- Department of Industrial and Environmental and Biotechnology, National Institute of Genetic Engineering and Biotechnology (NIGEB), Tehran, 1497716316 Iran
| |
Collapse
|
17
|
Bhat S, Ahanger IA, Kazim SN. Forthcoming Developments in Models to Study the Hepatitis B Virus Replication Cycle, Pathogenesis, and Pharmacological Advancements. ACS OMEGA 2023; 8:14273-14289. [PMID: 37125123 PMCID: PMC10134252 DOI: 10.1021/acsomega.2c07154] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/06/2022] [Accepted: 02/08/2023] [Indexed: 05/03/2023]
Abstract
Hepatitis, liver cirrhosis, and hepatocellular carcinoma are all manifestations of chronic hepatitis B. Its pathogenesis and molecular mechanism remain mysterious. As medical science progresses, different models are being used to study the disease from the physiological and molecular levels. Animal models have played an unprecedented role in achieving in-depth knowledge of the disease while posing no risk of harming humans throughout the study. The scarcity of acceptable animal models has slowed progress in hepatitis B virus (HBV) research and preclinical testing of antiviral medicines since HBV has a narrow species tropism and exclusively infects humans and higher primates. The development of human chimeric mice was supported by a better understanding of the obstacles to interspecies transmission, which has substantially opened the way for HBV research in vivo and the evaluation of possible chronic hepatitis B therapeutics. Animal models are cumbersome to handle, not accessible, and expensive. Hence, it is herculean to investigate the HBV replication cycle in animal models. Therefore, it becomes essential to build a splendid in vitro cell culture system to demonstrate the mechanisms attained by the HBV for its multiplication and sustenance. We also addressed the advantages and caveats associated with different models in examining HBV.
Collapse
Affiliation(s)
- Sajad
Ahmad Bhat
- Centre
for Interdisciplinary Research in Basic Sciences, Jamia Millia Islamia, New Delhi, India
| | - Ishfaq Ahmad Ahanger
- Centre
for Interdisciplinary Research in Basic Sciences, Jamia Millia Islamia, New Delhi, India
- Clinical
Biochemistry University of Kashmir, Srinagar, India
| | - Syed Naqui Kazim
- Centre
for Interdisciplinary Research in Basic Sciences, Jamia Millia Islamia, New Delhi, India
- Phone: +91 9953621758.
| |
Collapse
|
18
|
Romero S, Unchwaniwala N, Evans EL, Eliceiri KW, Loeb DD, Sherer NM. Live Cell Imaging Reveals HBV Capsid Translocation from the Nucleus To the Cytoplasm Enabled by Cell Division. mBio 2023; 14:e0330322. [PMID: 36809075 PMCID: PMC10127671 DOI: 10.1128/mbio.03303-22] [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: 11/29/2022] [Accepted: 01/17/2023] [Indexed: 02/23/2023] Open
Abstract
Hepatitis B virus (HBV) capsid assembly is traditionally thought to occur predominantly in the cytoplasm, where the virus gains access to the virion egress pathway. To better define sites of HBV capsid assembly, we carried out single cell imaging of HBV Core protein (Cp) subcellular trafficking over time under conditions supporting genome packaging and reverse transcription in Huh7 hepatocellular carcinoma cells. Time-course analyses including live cell imaging of fluorescently tagged Cp derivatives showed Cp to accumulate in the nucleus at early time points (~24 h), followed by a marked re-distribution to the cytoplasm at 48 to 72 h. Nucleus-associated Cp was confirmed to be capsid and/or high-order assemblages using a novel dual label immunofluorescence strategy. Nuclear-to-cytoplasmic re-localization of Cp occurred predominantly during nuclear envelope breakdown in conjunction with cell division, followed by strong cytoplasmic retention of Cp. Blocking cell division resulted in strong nuclear entrapment of high-order assemblages. A Cp mutant, Cp-V124W, predicted to exhibit enhanced assembly kinetics, also first trafficked to the nucleus to accumulate at nucleoli, consistent with the hypothesis that Cp's transit to the nucleus is a strong and constitutive process. Taken together, these results provide support for the nucleus as an early-stage site of HBV capsid assembly, and provide the first dynamic evidence of cytoplasmic retention after cell division as a mechanism underpinning capsid nucleus-to-cytoplasm relocalization. IMPORTANCE Hepatitis B virus (HBV) is an enveloped, reverse-transcribing DNA virus that is a major cause of liver disease and hepatocellular carcinoma. Subcellular trafficking events underpinning HBV capsid assembly and virion egress remain poorly characterized. Here, we developed a combination of fixed and long-term (>24 h) live cell imaging technologies to study the single cell trafficking dynamics of the HBV Core Protein (Cp). We demonstrate that Cp first accumulates in the nucleus, and forms high-order structures consistent with capsids, with the predominant route of nuclear egress being relocalization to the cytoplasm during cell division in conjunction with nuclear membrane breakdown. Single cell video microscopy demonstrated unequivocally that Cp's localization to the nucleus is constitutive. This study represents a pioneering application of live cell imaging to study HBV subcellular transport, and demonstrates links between HBV Cp and the cell cycle.
Collapse
Affiliation(s)
- Sofia Romero
- McArdle Laboratory for Cancer Research (Department of Oncology), University of Wisconsin-Madison School of Medicine and Public Health, Madison, Wisconsin, USA
- Institute for Molecular Virology, University of Wisconsin-Madison, Madison, Wisconsin, USA
- Microbiology Doctoral Training Program, University of Wisconsin-Madison, Madison, Wisconsin, USA
- Carbone Cancer Center, University of Wisconsin-Madison School of Medicine and Public Health, Madison, Wisconsin, USA
| | - Nuruddin Unchwaniwala
- McArdle Laboratory for Cancer Research (Department of Oncology), University of Wisconsin-Madison School of Medicine and Public Health, Madison, Wisconsin, USA
- Institute for Molecular Virology, University of Wisconsin-Madison, Madison, Wisconsin, USA
- Carbone Cancer Center, University of Wisconsin-Madison School of Medicine and Public Health, Madison, Wisconsin, USA
| | - Edward L. Evans
- Laboratory for Optical and Computational Instrumentation, Center for Quantitative Cell Imaging, University of Wisconsin-Madison, Madison, Wisconsin, USA
- Morgridge Institute for Research, Madison, Wisconsin, USA
| | - Kevin W. Eliceiri
- Laboratory for Optical and Computational Instrumentation, Center for Quantitative Cell Imaging, University of Wisconsin-Madison, Madison, Wisconsin, USA
- Morgridge Institute for Research, Madison, Wisconsin, USA
| | - Daniel D. Loeb
- McArdle Laboratory for Cancer Research (Department of Oncology), University of Wisconsin-Madison School of Medicine and Public Health, Madison, Wisconsin, USA
- Carbone Cancer Center, University of Wisconsin-Madison School of Medicine and Public Health, Madison, Wisconsin, USA
| | - Nathan M. Sherer
- McArdle Laboratory for Cancer Research (Department of Oncology), University of Wisconsin-Madison School of Medicine and Public Health, Madison, Wisconsin, USA
- Institute for Molecular Virology, University of Wisconsin-Madison, Madison, Wisconsin, USA
- Carbone Cancer Center, University of Wisconsin-Madison School of Medicine and Public Health, Madison, Wisconsin, USA
| |
Collapse
|
19
|
Bello KE, Mat Jusoh TNA, Irekeola AA, Abu N, Mohd Amin NAZ, Mustaffa N, Shueb RH. A Recent Prevalence of Hepatitis B Virus (HBV) Genotypes and Subtypes in Asia: A Systematic Review and Meta-Analysis. Healthcare (Basel) 2023; 11:healthcare11071011. [PMID: 37046937 PMCID: PMC10094200 DOI: 10.3390/healthcare11071011] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2023] [Revised: 03/24/2023] [Accepted: 03/27/2023] [Indexed: 04/05/2023] Open
Abstract
Background and Aim: Despite introducing the hepatitis B virus (HBV) vaccine, the incidence of the Hepatitis B virus globally is still a major health concern. This systematic review and meta-analysis were conducted to provide detailed information on the prevalence of HBV genotypes and subtypes in circulation in Asia. Methods: A systematic search for articles describing the prevalence of HBV genotypes and subtypes in Asia was conducted following the Preferred Reporting Items for Systematic Reviews and Meta-analysis (PRISMA) guidelines. Results: Our search returned 207 eligible articles involving 49,279 genotypes and 7457 subtypes representing 28 Asian countries. A meta-analysis was performed on our eligible studies using the Random effect Model. The pooled prevalence of HBV genotypes showed that genotype C (30.9%) (95% CI, 27.5–34.5%; I2 = 97.57%; p < 0.001) was the most common HBV genotype in Asia, followed by genotype B (17.8%) (95% CI, 15.5–20.4%; I2 = 97.26%; p < 0.001) and genotype D (15.4%) (95% CI, 11.8–19.8%). Vietnam had the highest prevalence of genotype B, Lebanon had the highest prevalence of genotypes C, and Jordan had the highest prevalence of genotype D. There was variation in genotypic prevalence with respect to the target genes for HBV genotyping. Reverse dot blot hybridization had the highest estimate of genotypes B and C. HBV subtype C2 (40.0%) (95% CI, 33.3–47.0) is the most prevalent HBV subtype. Conclusion: Evidence from this study reveals that HBV genotypes C and B are the most dominant HBV genotypes in Asia, and HBV subtype C2 is more endemic in Asia.
Collapse
Affiliation(s)
- Kizito Eneye Bello
- Department of Medical Microbiology and Parasitology, School of Medical Sciences, Universiti Sains Malaysia, Health Campus, Kubang Kerian 16150, Kelantan, Malaysia
- Department of Microbiology, Faculty of Natural Science, Kogi State University (Prince Abubakar Audu University), Anyigba 1008, Kogi State, Nigeria
| | - Tuan Nur Akmalina Mat Jusoh
- Department of Medical Microbiology and Parasitology, School of Medical Sciences, Universiti Sains Malaysia, Health Campus, Kubang Kerian 16150, Kelantan, Malaysia
| | - Ahmad Adebayo Irekeola
- Department of Medical Microbiology and Parasitology, School of Medical Sciences, Universiti Sains Malaysia, Health Campus, Kubang Kerian 16150, Kelantan, Malaysia
- Microbiology Unit, Department of Biological Sciences, College of Natural and Applied Sciences, Summit University Offa, Offa 4412, Kwara State, Nigeria
| | - Norhidayah Abu
- Department of Medical Microbiology and Parasitology, School of Medical Sciences, Universiti Sains Malaysia, Health Campus, Kubang Kerian 16150, Kelantan, Malaysia
- Advanced Materials Research Centre (A.M.R.E.C.), Lot 34 Jalan Hi-Tech 2/3, Kulim Hi-Tech Park, Kulim 09000, Kedah, Malaysia
| | - Nur Amalin Zahirah Mohd Amin
- Department of Medical Microbiology and Parasitology, School of Medical Sciences, Universiti Sains Malaysia, Health Campus, Kubang Kerian 16150, Kelantan, Malaysia
| | - Nazri Mustaffa
- Department of Medicine, School of Medical Sciences, Universiti Sains Malaysia, Health Campus, Kubang Kerian 16150, Kelantan, Malaysia
- Hospital Universiti Sains Malaysia, Kubang Kerian 16150, Kelantan, Malaysia
| | - Rafidah Hanim Shueb
- Department of Medical Microbiology and Parasitology, School of Medical Sciences, Universiti Sains Malaysia, Health Campus, Kubang Kerian 16150, Kelantan, Malaysia
- Institute for Research in Molecular Medicine (I.N.F.O.R.M.M.), Universiti Sains Malaysia, Kubang Kerian 16150, Kelantan, Malaysia
| |
Collapse
|
20
|
Yang H, Yao W, Yang J. Overview of the development of HBV small molecule inhibitors. Eur J Med Chem 2023; 249:115128. [PMID: 36709647 DOI: 10.1016/j.ejmech.2023.115128] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2022] [Revised: 01/13/2023] [Accepted: 01/15/2023] [Indexed: 01/28/2023]
Abstract
Like tuberculosis and Acquired Immune Deficiency Syndrome (AIDS), hepatitis B is a globally recognized major public health threat. Although there are many small-molecule drugs for the treatment of hepatitis B, the approved drugs cannot eradicate the pathogenic culprit covalently closed circular DNA in patients, so the patients need long-term medication to control HBV amplification. Driven by a high unmet medical need, many pharmaceutical companies and research institutions have been engaged in the development of anti-HBV drugs to achieve a functional cure for chronic hepatitis B as soon as possible. This review summarizes the pathogenesis of hepatitis B virus and the research progress in the development of anti-HBV small molecule drugs, and introduces the cccDNA formation and transcription inhibitors and core inhibitors in detail, especially emphasizes the role of chinese herbal medicine in the treatment of chronic hepatitis B. Furthermore, this review proposes three potential strategies for cccDNA eradication in the future. We believe this review will provide meaningful guidance to achieve a functional cure for viral hepatitis B in the future.
Collapse
Affiliation(s)
- Huihui Yang
- School of Health and Life Sciences, University of Health and Rehabilitation Sciences, Qingdao, 266001, China
| | - Weiwei Yao
- School of Health and Life Sciences, University of Health and Rehabilitation Sciences, Qingdao, 266001, China
| | - Jinfei Yang
- School of Health and Life Sciences, University of Health and Rehabilitation Sciences, Qingdao, 266001, China.
| |
Collapse
|
21
|
The scientific basis of combination therapy for chronic hepatitis B functional cure. Nat Rev Gastroenterol Hepatol 2023; 20:238-253. [PMID: 36631717 DOI: 10.1038/s41575-022-00724-5] [Citation(s) in RCA: 40] [Impact Index Per Article: 40.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 11/24/2022] [Indexed: 01/13/2023]
Abstract
Functional cure of chronic hepatitis B (CHB) - or hepatitis B surface antigen (HBsAg) loss after 24 weeks off therapy - is now the goal of treatment, but is rarely achieved with current therapy. Understanding the hepatitis B virus (HBV) life cycle and immunological defects that lead to persistence can identify targets for novel therapy. Broadly, treatments fall into three categories: those that reduce viral replication, those that reduce antigen load and immunotherapies. Profound viral suppression alone does not achieve quantitative (q)HBsAg reduction or HBsAg loss. Combining nucleos(t)ide analogues and immunotherapy reduces qHBsAg levels and induces HBsAg loss in some patients, particularly those with low baseline qHBsAg levels. Even agents that are specifically designed to reduce viral antigen load might not be able to achieve sustained HBsAg loss when used alone. Thus, rationale exists for the use of combinations of all three therapy types. Monitoring during therapy is important not just to predict HBsAg loss but also to understand mechanisms of HBsAg loss using viral and immunological biomarkers, and in selected cases intrahepatic sampling. We consider various paths to functional cure of CHB and the need to individualize treatment of this heterogeneous infection until a therapeutic avenue for all patients with CHB is available.
Collapse
|
22
|
Yan R, Cai D, Zong Y, Guo L, Zhou Y, Tang A, Li L, Huang Q, Colonno R, Walker MA. Preclinical characterization of ABI-H2158, an HBV core inhibitor with dual mechanisms of action. Antiviral Res 2023; 209:105485. [PMID: 36509208 DOI: 10.1016/j.antiviral.2022.105485] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2022] [Revised: 11/21/2022] [Accepted: 12/08/2022] [Indexed: 12/13/2022]
Abstract
The HBV core protein plays an integral role in multiple steps of the HBV lifecycle. Consequently, HBV core inhibitors interrupt multiple steps of the replication cycle, including blocking pgRNA encapsidation and prematurely disassembling existing nucleocapsids, thereby preventing them from transporting relaxed circular (rcDNA) to the nucleus for conversion to covalently closed circular DNA (cccDNA). ABI-H2158 is an HBV core inhibitor that advanced into Phase 2 clinical trials for the treatment of chronic hepatitis B virus infection (cHBV) but was discontinued due to hepatotoxicity. Here, the potency, selectivity, and mechanisms of action of ABI-H2158 were evaluated using a variety of cell-based assays. Antiviral activity was measured by quantifying intracellular or secreted HBV DNA, RNA, and antigens. ABI-H2158 inhibited HBV replication by blocking pgRNA encapsidation in induced HepAD38 cells (EC50 = 22 nM) and had similar potency in HBV-infected HepG2-NTCP cells (EC50 = 27 nM) and primary human hepatocytes (PHH) (EC50 = 41 nM). ABI-H2158 is a pan-genotypic HBV inhibitor, with EC50s ranging from 7.1 to 22 nM across HBV genotypes A-E. ABI-H2158 also potently blocked the formation of cccDNA in de novo HBV infections with EC50s of ∼200 nM in HepG2-NTCP and PHH assays. These results indicate ABI-H2158 has dual mechanisms of action, inhibiting both early and late steps of the HBV replication cycle.
Collapse
Affiliation(s)
- Ran Yan
- Assembly Biosciences, South San Francisco, CA, USA.
| | - Dawei Cai
- Assembly Biosciences, South San Francisco, CA, USA
| | - Yuhua Zong
- Assembly Biosciences, South San Francisco, CA, USA
| | - Lida Guo
- Assembly Biosciences, South San Francisco, CA, USA
| | - Yi Zhou
- Assembly Biosciences, South San Francisco, CA, USA
| | - Ariel Tang
- Assembly Biosciences, South San Francisco, CA, USA
| | - Lichun Li
- Assembly Biosciences, South San Francisco, CA, USA
| | - Qi Huang
- Assembly Biosciences, South San Francisco, CA, USA
| | | | | |
Collapse
|
23
|
Yan R, Cai D, Ouyang L, Colonno R, Huang Q, Kitrinos KM. Development of a sensitive, multi-assay platform to monitor low levels of HBV DNA and pgRNA in patients with chronic hepatitis B virus infection. J Virol Methods 2023; 311:114640. [PMID: 36332714 DOI: 10.1016/j.jviromet.2022.114640] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2022] [Revised: 10/22/2022] [Accepted: 10/29/2022] [Indexed: 11/06/2022]
Abstract
HBV cure rates remain low despite prolonged nucleos(t)ide (NrtI) therapy, likely due to persistent residual viral replication and an inability to eliminate covalently closed circular DNA (cccDNA). Therapies with novel mechanisms of action against hepatitis B virus (HBV) are being explored with the goal of achieving sustained off-treatment response and a functional cure without requiring lifelong therapy. Recent studies have indicated that serum HBV DNA levels (a biomarker for viral replication) combined with serum pregenomic RNA (pgRNA) levels (a surrogate for intrahepatic cccDNA transcriptional activity), may provide a better prediction for the risk of liver-related complications. Current HBV DNA assays, such as the COBAS AmpliPrep/COBAS TaqMan HBV test v2.0, quantitate HBV DNA down to 20 IU/mL, but are not able to monitor loss of residual virus in patients on NrtI therapy. There are no commercially available assays approved to detect serum/plasma HBV pgRNA levels. We have developed a multi-assay panel of highly sensitive nucleic acid assays designed to monitor levels of HBV DNA, pgRNA and total nucleic acids (TNA, composite DNA + pgRNA) in clinical specimens and to monitor changes during treatment with new antiviral combination regimens.
Collapse
Affiliation(s)
- Ran Yan
- Assembly Biosciences, South San Francisco, CA, USA.
| | - Dawei Cai
- Assembly Biosciences, South San Francisco, CA, USA
| | - Lea Ouyang
- Assembly Biosciences, South San Francisco, CA, USA
| | | | - Qi Huang
- Assembly Biosciences, South San Francisco, CA, USA
| | | |
Collapse
|
24
|
Tajwar R, Bradley DP, Ponzar NL, Tavis JE. Predicted structure of the hepatitis B virus polymerase reveals an ancient conserved protein fold. Protein Sci 2022; 31:e4421. [PMID: 36173165 PMCID: PMC9601786 DOI: 10.1002/pro.4421] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2022] [Revised: 07/31/2022] [Accepted: 08/02/2022] [Indexed: 11/12/2022]
Abstract
Hepatitis B virus (HBV) chronically infects >250 million people. It replicates by a unique protein-primed reverse transcription mechanism, and the primary anti-HBV drugs are nucleos(t)ide analogs targeting the viral polymerase (P). P has four domains compared to only two in most reverse transcriptases: the terminal protein (TP) that primes DNA synthesis, a spacer, the reverse transcriptase (RT), and the ribonuclease H (RNase H). Despite being a major drug target and catalyzing a reverse transcription pathway very different from the retroviruses, HBV P has resisted structural analysis for decades. Here, we exploited computational advances to model P. The TP wrapped around the RT domain rather than forming the anticipated globular domain, with the priming tyrosine poised over the RT active site. The orientation of the RT and RNase H domains resembled that of the retroviral enzymes despite the lack of sequences analogous to the retroviral linker region. The model was validated by mapping residues with known surface exposures, docking nucleic acids, mechanistically interpreting mutations with strong phenotypes, and docking inhibitors into the RT and RNase H active sites. The HBV P fold, including the orientation of the TP domain, was conserved among hepadnaviruses infecting rodent to fish hosts and a nackednavirus, but not in other non-retroviral RTs. Therefore, this protein fold has persisted since the hepadnaviruses diverged from nackednaviruses >400 million years ago. This model will advance mechanistic analyses into the poorly understood enzymology of HBV reverse transcription and will enable drug development against non-active site targets for the first time.
Collapse
Affiliation(s)
- Razia Tajwar
- Department of Molecular Microbiology and Immunology, School of Medicine and Institute for Drug and Biotherapeutic InnovationSaint Louis UniversitySaint LouisMissouriUSA
| | - Daniel P. Bradley
- Department of Molecular Microbiology and Immunology, School of Medicine and Institute for Drug and Biotherapeutic InnovationSaint Louis UniversitySaint LouisMissouriUSA
| | - Nathan L. Ponzar
- Department of Molecular Microbiology and Immunology, School of Medicine and Institute for Drug and Biotherapeutic InnovationSaint Louis UniversitySaint LouisMissouriUSA
| | - John E. Tavis
- Department of Molecular Microbiology and Immunology, School of Medicine and Institute for Drug and Biotherapeutic InnovationSaint Louis UniversitySaint LouisMissouriUSA
| |
Collapse
|
25
|
Goto A, Rodriguez-Esteban R, Scharf SH, Morris GM. Understanding the genetics of viral drug resistance by integrating clinical data and mining of the scientific literature. Sci Rep 2022; 12:14476. [PMID: 36008431 PMCID: PMC9403226 DOI: 10.1038/s41598-022-17746-3] [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: 12/15/2021] [Accepted: 07/30/2022] [Indexed: 11/16/2022] Open
Abstract
Drug resistance caused by mutations is a public health threat for existing and emerging viral diseases. A wealth of evidence about these mutations and their clinically associated phenotypes is scattered across the literature, but a comprehensive perspective is usually lacking. This work aimed to produce a clinically relevant view for the case of Hepatitis B virus (HBV) mutations by combining a chronic HBV clinical study with a compendium of genetic mutations systematically gathered from the scientific literature. We enriched clinical mutation data by systematically mining 2,472,725 scientific articles from PubMed Central in order to gather information about the HBV mutational landscape. By performing this analysis, we were able to identify mutational hotspots for each HBV genotype (A-E) and gene (C, X, P, S), as well as the location of disulfide bonds associated with these mutations. Through a modelling study, we also identified a mutation position common in both the clinical data and the literature that is located at the binding pocket for a known anti-HBV drug, namely entecavir. The results of this novel approach show the potential of integrated analyses to assist in the development of new drugs for viral diseases that are more robust to resistance. Such analyses should be of particular interest due to the increasing importance of viral resistance in established and emerging viruses, such as for newly developed drugs against SARS-CoV-2.
Collapse
Affiliation(s)
- An Goto
- Oxford Protein Informatics Group, Department of Statistics, University of Oxford, 24-29 St Giles', Oxford, OX1 3LB, UK
| | | | | | - Garrett M Morris
- Oxford Protein Informatics Group, Department of Statistics, University of Oxford, 24-29 St Giles', Oxford, OX1 3LB, UK.
| |
Collapse
|
26
|
Mersinoglu B, Cristinelli S, Ciuffi A. The Impact of Epitranscriptomics on Antiviral Innate Immunity. Viruses 2022; 14:v14081666. [PMID: 36016289 PMCID: PMC9412694 DOI: 10.3390/v14081666] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2022] [Revised: 07/21/2022] [Accepted: 07/25/2022] [Indexed: 11/18/2022] Open
Abstract
Epitranscriptomics, i.e., chemical modifications of RNA molecules, has proven to be a new layer of modulation and regulation of protein expression, asking for the revisiting of some aspects of cellular biology. At the virological level, epitranscriptomics can thus directly impact the viral life cycle itself, acting on viral or cellular proteins promoting replication, or impacting the innate antiviral response of the host cell, the latter being the focus of the present review.
Collapse
|
27
|
Bhat S, Kazim SN. HBV cccDNA-A Culprit and Stumbling Block for the Hepatitis B Virus Infection: Its Presence in Hepatocytes Perplexed the Possible Mission for a Functional Cure. ACS OMEGA 2022; 7:24066-24081. [PMID: 35874215 PMCID: PMC9301636 DOI: 10.1021/acsomega.2c02216] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/17/2023]
Abstract
Hepatitis B virus infection (HBV) is still a big health problem across the globe. It has been linked to the development of liver cirrhosis and hepatocellular carcinoma and can trigger different types of liver damage. Existing medicines are unable to disable covalently closed circular DNA (cccDNA), which may result in HBV persistence and recurrence. The current therapeutic goal is to achieve a functional cure, which means HBV-DNA no longer exists when treatment stops and the absence of HBsAg seroclearance. However, due to the presence of integrated HBV DNA and cccDNA functional treatment is now regarded to be difficult. In order to uncover pathways for potential therapeutic targets and identify medicines that could result in large rates of functional cure, a thorough understanding of the virus' biology is required. The proteins of the virus and episomal cccDNA are thought to be critical for the management and support of the HBV replication cycle as they interact directly with the host proteome to establish the best atmosphere for the virus while evading immune detection. The breakthroughs of host dependence factors, cccDNA transcription, epigenetic regulation, and immune-mediated breakdown have all produced significant progress in our understanding of cccDNA biology during the past decade. There are some strategies where cccDNA can be targeted either in a direct or indirect way and are presently at the point of discovery or preclinical or early clinical advancement. Editing of genomes, techniques targeting host dependence factors or epigenetic gene maintenance, nucleocapsid modulators, miRNA, siRNA, virion secretory inhibitors, and immune-mediated degradation are only a few examples. Though cccDNA approaches for direct targeting are still in the early stages of development, the assembly of capsid modulators and immune-reliant treatments have made it to the clinic. Clinical trials are currently being conducted to determine their efficiency and safety in patients, as well as their effect on viral cccDNA. The influence of recent breakthroughs in the development of new treatment techniques on cccDNA biology is also summarized in this review.
Collapse
Affiliation(s)
- Sajad
Ahmad Bhat
- Jamia Millia Islamia Central University, Centre for Interdisciplinary Research in Basic Sciences, New Delhi 110025, India
| | - Syed Naqui Kazim
- Jamia Millia Islamia Central University, Centre for Interdisciplinary Research in Basic Sciences, New Delhi 110025, India
| |
Collapse
|
28
|
Shaha M, Majumder S, Hossain MS, Jahan M, Rahmat R, Asma R, Islam MA, Rahman MH, Das KC, Sarker PK, Mahtab MA, Akbar SMF, Salimullah M. Identification of a novel variant of hepatitis B virus isolated from patient co-infected with hepatitis C virus. Virus Res 2022; 319:198859. [PMID: 35809696 DOI: 10.1016/j.virusres.2022.198859] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2022] [Revised: 07/05/2022] [Accepted: 07/05/2022] [Indexed: 11/16/2022]
Abstract
Hepatitis B virus (HBV) is a major public health concern worldwide. Co-infection of hepatitis B patients with other pathogens intensifies the severity of the disease. We report a novel variant of hepatitis B virus (HBV) in Bangladesh isolated from a patient co-infected with hepatitis C virus (HCV) who exhibited liver cirrhosis. From 150 collected plasma samples, we sequenced HBV complete genome from one HBV-HCV co-infected patient. The complete genome was analysed using bioinformatics tools, NCBI BLAST, Geno2Pheno, and SnapGene software. The strain belongs to genotype A and subgenotype A1. Upon analysing the complete genome of this strain, we found a frameshift deletion of 54 nucleotides at the pre-S2 region, a functional regulator of HBV surface protein. Furthermore, we observed a Y126H mutation in the polymerase protein of this strain. This is the first report with such an unusual pre-S deletion event of the HBV genome in an HCV-co-infected patient associated with liver cirrhosis. These findings may inform scientists about genomic modifications in the HBV genome associated with HCV co-infection.
Collapse
Affiliation(s)
- Modhusudon Shaha
- Microbial Biotechnology Division, National Institute of Biotechnology, Savar, Dhaka 1349, Bangladesh; Department of Biochemistry and Molecular Biology, Biomedicine Discovery Institute, Monash University, Clayton, Victoria 3800, Australia
| | - Sumen Majumder
- Microbial Biotechnology Division, National Institute of Biotechnology, Savar, Dhaka 1349, Bangladesh; Department of Microbiology, Jagannath University, Dhaka 1000, Bangladesh
| | - Md Saddam Hossain
- Microbial Biotechnology Division, National Institute of Biotechnology, Savar, Dhaka 1349, Bangladesh
| | - Munira Jahan
- Department of Virology, Bangabandhu Sheikh Mujib Medical University Hospital, Dhaka 1000, Bangladesh
| | - Raad Rahmat
- Department of Mathematics and Natural Sciences, School of Data and Sciences, BRAC University, Mohakhali, Dhaka 1212, Bangladesh
| | - Ridwana Asma
- Department of Virology, Bangabandhu Sheikh Mujib Medical University Hospital, Dhaka 1000, Bangladesh
| | | | - Md Hadisur Rahman
- Molecular Biotechnology Division, National Institute of Biotechnology, Savar, Dhaka 1349, Bangladesh
| | - Keshob Chandra Das
- Molecular Biotechnology Division, National Institute of Biotechnology, Savar, Dhaka 1349, Bangladesh
| | - Palash Kumar Sarker
- Microbial Biotechnology Division, National Institute of Biotechnology, Savar, Dhaka 1349, Bangladesh
| | - Mamun Al Mahtab
- Department of Hepatology, Bangabandhu Sheikh Mujib Medical University Hospital, Dhaka 1000, Bangladesh
| | | | - Md Salimullah
- Molecular Biotechnology Division, National Institute of Biotechnology, Savar, Dhaka 1349, Bangladesh.
| |
Collapse
|
29
|
Liver biopsy of chronic hepatitis B patients indicates HBV integration profile may complicate the endpoint and effect of entecavir treatment. Antiviral Res 2022; 204:105363. [PMID: 35709897 DOI: 10.1016/j.antiviral.2022.105363] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2022] [Revised: 06/01/2022] [Accepted: 06/09/2022] [Indexed: 11/23/2022]
Abstract
AIMS Viral integration profiles attract increased interest in the study of HBV-related hepatocellular carcinoma (HCC), but their features in the early stage of infection and changes due to antiviral treatments remain largely unknown. METHODS Liver biopsies and paired blood samples were obtained from HBeAg-positive patients before and after 48 weeks of entecavir treatment, and a probe-based capture strategy was applied for analyzing the HBV integrations in these samples. Serum HBV markers, including viral DNA, pgRNA, and HBsAg, were longitudinally assessed. RESULTS Entecavir treatment successfully reduced the levels of ALT, AST, and HBV serological markers (HBeAg, HBV pgRNA, and HBV DNA) in all patients (<40 years old). As expected, HBV integrations contributed to HBsAg production, with the total number of integrations positively correlated with serum HBsAg level (r = 0.47, P = 0.04). Along with repressed HBV replication, the number of viral integrations in liver biopsies decreased by about 1.94-fold after ETV treatment, with viral breakpoints significantly enriched within nt 1600-1900 of the HBV genome. No recurrent events were observed both at baseline and after treatment for the same individual, and only one same integration was found in two patients. Unlike in tumors, integrations in CHB biopsies seemed to have no chromosomal preference. Moreover, CHB integrations demonstrated lower enrichment scores for open active states than tumors, such as DNase, TssA, and ZNF/Rpts, and the scores reduced after ETV treatment. The antiviral therapy led to the disappearance of the enrichment tendency of integrations in both open chromatin and heterochromatin regions. CONCLUSION Reduced HBV replications by the nucleoside analogue may lead to decreased viral integrations in the liver, and those contributing to the HBsAg production may consistently occur. The pattern of HBV integration after ETV treatment is more random and irregular, which may contribute to a reduced risk of liver cancer due to antiviral treatment.
Collapse
|
30
|
Deymier S, Louvat C, Fiorini F, Cimarelli A. ISG20: an enigmatic antiviral RNase targeting multiple viruses. FEBS Open Bio 2022; 12:1096-1111. [PMID: 35174977 PMCID: PMC9157404 DOI: 10.1002/2211-5463.13382] [Citation(s) in RCA: 19] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2021] [Revised: 01/31/2022] [Accepted: 02/15/2022] [Indexed: 11/25/2022] Open
Abstract
Interferon-stimulated gene 20 kDa protein (ISG20) is a relatively understudied antiviral protein capable of inhibiting a broad spectrum of viruses. ISG20 exhibits strong RNase properties, and it belongs to the large family of DEDD exonucleases, present in both prokaryotes and eukaryotes. ISG20 was initially characterized as having strong RNase activity in vitro, suggesting that its inhibitory effects are mediated via direct degradation of viral RNAs. This mechanism of action has since been further elucidated and additional antiviral activities of ISG20 highlighted, including direct degradation of deaminated viral DNA and translational inhibition of viral RNA and nonself RNAs. This review focuses on the current understanding of the main molecular mechanisms of viral inhibition by ISG20 and discusses the latest developments on the features that govern specificity or resistance to its action.
Collapse
Affiliation(s)
- Séverine Deymier
- Centre International de Recherche en Infectiologie (CIRI)Université de LyonInsermU1111Université Claude Bernard Lyon 1CNRSUMR5308École Nationale Supérieur de LyonFrance
| | | | | | - Andrea Cimarelli
- Centre International de Recherche en Infectiologie (CIRI)Université de LyonInsermU1111Université Claude Bernard Lyon 1CNRSUMR5308École Nationale Supérieur de LyonFrance
| |
Collapse
|
31
|
Patel N, Abulwerdi F, Fatehi F, Manfield IW, Le Grice S, Schneekloth JS, Twarock R, Stockley PG. Dysregulation of Hepatitis B Virus Nucleocapsid Assembly in vitro by RNA-binding Small Ligands. J Mol Biol 2022; 434:167557. [PMID: 35341740 PMCID: PMC7612645 DOI: 10.1016/j.jmb.2022.167557] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2021] [Revised: 03/17/2022] [Accepted: 03/19/2022] [Indexed: 12/12/2022]
Abstract
RNA sequences/motifs dispersed across the genome of Hepatitis B Virus regulate formation of nucleocapsid-like particles (NCPs) by core protein (Cp) in vitro, in an epsilon/polymerase-independent fashion. These multiple RNA Packaging Signals (PSs) can each form stem-loops encompassing a Cp-recognition motif, -RGAG-, in their loops. Drug-like molecules that bind the most important of these PS sites for NCP assembly regulation with nanomolar affinities, were identified by screening an immobilized ligand library with a fluorescently-labelled, RNA oligonucleotide encompassing this sequence. Sixty-six of these "hits", with affinities ranging from low nanomolar to high micromolar, were purchased as non-immobilized versions. Their affinities for PSs and effects on NCP assembly were determined in vitro by Surface Plasmon Resonance. High-affinity ligand binding is dependent on the presence of an -RGAG- motif within the loop of the PS, consistent with ligand cross-binding between PS sites. Simple structure-activity relationships show that it is also dependent on the presence of specific functional groups in these ligands. Some compounds are potent inhibitors of in vitro NCP assembly at nanomolar concentrations. Despite appropriate logP values, these ligands do not inhibit HBV replication in cell culture. However, modelling confirms the potential of using PS-binding ligands to target NCP assembly as a novel anti-viral strategy. This also allows for computational exploration of potential synergic effects between anti-viral ligands directed at distinct molecular targets in vivo. HBV PS-regulated assembly can be dysregulated by novel small molecule RNA-binding ligands opening a novel target for developing directly-acting anti-virals against this major pathogen.
Collapse
Affiliation(s)
- Nikesh Patel
- Astbury Centre for Structural Molecular Biology, University of Leeds, Leeds LS2 9JT, UK. https://twitter.com/FBSResearch
| | - Fardokht Abulwerdi
- Center for Cancer Research, National Cancer Institute, Frederick, MD 21702-1201, United States
| | - Farzad Fatehi
- Department of Mathematics, University of York, York, YO10 5DD, UK; York Cross-disciplinary Centre for Systems Analysis, University of York, York, YO10 5GE, UK
| | - Iain W Manfield
- Astbury Centre for Structural Molecular Biology, University of Leeds, Leeds LS2 9JT, UK
| | - Stuart Le Grice
- Center for Cancer Research, National Cancer Institute, Frederick, MD 21702-1201, United States
| | - John S Schneekloth
- Center for Cancer Research, National Cancer Institute, Frederick, MD 21702-1201, United States
| | - Reidun Twarock
- Department of Mathematics, University of York, York, YO10 5DD, UK; York Cross-disciplinary Centre for Systems Analysis, University of York, York, YO10 5GE, UK; Department of Biology, University of York, York, YO10 5DD, UK
| | - Peter G Stockley
- Astbury Centre for Structural Molecular Biology, University of Leeds, Leeds LS2 9JT, UK. https://twitter.com/AstburyCentre
| |
Collapse
|
32
|
Tréguier Y, Bull-Maurer A, Roingeard P. Apolipoprotein E, a Crucial Cellular Protein in the Lifecycle of Hepatitis Viruses. Int J Mol Sci 2022; 23:ijms23073676. [PMID: 35409035 PMCID: PMC8998859 DOI: 10.3390/ijms23073676] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2022] [Revised: 03/19/2022] [Accepted: 03/25/2022] [Indexed: 02/01/2023] Open
Abstract
Apolipoprotein E (ApoE) is a multifunctional protein expressed in several tissues, including those of the liver. This lipoprotein component is responsible for maintaining lipid content homeostasis at the plasma and tissue levels by transporting lipids between the liver and peripheral tissues. The ability of ApoE to interact with host-cell surface receptors and its involvement in several cellular pathways raised questions about the hijacking of ApoE by hepatotropic viruses. Hepatitis C virus (HCV) was the first hepatitis virus reported to be dependent on ApoE for the completion of its lifecycle, with ApoE being part of the viral particle, mediating its entry into host cells and contributing to viral morphogenesis. Recent studies of the hepatitis B virus (HBV) lifecycle have revealed that this virus and its subviral envelope particles also incorporate ApoE. ApoE favors HBV entry and is crucial for the morphogenesis of infectious particles, through its interaction with HBV envelope glycoproteins. This review summarizes the data highlighting the crucial role of ApoE in the lifecycles of HBV and HCV and discusses its potential role in the lifecycle of other hepatotropic viruses.
Collapse
Affiliation(s)
- Yannick Tréguier
- INSERM U1259 MAVIVH, Université de Tours et CHU de Tours, 37032 Tours, France; (Y.T.); (A.B.-M.)
| | - Anne Bull-Maurer
- INSERM U1259 MAVIVH, Université de Tours et CHU de Tours, 37032 Tours, France; (Y.T.); (A.B.-M.)
| | - Philippe Roingeard
- INSERM U1259 MAVIVH, Université de Tours et CHU de Tours, 37032 Tours, France; (Y.T.); (A.B.-M.)
- Plateforme IBiSA des Microscopies, Université de Tours et CHU de Tours, 37032 Tours, France
- Correspondence: ; Tel.: +33-0247-366-232
| |
Collapse
|
33
|
Dörnbrack K, Beck J, Nassal M. Relaxing the restricted structural dynamics in the human hepatitis B virus RNA encapsidation signal enables replication initiation in vitro. PLoS Pathog 2022; 18:e1010362. [PMID: 35259189 PMCID: PMC8903280 DOI: 10.1371/journal.ppat.1010362] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2021] [Accepted: 02/10/2022] [Indexed: 11/18/2022] Open
Abstract
Hepadnaviruses, including hepatitis B virus (HBV) as a major human pathogen, replicate their tiny 3 kb DNA genomes by capsid-internal protein-primed reverse transcription of a pregenomic (pg) RNA. Initiation requires productive binding of the viral polymerase, P protein, to a 5´ proximal bipartite stem-loop, the RNA encapsidation signal ε. Then a residue in the central ε bulge directs the covalent linkage of a complementary dNMP to a Tyr sidechain in P protein´s Terminal Protein (TP) domain. After elongation by two or three nucleotides (nt) the TP-linked DNA oligo is transferred to a 3´ proximal acceptor, enabling full-length minus-strand DNA synthesis. No direct structural data are available on hepadnaviral initiation complexes but their cell-free reconstitution with P protein and ε RNA (Dε) from duck HBV (DHBV) provided crucial mechanistic insights, including on a major conformational rearrangement in the apical Dε part. Analogous cell-free systems for human HBV led at most to P—ε binding but no detectable priming. Here we demonstrate that local relaxation of the highly basepaired ε upper stem, by mutation or via synthetic split RNAs, enables ε-dependent in vitro priming with full-length P protein from eukaryotic translation extract yet also, and without additional macromolecules, with truncated HBV miniP proteins expressed in bacteria. Using selective 2-hydroxyl acylation analyzed by primer extension (SHAPE) we confirm that upper stem destabilization correlates with in vitro priming competence and show that the supposed bulge-closing basepairs are largely unpaired even in wild-type ε. We define the two 3´ proximal nt of this extended bulge as main initiation sites and provide evidence for a Dε-like opening of the apical ε part upon P protein binding. Beyond new HBV-specific basic aspects our novel in vitro priming systems should facilitate the development of high-throughput screens for priming inhibitors targeting this highly virus-specific process. Chronic hepatitis B virus (HBV) infection puts >250 million people at an increased risk for severe liver disease. Current treatments can control but rarely cure infection. HBV features a 3,200 bp DNA genome, generated by reverse transcription of a pregenomic (pg) RNA. To initiate DNA synthesis the viral polymerase, P protein, employs a stem-loop on pgRNA, ε, to covalently link a defined first nucleotide to its Terminal Protein (TP) domain. This protein-priming is highly virus-specific yet poorly understood. More is known for duck HBV (DHBV) where, different from HBV, protein-priming was successfully reconstituted in vitro years ago. One insight was that gaining priming-competence involves opening of the apical stem in DHBV ε RNA (Dε); in HBV ε the more extensive basepairing might restrict such dynamics. Here we relaxed these constraints by identifying functional but less stably folded, including split, HBV ε variants. Several such variants supported in vitro priming, including in a simple two-component-system employing a shortened recombinant P protein. Amongst other data the new cell-free systems yielded a first view on a major conformational change in HBV ε RNA bound to P protein, highlighting the importance of RNA dynamics for the human virus. Beyond furthering basic understanding our data should facilitate screening for protein-priming inhibitors as new anti-HBV agents.
Collapse
Affiliation(s)
- Katharina Dörnbrack
- Department of Internal Medicine II/Molecular Biology, University Hospital Freiburg, Freiburg, Germany
| | - Jürgen Beck
- Department of Internal Medicine II/Molecular Biology, University Hospital Freiburg, Freiburg, Germany
- * E-mail: (JB); , (MN)
| | - Michael Nassal
- Department of Internal Medicine II/Molecular Biology, University Hospital Freiburg, Freiburg, Germany
- * E-mail: (JB); , (MN)
| |
Collapse
|
34
|
Ghosh U, Sayef Ahammed K, Mishra S, Bhaumik A. The Emerging Roles of Silver Nanoparticles to Target Viral Life Cycle and Detect Viral Pathogens. Chem Asian J 2022; 17:e202101149. [PMID: 35020270 PMCID: PMC9011828 DOI: 10.1002/asia.202101149] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2021] [Revised: 01/05/2022] [Indexed: 11/26/2022]
Abstract
Along the line of recent vaccine advancements, new antiviral therapeutics are compelling to combat viral infection-related public health crises. Several properties of silver nanoparticles (AgNPs) such as low level of cytotoxicity, ease of tunability of the AgNPs in the ultra-small nanoscale size and shape through different convenient bottom-up chemistry approaches, high penetration of the composite with drug formulations into host cells has made AgNPs, a promising candidate for developing antivirals. In this review, we have highlighted the recent advancements in the AgNPs based nano-formulations to target cellular mechanisms of viral propagation, immune modulation of the host, and the ability to synergistically enhance the activity of existing antiviral drugs. On the other hand, we have discussed the recent advancements on AgNPs based detection of viral pathogens from clinical samples using inherent physicochemical properties. This article will provide an overview of our current knowledge on AgNPs based formulations that has promising potential for developing a counteractive strategy against emerging and existing viruses.
Collapse
Affiliation(s)
- Ujjyani Ghosh
- Cancer & Inflammatory Disorder DivisionCSIR-Indian Institute of Chemical BiologyJadavpur, Kolkata700032India
- Present address: The University of UtahSalt Lake CityUT84112USA
| | - Khondakar Sayef Ahammed
- Cancer & Inflammatory Disorder DivisionCSIR-Indian Institute of Chemical BiologyJadavpur, Kolkata700032India
- Present address: The University of Texas MD Anderson Cancer Center UTHealth Graduate School of Biomedical SciencesHoustonTX77030USA
| | - Snehasis Mishra
- Cancer & Inflammatory Disorder DivisionCSIR-Indian Institute of Chemical BiologyJadavpur, Kolkata700032India
| | - Asim Bhaumik
- School of Materials SciencesIndian Association for the Cultivation of ScienceJadavpur, Kolkata700 032India
| |
Collapse
|
35
|
Taverniti V, Ligat G, Debing Y, Kum DB, Baumert TF, Verrier ER. Capsid Assembly Modulators as Antiviral Agents against HBV: Molecular Mechanisms and Clinical Perspectives. J Clin Med 2022; 11:1349. [PMID: 35268440 PMCID: PMC8911156 DOI: 10.3390/jcm11051349] [Citation(s) in RCA: 24] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2022] [Revised: 02/25/2022] [Accepted: 02/25/2022] [Indexed: 02/07/2023] Open
Abstract
Despite a preventive vaccine being available, more than 250 million people suffer from chronic hepatitis B virus (HBV) infection, a major cause of liver disease and HCC. HBV infects human hepatocytes where it establishes its genome, the cccDNA with chromosomal features. Therapies controlling HBV replication exist; however, they are not sufficient to eradicate HBV cccDNA, the main cause for HBV persistence in patients. Core protein is the building block of HBV nucleocapsid. This viral protein modulates almost every step of the HBV life cycle; hence, it represents an attractive target for the development of new antiviral therapies. Capsid assembly modulators (CAM) bind to core dimers and perturb the proper nucleocapsid assembly. The potent antiviral activity of CAM has been demonstrated in cell-based and in vivo models. Moreover, several CAMs have entered clinical development. The aim of this review is to summarize the mechanism of action (MoA) and the advancements in the clinical development of CAMs and in the characterization of their mod of action.
Collapse
Affiliation(s)
- Valerio Taverniti
- Université de Strasbourg, Inserm, Institut de Recherche sur les Maladies Virales et Hépatiques UMR_S1110, 67000 Strasbourg, France; (V.T.); (G.L.); (T.F.B.)
| | - Gaëtan Ligat
- Université de Strasbourg, Inserm, Institut de Recherche sur les Maladies Virales et Hépatiques UMR_S1110, 67000 Strasbourg, France; (V.T.); (G.L.); (T.F.B.)
| | - Yannick Debing
- Aligos Belgium BV, 3001 Leuven, Belgium; (Y.D.); (D.B.K.)
| | | | - Thomas F. Baumert
- Université de Strasbourg, Inserm, Institut de Recherche sur les Maladies Virales et Hépatiques UMR_S1110, 67000 Strasbourg, France; (V.T.); (G.L.); (T.F.B.)
- Institut Hospitalo-Universitaire, Pôle Hépato-Digestif, Nouvel Hôpital Civil, 67000 Strasbourg, France
| | - Eloi R. Verrier
- Université de Strasbourg, Inserm, Institut de Recherche sur les Maladies Virales et Hépatiques UMR_S1110, 67000 Strasbourg, France; (V.T.); (G.L.); (T.F.B.)
| |
Collapse
|
36
|
Multiomics Analysis of Endocytosis upon HBV Infection and Identification of SCAMP1 as a Novel Host Restriction Factor against HBV Replication. Int J Mol Sci 2022; 23:ijms23042211. [PMID: 35216324 PMCID: PMC8874515 DOI: 10.3390/ijms23042211] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2021] [Revised: 02/08/2022] [Accepted: 02/11/2022] [Indexed: 02/04/2023] Open
Abstract
Hepatitis B virus (HBV) infection remains a major global health problem and the primary cause of cirrhosis and hepatocellular carcinoma (HCC). HBV intrusion into host cells is prompted by virus–receptor interactions in clathrin-mediated endocytosis. Here, we report a comprehensive view of the cellular endocytosis-associated transcriptome, proteome and ubiquitylome upon HBV infection. In this study, we quantified 273 genes in the transcriptome and 190 endocytosis-associated proteins in the proteome by performing multi-omics analysis. We further identified 221 Lys sites in 77 endocytosis-associated ubiquitinated proteins. A weak negative correlation was observed among endocytosis-associated transcriptome, proteome and ubiquitylome. We found 33 common differentially expressed genes (DEGs), differentially expressed proteins (DEPs), and Kub-sites. Notably, we reported the HBV-induced ubiquitination change of secretory carrier membrane protein (SCAMP1) for the first time, differentially expressed across all three omics data sets. Overexpression of SCAMP1 efficiently inhibited HBV RNAs/pgRNA and secreted viral proteins, whereas knockdown of SCAMP1 significantly increased viral production. Mechanistically, the EnhI/XP, SP1, and SP2 promoters were inhibited by SCAMP1, which accounts for HBV X and S mRNA inhibition. Overall, our study unveils the previously unknown role of SCAMP1 in viral replication and HBV pathogenesis and provides cumulative and novel information for a better understanding of endocytosis in response to HBV infection.
Collapse
|
37
|
N6-methyladenosine modification of the 5' epsilon structure of the HBV pregenome RNA regulates its encapsidation by the viral core protein. Proc Natl Acad Sci U S A 2022; 119:2120485119. [PMID: 35135882 PMCID: PMC8851549 DOI: 10.1073/pnas.2120485119] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/17/2022] [Indexed: 12/19/2022] Open
Abstract
HBV infections are the leading cause of chronic hepatitis and carry the risk of liver cirrhosis and cancer. The HBV life cycle is perpetuated by an RNA intermediate termed pregenomic RNA (pgRNA), which is encapsidated by the viral core protein. The pgRNA packaging process is an essential step in viral replication. Here, we investigated the role of N6-methyladenosine (m6A) modification in the recognition of pgRNA by the core protein during encapsidation. m6A modification of 5′ epsilon structural motifs serves as the recognition signal for the core protein interaction, as evidenced by the failure of 5′ epsilon m6A mutant to encapsidate pgRNA. This study identifies the structural role of m6A modification in pgRNA encapsidation and provides an avenue in RNA–protein complex interactions. Hepatitis B virus (HBV) contains a partially double-stranded DNA genome. During infection, its replication is mediated by reverse transcription (RT) of an RNA intermediate termed pregenomic RNA (pgRNA) within core particles in the cytoplasm. An epsilon structural element located in the 5′ end of the pgRNA primes the RT activity. We have previously identified the N6-methyladenosine (m6A)–modified DRACH motif at 1905 to 1909 nucleotides in the epsilon structure that affects myriad functions of the viral life cycle. In this study, we investigated the functional role of m6A modification of the 5′ ε (epsilon) structural element of the HBV pgRNA in the nucleocapsid assembly. Using the m6A site mutant in the HBV 5′ epsilon, we present evidence that m6A methylation of 5′ epsilon is necessary for its encapsidation. The m6A modification of 5′ epsilon increased the efficiency of viral RNA packaging, whereas the m6A of 3′ epsilon is dispensable for encapsidation. Similarly, depletion of methyltransferases (METTL3/14) decreased pgRNA and viral DNA levels within the core particles. Furthermore, the m6A modification at 5′ epsilon of HBV pgRNA promoted the interaction with core proteins, whereas the 5′ epsilon m6A site–mutated pgRNA failed to interact. HBV polymerase interaction with 5′ epsilon was independent of m6A modification of 5′ epsilon. This study highlights yet another pivotal role of m6A modification in dictating the key events of the HBV life cycle and provides avenues for investigating RNA–protein interactions in various biological processes, including viral RNA genome encapsidation in the context of m6A modification.
Collapse
|
38
|
Miyakawa K, Nishi M, Ogawa M, Matsunaga S, Sugiyama M, Nishitsuji H, Kimura H, Ohnishi M, Watashi K, Shimotohno K, Wakita T, Ryo A. Galectin-9 restricts hepatitis B virus replication via p62/SQSTM1-mediated selective autophagy of viral core proteins. Nat Commun 2022; 13:531. [PMID: 35087074 PMCID: PMC8795376 DOI: 10.1038/s41467-022-28171-5] [Citation(s) in RCA: 27] [Impact Index Per Article: 13.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2020] [Accepted: 01/10/2022] [Indexed: 12/31/2022] Open
Abstract
Autophagy has been linked to a wide range of functions, including a degradative process that defends host cells against pathogens. Although the involvement of autophagy in HBV infection has become apparent, it remains unknown whether selective autophagy plays a critical role in HBV restriction. Here, we report that a member of the galectin family, GAL9, directs the autophagic degradation of HBV HBc. BRET screening revealed that GAL9 interacts with HBc in living cells. Ectopic expression of GAL9 induces the formation of HBc-containing cytoplasmic puncta through interaction with another antiviral factor viperin, which co-localized with the autophagosome marker LC3. Mechanistically, GAL9 associates with HBc via viperin at the cytoplasmic puncta and enhanced the auto-ubiquitination of RNF13, resulting in p62 recruitment to form LC3-positive autophagosomes. Notably, both GAL9 and viperin are type I IFN-stimulated genes that act synergistically for the IFN-dependent proteolysis of HBc in HBV-infected hepatocytes. Collectively, these results reveal a previously undescribed antiviral mechanism against HBV in infected cells and a form of crosstalk between the innate immune system and selective autophagy in viral infection. In human cells, invading pathogens trigger an innate immune response that helps prevent viral replication and spread. Here, the authors reveal a mechanism of innate immunity that selectively leads to the autophagic degradation of hepatitis B virus core protein.
Collapse
Affiliation(s)
- Kei Miyakawa
- Department of Microbiology, Yokohama City University School of Medicine, Kanagawa, 236-0004, Japan
| | - Mayuko Nishi
- Department of Microbiology, Yokohama City University School of Medicine, Kanagawa, 236-0004, Japan
| | - Michinaga Ogawa
- Department of Bacteriology I, National Institute of Infectious Diseases, Tokyo, 162-8640, Japan
| | - Satoko Matsunaga
- Department of Microbiology, Yokohama City University School of Medicine, Kanagawa, 236-0004, Japan
| | - Masaya Sugiyama
- Genome Medical Sciences Project, National Center for Global Health and Medicine, Chiba, 272-8516, Japan
| | - Hironori Nishitsuji
- Research Center for Hepatitis and Immunology, National Center for Global Health and Medicine, Chiba, 272-8516, Japan
| | - Hirokazu Kimura
- School of Medical Technology, Faculty of Health Sciences, Gunma Paz University, Gunma, 370-0006, Japan
| | - Makoto Ohnishi
- Department of Bacteriology I, National Institute of Infectious Diseases, Tokyo, 162-8640, Japan
| | - Koichi Watashi
- Department of Virology II, National Institute of Infectious Diseases, Tokyo, 162-8640, Japan.,Research Center for Drug and Vaccine Development, National Institute of Infectious Diseases, Tokyo, 162-8640, Japan
| | - Kunitada Shimotohno
- Research Center for Hepatitis and Immunology, National Center for Global Health and Medicine, Chiba, 272-8516, Japan
| | - Takaji Wakita
- Department of Virology II, National Institute of Infectious Diseases, Tokyo, 162-8640, Japan
| | - Akihide Ryo
- Department of Microbiology, Yokohama City University School of Medicine, Kanagawa, 236-0004, Japan.
| |
Collapse
|
39
|
Yao Y, Yang B, Chen Y, Huang D, Liu C, Sun H, Hu X, Zhou Y, Wang Y, Chen J, Pei R, Wen Z, Chen X. RNA-Binding motif protein 38 (RBM38) mediates HBV pgRNA packaging into the nucleocapsid. Antiviral Res 2022; 198:105249. [PMID: 35041910 DOI: 10.1016/j.antiviral.2022.105249] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2021] [Revised: 12/10/2021] [Accepted: 01/12/2022] [Indexed: 12/12/2022]
Abstract
The binding of HBV polymerase (Pol) and the epsilon stem loop (ε) on the 5' terminal region of pgRNA is required for pgRNA packaging and HBV replication. Previous research has demonstrated that RNA binding motif protein 24 (RBM24) is involved in pgRNA packaging by mediating the interaction between HBV polymerase (Pol) and the ε element. Here, we demonstrate that RBM38 interacts with ε, pol, RBM24 and HBV core which mediate pgRNA packaging. RBM38 directly binds to the lower bulge of ε via RNA recognition submotifs (RNPs) and interacts with HBV Pol in an RNA-independent manner. RBM38 interacts with RBM24 and forms heterogeneous oligomers, which mediate Pol-ε binding and the formation of the Pol-RBM38/RBM24-ε complex. More important, RBM38 also binds to the HBV core via the C-terminal region (ARD domain), which facilitates the combination of Pol-ε with the HBV core protein. In conclusion, RBM38 facilitates the Pol-ε interaction and mediates Pol-ε in combining with the HBV core, triggering pgRNA packaging for reverse transcription and DNA synthesis. This study provides new insights into pgRNA encapsidation.
Collapse
Affiliation(s)
- Yongxuan Yao
- Joint Center of Translational Precision Medicine, Guangzhou Institute of Pediatrics, Guangzhou Women and Children Medical Center, Guangzhou, 510623, China; State Key Laboratory of Virology, Wuhan Institute of Virology, Center for Biosafety Mega-Science, Chinese Academy of Sciences, Wuhan, 430071, China
| | - Bo Yang
- Joint Center of Translational Precision Medicine, Guangzhou Institute of Pediatrics, Guangzhou Women and Children Medical Center, Guangzhou, 510623, China; State Key Laboratory of Virology, Wuhan Institute of Virology, Center for Biosafety Mega-Science, Chinese Academy of Sciences, Wuhan, 430071, China
| | - Yingshan Chen
- State Key Laboratory of Virology, Wuhan Institute of Virology, Center for Biosafety Mega-Science, Chinese Academy of Sciences, Wuhan, 430071, China; University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Dan Huang
- State Key Laboratory of Virology, Wuhan Institute of Virology, Center for Biosafety Mega-Science, Chinese Academy of Sciences, Wuhan, 430071, China; University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Canyu Liu
- State Key Laboratory of Virology, Wuhan Institute of Virology, Center for Biosafety Mega-Science, Chinese Academy of Sciences, Wuhan, 430071, China; University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Hao Sun
- State Key Laboratory of Virology, Wuhan Institute of Virology, Center for Biosafety Mega-Science, Chinese Academy of Sciences, Wuhan, 430071, China; University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Xue Hu
- State Key Laboratory of Virology, Wuhan Institute of Virology, Center for Biosafety Mega-Science, Chinese Academy of Sciences, Wuhan, 430071, China
| | - Yuan Zhou
- State Key Laboratory of Virology, Wuhan Institute of Virology, Center for Biosafety Mega-Science, Chinese Academy of Sciences, Wuhan, 430071, China
| | - Yun Wang
- State Key Laboratory of Virology, Wuhan Institute of Virology, Center for Biosafety Mega-Science, Chinese Academy of Sciences, Wuhan, 430071, China
| | - Jizheng Chen
- State Key Laboratory of Virology, Wuhan Institute of Virology, Center for Biosafety Mega-Science, Chinese Academy of Sciences, Wuhan, 430071, China
| | - Rongjuan Pei
- State Key Laboratory of Virology, Wuhan Institute of Virology, Center for Biosafety Mega-Science, Chinese Academy of Sciences, Wuhan, 430071, China.
| | - Zhe Wen
- Joint Center of Translational Precision Medicine, Guangzhou Institute of Pediatrics, Guangzhou Women and Children Medical Center, Guangzhou, 510623, China.
| | - Xinwen Chen
- State Key Laboratory of Virology, Wuhan Institute of Virology, Center for Biosafety Mega-Science, Chinese Academy of Sciences, Wuhan, 430071, China; Guangzhou Institutes of Biomedicine and Health, Guangzhou, 510530, China.
| |
Collapse
|
40
|
Kim SW, Yoon JS, Lee M, Cho Y. Toward a complete cure for chronic hepatitis B: Novel therapeutic targets for hepatitis B virus. Clin Mol Hepatol 2022; 28:17-30. [PMID: 34281294 PMCID: PMC8755466 DOI: 10.3350/cmh.2021.0093] [Citation(s) in RCA: 22] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/26/2021] [Revised: 07/05/2021] [Accepted: 07/18/2021] [Indexed: 11/09/2022] Open
Abstract
Hepatitis B virus (HBV) affects approximately 250 million patients worldwide, resulting in the progression to cirrhosis and hepatocellular carcinoma, which are serious public health problems. Although universal vaccination programs exist, they are only prophylactic and not curative. In the HBV life cycle, HBV forms covalently closed circular DNA (cccDNA), which is the viral minichromosome, in the nuclei of human hepatocytes and makes it difficult to achieve a complete cure with the current nucleos(t)ide analogs and interferon therapies. Current antiviral therapies rarely eliminate cccDNA; therefore, lifelong antiviral treatment is necessary. Recent trials for antiviral treatment of chronic hepatitis B have been focused on establishing a functional cure, defined by either the loss of hepatitis B surface antigen, undetectable serum HBV DNA levels, and/or seroconversion to hepatitis B surface antibody. Novel therapeutic targets and molecules are in the pipeline for early clinical trials aiming to cure HBV infection. The ideal strategy for achieving a long-lasting functional or complete cure might be using combination therapies targeting different steps of the HBV life cycle and immunomodulators. This review summarizes the current knowledge about novel treatments and combination treatments for a complete HBV cure.
Collapse
Affiliation(s)
- Sun Woong Kim
- Department of Internal Medicine, CHA Gangnam Medical Center, CHA University School of Medicine, Seoul, Korea
| | - Jun Sik Yoon
- Department of Internal Medicine, Busan Paik Hospital, Inje University College of Medicine, Busan, Korea
| | - Minjong Lee
- Department of Internal Medicine, Ewha Womans University College of Medicine, Seoul, Korea
| | - Yuri Cho
- Center for Liver and Pancreatobiliary Cancer, National Cancer Center, Goyang, Korea
| |
Collapse
|
41
|
Salpini R, D’Anna S, Benedetti L, Piermatteo L, Gill U, Svicher V, Kennedy PTF. Hepatitis B virus DNA integration as a novel biomarker of hepatitis B virus-mediated pathogenetic properties and a barrier to the current strategies for hepatitis B virus cure. Front Microbiol 2022; 13:972687. [PMID: 36118192 PMCID: PMC9478028 DOI: 10.3389/fmicb.2022.972687] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2022] [Accepted: 08/15/2022] [Indexed: 11/13/2022] Open
Abstract
Chronic infection with Hepatitis B Virus (HBV) is a major cause of liver-related morbidity and mortality worldwide. HBV-DNA integration into the human genome is recognized as a frequent event occurring during the early phases of HBV infection and characterizing the entire course of HBV natural history. The development of refined molecular biology technologies sheds new light on the functional implications of HBV-DNA integration into the human genome, including its role in the progression of HBV-related pathogenesis and in triggering the establishment of pro-oncogenic mechanisms, promoting the development of hepatocellular carcinoma. The present review provides an updated and comprehensive overview of the current body of knowledge on HBV-DNA integration, focusing on the molecular mechanisms underlying HBV-DNA integration and its occurrence throughout the different phases characterizing the natural history of HBV infection. Furthermore, here we discuss the main clinical implications of HBV integration as a biomarker of HBV-related pathogenesis, particularly in reference to hepatocarcinogenesis, and how integration may act as a barrier to the achievement of HBV cure with current and novel antiviral therapies. Overall, a more refined insight into the mechanisms and functionality of HBV integration is paramount, since it can potentially inform the design of ad hoc diagnostic tools with the ability to reveal HBV integration events perturbating relevant intracellular pathways and for identifying novel therapeutic strategies targeting alterations directly related to HBV integration.
Collapse
Affiliation(s)
- Romina Salpini
- Department of Experimental Medicine, University of Rome Tor Vergata, Roma, Italy
| | - Stefano D’Anna
- Department of Experimental Medicine, University of Rome Tor Vergata, Roma, Italy
| | - Livia Benedetti
- Department of Experimental Medicine, University of Rome Tor Vergata, Roma, Italy
| | - Lorenzo Piermatteo
- Department of Experimental Medicine, University of Rome Tor Vergata, Roma, Italy
| | - Upkar Gill
- Barts Liver Centre, Barts and The London School of Medicine and Dentistry, Blizard Institute, Queen Mary University of London, London, United Kingdom
| | - Valentina Svicher
- Department of Biology, University of Rome Tor Vergata, Roma, Italy
- *Correspondence: Valentina Svicher,
| | - Patrick T. F. Kennedy
- Barts Liver Centre, Barts and The London School of Medicine and Dentistry, Blizard Institute, Queen Mary University of London, London, United Kingdom
- Patrick T. F. Kennedy,
| |
Collapse
|
42
|
Bender D, Glitscher M, Hildt E. [Viral hepatitis A to E: prevalence, pathogen characteristics, and pathogenesis]. Bundesgesundheitsblatt Gesundheitsforschung Gesundheitsschutz 2021; 65:139-148. [PMID: 34932130 PMCID: PMC8813840 DOI: 10.1007/s00103-021-03472-0] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2021] [Accepted: 12/01/2021] [Indexed: 01/05/2023]
Abstract
Bei der viralen Hepatitis handelt es sich um eine akute oder chronische Entzündung der Leber, die durch verschiedene Viren verursacht wird. Weltweit leiden derzeit ca. 325 Mio. Menschen an der chronischen Form. Jährlich versterben insgesamt ca. 1,6 Mio. an den Folgen einer viralen Hepatitis. Die Hepatitisviren werden in 5 Erregergruppen unterteilt, die mit den Buchstaben A bis E bezeichnet werden (HAV–HEV). Diese unterscheiden sich in Phylogenie, Übertragung, Epidemiologie, Wirtsspezifität, Lebenszyklus, Struktur und in speziellen Aspekten der Pathogenese. Das strikt humanpathogene HAV, Teil der Familie Picornaviridae, induziert meist nur akute Hepatitiden und ist primär in Entwicklungsländern verbreitet. Das den Hepeviridae zugeordnete HEV beschreibt eine ähnliche Epidemiologie, ist jedoch durch sein zoonotisches Potenzial auch in Industrienationen weitverbreitet und kann zusätzlich eine chronische Erkrankung induzieren. Eine Chronifizierung tritt ebenso bei dem weltweit verbreiteten HBV (Hepadnaviridae) auf, dessen Satellitenvirus HDV (Kolmioviridae) das vorhandene kanzerogene Potenzial noch einmal erhöht. Das ebenfalls weltweit verbreitete HCV (Flaviviridae) birgt ein äußerst hohes Risiko der Chronifizierung und somit ebenfalls ein stark erhöhtes, kanzerogenes Potenzial. Die Erreger der viralen Hepatitis unterscheiden sich in ihren Eigenschaften und Lebenszyklen. Eine differenzierte Betrachtung im Hinblick auf Epidemiologie, Nachweismethoden und Prävention ist daher angezeigt. Obwohl robuste Therapien, und im Falle einzelner Erreger auch Vakzine, vorhanden sind, muss die Forschung insbesondere in Hinblick auf die armutsassoziierten Erreger erheblich vorangetrieben werden.
Collapse
Affiliation(s)
- Daniela Bender
- Abteilung Virologie, Paul-Ehrlich-Institut - Bundesinstitut für Impfstoffe und biomedizinische Arzneimittel, Paul-Ehrlich-Straße 51-59, 63225, Langen, Deutschland
| | - Mirco Glitscher
- Abteilung Virologie, Paul-Ehrlich-Institut - Bundesinstitut für Impfstoffe und biomedizinische Arzneimittel, Paul-Ehrlich-Straße 51-59, 63225, Langen, Deutschland
| | - Eberhard Hildt
- Abteilung Virologie, Paul-Ehrlich-Institut - Bundesinstitut für Impfstoffe und biomedizinische Arzneimittel, Paul-Ehrlich-Straße 51-59, 63225, Langen, Deutschland.
| |
Collapse
|
43
|
Abstract
Hepatitis B virus (HBV) is a hepatotropic, partially double-stranded DNA virus that replicates by reverse transcription and is a major cause of chronic liver disease and hepatocellular carcinoma. Reverse transcription is catalyzed by the four-domain multifunctional HBV polymerase (P) protein that has protein-priming, RNA- and DNA-dependent DNA synthesis (i.e., reverse transcriptase), and ribonuclease H activities. P also likely promotes the three strand transfers that occur during reverse transcription, and it may participate in immune evasion by HBV. Reverse transcription is primed by a tyrosine residue in the amino-terminal domain of P, and P remains covalently attached to the product DNA throughout reverse transcription. The reverse transcriptase activity of P is the target for the nucleos(t)ide analog drugs that dominate HBV treatment, and P is the target of ongoing efforts to develop new drugs against both the reverse transcriptase and ribonuclease H activities. Despite the unusual reverse transcription pathway catalyzed by P and the importance of P to HBV therapy, understanding the enzymology and structure of HBV P severely lags that of the retroviral reverse transcriptases due to substantial technical challenges to studying the enzyme. Obtaining a better understanding of P will broaden our appreciation of the diversity among reverse transcribing elements in nature, and will help improve treatment for people chronically infected with HBV.
Collapse
Affiliation(s)
- Daniel N Clark
- Department of Microbiology, Weber State University, Ogden, UT, United States
| | - Razia Tajwar
- Department of Molecular Microbiology and Immunology, Saint Louis University School of Medicine, Saint Louis, MO, United States
| | - Jianming Hu
- Department of Microbiology and Immunology, The Pennsylvania State University College of Medicine, Hershey, PA, United States
| | - John E Tavis
- Department of Molecular Microbiology and Immunology, Saint Louis University School of Medicine, Saint Louis, MO, United States.
| |
Collapse
|
44
|
Broennimann K, Ricardo-Lax I, Adler J, Michailidis E, de Jong YP, Reuven N, Shaul Y. RNR-R2 Upregulation by a Short Non-Coding Viral Transcript. Biomolecules 2021; 11:biom11121822. [PMID: 34944466 PMCID: PMC8698843 DOI: 10.3390/biom11121822] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2021] [Revised: 11/29/2021] [Accepted: 12/01/2021] [Indexed: 01/12/2023] Open
Abstract
DNA viruses require dNTPs for replication and have developed different strategies to increase intracellular dNTP pools. Hepatitis B virus (HBV) infects non-dividing cells in which dNTPs are scarce and the question is how viral replication takes place. Previously we reported that the virus induces the DNA damage response (DDR) pathway culminating in RNR-R2 expression and the generation of an active RNR holoenzyme, the key regulator of dNTP levels, leading to an increase in dNTPs. How the virus induces DDR and RNR-R2 upregulation is not completely known. The viral HBx open reading frame (ORF) was believed to trigger this pathway. Unexpectedly, however, we report here that the production of HBx protein is dispensable. We found that a small conserved region of 125 bases within the HBx ORF is sufficient to upregulate RNR-R2 expression in growth-arrested HepG2 cells and primary human hepatocytes. The observed HBV mRNA embedded regulatory element is named ERE. ERE in isolation is sufficient to activate the ATR-Chk1-E2F1-RNR-R2 DDR pathway. These findings demonstrate a non-coding function of HBV transcripts to support its propagation in non-cycling cells.
Collapse
Affiliation(s)
- Karin Broennimann
- Department of Molecular Genetics, Weizmann Institute of Science, Rehovot 76100, Israel; (K.B.); (I.R.-L.); (J.A.); (N.R.)
| | - Inna Ricardo-Lax
- Department of Molecular Genetics, Weizmann Institute of Science, Rehovot 76100, Israel; (K.B.); (I.R.-L.); (J.A.); (N.R.)
- Laboratory of Virology and Infectious Disease, Rockefeller University, New York, NY 10065, USA; (E.M.); (Y.P.d.J.)
| | - Julia Adler
- Department of Molecular Genetics, Weizmann Institute of Science, Rehovot 76100, Israel; (K.B.); (I.R.-L.); (J.A.); (N.R.)
| | - Eleftherios Michailidis
- Laboratory of Virology and Infectious Disease, Rockefeller University, New York, NY 10065, USA; (E.M.); (Y.P.d.J.)
| | - Ype P. de Jong
- Laboratory of Virology and Infectious Disease, Rockefeller University, New York, NY 10065, USA; (E.M.); (Y.P.d.J.)
- Division of Gastroenterology and Hepatology, Weill Cornell Medicine, New York, NY 10065, USA
| | - Nina Reuven
- Department of Molecular Genetics, Weizmann Institute of Science, Rehovot 76100, Israel; (K.B.); (I.R.-L.); (J.A.); (N.R.)
| | - Yosef Shaul
- Department of Molecular Genetics, Weizmann Institute of Science, Rehovot 76100, Israel; (K.B.); (I.R.-L.); (J.A.); (N.R.)
- Correspondence: ; Tel.: +972-8-934-2320
| |
Collapse
|
45
|
Analysis of the Physicochemical Properties, Replication and Pathophysiology of a Massively Glycosylated Hepatitis B Virus HBsAg Escape Mutant. Viruses 2021; 13:v13112328. [PMID: 34835134 PMCID: PMC8622389 DOI: 10.3390/v13112328] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2021] [Revised: 11/17/2021] [Accepted: 11/21/2021] [Indexed: 02/07/2023] Open
Abstract
Mutations in HBsAg, the surface antigen of the hepatitis B virus (HBV), might affect the serum HBV DNA level of HBV-infected patients, since the reverse transcriptase (RT) domain of HBV polymerase overlaps with the HBsAg-coding region. We previously identified a diagnostic escape mutant (W3S) HBV that produces massively glycosylated HBsAg. In this study, we constructed an HBV-producing vector that expresses W3S HBs (pHB-W3S) along with a wild-type HBV-producing plasmid (pHB-WT) in order to analyze the physicochemical properties, replication, and antiviral drug response of the mutant. Transfection of either pHB-WT or W3S into HepG2 cells yielded similar CsCl density profiles and eAg expression, as did transfection of a glycosylation defective mutant, pHB-W3S (N146G), in which a glycosylation site at the 146aa asparagine (N) site of HBs was mutated to glycine (G). Virion secretion, however, seemed to be severely impaired in cases of pHB-W3S and pHB-W3S (N146G), compared with pHB-WT, as determined by qPCR and Southern blot analysis. Furthermore, inhibition of glycosylation using tunicamycinTM on wild-type HBV production also reduced the virion secretion. These results suggested that the HBV core and Dane particle could be formed either by massively glycosylated or glycosylation-defective HBsAg, but reduced and/or almost completely blocked the virion secretion efficiency, indicating that balanced glycosylation of HBsAg is required for efficient release of HBV, and mutations inducing an imbalanced glycosylation of HBs would cause the virion to become stuck in the cells, which might be associated with various pathogeneses due to HBV infection.
Collapse
|
46
|
Abstract
Janus protein tyrosine kinase (JAK) has the ability to activate signal transducer and activator of transcription (STAT). STAT3 is a valued member of the JAK/STAT signaling pathway. In recent years, several studies have documented that STAT3 is closely related to the occurrence and development of liver fibrosis caused by various factors. Activation of STAT3 can play anti- or pro-inflammatory roles in the pathogenesis of liver fibrosis. This article reviewed the recent studies on STAT3 in the development of various liver fibrosis to find a more effective method to relieve and cure liver diseases, such as hepatitis B virus (HBV), non-alcoholic fatty liver disease (NAFLD), schistosomiasis, and chemical liver injury.
Collapse
|
47
|
Efficient Inhibition of Hepatitis B Virus (HBV) Replication and cccDNA Formation by HBV Ribonuclease H Inhibitors during Infection. Antimicrob Agents Chemother 2021; 65:e0146021. [PMID: 34516242 DOI: 10.1128/aac.01460-21] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
The hepatitis B virus (HBV) ribonuclease H (RNase H) is an attractive but unexploited drug target. Here, we addressed three limitations to the current state of RNase H inhibitor development: (a) Efficacy has been assessed only in transfected cell lines. (b) Cytotoxicity data are from transformed cell lines rather than primary cells. (c) It is unknown how the compounds work against nucleos(t)ide analog resistant HBV strains. Three RNase H inhibitors from different chemotypes, 110 (α-hydroxytropolone), 1133 (N-hydroxypyridinedione), and 1073 (N-hydroxynapthyridinone), were tested in HBV-infected HepG2-NTCP cells for inhibition of cccDNA accumulation and HBV product formation. 50% effective concentrations (EC50s) were 0.049-0.078 μM in the infection studies compared to 0.29-1.6 μM in transfected cells. All compounds suppressed cccDNA formation by >98% at 5 μM when added shortly after infection. HBV RNA, intracellular and extracellular DNA, and HBsAg secretion were all robustly suppressed. The greater efficacy of the inhibitors when added shortly after infection is presumably due to blocking amplification of the HBV cccDNA, which suppresses events downstream of cccDNA formation. The compounds had 50% cytotoxic concentrations (CC50s) of 16-100 μM in HepG2-derived cell lines but were nontoxic in primary human hepatocytes, possibly due to the quiescent state of the hepatocytes. The compounds had similar EC50s against replication of wild-type, lamivudine-resistant, and adefovir/lamivudine-resistant HBV, as expected because the RNase H inhibitors do not target the viral reverse transcriptase active site. These studies expand confidence in inhibiting the HBV RNase H as a drug strategy and support inclusion of RNase H inhibitors in novel curative drug combinations for HBV.
Collapse
|
48
|
Lin J, Li J, Xie P, Han Y, Yu D, Chen J, Zhang X. Hepatitis B virus middle surface antigen loss promotes clinical variant persistence in mouse models. Virulence 2021; 12:2868-2882. [PMID: 34738866 PMCID: PMC8632123 DOI: 10.1080/21505594.2021.1999130] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
Abstract
Hepatitis B virus (HBV) middle surface antigen (MHBs) mutation or deletion occurs in patients with chronic HBV infection. However, the functional role of MHBs in HBV infection is still an enigma. Here, we reported that 7.33% (11/150) isolates of CHB patients had MHBs start codon mutations compared with 0.00% (0/146) in acute hepatitis B (AHB) patients. Interestingly, MHBs loss accounted for 11.88% (126/1061) isolates from NCBI GenBank, compared with 0.09% (1/1061) and 0.00% (0/1061) for HBV large surface antigen (LHBs) loss and HBV small surface antigen (SHBs) loss, respectively. One persistent HBV clone of genotype B (B56, MHBs loss) from a CHB patient was hydrodynamically injected into BALB/c mice. B56 persisted for >70 weeks in BALB/c mice, whereas B56 with restored MHBs (B56M+) was quickly cleared within 28 days. Serum cytokine assays demonstrated that CXCL1, CXCL2, IL-6 and IL-33 were significantly increased during rapid HBV clearance in B56M+ mice. Furthermore, the enhancers and promoters of B56 were proved to be required for B56 persistence in mice. Ablating MHBs expression improved the persistence of a new clone (HBV1.3, genotype B) which was recreated by using enhancers and promoters of B56. These data demonstrated that MHBs deletion can promote the persistence of specific HBV variants in a hydrodynamic mouse model. MHBs re-expression restored a rapid clearance of HBV, which was accompanied by cytokine responses including the elevation of CXCL1, CXCL2, IL-6 and IL-33.
Collapse
Affiliation(s)
- Junyu Lin
- Department of Infectious Diseases, Research Laboratory of Clinical Virology, National Research Center for Translational Medicine (Shanghai), Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Jing Li
- Department of Infectious Diseases, Research Laboratory of Clinical Virology, National Research Center for Translational Medicine (Shanghai), Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Peilin Xie
- Department of Infectious Diseases, Research Laboratory of Clinical Virology, National Research Center for Translational Medicine (Shanghai), Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Yue Han
- Department of Infectious Diseases, Research Laboratory of Clinical Virology, National Research Center for Translational Medicine (Shanghai), Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Demin Yu
- Department of Infectious Diseases, Research Laboratory of Clinical Virology, National Research Center for Translational Medicine (Shanghai), Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Jia Chen
- Department of Infectious Diseases, Research Laboratory of Clinical Virology, National Research Center for Translational Medicine (Shanghai), Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Xinxin Zhang
- Department of Infectious Diseases, Research Laboratory of Clinical Virology, National Research Center for Translational Medicine (Shanghai), Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| |
Collapse
|
49
|
Niklasch M, Zimmermann P, Nassal M. The Hepatitis B Virus Nucleocapsid-Dynamic Compartment for Infectious Virus Production and New Antiviral Target. Biomedicines 2021; 9:1577. [PMID: 34829806 PMCID: PMC8615760 DOI: 10.3390/biomedicines9111577] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2021] [Revised: 10/19/2021] [Accepted: 10/21/2021] [Indexed: 12/11/2022] Open
Abstract
Hepatitis B virus (HBV) is a small enveloped DNA virus which replicates its tiny 3.2 kb genome by reverse transcription inside an icosahedral nucleocapsid, formed by a single ~180 amino acid capsid, or core, protein (Cp). HBV causes chronic hepatitis B (CHB), a severe liver disease responsible for nearly a million deaths each year. Most of HBV's only seven primary gene products are multifunctional. Though less obvious than for the multi-domain polymerase, P protein, this is equally crucial for Cp with its multiple roles in the viral life-cycle. Cp provides a stable genome container during extracellular phases, allows for directed intracellular genome transport and timely release from the capsid, and subsequent assembly of new nucleocapsids around P protein and the pregenomic (pg) RNA, forming a distinct compartment for reverse transcription. These opposing features are enabled by dynamic post-transcriptional modifications of Cp which result in dynamic structural alterations. Their perturbation by capsid assembly modulators (CAMs) is a promising new antiviral concept. CAMs inappropriately accelerate assembly and/or distort the capsid shell. We summarize the functional, biochemical, and structural dynamics of Cp, and discuss the therapeutic potential of CAMs based on clinical data. Presently, CAMs appear as a valuable addition but not a substitute for existing therapies. However, as part of rational combination therapies CAMs may bring the ambitious goal of a cure for CHB closer to reality.
Collapse
Affiliation(s)
| | | | - Michael Nassal
- Internal Medicine II/Molecular Biology, University Hospital Freiburg, Hugstetter Str. 55, D-79106 Freiburg, Germany; (M.N.); (P.Z.)
| |
Collapse
|
50
|
Core Protein-Directed Antivirals and Importin β Can Synergistically Disrupt HBV Capsids. J Virol 2021; 96:e0139521. [PMID: 34705562 DOI: 10.1128/jvi.01395-21] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Viral structural proteins can have multiple activities. Antivirals that target structural proteins have potential to exhibit multiple antiviral mechanisms. Hepatitis B Virus (HBV) core protein (Cp) is involved in most stages of the viral lifecycle: it assembles into capsids, packages viral RNA, is a metabolic compartment for reverse transcription, interacts with nuclear trafficking machinery, and disassembles to release the viral genome into the nucleus. During nuclear localization, HBV capsids bind to host importins (e.g. Impβ) via Cp's C-terminal domain (CTD); the CTD is localized to the interior of the capsid and is transiently exposed on the exterior. We used HAP12 as a representative Cp Allosteric Modulators (CpAMs), a class of antivirals that inappropriately stimulates and misdirects HBV assembly and deforms capsids. CpAM impact on other aspects of the HBV lifecycle is poorly understood. We investigated how HAP12 influenced the interactions between empty or RNA-filled capsids with Impβ and trypsin in vitro. We showed that HAP12 can modulate CTD accessibility and capsid stability, depending on the saturation of HAP12-binding sites. We demonstrated that Impβ synergistically contributes to capsid disruption at high levels of HAP12 saturation, using electron microscopy to visualize disruption and rearrangement of Cp dimers into aberrant complexes. However, RNA-filled capsids resisted the destabilizing effects of HAP12 and Impβ. In summary, we show host protein-induced catalysis of capsid disruption, an unexpected additional mechanism of action for CpAMs. Potentially, untimely capsid disassembly can hamper the HBV lifecycle and also cause the virus to become vulnerable to host innate immune responses. IMPORTANCE The HBV core, an icosahedral complex of 120 copies of the homodimeric core (capsid) protein with or without packaged nucleic acid, is transported to the host nucleus by its interaction with host importin proteins. Importin-core interaction requires the core protein C-terminal domain, which is inside the capsid, to "flip" to the capsid exterior. Core-protein directed drugs that affect capsid assembly and stability have been developed recently. We show that these molecules can, synergistically with importins, disrupt capsids. This mechanism of action, synergism with host protein, has potential to disrupt the virus lifecycle and activate the innate immune system.
Collapse
|