|
1
|
Khan M, Irvin P, Park SB, Ivester HM, Ricardo-Lax I, Leek M, Grieshaber A, Jang ES, Coutermarsh-Ott S, Zhang Q, Maio N, Jiang JK, Li B, Huang W, Wang AQ, Xu X, Hu Z, Zheng W, Ye Y, Rouault T, Rice C, Allen IC, Liang TJ. Repurposing of lonafarnib as a treatment for SARS-CoV-2 infection. JCI Insight 2025; 10:e182704. [PMID: 39625789 PMCID: PMC11721293 DOI: 10.1172/jci.insight.182704] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2024] [Accepted: 11/19/2024] [Indexed: 01/30/2025] Open
Abstract
Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), which causes coronavirus disease 2019 (COVID-19), has emerged as a global pandemic pathogen with high mortality. While treatments have been developed to reduce morbidity and mortality of COVID-19, more antivirals with broad-spectrum activities are still needed. Here, we identified lonafarnib (LNF), a Food and Drug Administration-approved inhibitor of cellular farnesyltransferase (FTase), as an effective anti-SARS-CoV-2 agent. LNF inhibited SARS-CoV-2 infection and acted synergistically with known anti-SARS antivirals. LNF was equally active against diverse SARS-CoV-2 variants. Mechanistic studies suggested that LNF targeted multiple steps of the viral life cycle. Using other structurally diverse FTase inhibitors and a LNF-resistant FTase mutant, we demonstrated a key role of FTase in the SARS-CoV-2 life cycle. To demonstrate in vivo efficacy, we infected SARS-CoV-2-susceptible humanized mice expressing human angiotensin-converting enzyme 2 (ACE2) and treated them with LNF. LNF at a clinically relevant dose suppressed the viral titer in the respiratory tract and improved pulmonary pathology and clinical parameters. Our study demonstrated that LNF, an approved oral drug with excellent human safety data, is a promising antiviral against SARS-CoV-2 that warrants further clinical assessment for treatment of COVID-19 and potentially other viral infections.
Collapse
Affiliation(s)
- Mohsin Khan
- Liver Diseases Branch, National Institute of Diabetes and Digestive and Kidney Diseases, NIH, Bethesda, Maryland, USA
| | - Parker Irvin
- Liver Diseases Branch, National Institute of Diabetes and Digestive and Kidney Diseases, NIH, Bethesda, Maryland, USA
| | - Seung Bum Park
- Liver Diseases Branch, National Institute of Diabetes and Digestive and Kidney Diseases, NIH, Bethesda, Maryland, USA
| | - Hannah M. Ivester
- Department of Biomedical Sciences and Pathobiology, Virginia-Maryland College of Veterinary Medicine, Virginia Tech, Blacksburg, Virginia, USA
| | - Inna Ricardo-Lax
- Laboratory of Virology and Infectious Disease, The Rockefeller University, New York, New York, USA
| | - Madeleine Leek
- Liver Diseases Branch, National Institute of Diabetes and Digestive and Kidney Diseases, NIH, Bethesda, Maryland, USA
| | - Ailis Grieshaber
- Liver Diseases Branch, National Institute of Diabetes and Digestive and Kidney Diseases, NIH, Bethesda, Maryland, USA
| | - Eun Sun Jang
- Liver Diseases Branch, National Institute of Diabetes and Digestive and Kidney Diseases, NIH, Bethesda, Maryland, USA
| | - Sheryl Coutermarsh-Ott
- Department of Biomedical Sciences and Pathobiology, Virginia-Maryland College of Veterinary Medicine, Virginia Tech, Blacksburg, Virginia, USA
| | - Qi Zhang
- Division of Preclinical Innovation, National Center for Advancing Translational Sciences, NIH, Rockville, Maryland, USA
| | - Nunziata Maio
- Eunice Kennedy Shriver National Institute of Child Health and Human Development, NIH, Bethesda, Maryland, USA
| | - Jian-Kang Jiang
- Division of Preclinical Innovation, National Center for Advancing Translational Sciences, NIH, Rockville, Maryland, USA
| | - Bing Li
- Division of Preclinical Innovation, National Center for Advancing Translational Sciences, NIH, Rockville, Maryland, USA
| | - Wenwei Huang
- Division of Preclinical Innovation, National Center for Advancing Translational Sciences, NIH, Rockville, Maryland, USA
| | - Amy Q. Wang
- Division of Preclinical Innovation, National Center for Advancing Translational Sciences, NIH, Rockville, Maryland, USA
| | - Xin Xu
- Division of Preclinical Innovation, National Center for Advancing Translational Sciences, NIH, Rockville, Maryland, USA
| | - Zongyi Hu
- Liver Diseases Branch, National Institute of Diabetes and Digestive and Kidney Diseases, NIH, Bethesda, Maryland, USA
| | - Wei Zheng
- Division of Preclinical Innovation, National Center for Advancing Translational Sciences, NIH, Rockville, Maryland, USA
| | - Yihong Ye
- Laboratory of Molecular Biology, National Institute of Diabetes and Digestive and Kidney Diseases, NIH, Bethesda, Maryland, USA
| | - Tracey Rouault
- Eunice Kennedy Shriver National Institute of Child Health and Human Development, NIH, Bethesda, Maryland, USA
| | - Charles Rice
- Laboratory of Virology and Infectious Disease, The Rockefeller University, New York, New York, USA
| | - Irving C. Allen
- Department of Biomedical Sciences and Pathobiology, Virginia-Maryland College of Veterinary Medicine, Virginia Tech, Blacksburg, Virginia, USA
| | - T. Jake Liang
- Liver Diseases Branch, National Institute of Diabetes and Digestive and Kidney Diseases, NIH, Bethesda, Maryland, USA
| |
Collapse
|
|
2
|
Quirino A, Marascio N, Branda F, Ciccozzi A, Romano C, Locci C, Azzena I, Pascale N, Pavia G, Matera G, Casu M, Sanna D, Giovanetti M, Ceccarelli G, Alaimo di Loro P, Ciccozzi M, Scarpa F, Maruotti A. Viral Hepatitis: Host Immune Interaction, Pathogenesis and New Therapeutic Strategies. Pathogens 2024; 13:766. [PMID: 39338957 PMCID: PMC11435051 DOI: 10.3390/pathogens13090766] [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: 08/04/2024] [Revised: 08/30/2024] [Accepted: 09/02/2024] [Indexed: 09/30/2024] Open
Abstract
Viral hepatitis is a major cause of liver illness worldwide. Despite advances in the understanding of these infections, the pathogenesis of hepatitis remains a complex process driven by intricate interactions between hepatitis viruses and host cells at the molecular level. This paper will examine in detail the dynamics of these host-pathogen interactions, highlighting the key mechanisms that regulate virus entry into the hepatocyte, their replication, evasion of immune responses, and induction of hepatocellular damage. The unique strategies employed by different hepatitis viruses, such as hepatitis B, C, D, and E viruses, to exploit metabolic and cell signaling pathways to their advantage will be discussed. At the same time, the innate and adaptive immune responses put in place by the host to counter viral infection will be analyzed. Special attention will be paid to genetic, epigenetic, and environmental factors that modulate individual susceptibility to different forms of viral hepatitis. In addition, this work will highlight the latest findings on the mechanisms of viral persistence leading to the chronic hepatitis state and the potential implications for the development of new therapeutic strategies. Fully understanding the complex host-pathogen interactions in viral hepatitis is crucial to identifying new therapeutic targets, developing more effective approaches for treatment, and shedding light on the mechanisms underlying progression to more advanced stages of liver damage.
Collapse
Affiliation(s)
- Angela Quirino
- Unit of Clinical Microbiology, Department of Health Sciences, “Magna Græcia” University of Catanzaro “Renato Dulbecco” Teaching Hospital, 88100 Catanzaro, Italy; (A.Q.); (N.M.); (G.P.); (G.M.)
| | - Nadia Marascio
- Unit of Clinical Microbiology, Department of Health Sciences, “Magna Græcia” University of Catanzaro “Renato Dulbecco” Teaching Hospital, 88100 Catanzaro, Italy; (A.Q.); (N.M.); (G.P.); (G.M.)
| | - Francesco Branda
- Unit of Medical Statistics and Molecular Epidemiology, Università Campus Bio-Medico di Roma, 00128 Rome, Italy; (C.R.); (M.C.)
| | - Alessandra Ciccozzi
- Department of Biomedical Sciences, University of Sassari, 07100 Sassari, Italy; (A.C.); (C.L.); (D.S.); (F.S.)
| | - Chiara Romano
- Unit of Medical Statistics and Molecular Epidemiology, Università Campus Bio-Medico di Roma, 00128 Rome, Italy; (C.R.); (M.C.)
| | - Chiara Locci
- Department of Biomedical Sciences, University of Sassari, 07100 Sassari, Italy; (A.C.); (C.L.); (D.S.); (F.S.)
- Department of Veterinary Medicine, University of Sassari, 07100 Sassari, Italy; (I.A.); (N.P.); (M.C.)
| | - Ilenia Azzena
- Department of Veterinary Medicine, University of Sassari, 07100 Sassari, Italy; (I.A.); (N.P.); (M.C.)
| | - Noemi Pascale
- Department of Veterinary Medicine, University of Sassari, 07100 Sassari, Italy; (I.A.); (N.P.); (M.C.)
- Department of Chemical Physical Mathematical and Natural Sciences, University of Sassari, 07100 Sassari, Italy
| | - Grazia Pavia
- Unit of Clinical Microbiology, Department of Health Sciences, “Magna Græcia” University of Catanzaro “Renato Dulbecco” Teaching Hospital, 88100 Catanzaro, Italy; (A.Q.); (N.M.); (G.P.); (G.M.)
| | - Giovanni Matera
- Unit of Clinical Microbiology, Department of Health Sciences, “Magna Græcia” University of Catanzaro “Renato Dulbecco” Teaching Hospital, 88100 Catanzaro, Italy; (A.Q.); (N.M.); (G.P.); (G.M.)
| | - Marco Casu
- Department of Veterinary Medicine, University of Sassari, 07100 Sassari, Italy; (I.A.); (N.P.); (M.C.)
| | - Daria Sanna
- Department of Biomedical Sciences, University of Sassari, 07100 Sassari, Italy; (A.C.); (C.L.); (D.S.); (F.S.)
| | - Marta Giovanetti
- Department of Sciences and Technologies for Sustainable Development and One Health, Università Campus Bio-Medico di Roma, 00128 Rome, Italy;
- Instituto René Rachou, Fundação Oswaldo Cruz, Belo Horizonte 30190-002, MG, Brazil
- Climate Amplified Diseases and Epidemics (CLIMADE), Brasilia 70070-130, GO, Brazil
| | - Giancarlo Ceccarelli
- Department of Public Health and Infectious Diseases, University Hospital Policlinico Umberto I, Sapienza University of Rome, 00161 Rome, Italy;
| | | | - Massimo Ciccozzi
- Unit of Medical Statistics and Molecular Epidemiology, Università Campus Bio-Medico di Roma, 00128 Rome, Italy; (C.R.); (M.C.)
| | - Fabio Scarpa
- Department of Biomedical Sciences, University of Sassari, 07100 Sassari, Italy; (A.C.); (C.L.); (D.S.); (F.S.)
| | - Antonello Maruotti
- Department GEPLI, Libera Università Maria Ss Assunta, 00193 Rome, Italy;
| |
Collapse
|
|
3
|
Abdul Majeed N, Zehnder B, Koh C, Heller T, Urban S. Hepatitis delta: Epidemiology to recent advances in therapeutic agents. Hepatology 2023; 78:1306-1321. [PMID: 36738087 DOI: 10.1097/hep.0000000000000331] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/02/2022] [Accepted: 12/19/2022] [Indexed: 02/05/2023]
Abstract
Hepatitis D virus (HDV) was first described in 1977 and is dependent on the presence of hepatitis B surface antigen (HBsAg) for its entry into cells and on the human host for replication. Due to the envelopment with the hepatitis B virus (HBV) envelope, early phases of HDV entry resemble HBV infection. Unlike HBV, HDV activates innate immune responses. The global prevalence of HDV is estimated to be about 5% of HBsAg positive individuals. However, recent studies have described a wide range of prevalence between 12 to 72 million individuals. Infection can occur as super-infection or co-infection. The diagnosis of active HDV infection involves screening with anti HDV antibodies followed by quantitative PCR testing for HDV RNA in those who are HBsAg positive. The diagnostic studies have evolved over the years improving the validity and reliability of the tests performed. HDV infection is considered the most severe form of viral hepatitis and the HDV genotype may influence the disease course. There are eight major HDV genotypes with prevalence varying by geographic region. HDV treatment has been challenging as HDV strongly depends on the host cell for replication and provides few, if any viral targets. Better understanding of HDV virology has led to the development of several therapeutic agents currently being studied in different phase II and III clinical trials. There is increasing promise of effective therapies that will ameliorate the course of this devastating disease.
Collapse
Affiliation(s)
- Nehna Abdul Majeed
- Liver Diseases Branch, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, Maryland, USA
| | - Benno Zehnder
- Department of Infectious Diseases, Molecular Virology, University Hospital Heidelberg, Heidelberg, Germany
| | - Christopher Koh
- Liver Diseases Branch, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, Maryland, USA
| | - Theo Heller
- Liver Diseases Branch, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, Maryland, USA
| | - Stephan Urban
- Department of Infectious Diseases, Molecular Virology, University Hospital Heidelberg, Heidelberg, Germany
- German Center for Infection Research (DZIF) - Heidelberg Partner Site, Heidelberg, Germany
| |
Collapse
|
|
4
|
Thiyagarajah K, Basic M, Hildt E. Cellular Factors Involved in the Hepatitis D Virus Life Cycle. Viruses 2023; 15:1687. [PMID: 37632029 PMCID: PMC10459925 DOI: 10.3390/v15081687] [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: 06/30/2023] [Revised: 07/30/2023] [Accepted: 08/01/2023] [Indexed: 08/27/2023] Open
Abstract
Hepatitis D virus (HDV) is a defective RNA virus with a negative-strand RNA genome encompassing less than 1700 nucleotides. The HDV genome encodes only for one protein, the hepatitis delta antigen (HDAg), which exists in two forms acting as nucleoproteins. HDV depends on the envelope proteins of the hepatitis B virus as a helper virus for packaging its ribonucleoprotein complex (RNP). HDV is considered the causative agent for the most severe form of viral hepatitis leading to liver fibrosis/cirrhosis and hepatocellular carcinoma. Many steps of the life cycle of HDV are still enigmatic. This review gives an overview of the complete life cycle of HDV and identifies gaps in knowledge. The focus is on the description of cellular factors being involved in the life cycle of HDV and the deregulation of cellular pathways by HDV with respect to their relevance for viral replication, morphogenesis and HDV-associated pathogenesis. Moreover, recent progress in antiviral strategies targeting cellular structures is summarized in this article.
Collapse
Affiliation(s)
| | | | - Eberhard Hildt
- Paul-Ehrlich-Institute, Department of Virology, D-63225 Langen, Germany; (K.T.); (M.B.)
| |
Collapse
|
|
5
|
Brunetto MR, Ricco G, Negro F, Wedemeyer H, Yurdaydin C, Asselah T, Papatheodoridis G, Gheorghe L, Agarwal K, Farci P, Buti M. EASL Clinical Practice Guidelines on hepatitis delta virus. J Hepatol 2023; 79:433-460. [PMID: 37364791 DOI: 10.1016/j.jhep.2023.05.001] [Citation(s) in RCA: 109] [Impact Index Per Article: 54.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/01/2023] [Accepted: 05/01/2023] [Indexed: 06/28/2023]
Abstract
Hepatitis D virus (HDV) is a defective virus that requires the hepatitis B virus to complete its life cycle and cause liver damage in humans. HDV is responsible for rare acute and chronic liver diseases and is considered the most aggressive hepatitis virus. Acute infection can cause acute liver failure, while persistent infection typically causes a severe form of chronic hepatitis which is associated with rapid and frequent progression to cirrhosis and its end-stage complications, hepatic decompensation and hepatocellular carcinoma. Major diagnostic and therapeutic innovations prompted the EASL Governing Board to commission specific Clinical Practice Guidelines on the identification, virologic and clinical characterisation, prognostic assessment, and appropriate clinical and therapeutic management of HDV-infected individuals.
Collapse
|
|
6
|
Khalfi P, Kennedy PT, Majzoub K, Asselah T. Hepatitis D virus: Improving virological knowledge to develop new treatments. Antiviral Res 2023; 209:105461. [PMID: 36396025 DOI: 10.1016/j.antiviral.2022.105461] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2022] [Revised: 10/21/2022] [Accepted: 11/05/2022] [Indexed: 11/16/2022]
Abstract
Hepatitis delta virus (HDV), a satellite of hepatitis B virus (HBV), possesses the smallest viral genome known to infect animals. HDV needs HBV surface protein for secretion and entry into target liver cells. However, HBV is dispensable for HDV genome amplification, as it relies almost exclusively on cellular host factors for replication. HBV/HDV co-infections affect over 12 million people worldwide and constitute the most severe form of viral hepatitis. Co-infected individuals are at higher risk of developing liver cirrhosis and hepatocellular carcinoma compared to HBV mono-infected patients. Bulevirtide, an entry inhibitor, was conditionally approved in July 2020 in the European Union for adult patients with chronic hepatitis delta (CHD) and compensated liver disease. There are several drugs in development, including lonafarnib and interferon lambda, with different modes of action. In this review, we detail our current fundamental knowledge of HDV lifecycle and review antiviral treatments under development against this virus, outlining their respective mechanisms-of-action. Finally, we describe the antiviral effect these compounds are showing in ongoing clinical trials, discussing their promise and potential pitfalls for managing HDV infected patients.
Collapse
Affiliation(s)
- Pierre Khalfi
- Institut de Génétique Moléculaire de Montpellier, University of Montpellier, CNRS-UMR 5535, Montpellier 34293 cedex 5, France
| | - Patrick T Kennedy
- The Blizard Institute, Queen Mary University of London, The Royal London Hospital, Barts Health NHS Trust, London, UK
| | - Karim Majzoub
- Institut de Génétique Moléculaire de Montpellier, University of Montpellier, CNRS-UMR 5535, Montpellier 34293 cedex 5, France.
| | - Tarik Asselah
- Université de Paris, Cité CRI, INSERM UMR 1149, Department of Hepatology, AP-HP Hôpital Beaujon, Clichy, France.
| |
Collapse
|
|
7
|
Asif B, Koh C. Hepatitis D virus (HDV): investigational therapeutic agents in clinical trials. Expert Opin Investig Drugs 2022; 31:905-920. [PMID: 34482769 PMCID: PMC11391510 DOI: 10.1080/13543784.2021.1977795] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2021] [Accepted: 09/03/2021] [Indexed: 12/24/2022]
Abstract
INTRODUCTION Chronic Hepatitis D virus (HDV) infection is a global disease leading to rapidly progressive liver disease with increased liver-related mortality and hepatocellular carcinoma. Therapies are minimally effective; however, an increased understanding of the HDV lifecycle has provided new potential drug targets. Thus, there is a growing number of investigational therapeutics under exploration for HDV with the potential for successful viral eradication. AREAS COVERED This review discusses the clinical impact of HDV infection and offers an in-depth look at the HDV life cycle. The authors examine current and new drug targets and the investigational therapies in clinical trials. The search strategy was based on PubMed database and clinicaltrials.gov which highlight the most up-to-date aspects of investigational therapies for chronic HDV infection.
Collapse
Affiliation(s)
- Bilal Asif
- Digestive Diseases Branch, National Institute of Diabetes & Digestive & Kidney Diseases, National Institutes of Health, Bethesda, USA
| | - Christopher Koh
- Liver Diseases Branch, National Institute of Diabetes & Digestive & Kidney Diseases, National Institutes of Health, Bethesda, USA
| |
Collapse
|
|
8
|
Role of Host-Mediated Post-Translational Modifications (PTMs) in RNA Virus Pathogenesis. Int J Mol Sci 2020; 22:ijms22010323. [PMID: 33396899 PMCID: PMC7796338 DOI: 10.3390/ijms22010323] [Citation(s) in RCA: 75] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2020] [Revised: 12/11/2020] [Accepted: 12/16/2020] [Indexed: 12/17/2022] Open
Abstract
Being opportunistic intracellular pathogens, viruses are dependent on the host for their replication. They hijack host cellular machinery for their replication and survival by targeting crucial cellular physiological pathways, including transcription, translation, immune pathways, and apoptosis. Immediately after translation, the host and viral proteins undergo a process called post-translational modification (PTM). PTMs of proteins involves the attachment of small proteins, carbohydrates/lipids, or chemical groups to the proteins and are crucial for the proteins’ functioning. During viral infection, host proteins utilize PTMs to control the virus replication, using strategies like activating immune response pathways, inhibiting viral protein synthesis, and ultimately eliminating the virus from the host. PTM of viral proteins increases solubility, enhances antigenicity and virulence properties. However, RNA viruses are devoid of enzymes capable of introducing PTMs to their proteins. Hence, they utilize the host PTM machinery to promote their survival. Proteins from viruses belonging to the family: Togaviridae, Flaviviridae, Retroviridae, and Coronaviridae such as chikungunya, dengue, zika, HIV, and coronavirus are a few that are well-known to be modified. This review discusses various host and virus-mediated PTMs that play a role in the outcome during the infection.
Collapse
|
|
9
|
Mammalian deltavirus without hepadnavirus coinfection in the neotropical rodent Proechimys semispinosus. Proc Natl Acad Sci U S A 2020; 117:17977-17983. [PMID: 32651267 PMCID: PMC7395443 DOI: 10.1073/pnas.2006750117] [Citation(s) in RCA: 41] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
Hepatitis delta virus (HDV) is a human hepatitis-causing RNA virus, unrelated to any other taxonomic group of RNA viruses. Its occurrence as a satellite virus of hepatitis B virus (HBV) is a singular case in animal virology for which no consensus evolutionary explanation exists. Here we present a mammalian deltavirus that does not occur in humans, identified in the neotropical rodent species Proechimys semispinosus The rodent deltavirus is highly distinct, showing a common ancestor with a recently described deltavirus in snakes. Reverse genetics based on a tandem minus-strand complementary DNA genome copy under the control of a cytomegalovirus (CMV) promoter confirms autonomous genome replication in transfected cells, with initiation of replication from the upstream genome copy. In contrast to HDV, a large delta antigen is not expressed and the farnesylation motif critical for HBV interaction is absent from a genome region that might correspond to a hypothetical rodent large delta antigen. Correspondingly, there is no evidence for coinfection with an HBV-related hepadnavirus based on virus detection and serology in any deltavirus-positive animal. No other coinfecting viruses were detected by RNA sequencing studies of 120 wild-caught animals that could serve as a potential helper virus. The presence of virus in blood and pronounced detection in reproductively active males suggest horizontal transmission linked to competitive behavior. Our study establishes a nonhuman, mammalian deltavirus that occurs as a horizontally transmitted infection, is potentially cleared by immune response, is not focused in the liver, and possibly does not require helper virus coinfection.
Collapse
|
|
10
|
Taylor JM. Infection by Hepatitis Delta Virus. Viruses 2020; 12:v12060648. [PMID: 32560053 PMCID: PMC7354607 DOI: 10.3390/v12060648] [Citation(s) in RCA: 33] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2020] [Revised: 06/10/2020] [Accepted: 06/12/2020] [Indexed: 02/06/2023] Open
Abstract
Hepatitis delta virus (HDV) and hepatitis B virus (HBV) are blood-borne viruses that infect human hepatocytes and cause significant liver disease. Infections with HBV are more damaging when there is a coinfection with HDV. The genomes and modes of replication of these two viruses are fundamentally different, except for the fact that, in nature, HDV replication is dependent upon the envelope proteins of HBV to achieve assembly and release of infectious virus particles, ones that use the same host cell receptor. This review focuses on what has been found of the various ways, natural and experimental, by which HDV particles can be assembled and released. This knowledge has implications for the prevention and treatment of HDV infections, and maybe for an understanding of the origin of HDV.
Collapse
Affiliation(s)
- John M Taylor
- Fox Chase Cancer Center, Philadelphia, PA 19111, USA
| |
Collapse
|
|
11
|
Targeting the Host for New Therapeutic Perspectives in Hepatitis D. J Clin Med 2020; 9:jcm9010222. [PMID: 31947588 PMCID: PMC7019876 DOI: 10.3390/jcm9010222] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2019] [Revised: 01/09/2020] [Accepted: 01/10/2020] [Indexed: 02/07/2023] Open
Abstract
Hepatitis D virus (HDV) is a small satellite virus of hepatitis B virus (HBV) requiring HBV infection to complete its life cycle. It has been recently estimated that 13% of chronic HBV infected patients (60 million) are co-infected with HDV. Chronic hepatitis D is the most severe form of viral hepatitis with the highest risk to develop cirrhosis and liver cancer. Current treatment is based on pegylated-interferon-alpha which rarely controls HDV infection and is complicated by serious side effects. The development of novel antiviral strategies based on host targeting agents has shown promising results in phase I/II clinical trials. This review summarizes HDV molecular virology and physiopathology as well as new therapeutic approaches targeting HDV host factors.
Collapse
|
|
12
|
Rasche A, Sander AL, Corman VM, Drexler JF. Evolutionary biology of human hepatitis viruses. J Hepatol 2019; 70:501-520. [PMID: 30472320 PMCID: PMC7114834 DOI: 10.1016/j.jhep.2018.11.010] [Citation(s) in RCA: 50] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/22/2018] [Revised: 11/09/2018] [Accepted: 11/10/2018] [Indexed: 02/06/2023]
Abstract
Hepatitis viruses are major threats to human health. During the last decade, highly diverse viruses related to human hepatitis viruses were found in animals other than primates. Herein, we describe both surprising conservation and striking differences of the unique biological properties and infection patterns of human hepatitis viruses and their animal homologues, including transmission routes, liver tropism, oncogenesis, chronicity, pathogenesis and envelopment. We discuss the potential for translation of newly discovered hepatitis viruses into preclinical animal models for drug testing, studies on pathogenesis and vaccine development. Finally, we re-evaluate the evolutionary origins of human hepatitis viruses and discuss the past and present zoonotic potential of their animal homologues.
Collapse
Affiliation(s)
- Andrea Rasche
- Charité-Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Institute of Virology, 10117 Berlin, Germany,German Center for Infection Research (DZIF), Germany
| | - Anna-Lena Sander
- Charité-Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Institute of Virology, 10117 Berlin, Germany
| | - Victor Max Corman
- Charité-Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Institute of Virology, 10117 Berlin, Germany,German Center for Infection Research (DZIF), Germany
| | - Jan Felix Drexler
- Charité-Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Institute of Virology, 10117 Berlin, Germany; German Center for Infection Research (DZIF), Germany.
| |
Collapse
|
|
13
|
Goodrum G, Pelchat M. Insight into the Contribution and Disruption of Host Processes during HDV Replication. Viruses 2018; 11:v11010021. [PMID: 30602655 PMCID: PMC6356607 DOI: 10.3390/v11010021] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2018] [Revised: 12/18/2018] [Accepted: 12/30/2018] [Indexed: 02/07/2023] Open
Abstract
Hepatitis delta virus (HDV) is unique among animal viruses. HDV is a satellite virus of the hepatitis B virus (HBV), however it shares no sequence similarity with its helper virus and replicates independently in infected cells. HDV is the smallest human pathogenic RNA virus and shares numerous characteristics with viroids. Like viroids, HDV has a circular RNA genome which adopts a rod-like secondary structure, possesses ribozyme domains, replicates in the nucleus of infected cells by redirecting host DNA-dependent RNA polymerases (RNAP), and relies heavily on host proteins for its replication due to its small size and limited protein coding capacity. These similarities suggest an evolutionary relationship between HDV and viroids, and information on HDV could allow a better understanding of viroids and might globally help understanding the pathogenesis and molecular biology of these subviral RNAs. In this review, we discuss the host involvement in HDV replication and its implication for HDV pathogenesis.
Collapse
Affiliation(s)
- Gabrielle Goodrum
- Department of Biochemistry, Microbiology and Immunology, Faculty of Medicine, University of Ottawa, Ottawa, ON K1H 8M5, Canada.
| | - Martin Pelchat
- Department of Biochemistry, Microbiology and Immunology, Faculty of Medicine, University of Ottawa, Ottawa, ON K1H 8M5, Canada.
| |
Collapse
|
|
14
|
Colagrossi L, Salpini R, Scutari R, Carioti L, Battisti A, Piermatteo L, Bertoli A, Fabeni L, Minichini C, Trimoulet P, Fleury H, Nebuloso E, De Cristofaro M, Cappiello G, Spanò A, Malagnino V, Mari T, Barlattani A, Iapadre N, Lichtner M, Mastroianni C, Lenci I, Pasquazzi C, De Sanctis GM, Galeota Lanza A, Stanzione M, Stornaiuolo G, Marignani M, Sarmati L, Andreoni M, Angelico M, Ceccherini-Silberstein F, Perno CF, Coppola N, Svicher V. HDV Can Constrain HBV Genetic Evolution in HBsAg: Implications for the Identification of Innovative Pharmacological Targets. Viruses 2018; 10:v10070363. [PMID: 29987240 PMCID: PMC6071122 DOI: 10.3390/v10070363] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2018] [Revised: 07/06/2018] [Accepted: 07/07/2018] [Indexed: 02/07/2023] Open
Abstract
Chronic HBV + HDV infection is associated with greater risk of liver fibrosis, earlier hepatic decompensation, and liver cirrhosis hepatocellular carcinoma compared to HBV mono-infection. However, to-date no direct anti-HDV drugs are available in clinical practice. Here, we identified conserved and variable regions in HBsAg and HDAg domains in HBV + HDV infection, a critical finding for the design of innovative therapeutic agents. The extent of amino-acid variability was measured by Shannon-Entropy (Sn) in HBsAg genotype-d sequences from 31 HBV + HDV infected and 62 HBV mono-infected patients (comparable for demographics and virological-parameters), and in 47 HDAg genotype-1 sequences. Positions with Sn = 0 were defined as conserved. The percentage of conserved HBsAg-positions was significantly higher in HBV + HDV infection than HBV mono-infection (p = 0.001). Results were confirmed after stratification for HBeAg-status and patients’ age. A Sn = 0 at specific positions in the C-terminus HBsAg were correlated with higher HDV-RNA, suggesting that conservation of these positions can preserve HDV-fitness. Conversely, HDAg was characterized by a lower percentage of conserved-residues than HBsAg (p < 0.001), indicating higher functional plasticity. Furthermore, specific HDAg-mutations were significantly correlated with higher HDV-RNA, suggesting a role in conferring HDV replicative-advantage. Among HDAg-domains, only the virus-assembly signal exhibited a high genetic conservation (75% of conserved-residues). In conclusion, HDV can constrain HBsAg genetic evolution to preserve its fitness. The identification of conserved regions in HDAg poses the basis for designing innovative targets against HDV-infection.
Collapse
Affiliation(s)
- Luna Colagrossi
- Department of Experimental Medicine and Surgery, Tor Vergata University, 00133 Rome, Italy.
| | - Romina Salpini
- Department of Experimental Medicine and Surgery, Tor Vergata University, 00133 Rome, Italy.
| | - Rossana Scutari
- Department of Experimental Medicine and Surgery, Tor Vergata University, 00133 Rome, Italy.
| | - Luca Carioti
- Department of Experimental Medicine and Surgery, Tor Vergata University, 00133 Rome, Italy.
| | - Arianna Battisti
- Department of Experimental Medicine and Surgery, Tor Vergata University, 00133 Rome, Italy.
| | - Lorenzo Piermatteo
- Department of Experimental Medicine and Surgery, Tor Vergata University, 00133 Rome, Italy.
| | - Ada Bertoli
- Department of Experimental Medicine and Surgery, Tor Vergata University, 00133 Rome, Italy.
| | - Lavinia Fabeni
- Department of Experimental Medicine and Surgery, Tor Vergata University, 00133 Rome, Italy.
| | - Carmine Minichini
- Department of Mental Health and Public Medicine, Section of Infectious Diseases, University of Campania L. Vanvitelli, 81100 Naples, Italy.
| | - Pascale Trimoulet
- Laboratoire de Virologie, Hôpital Pellegrin tripode, 33076 Bordeaux, France.
| | - Hervé Fleury
- Laboratoire de Virologie, Hôpital Pellegrin tripode, 33076 Bordeaux, France.
| | - Elena Nebuloso
- Unit of Microbiology, Sandro Pertini Hospital, 00157 Rome, Italy.
| | | | | | - Alberto Spanò
- Unit of Microbiology, Sandro Pertini Hospital, 00157 Rome, Italy.
| | - Vincenzo Malagnino
- Infectious Diseases Unit, Tor Vergata University Hospital, 00133 Rome, Italy.
| | - Terenzio Mari
- Hepatology Unit, Nuovo Regina Margherita Hospital, 00153 Rome, Italy.
| | - Angelo Barlattani
- Hepatology Unit, Nuovo Regina Margherita Hospital, 00153 Rome, Italy.
| | - Nerio Iapadre
- Infectious Diseases Unit, San Salvatore Hospital, 67100 L'Aquila, Italy.
| | - Miriam Lichtner
- Department of Public Health and Infectious Diseases, Sapienza University, 00185 Rome, Italy.
| | - Claudio Mastroianni
- Department of Public Health and Infectious Diseases, Sapienza University, 00185 Rome, Italy.
| | - Ilaria Lenci
- Hepatology Unit, Tor Vergata University Hospital, 00133 Rome, Italy.
| | | | | | | | - Maria Stanzione
- Department of Internal Medicine, University of Campania L. Vanvitelli, Viral Unit, 81100 Naples, Italy.
| | - Gianfranca Stornaiuolo
- Department of Internal Medicine, University of Campania L. Vanvitelli, Viral Unit, 81100 Naples, Italy.
| | | | - Loredana Sarmati
- Infectious Diseases Unit, Tor Vergata University Hospital, 00133 Rome, Italy.
| | - Massimo Andreoni
- Infectious Diseases Unit, Tor Vergata University Hospital, 00133 Rome, Italy.
| | - Mario Angelico
- Hepatology Unit, Tor Vergata University Hospital, 00133 Rome, Italy.
| | | | - Carlo-Federico Perno
- Department of Experimental Medicine and Surgery, Tor Vergata University, 00133 Rome, Italy.
- Haematology and Oncohematology, University of Milan, 20122 Milan, Italy.
| | - Nicola Coppola
- Department of Mental Health and Public Medicine, Section of Infectious Diseases, University of Campania L. Vanvitelli, 81100 Naples, Italy.
| | - Valentina Svicher
- Department of Experimental Medicine and Surgery, Tor Vergata University, 00133 Rome, Italy.
| |
Collapse
|
|
15
|
Jiang H, Zhang X, Chen X, Aramsangtienchai P, Tong Z, Lin H. Protein Lipidation: Occurrence, Mechanisms, Biological Functions, and Enabling Technologies. Chem Rev 2018; 118:919-988. [PMID: 29292991 DOI: 10.1021/acs.chemrev.6b00750] [Citation(s) in RCA: 333] [Impact Index Per Article: 47.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
Protein lipidation, including cysteine prenylation, N-terminal glycine myristoylation, cysteine palmitoylation, and serine and lysine fatty acylation, occurs in many proteins in eukaryotic cells and regulates numerous biological pathways, such as membrane trafficking, protein secretion, signal transduction, and apoptosis. We provide a comprehensive review of protein lipidation, including descriptions of proteins known to be modified and the functions of the modifications, the enzymes that control them, and the tools and technologies developed to study them. We also highlight key questions about protein lipidation that remain to be answered, the challenges associated with answering such questions, and possible solutions to overcome these challenges.
Collapse
Affiliation(s)
- Hong Jiang
- Howard Hughes Medical Institute, Department of Chemistry and Chemical Biology, Cornell University , Ithaca, New York 14853, United States
| | - Xiaoyu Zhang
- Howard Hughes Medical Institute, Department of Chemistry and Chemical Biology, Cornell University , Ithaca, New York 14853, United States
| | - Xiao Chen
- Howard Hughes Medical Institute, Department of Chemistry and Chemical Biology, Cornell University , Ithaca, New York 14853, United States
| | - Pornpun Aramsangtienchai
- Howard Hughes Medical Institute, Department of Chemistry and Chemical Biology, Cornell University , Ithaca, New York 14853, United States
| | - Zhen Tong
- Howard Hughes Medical Institute, Department of Chemistry and Chemical Biology, Cornell University , Ithaca, New York 14853, United States
| | - Hening Lin
- Howard Hughes Medical Institute, Department of Chemistry and Chemical Biology, Cornell University , Ithaca, New York 14853, United States
| |
Collapse
|
|
16
|
Marakasova ES, Eisenhaber B, Maurer-Stroh S, Eisenhaber F, Baranova A. Prenylation of viral proteins by enzymes of the host: Virus-driven rationale for therapy with statins and FT/GGT1 inhibitors. Bioessays 2017; 39. [DOI: 10.1002/bies.201700014] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Affiliation(s)
| | - Birgit Eisenhaber
- Bioinformatics Institute; Agency for Science; Technology and Research Singapore
| | - Sebastian Maurer-Stroh
- Bioinformatics Institute; Agency for Science; Technology and Research Singapore
- Department of Biological Sciences; National University Singapore; Singapore
| | - Frank Eisenhaber
- Bioinformatics Institute; Agency for Science; Technology and Research Singapore
- Department of Biological Sciences; National University Singapore; Singapore
- School of Computer Engineering; Nanyang Technological University; Singapore
| | - Ancha Baranova
- School of Systems Biology; George Mason University; Fairfax VA USA
- Research Centre for Medical Genetics; Russian Academy of Medical Sciences; Moscow Russia
| |
Collapse
|
|
17
|
Lempp FA, Urban S. Hepatitis Delta Virus: Replication Strategy and Upcoming Therapeutic Options for a Neglected Human Pathogen. Viruses 2017; 9:E172. [PMID: 28677645 PMCID: PMC5537664 DOI: 10.3390/v9070172] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2017] [Revised: 06/28/2017] [Accepted: 06/29/2017] [Indexed: 12/15/2022] Open
Abstract
The human Hepatitis Delta Virus (HDV) is unique among all viral pathogens. Encoding only one protein (Hepatitis Delta Antigen; HDAg) within its viroid-like self-complementary RNA, HDV constitutes the smallest known virus in the animal kingdom. To disseminate in its host, HDV depends on a helper virus, the human Hepatitis B virus (HBV), which provides the envelope proteins required for HDV assembly. HDV affects an estimated 15-20 million out of the 240 million chronic HBV-carriers and disperses unequally in disparate geographical regions of the world. The disease it causes (chronic Hepatitis D) presents as the most severe form of viral hepatitis, leading to accelerated progression of liver dysfunction including cirrhosis and hepatocellular carcinoma and a high mortality rate. The lack of approved drugs interfering with specific steps of HDV replication poses a high burden for gaining insights into the molecular biology of the virus and, consequently, the development of specific novel medications that resiliently control HDV replication or, in the best case, functionally cure HDV infection or HBV/HDV co-infection. This review summarizes our current knowledge of HBV molecular biology, presents an update on novel cell culture and animal models to study the virus and provides updates on the clinical development of the three developmental drugs Lonafarnib, REP2139-Ca and Myrcludex B.
Collapse
Affiliation(s)
- Florian A Lempp
- Department of Infectious Diseases, Molecular Virology, Heidelberg University, Im Neuenheimer Feld 345, 69120 Heidelberg, Germany.
- German Centre for Infection Research (DZIF), Partner Site Heidelberg, 69120 Heidelberg, Germany.
| | - Stephan Urban
- Department of Infectious Diseases, Molecular Virology, Heidelberg University, Im Neuenheimer Feld 345, 69120 Heidelberg, Germany.
- German Centre for Infection Research (DZIF), Partner Site Heidelberg, 69120 Heidelberg, Germany.
| |
Collapse
|
|
18
|
Lempp FA, Ni Y, Urban S. Hepatitis delta virus: insights into a peculiar pathogen and novel treatment options. Nat Rev Gastroenterol Hepatol 2016; 13:580-9. [PMID: 27534692 DOI: 10.1038/nrgastro.2016.126] [Citation(s) in RCA: 121] [Impact Index Per Article: 13.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Chronic hepatitis D is the most severe form of viral hepatitis, affecting ∼20 million HBV-infected people worldwide. The causative agent, hepatitis delta virus (HDV), is a unique human pathogen: it is the smallest known virus; it depends on HBV to disseminate its viroid-like RNA; it encodes only one protein (HDAg), which has both structural and regulatory functions; and it replicates using predominantly host proteins. The failure of HBV-specific nucleoside analogues to suppress the HBV helper function, and the limitations of experimental systems to study the HDV life cycle, have impeded the development of HDV-specific drugs. Thus, the only clinical regimen for HDV is IFNα, which shows some efficacy but long-term virological responses are rare. Insights into the receptor-mediated entry of HDV, and the observation that HDV assembly requires farnesyltransferase, have enabled novel therapeutic strategies to be developed. Interference with entry, for example through blockade of the HBV-HDV-specific receptor sodium/taurocholate cotransporting polypeptide NTCP by Myrcludex B, and inhibition of assembly by blockade of farnesyltransferase using lonafarnib or nucleic acid polymers such as REP 2139-Ca, have shown promising results in phase II studies. In this Review, we summarize our knowledge of HDV epidemiology, pathogenesis and molecular biology, with a particular emphasis on possible future developments.
Collapse
Affiliation(s)
- Florian A Lempp
- Department of Infectious Diseases, Molecular Virology, University Hospital Heidelberg, Im Neuenheimer Feld 345, 69120 Heidelberg, Germany
| | - Yi Ni
- Department of Infectious Diseases, Molecular Virology, University Hospital Heidelberg, Im Neuenheimer Feld 345, 69120 Heidelberg, Germany.,German Center for Infection Research (DZIF), Heidelberg Partner Site, Im Neuenheimer Feld 324, 69120 Heidelberg, Germany
| | - Stephan Urban
- Department of Infectious Diseases, Molecular Virology, University Hospital Heidelberg, Im Neuenheimer Feld 345, 69120 Heidelberg, Germany.,German Center for Infection Research (DZIF), Heidelberg Partner Site, Im Neuenheimer Feld 324, 69120 Heidelberg, Germany
| |
Collapse
|
|
19
|
Sureau C, Negro F. The hepatitis delta virus: Replication and pathogenesis. J Hepatol 2016; 64:S102-S116. [PMID: 27084031 DOI: 10.1016/j.jhep.2016.02.013] [Citation(s) in RCA: 196] [Impact Index Per Article: 21.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/10/2015] [Revised: 02/01/2016] [Accepted: 02/10/2016] [Indexed: 02/06/2023]
Abstract
Hepatitis delta virus (HDV) is a defective virus and a satellite of the hepatitis B virus (HBV). Its RNA genome is unique among animal viruses, but it shares common features with some plant viroids, including a replication mechanism that uses a host RNA polymerase. In infected cells, HDV genome replication and formation of a nucleocapsid-like ribonucleoprotein (RNP) are independent of HBV. But the RNP cannot exit, and therefore propagate, in the absence of HBV, as the latter supplies the propagation mechanism, from coating the HDV RNP with the HBV envelope proteins for cell egress to delivery of the HDV virions to the human hepatocyte target. HDV is therefore an obligate satellite of HBV; it infects humans either concomitantly with HBV or after HBV infection. HDV affects an estimated 15 to 20 million individuals worldwide, and the clinical significance of HDV infection is more severe forms of viral hepatitis--acute or chronic--, and a higher risk of developing cirrhosis and hepatocellular carcinoma in comparison to HBV monoinfection. This review covers molecular aspects of HDV replication cycle, including its interaction with the helper HBV and the pathogenesis of infection in humans.
Collapse
Affiliation(s)
- Camille Sureau
- Molecular Virology laboratory, Institut National de la Transfusion Sanguine (INTS), CNRS INSERM U1134, Paris, France.
| | - Francesco Negro
- Division of Gastroenterology and Hepatology, University Hospitals, Geneva, Switzerland; Division of Clinical Pathology, University Hospitals, Geneva, Switzerland.
| |
Collapse
|
|
20
|
|
|
21
|
Cunha C, Tavanez JP, Gudima S. Hepatitis delta virus: A fascinating and neglected pathogen. World J Virol 2015; 4:313-322. [PMID: 26568914 PMCID: PMC4641224 DOI: 10.5501/wjv.v4.i4.313] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/29/2015] [Revised: 08/21/2015] [Accepted: 10/27/2015] [Indexed: 02/05/2023] Open
Abstract
Hepatitis delta virus (HDV) is the etiologic agent of the most severe form of virus hepatitis in humans. Sharing some structural and functional properties with plant viroids, the HDV RNA contains a single open reading frame coding for the only virus protein, the Delta antigen. A number of unique features, including ribozyme activity, RNA editing, rolling-circle RNA replication, and redirection for a RNA template of host DNA-dependent RNA polymerase II, make this small pathogen an excellent model to study virus-cell interactions and RNA biology. Treatment options for chronic hepatitis Delta are scarce and ineffective. The disease burden is perhaps largely underestimated making the search for new, specific drugs, targets, and treatment strategies an important public health challenge. In this review we address the main features of virus structure, replication, and interaction with the host. Virus pathogenicity and current treatment options are discussed in the light of recent developments.
Collapse
|
|
22
|
Abstract
This work reviews specific related aspects of hepatitis delta virus (HDV) reproduction, including virion structure, the RNA genome, the mode of genome replication, the delta antigens, and the assembly of HDV using the envelope proteins of its helper virus, hepatitis B virus (HBV). These topics are considered with perspectives ranging from a history of discovery through to still-unsolved problems. HDV evolution, virus entry, and associated pathogenic potential and treatment of infections are considered in other articles in this collection.
Collapse
Affiliation(s)
- John M Taylor
- Fox Chase Cancer Center, Philadelphia, Pennsylvania 19111
| |
Collapse
|
|
23
|
Tate EW, Kalesh KA, Lanyon-Hogg T, Storck EM, Thinon E. Global profiling of protein lipidation using chemical proteomic technologies. Curr Opin Chem Biol 2015; 24:48-57. [PMID: 25461723 PMCID: PMC4319709 DOI: 10.1016/j.cbpa.2014.10.016] [Citation(s) in RCA: 84] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2014] [Accepted: 10/23/2014] [Indexed: 01/22/2023]
Abstract
Protein lipidation is unique amongst post-translational modifications (PTMs) in enabling direct interaction with cell membranes, and is found in every form of life. Lipidation is important in normal function and in disease, but its intricate interplay with disease context presents a challenging for drug development. Global whole-proteome profiling of protein lipidation lies beyond the range of standard methods, but is well-suited to metabolic tagging with small 'clickable' chemical reporters that do not disrupt metabolism and function; chemoselective reactions are then used to add multifunctional labels exclusively to tagged-lipidated proteins. This chemical proteomic technology has opened up the first quantitative whole-proteome studies of the known major classes of protein lipidation, and the first insights into their full scope in vivo.
Collapse
Affiliation(s)
- Edward W Tate
- Department of Chemistry, Imperial College London, Exhibition Road, London SW7 2AZ, UK.
| | - Karunakaran A Kalesh
- Department of Chemistry, Imperial College London, Exhibition Road, London SW7 2AZ, UK
| | - Thomas Lanyon-Hogg
- Department of Chemistry, Imperial College London, Exhibition Road, London SW7 2AZ, UK
| | - Elisabeth M Storck
- Department of Chemistry, Imperial College London, Exhibition Road, London SW7 2AZ, UK
| | | |
Collapse
|
|
24
|
Hepatitis delta virus: a peculiar virus. Adv Virol 2013; 2013:560105. [PMID: 24198831 PMCID: PMC3807834 DOI: 10.1155/2013/560105] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2013] [Revised: 08/29/2013] [Accepted: 08/29/2013] [Indexed: 02/07/2023] Open
Abstract
The hepatitis delta virus (HDV) is distributed worldwide and related to the most severe form of viral hepatitis. HDV is a satellite RNA virus dependent on hepatitis B surface antigens to assemble its envelope and thus form new virions and propagate infection. HDV has a small 1.7 Kb genome making it the smallest known human virus. This deceivingly simple virus has unique biological features and many aspects of its life cycle remain elusive. The present review endeavors to gather the available information on HDV epidemiology and clinical features as well as HDV biology.
Collapse
|
|
25
|
Prenylome profiling reveals S-farnesylation is crucial for membrane targeting and antiviral activity of ZAP long-isoform. Proc Natl Acad Sci U S A 2013; 110:11085-90. [PMID: 23776219 DOI: 10.1073/pnas.1302564110] [Citation(s) in RCA: 106] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
S-prenylation is an important lipid modification that targets proteins to membranes for cell signaling and vesicle trafficking in eukaryotes. As S-prenylated proteins are often key effectors for oncogenesis, congenital disorders, and microbial pathogenesis, robust proteomic methods are still needed to biochemically characterize these lipidated proteins in specific cell types and disease states. Here, we report that bioorthogonal proteomics of macrophages with an improved alkyne-isoprenoid chemical reporter enables large-scale profiling of prenylated proteins, as well as the discovery of unannotated lipidated proteins such as isoform-specific S-farnesylation of zinc-finger antiviral protein (ZAP). Notably, S-farnesylation was crucial for targeting the long-isoform of ZAP (ZAPL/PARP-13.1/zc3hav1) to endolysosomes and enhancing the antiviral activity of this immune effector. These studies demonstrate the utility of isoprenoid chemical reporters for proteomic analysis of prenylated proteins and reveal a role for protein prenylation in host defense against viral infections.
Collapse
|
|
26
|
Ochocki JD, Distefano MD. Prenyltransferase Inhibitors: Treating Human Ailments from Cancer to Parasitic Infections. MEDCHEMCOMM 2013; 4:476-492. [PMID: 25530833 DOI: 10.1039/c2md20299a] [Citation(s) in RCA: 50] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
The posttranslational modification of protein prenylation is a covalent lipid modification on the C-terminus of substrate proteins that serves to enhance membrane affinity. Oncogenic proteins such as Ras have this modification and significant effort has been placed into developing inhibitors of the prenyltransferase enzymes for clinical therapy. In addition to cancer therapy, prenyltransferase inhibitors have begun to find important therapeutic uses in other diseases, including progeria, hepatitis C and D, parasitic infections, and other maladies. This review will trace the evolution of prenyltransferase inhibitors from their initial use as cancer therapeutics to their expanded applications for other diseases.
Collapse
Affiliation(s)
- Joshua D Ochocki
- Department of Chemistry, University of Minnesota, Minneapolis, MN 55455 (USA)
| | - Mark D Distefano
- Department of Chemistry, University of Minnesota, Minneapolis, MN 55455 (USA)
| |
Collapse
|
|
27
|
Dastgerdi ES, Herbers U, Tacke F. Molecular and clinical aspects of hepatitis D virus infections. World J Virol 2012; 1:71-8. [PMID: 24175212 PMCID: PMC3782269 DOI: 10.5501/wjv.v1.i3.71] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/19/2011] [Revised: 05/12/2012] [Accepted: 05/20/2012] [Indexed: 02/05/2023] Open
Abstract
Hepatitis D virus (HDV) is a defective virus with circular, single-stranded genomic RNA which needs hepatitis B virus (HBV) as a helper virus for virion assembly and infectivity. HDV virions are composed of a circular shape HDV RNA and two types of viral proteins, small and large HDAgs, surrounded by HBV surface antigen (HBsAg). The RNA polymerase II from infected hepatocytes is responsible for synthesizing RNAs with positive and negative polarities for HDV, as the virus does not code any enzyme to replicate its genome. HDV occurs as co-infection or super-infection in up to 5% of HBsAg carriers. A recent multi-center study highlighted that pegylated interferon α-2a (PEG-IFN) is currently the only treatment option for delta hepatitis. Nucleotide/nucleoside analogues, which are effective against HBV, have no relevant effects on HDV. However, additional clinical trials combining PEG-IFN and tenofovir are currently ongoing. The molecular interactions between HDV and HBV are incompletely understood. Despite fluctuating patterns of HBV viral load in the presence of HDV in patients, several observations indicate that HDV has suppressive effects on HBV replication, and even in triple infections with HDV, HBV and HCV, replication of both concomitant viruses can be reduced. Additional molecular virology studies are warranted to clarify how HDV interacts with the helper virus and which key cellular pathways are used by both viruses. Further clinical trials are underway to optimize treatment strategies for delta hepatitis.
Collapse
Affiliation(s)
- Elham Shirvani Dastgerdi
- Elham Shirvani Dastgerdi, Ulf Herbers, Frank Tacke, Department of Medicine III, RWTH-University Hospital Aachen, Pauwelsstrasse 30, 52074 Aachen, Germany
| | | | | |
Collapse
|
|
28
|
Interaction of host cellular proteins with components of the hepatitis delta virus. Viruses 2010; 2:189-212. [PMID: 21994607 PMCID: PMC3185554 DOI: 10.3390/v2010189] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2009] [Revised: 01/13/2010] [Accepted: 01/14/2010] [Indexed: 12/18/2022] Open
Abstract
The hepatitis delta virus (HDV) is the smallest known RNA pathogen capable of propagation in the human host and causes substantial global morbidity and mortality. Due to its small size and limited protein coding capacity, HDV is exquisitely reliant upon host cellular proteins to facilitate its transcription and replication. Remarkably, HDV does not encode an RNA-dependent RNA polymerase which is traditionally required to catalyze RNA-templated RNA synthesis. Furthermore, HDV lacks enzymes responsible for post-transcriptional and -translational modification, processes which are integral to the HDV life cycle. This review summarizes the known HDV-interacting proteins and discusses their significance in HDV biology.
Collapse
|
|
29
|
Protein Prenylation: An (Almost) Comprehensive Overview on Discovery History, Enzymology, and Significance in Physiology and Disease. MONATSHEFTE FUR CHEMIE 2006. [DOI: 10.1007/s00706-006-0534-9] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
|
|
30
|
Abstract
The hepatitis delta virus (HDV) is a subviral agent that utilizes the envelope proteins of the hepatitis B virus (HBV) for propagation. When introduced into permissive cells, the HDV RNA genome replicates and associates with multiple copies of the HDV-encoded proteins to assemble a ribonucleoprotein (RNP) complex. The mechanism necessary to export the RNP from the cell is provided by the HBV envelope proteins, which have the capacity to assemble lipoprotein vesicles that bud into the lumen of a pre-Golgi compartment before being secreted. In addition to allowing the release of the HDV RNP, the HBV envelope proteins also provide a means for its targeting to an uninfected cell, thereby ensuring the spread of HDV. This chapter covers the molecular aspects of the HBV envelope protein functions in the HDV replication cycle, in particular the activity of the small envelope protein in RNP export and the function of the large envelope protein at viral entry.
Collapse
Affiliation(s)
- C Sureau
- Laboratoire de Virologie Moléculaire, Institut National de la Transfusion Sanguine, Paris, France.
| |
Collapse
|
|
31
|
Abstract
HDV replicates its circular RNA genome using a double rolling-circle mechanism and transcribes a hepatitis delta antigen-encodeing mRNA from the same RNA template during its life cycle. Both processes are carried out by RNA-dependent RNA synthesis despite the fact that HDV does not encode an RNA-dependent RNA polymerase (RdRP). Cellular RNA polymerase II has long been implicated in these processes. Recent findings, however, have shown that the syntheses of genomic and antigenomic RNA strands have different metabolic requirements, including sensitives to alpha-amanitin and the site of synthesis. Evidence is summarized here for the involvement of other cellular polymerases, probably pol I, in the synthesis of antigenomic RNA strand. The ability of mammalian cells to replicate HDV RNA implies that RNA-dependent RNA synthesis was preserved throughout evolution.
Collapse
Affiliation(s)
- T B Macnaughton
- Department of Molecular Microbiology and Immunology, Keck School of Medicine, University of Southern California, Los Angeles 90033, USA
| | | |
Collapse
|
|
32
|
Huang WH, Chen CW, Wu HL, Chen PJ. Post-translational modification of delta antigen of hepatitis D virus. Curr Top Microbiol Immunol 2006; 307:91-112. [PMID: 16903222 DOI: 10.1007/3-540-29802-9_5] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
The hepatitis delta virus (HDV) genome has only one open reading frame, which encodes the viral small delta antigen. After RNA editing, the same open reading frame is extended 19 amino acids at the carboxyl terminus and encodes the large delta antigen. These two viral proteins escort the HDV genome through different cellular compartments for the complicated phases of replication, transcription and, eventually, the formation of progeny virions. To orchestrate these events, the delta antigens have to take distinct cues to traffic to the right compartments and make correct molecular contacts. In eukaryotes, post-translational modification (PTM) is a major mechanism of dictating the multiple functions of a single protein. Multiple PTMs, including phosphorylation, isoprenylation, acetylation, and methylation, have been identified on hepatitis delta antigens. In this chapter we review these PTMs and discuss their functions in regulating and coordinating the life cycle of HDV.
Collapse
Affiliation(s)
- W H Huang
- Graduate Institute of Clinical Medicine, College of Medicine, National Taiwan University, and Hepatitis Research Center, National Taiwan University Hospital, Taipei
| | | | | | | |
Collapse
|
|
33
|
Lane KT, Beese LS. Thematic review series: lipid posttranslational modifications. Structural biology of protein farnesyltransferase and geranylgeranyltransferase type I. J Lipid Res 2006; 47:681-99. [PMID: 16477080 DOI: 10.1194/jlr.r600002-jlr200] [Citation(s) in RCA: 190] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
More than 100 proteins necessary for eukaryotic cell growth, differentiation, and morphology require posttranslational modification by the covalent attachment of an isoprenoid lipid (prenylation). Prenylated proteins include members of the Ras, Rab, and Rho families, lamins, CENPE and CENPF, and the gamma subunit of many small heterotrimeric G proteins. This modification is catalyzed by the protein prenyltransferases: protein farnesyltransferase (FTase), protein geranylgeranyltransferase type I (GGTase-I), and GGTase-II (or RabGGTase). In this review, we examine the structural biology of FTase and GGTase-I (the CaaX prenyltransferases) to establish a framework for understanding the molecular basis of substrate specificity and mechanism. These enzymes have been identified in a number of species, including mammals, fungi, plants, and protists. Prenyltransferase structures include complexes that represent the major steps along the reaction path, as well as a number of complexes with clinically relevant inhibitors. Such complexes may assist in the design of inhibitors that could lead to treatments for cancer, viral infection, and a number of deadly parasitic diseases.
Collapse
Affiliation(s)
- Kimberly T Lane
- Department of Biochemistry, Duke University Medical Center, Durham, NC 27710, USA
| | | |
Collapse
|
|
34
|
O'Malley B, Lazinski DW. Roles of carboxyl-terminal and farnesylated residues in the functions of the large hepatitis delta antigen. J Virol 2005; 79:1142-53. [PMID: 15613342 PMCID: PMC538544 DOI: 10.1128/jvi.79.2.1142-1153.2005] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
The large hepatitis delta antigen (HDAg-L) mediates hepatitis delta virus (HDV) assembly and inhibits HDV RNA replication. Farnesylation of the cysteine residue within the HDAg-L carboxyl terminus is required for both functions. Here, HDAg-L proteins from different HDV genotypes and genotype chimeric proteins were analyzed for their ability to incorporate into virus-like particles (VLPs). Observed differences in efficiency of VLP incorporation could be attributed to genotype-specific differences within the HDAg-L carboxyl terminus. Using a novel assay to quantify the extent of HDAg-L farnesylation, we found that genotype 3 HDAg-L was inefficiently farnesylated when expressed in the absence of the small hepatitis delta antigen (HDAg-S). However, as the intracellular ratio of HDAg-S to HDAg-L was increased, so too was the extent of HDAg-L farnesylation for all three genotypes. Single point mutations within the carboxyl terminus of HDAg-L were screened, and three mutants that severely inhibited assembly without affecting farnesylation were identified. The observed assembly defects persisted under conditions where the mutants were known to have access to the site of VLP assembly. Therefore, the corresponding residues within the wild-type protein are likely required for direct interaction with viral envelope proteins. Finally, it was observed that when HDAg-S was artificially myristoylated, it could efficiently inhibit HDV RNA replication. Hence, a general association with membranes enables HDAg to inhibit replication. In contrast, although myristoylated HDAg-S was incorporated into VLPs far more efficiently than HDAg-S or nonfarnesylated HDAg-L, it was incorporated far less efficiently than wild-type HDAg-L; thus, farnesylation was required for efficient assembly.
Collapse
Affiliation(s)
- Brendan O'Malley
- Department of Molecular Biology and Microbiology, Tufts University School of Medicine, 150 Harrison Ave., Boston, MA 02111, USA
| | | |
Collapse
|
|
35
|
Reid TS, Terry KL, Casey PJ, Beese LS. Crystallographic Analysis of CaaX Prenyltransferases Complexed with Substrates Defines Rules of Protein Substrate Selectivity. J Mol Biol 2004; 343:417-33. [PMID: 15451670 DOI: 10.1016/j.jmb.2004.08.056] [Citation(s) in RCA: 196] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2004] [Revised: 08/13/2004] [Accepted: 08/18/2004] [Indexed: 11/26/2022]
Abstract
Post-translational modifications are essential for the proper function of many proteins in the cell. The attachment of an isoprenoid lipid (a process termed prenylation) by protein farnesyltransferase (FTase) or geranylgeranyltransferase type I (GGTase-I) is essential for the function of many signal transduction proteins involved in growth, differentiation, and oncogenesis. FTase and GGTase-I (also called the CaaX prenyltransferases) recognize protein substrates with a C-terminal tetrapeptide recognition motif called the Ca1a2X box. These enzymes possess distinct but overlapping protein substrate specificity that is determined primarily by the sequence identity of the Ca1a2X motif. To determine how the identity of the Ca1a2X motif residues and sequence upstream of this motif affect substrate binding, we have solved crystal structures of FTase and GGTase-I complexed with a total of eight cognate and cross-reactive substrate peptides, including those derived from the C termini of the oncoproteins K-Ras4B, H-Ras and TC21. These structures suggest that all peptide substrates adopt a common binding mode in the FTase and GGTase-I active site. Unexpectedly, while the X residue of the Ca1a2X motif binds in the same location for all GGTase-I substrates, the X residue of FTase substrates can bind in one of two different sites. Together, these structures outline a series of rules that govern substrate peptide selectivity; these rules were utilized to classify known protein substrates of CaaX prenyltransferases and to generate a list of hypothetical substrates within the human genome.
Collapse
Affiliation(s)
- T Scott Reid
- Department of Biochemistry, Duke University Medical Center, Durham, NC 27710, USA
| | | | | | | |
Collapse
|
|
36
|
Cornillez-Ty CT, Lazinski DW. Determination of the multimerization state of the hepatitis delta virus antigens in vivo. J Virol 2003; 77:10314-26. [PMID: 12970416 PMCID: PMC228508 DOI: 10.1128/jvi.77.19.10314-10326.2003] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
Hepatitis delta virus expresses two essential proteins, the small and large delta antigens, and both are required for viral propagation. Proper function of each protein depends on the presence of a common amino-terminal multimerization domain. A crystal structure, solved using a peptide fragment that contained residues 12 to 60, depicts the formation of an octameric ring composed of antiparallel coiled-coil dimers. Because this crystal structure was solved for only a fragment of the delta antigens, it is unknown whether octamers actually form in vivo at physiological protein concentrations and in the context of either intact delta antigen. To test the relevance of the octameric structure, we developed a new method to probe coiled-coil structures in vivo. We generated a panel of mutants containing cysteine substitutions at strategic locations within the predicted monomer-monomer interface and the dimer-dimer interface. Since the small delta antigen contains no cysteine residues, treatment of cell extracts with a mild oxidizing reagent was expected to induce disulfide bond formation only when the appropriate pairs of cysteine substitution mutants were coexpressed. We indeed found that, in vivo, both the small and large delta antigens assembled as antiparallel coiled-coil dimers. Likewise, we found that both proteins could assume an octameric quaternary structure in vivo. Finally, during the course of these experiments, we found that unprenylated large delta antigen molecules could be disulfide cross-linked via the sole cysteine residue located within the carboxy terminus. Therefore, in vivo, the C terminus likely provides an additional site of protein-protein interaction for the large delta antigen.
Collapse
Affiliation(s)
- Cromwell T Cornillez-Ty
- Department of Molecular Biology and Microbiology, Tufts University School of Medicine, Boston, Massachusetts 02111, USA
| | | |
Collapse
|
|
37
|
Bordier BB, Ohkanda J, Liu P, Lee SY, Salazar FH, Marion PL, Ohashi K, Meuse L, Kay MA, Casey JL, Sebti SM, Hamilton AD, Glenn JS. In vivo antiviral efficacy of prenylation inhibitors against hepatitis delta virus. J Clin Invest 2003. [PMID: 12897208 DOI: 10.1172/jci17704112/3/407] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
Hepatitis delta virus (HDV) can dramatically worsen liver disease in patients coinfected with hepatitis B virus (HBV). No effective medical therapy exists for HDV. The HDV envelope requires HBV surface antigen proteins provided by HBV. Once inside a cell, however, HDV can replicate its genome in the absence of any HBV gene products. In vitro, HDV virion assembly is critically dependent on prenyl lipid modification, or prenylation, of its nucleocapsid-like protein large delta antigen. To overcome limitations of current animal models and to test the hypothesis that pharmacologic prenylation inhibition can prevent the production of HDV virions in vivo, we established a convenient mouse-based model of HDV infection capable of yielding viremia. Such mice were then treated with the prenylation inhibitors FTI-277 and FTI-2153. Both agents were highly effective at clearing HDV viremia. As expected, HDV inhibition exhibited duration-of-treatment dependence. These results provide the first preclinical data supporting the in vivo efficacy of prenylation inhibition as a novel antiviral therapy with potential application to HDV and a wide variety of other viruses.
Collapse
Affiliation(s)
- Bruno B Bordier
- Division of Gastroenterology and Hepatology, Stanford University School of Medicine, Palo Alto, California 94305, USA
| | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
|
38
|
Bordier BB, Ohkanda J, Liu P, Lee SY, Salazar FH, Marion PL, Ohashi K, Meuse L, Kay MA, Casey JL, Sebti SM, Hamilton AD, Glenn JS. In vivo antiviral efficacy of prenylation inhibitors against hepatitis delta virus. J Clin Invest 2003. [PMID: 12897208 DOI: 10.1172/jci200317704] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
Hepatitis delta virus (HDV) can dramatically worsen liver disease in patients coinfected with hepatitis B virus (HBV). No effective medical therapy exists for HDV. The HDV envelope requires HBV surface antigen proteins provided by HBV. Once inside a cell, however, HDV can replicate its genome in the absence of any HBV gene products. In vitro, HDV virion assembly is critically dependent on prenyl lipid modification, or prenylation, of its nucleocapsid-like protein large delta antigen. To overcome limitations of current animal models and to test the hypothesis that pharmacologic prenylation inhibition can prevent the production of HDV virions in vivo, we established a convenient mouse-based model of HDV infection capable of yielding viremia. Such mice were then treated with the prenylation inhibitors FTI-277 and FTI-2153. Both agents were highly effective at clearing HDV viremia. As expected, HDV inhibition exhibited duration-of-treatment dependence. These results provide the first preclinical data supporting the in vivo efficacy of prenylation inhibition as a novel antiviral therapy with potential application to HDV and a wide variety of other viruses.
Collapse
Affiliation(s)
- Bruno B Bordier
- Division of Gastroenterology and Hepatology, Stanford University School of Medicine, Palo Alto, California 94305, USA
| | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
|
39
|
Bordier BB, Ohkanda J, Liu P, Lee SY, Salazar FH, Marion PL, Ohashi K, Meuse L, Kay MA, Casey JL, Sebti SM, Hamilton AD, Glenn JS. In vivo antiviral efficacy of prenylation inhibitors against hepatitis delta virus. J Clin Invest 2003; 112:407-14. [PMID: 12897208 PMCID: PMC166292 DOI: 10.1172/jci17704] [Citation(s) in RCA: 146] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2002] [Accepted: 05/06/2003] [Indexed: 12/18/2022] Open
Abstract
Hepatitis delta virus (HDV) can dramatically worsen liver disease in patients coinfected with hepatitis B virus (HBV). No effective medical therapy exists for HDV. The HDV envelope requires HBV surface antigen proteins provided by HBV. Once inside a cell, however, HDV can replicate its genome in the absence of any HBV gene products. In vitro, HDV virion assembly is critically dependent on prenyl lipid modification, or prenylation, of its nucleocapsid-like protein large delta antigen. To overcome limitations of current animal models and to test the hypothesis that pharmacologic prenylation inhibition can prevent the production of HDV virions in vivo, we established a convenient mouse-based model of HDV infection capable of yielding viremia. Such mice were then treated with the prenylation inhibitors FTI-277 and FTI-2153. Both agents were highly effective at clearing HDV viremia. As expected, HDV inhibition exhibited duration-of-treatment dependence. These results provide the first preclinical data supporting the in vivo efficacy of prenylation inhibition as a novel antiviral therapy with potential application to HDV and a wide variety of other viruses.
Collapse
Affiliation(s)
- Bruno B Bordier
- Division of Gastroenterology and Hepatology, Stanford University School of Medicine, Palo Alto, California 94305, USA
| | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
|
40
|
Bordier BB, Marion PL, Ohashi K, Kay MA, Greenberg HB, Casey JL, Glenn JS. A prenylation inhibitor prevents production of infectious hepatitis delta virus particles. J Virol 2002; 76:10465-72. [PMID: 12239323 PMCID: PMC136538 DOI: 10.1128/jvi.76.20.10465-10472.2002] [Citation(s) in RCA: 107] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
Hepatitis delta virus (HDV) causes both acute and chronic liver disease throughout the world. Effective medical therapy is lacking. Previous work has shown that the assembly of HDV virus-like particles (VLPs) could be abolished by BZA-5B, a compound with farnesyltransferase inhibitory activity. Here we show that FTI-277, another farnesyltransferase inhibitor, prevented the production of complete, infectious HDV virions of two different genotypes. Thus, in spite of the added complexity and assembly determinants of infectious HDV virions compared to VLPs, the former are also sensitive to pharmacological prenylation inhibition. Moreover, production of HDV genotype III virions, which is associated with particularly severe clinical disease, was as sensitive to prenylation inhibition as was that of HDV genotype I virions. Farnesyltransferase inhibitors thus represent an attractive potential class of novel antiviral agents for use against HDV, including the genotypes associated with most severe disease.
Collapse
Affiliation(s)
- Bruno B Bordier
- Division of Gastroenterology and Hepatology, Stanford University School of Medicine, 269 Campus Drive, Palo Alto, CA 94305-5187, USA
| | | | | | | | | | | | | |
Collapse
|
|
41
|
Yamaguchi Y, Deléhouzée S, Handa H. HIV and hepatitis delta virus: evolution takes different paths to relieve blocks in transcriptional elongation. Microbes Infect 2002; 4:1169-75. [PMID: 12361917 DOI: 10.1016/s1286-4579(02)01641-6] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
The elongation step of transcription by RNA polymerase II (RNAPII) is controlled both positively and negatively by over a dozen cellular proteins. Recent findings suggest that two distinct viruses, human immunodeficiency virus type 1 and hepatitis delta virus, encode proteins that facilitate viral replication and transcription by targeting the same cellular transcription elongation machinery.
Collapse
Affiliation(s)
- Yuki Yamaguchi
- Graduate School of Bioscience and Biotechnology, 4259 Nagatsuta, Yokohama 226-8503, Japan
| | | | | |
Collapse
|
|
42
|
Sheu GT, Lai MM. Recombinant hepatitis delta antigen from E. coli promotes hepatitis delta virus RNA replication only from the genomic strand but not the antigenomic strand. Virology 2000; 278:578-86. [PMID: 11118380 DOI: 10.1006/viro.2000.0680] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Hepatitis delta antigen (HDAg) of hepatitis delta virus (HDV) typically consists of two related protein species. The small HDAg (S-HDAg) is a 24-kDa protein of 195 amino acids and the large HDAg (L-HDAg) is a 27-kDa protein with an additional 19 amino acids at its C-terminus. These two proteins have distinct functions in the HDV life cycle. We have developed conditions for expressing S-HDAg and L-HDAg in E. coli as soluble proteins to facilitate large-scale purification. These proteins were purified to homogeneity and shown to be biologically active. Transfection of the purified recombinant S-HDAg together with HDV genomic RNA resulted in viral RNA replication. Surprisingly, the purified S-HDAg could not initiate replication from the antigenomic-sense HDV RNA, even though the latter led to RNA replication when transfected with an mRNA encoding the S-HDAg. These results suggest that initiation of HDV RNA synthesis from the antigenomic RNA may require a form of HDAg that is modified in mammalian cells; in contrast, RNA synthesis from the genomic RNA could be initiated by the recombinant S-HDAg from E. coli. Interestingly, the purified L-HDAg appeared as multiple protein species, including one corresponding to S-HDAg, probably as a result of degradation. The partially proteolyzed L-HDAg also initiated HDV RNA replication under the same conditions. These results add to the mounting evidence that genomic- and antigenomic-strand HDV RNA syntheses are carried out by different mechanisms.
Collapse
Affiliation(s)
- G T Sheu
- Department of Molecular Microbiology and Immunology, Howard Hughes Medical Institute, Los Angeles, California 90033, USA
| | | |
Collapse
|
|
43
|
Hsu SC, Lin HP, Wu JC, Ko KL, Sheen IJ, Yan BS, Chou CK, Syu WJ. Characterization of a strain-specific monoclonal antibody to hepatitis delta virus antigen. J Virol Methods 2000; 87:53-62. [PMID: 10856752 DOI: 10.1016/s0166-0934(00)00147-6] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
Sequences of the hepatitis delta virus (HDV) vary to different degrees among isolates. A monoclonal antibody, designated as HP6A1, against the antigen of HDV (HDAg) has been characterized for its specificity. HP6A1 bound to HDAg of isolate 25 (genotype I) that was used for immunization, but not to others of both genotypes I and II. The epitope recognized by HP6A1 was then determined by a phage library displaying various heptapeptides. A consensus peptide deduced has the best match with that of residues 4-10 of HDAg (isolate 25). To confirm the phage mapping result, Escherichia coli recombinant proteins containing different lengths and various segments of HDAg (isolate 25) were constructed. The shortest HDAg segment contained in the fusion protein that reacted with HP6A1 was residues 1-10. When this peptide was added to the N-terminus of a heterologous protein engineered for eucaryotic expression, the fusion protein was detected by HP6A1. It is concluded that HP6A1 recognizes an epitope located at the N-terminus of HDAg (isolate 25). Since viruses of quasi-species exist in natural infections, a question of how different viral strains interact in vivo remains to be explored. The highly specific MAb opens a possibility to examine the fate of one strain in the presence of other related species in a cell transfection system.
Collapse
Affiliation(s)
- S C Hsu
- Institutes of Microbiology and Immunology, National Yang Ming University, Taipei, Taiwan
| | | | | | | | | | | | | | | |
Collapse
|
|
44
|
Abstract
Infection with hepatitis delta virus (HDV), a satellite virus of hepatitis B virus (HBV), is associated with severe and sometimes fulminant hepatitis. The traditional methods for the diagnosis of HDV infection, such as detection of serum anti-HD antibodies, are sufficient for the clinical diagnosis of delta infection. However, such techniques lack the sensitivity and specificity required to more accurately characterize the nature of HDV infection and to assess the efficacy of therapies. Recent improvements in molecular techniques, such as HDV RNA hybridization and RT-PCR, have provided increased diagnostic precision and a more thorough understanding of the natural course of HDV infection. These advances have enhanced the clinician's ability to accurately evaluate the stage of HDV infection, response to therapy, and occurrence of reinfection after orthotopic liver transplant. This review focuses on the recent advances in the understanding of the molecular biology of HDV and in the laboratory diagnosis of HDV infection.
Collapse
Affiliation(s)
- L E Modahl
- Department of Molecular Microbiology and Immunology, Howard Hughes Medical Institute, Los Angeles, CA, USA
| | | |
Collapse
|
|
45
|
Mu JJ, Wu HL, Chiang BL, Chang RP, Chen DS, Chen PJ. Characterization of the phosphorylated forms and the phosphorylated residues of hepatitis delta virus delta antigens. J Virol 1999; 73:10540-5. [PMID: 10559375 PMCID: PMC113112 DOI: 10.1128/jvi.73.12.10540-10545.1999] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Hepatitis delta virus (HDV) replication requires both the cellular RNA polymerase and one virus-encoded protein, small delta antigen (S-HDAg). S-HDAg has been shown to be a phosphoprotein, but its phosphorylation status is not yet clear. In this study, we employed three methods to address this question. A special two-dimensional gel electrophoresis, namely, nonequilibrium pH gradient electrophoresis, was used to separate the very basic S-HDAg. By carefully adjusting the pH of solubilization solution, the ampholyte composition, and the appropriate electrophoresis time periods, we were able to clearly resolve S-HDAg into two phosphorylated isoforms and one unphosphorylated form. In contrast, the viral large delta antigen (L-HDAg) can only be separated into one phosphorylated and one unphosphorylated form. By metabolic (32)P labeling, both immunoprecipitated S-HDAg and L-HDAg were found to incorporate radioactive phosphate. The extent of S-HDAg phosphorylation was increased upon 12-O-tetradecanoylphorbol-13-acetate treatment, while that of L-HDAg was not affected. Finally, phosphoamino acid analysis identified serine and threonine as the phospho residues in the labeled S-HDAg and only serine in the L-HDAg. Therefore, HDV S- and L-HDAgs differ in their phosphorylation patterns, which may account for their distinct biological functions.
Collapse
Affiliation(s)
- J J Mu
- Graduate Institute of Microbiology, College of Medicine, National Taiwan University, Taipei, Taiwan
| | | | | | | | | | | |
Collapse
|
|
46
|
Abstract
The purpose of this article is to give a concise update on our understanding of hepatitis delta virus (HDV). For more extensive background information the reader is directed to published reviews [1-5].
Collapse
Affiliation(s)
- J M Taylor
- Fox Chase Cancer Center, Philadelphia, Pa., USA
| |
Collapse
|
|
47
|
Moraleda G, Seeholzer S, Bichko V, Dunbrack R, Otto J, Taylor J. Unique properties of the large antigen of hepatitis delta virus. J Virol 1999; 73:7147-52. [PMID: 10438801 PMCID: PMC104238 DOI: 10.1128/jvi.73.9.7147-7152.1999] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
The large form of the hepatitis delta virus (HDV) protein (L) can be isoprenylated near its C terminus, and this modification is considered essential for particle assembly. Using gel electrophoresis, we separated L into two species of similar mobilities. The slower species could be labeled by the incorporation of [(14)C]mevalonolactone and is interpreted to be isoprenylated L (L(i)). In serum particles, infected liver, transfected cells, and assembled particles, 25 to 85% of L was isoprenylated. Isoprenylation was also demonstrated by (14)C incorporation in vitro with a rabbit reticulocyte coupled transcription-translation system. However, the species obtained migrated even slower than that detected by labeling in vivo. Next, in studies of HDV particle assembly in the presence of the surface proteins of human hepatitis B virus, we observed the following. (i) Relative to L, L(i) was preferentially assembled into virus-like particles. (ii) L(i) could coassemble the unmodified L and the small delta protein, S. (iii) In contrast, a form of L with a deletion in the dimerization domain was both isoprenylated and assembled, but it could not support the coassembly of S. Finally, to test the expectation that the isoprenylation of L would increase its hydrophobicity, we applied a phase separation strategy based on micelle formation with the nonionic detergent Triton X-114. We showed the following. (i) The unique C-terminal 19 amino acids present on L relative to S caused a significant increase in the hydrophobicity. (ii) This increase was independent of isoprenylation. (iii) In contrast, other, artificial modifications at either the N or C terminus of S did not increase the hydrophobicity. (iv) The increased hydrophobicity was not sufficient for particle assembly; nevertheless, we speculate that it might facilitate virion assembly.
Collapse
Affiliation(s)
- G Moraleda
- Fox Chase Cancer Center, Philadelphia, Pennsylvania 19111-2497, USA
| | | | | | | | | | | |
Collapse
|
|
48
|
Alejo A, Andrés G, Viñuela E, Salas ML. The African swine fever virus prenyltransferase is an integral membrane trans-geranylgeranyl-diphosphate synthase. J Biol Chem 1999; 274:18033-9. [PMID: 10364254 DOI: 10.1074/jbc.274.25.18033] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
In a previous study, it was shown that the protein encoded by the gene B318L of African swine fever virus (ASFV) is a trans-prenyltransferase that catalyzes in vitro the condensation of farnesyl diphosphate and isopentenyl diphosphate to synthesize geranylgeranyl diphosphate and longer chain prenyl diphosphates (Alejo, A., Yáñez, R. J., Rodríguez, J. M., Viñuela, E., and Salas, M. L. (1997) J. Biol. Chem. 272, 9417-9423). To investigate the in vivo function of the viral enzyme, we have determined, in this work, its subcellular localization and activity in cell extracts. Two systems were used in these studies: cells infected with ASFV and cells infected with a recombinant pseudo-Sindbis virus carrying the complete B318L gene. In this latter system, the trans-prenyltransferase was found to colocalize with the endoplasmic reticulum marker protein-disulfide isomerase, whereas in cells infected with ASFV, the viral enzyme was present in cytoplasmic viral assembly sites, associated with precursor viral membranes derived from the endoplasmic reticulum. In addition, after subcellular fractionation, the viral enzyme partitioned into the membrane fraction. Extraction of membrane proteins with alkaline carbonate and Triton X-114 indicated that the ASFV enzyme behaved as an integral membrane protein. The membrane enzyme synthesized predominantly all-trans-geranylgeranyl diphosphate from farnesyl diphosphate and isopentenyl diphosphate. These results indicate that the viral B318L protein is a trans-geranylgeranyl-diphosphate synthase, being the only enzyme of this type that is known to have a membrane localization.
Collapse
Affiliation(s)
- A Alejo
- Centro de Biología Molecular "Severo Ochoa" (Consejo Superior de Investigaciones Científicas-Universidad Autónoma de Madrid), Universidad Autónoma, Cantoblanco, 28049 Madrid, Spain
| | | | | | | |
Collapse
|
|
49
|
Taylor JM. Human hepatitis delta virus: an agent with similarities to certain satellite RNAs of plants. Curr Top Microbiol Immunol 1999; 239:107-22. [PMID: 9893371 DOI: 10.1007/978-3-662-09796-0_6] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Affiliation(s)
- J M Taylor
- Fox Chase Cancer Center, Philadelphia, PA 19111, USA
| |
Collapse
|
|
50
|
Jenna S, Sureau C. Effect of mutations in the small envelope protein of hepatitis B virus on assembly and secretion of hepatitis delta virus. Virology 1998; 251:176-86. [PMID: 9813213 DOI: 10.1006/viro.1998.9391] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
The gene coding for the small (S) envelope protein of hepatitis B virus was mutated to identify sequences important for the envelopment of the nucleocapsid during morphogenesis of hepatitis delta virus (HDV) virions. This study was focused on a domain of the S protein that is exposed in the cytoplasm during synthesis and thereby represented a good candidate for interaction with the viral nucleocapsid during virion assembly. The mutations consisted of deletion/insertions spanning the entire cytosolic domain of S between amino acid residues 24 and 80. Although the expression of mutants clustered between residues 59 and 80 could not be obtained, we demonstrated that a large part of the cytosolic loop, from residues 29-47 and 49-59, does not contain motifs essential for production of hepatitis B virus subviral particles or HDV virions. However, deletion of residues 24-28 led to the synthesis of S protein mutant, which was competent for secretion of subviral particles but deficient for production of HDV. We concluded that the sequence between Arg-24 and Ile-28 located at the carboxyl boundary of the transmembrane signal I for S contains residue or residues important for HDV particle assembly.
Collapse
Affiliation(s)
- S Jenna
- Laboratoire de Virologie, Institut de Biologie, 2 Boulevard Henri IV, Montpellier, 34060, France
| | | |
Collapse
|