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Shahini E, Argentiero A, Andriano A, Losito F, Maida M, Facciorusso A, Cozzolongo R, Villa E. Hepatitis E Virus: What More Do We Need to Know? MEDICINA (KAUNAS, LITHUANIA) 2024; 60:998. [PMID: 38929615 PMCID: PMC11205503 DOI: 10.3390/medicina60060998] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/10/2024] [Revised: 06/14/2024] [Accepted: 06/17/2024] [Indexed: 06/28/2024]
Abstract
Hepatitis E virus (HEV) infection is typically a self-limiting, acute illness that spreads through the gastrointestinal tract but replicates in the liver. However, chronic infections are possible in immunocompromised individuals. The HEV virion has two shapes: exosome-like membrane-associated quasi-enveloped virions (eHEV) found in circulating blood or in the supernatant of infected cell cultures and non-enveloped virions ("naked") found in infected hosts' feces and bile to mediate inter-host transmission. Although HEV is mainly spread via enteric routes, it is unclear how it penetrates the gut wall to reach the portal bloodstream. Both virion types are infectious, but they infect cells in different ways. To develop personalized treatment/prevention strategies and reduce HEV impact on public health, it is necessary to decipher the entry mechanism for both virion types using robust cell culture and animal models. The contemporary knowledge of the cell entry mechanism for these two HEV virions as possible therapeutic target candidates is summarized in this narrative review.
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Affiliation(s)
- Endrit Shahini
- Gastroenterology Unit, National Institute of Gastroenterology-IRCCS “Saverio de Bellis”, Castellana Grotte, 70013 Bari, Italy; (F.L.); (R.C.)
| | | | - Alessandro Andriano
- Department of Precision and Regenerative Medicine and Ionian Area, University of Bari Aldo Moro Medical School, 70124 Bari, Italy;
| | - Francesco Losito
- Gastroenterology Unit, National Institute of Gastroenterology-IRCCS “Saverio de Bellis”, Castellana Grotte, 70013 Bari, Italy; (F.L.); (R.C.)
| | - Marcello Maida
- Gastroenterology and Endoscopy Unit, S. Elia-Raimondi Hospital, 93100 Caltanissetta, Italy;
| | - Antonio Facciorusso
- Department of Medical and Surgical Sciences, University of Foggia, 71122 Foggia, Italy;
| | - Raffaele Cozzolongo
- Gastroenterology Unit, National Institute of Gastroenterology-IRCCS “Saverio de Bellis”, Castellana Grotte, 70013 Bari, Italy; (F.L.); (R.C.)
| | - Erica Villa
- Gastroenterology Unit, CHIMOMO Department, University of Modena & Reggio Emilia, Via del Pozzo 71, 41121 Modena, Italy
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Panajotov J, Falkenhagen A, Gadicherla AK, Johne R. Molecularly generated rat hepatitis E virus strains from human and rat show efficient replication in a human hepatoma cell line. Virus Res 2024; 344:199364. [PMID: 38522562 PMCID: PMC10995862 DOI: 10.1016/j.virusres.2024.199364] [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: 02/12/2024] [Revised: 03/18/2024] [Accepted: 03/18/2024] [Indexed: 03/26/2024]
Abstract
The hepatitis E virus (HEV) can cause acute and chronic hepatitis in humans. Whereas HEV genotypes 1-4 of species Paslahepevirus balayani are commonly found in humans, infections with ratHEV (species Rocahepevirus ratti) were previously considered to be restricted to rats. However, several cases of human ratHEV infections have been described recently. To investigate the zoonotic potential of this virus, a genomic clone was constructed here based on sequence data of ratHEV strain pt2, originally identified in a human patient with acute hepatitis from Hongkong. For comparison, genomic clones of ratHEV strain R63 from a rat and of HEV genotype 3 strain 47832mc from a human patient were used. After transfection of in vitro-transcribed RNA from the genomic clones into the human hepatoma cell line HuH-7-Lunet BLR, virus replication was shown for all strains by increasing genome copy numbers in cell culture supernatants. These cells developed persistent virus infections, and virus particles in the culture supernatant as well as viral antigen within the cells were demonstrated. All three generated virus strains successfully infected fresh HuH-7-Lunet BLR cells. In contrast, the human hepatoma cell lines HuH-7 and PLC/PRF/5 could only be infected with the genotype 3 strain and to a lesser extent with ratHEV strain R63. Infection of the rat-derived hepatoma cell lines clone 9, MH1C1 and H-4-II-E did not result in efficient virus replication for either strain. The results indicate that ratHEV strains from rats and humans can infect human hepatoma cells. The replication efficiency is strongly dependent on the cell line and virus strain. The investigated rat hepatoma cell lines could not be infected and other rat-derived cells should be tested in future to identify permissive cell lines from rats. The developed genomic clone can represent a useful tool for future research investigating pathogenicity and zoonotic potential of ratHEV.
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Affiliation(s)
| | | | - Ashish K Gadicherla
- German Federal Institute for Risk Assessment, 10589 Berlin, Germany; Center for Quantitative Cell Imaging, University of Wisconsin, Madison, USA
| | - Reimar Johne
- German Federal Institute for Risk Assessment, 10589 Berlin, Germany.
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3
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Li X, Sun X, Pinpin J, Zhao Q, Sun Y. Multifunctional ORF3 protein of hepatitis E virus. J Med Virol 2024; 96:e29691. [PMID: 38783788 DOI: 10.1002/jmv.29691] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2024] [Revised: 04/23/2024] [Accepted: 05/14/2024] [Indexed: 05/25/2024]
Abstract
Hepatitis E virus (HEV) is an emerging zoonotic pathogen that is transmitted primarily through the fecal-oral route and can cause acute hepatitis in humans. Since HEV was identified as a zoonotic pathogen, different species of HEV strains have been globally identified from various hosts, leading to an expanding range of hosts. The HEV genome consists of a 5' noncoding region, three open reading frames (ORFs), and a 3' noncoding region. The ORF3 protein is the smallest but has many functions in HEV release and pathogenesis. In this review, we systematically summarize recent progress in understanding the functions of the HEV ORF3 protein in virion release, biogenesis of quasi-enveloped viruses, antigenicity, and host environmental regulation. This review will help us to understand HEV replication and pathogenesis mechanisms better.
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Affiliation(s)
- Xiaoxuan Li
- Department of Preventive Veterinary Medicine, College of Veterinary Medicine, Northwest Agriculture and Forestry University, Yangling, Shaanxi, China
| | - Xuwen Sun
- Department of Preventive Veterinary Medicine, College of Veterinary Medicine, Northwest Agriculture and Forestry University, Yangling, Shaanxi, China
| | - Ji Pinpin
- Department of Preventive Veterinary Medicine, College of Veterinary Medicine, Northwest Agriculture and Forestry University, Yangling, Shaanxi, China
| | - Qin Zhao
- Department of Preventive Veterinary Medicine, College of Veterinary Medicine, Northwest Agriculture and Forestry University, Yangling, Shaanxi, China
| | - Yani Sun
- Department of Preventive Veterinary Medicine, College of Veterinary Medicine, Northwest Agriculture and Forestry University, Yangling, Shaanxi, China
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Primadharsini PP, Takahashi M, Nishizawa T, Sato Y, Nagashima S, Murata K, Okamoto H. The Full-Genome Analysis and Generation of an Infectious cDNA Clone of a Genotype 6 Hepatitis E Virus Variant Obtained from a Japanese Wild Boar: In Vitro Cultivation in Human Cell Lines. Viruses 2024; 16:842. [PMID: 38932135 PMCID: PMC11209168 DOI: 10.3390/v16060842] [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: 05/10/2024] [Revised: 05/22/2024] [Accepted: 05/22/2024] [Indexed: 06/28/2024] Open
Abstract
Hepatitis E virus (HEV) can cause self-limiting acute and chronic hepatitis infections, particularly in immunocompromised individuals. In developing countries, HEV is mainly transmitted via drinking contaminated water, whereas zoonotic transmission dominates the route of infection in developed countries, including Japan. Pigs are an important reservoir for HEV infection. Wild boars, which share the same genus and species as domestic pigs, are also an HEV reservoir. During our nationwide study of HEV infection in wild boar populations in Japan, a genotype 6 (HEV-6) strain, wbJHG_23, was isolated in Hyogo Prefecture in 2023. The genomic length was 7244 nucleotides, excluding the poly(A) tract. The wbJHG_23 strain exhibited the highest nucleotide identity throughout its genome with two previously reported HEV-6 strains (80.3-80.9%). Conversely, it displayed lower similarity (73.3-78.1%) with the HEV-1-5, HEV-7, and HEV-8 strains, indicating that, although closely related, the wbJHG_23 strain differs significantly from the reported HEV-6 strains and might represent a novel subtype. The wbJHG_23 strain successfully infected the human-derived cancer cell lines, PLC/PRF/5 and A549 1-1H8 cells, suggesting that HEV-6 has the potential for zoonotic infection. An infectious cDNA clone was constructed using a reverse genetics system, and a cell culture system supporting the efficient propagation of the HEV-6 strain was established, providing important tools for further studies on this genotype. Using this cell culture system, we evaluated the sensitivity of the wbJHG_23 strain to ribavirin treatment. Its good response to this treatment suggested that it could be used to treat human infections caused by HEV-6.
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Affiliation(s)
- Putu Prathiwi Primadharsini
- Division of Virology, Department of Infection and Immunity, Jichi Medical University School of Medicine, Shimotsuke, Tochigi 329-0498, Japan; (P.P.P.); (M.T.); (T.N.); (S.N.); (K.M.)
| | - Masaharu Takahashi
- Division of Virology, Department of Infection and Immunity, Jichi Medical University School of Medicine, Shimotsuke, Tochigi 329-0498, Japan; (P.P.P.); (M.T.); (T.N.); (S.N.); (K.M.)
| | - Tsutomu Nishizawa
- Division of Virology, Department of Infection and Immunity, Jichi Medical University School of Medicine, Shimotsuke, Tochigi 329-0498, Japan; (P.P.P.); (M.T.); (T.N.); (S.N.); (K.M.)
| | - Yukihiro Sato
- Department of Internal Medicine, Kamiichi General Hospital, Nakaniikawa-Gun, Toyama 930-0391, Japan;
| | - Shigeo Nagashima
- Division of Virology, Department of Infection and Immunity, Jichi Medical University School of Medicine, Shimotsuke, Tochigi 329-0498, Japan; (P.P.P.); (M.T.); (T.N.); (S.N.); (K.M.)
| | - Kazumoto Murata
- Division of Virology, Department of Infection and Immunity, Jichi Medical University School of Medicine, Shimotsuke, Tochigi 329-0498, Japan; (P.P.P.); (M.T.); (T.N.); (S.N.); (K.M.)
| | - Hiroaki Okamoto
- Division of Virology, Department of Infection and Immunity, Jichi Medical University School of Medicine, Shimotsuke, Tochigi 329-0498, Japan; (P.P.P.); (M.T.); (T.N.); (S.N.); (K.M.)
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5
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Lu Q, Wu H, Meng J, Wang J, Wu J, Liu S, Tong J, Nie J, Huang W. Multi-epitope vaccine design for hepatitis E virus based on protein ORF2 and ORF3. Front Microbiol 2024; 15:1372069. [PMID: 38577684 PMCID: PMC10991829 DOI: 10.3389/fmicb.2024.1372069] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2024] [Accepted: 03/07/2024] [Indexed: 04/06/2024] Open
Abstract
Introduction Hepatitis E virus (HEV), with heightened virulence in immunocompromised individuals and pregnant women, is a pervasive threat in developing countries. A globaly available vaccine against HEV is currently lacking. Methods We designed a multi-epitope vaccine based on protein ORF2 and ORF3 of HEV using immunoinformatics. Results The vaccine comprised 23 nontoxic, nonallergenic, soluble peptides. The stability of the docked peptide vaccine-TLR3 complex was validated by molecular dynamic simulations. The induction of effective cellular and humoral immune responses by the multi-peptide vaccine was verified by simulated immunization. Discussion These findings provide a foundation for future HEV vaccine studies.
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Affiliation(s)
- Qiong Lu
- Division of HIV/AIDS and Sex-transmitted Virus Vaccines, Institute for Biological Product Control, National Institutes for Food and Drug Control and WHO Collaborating Center for Standardization and Evaluation of Biologicals, Beijing, China
| | - Hao Wu
- Division of HIV/AIDS and Sex-transmitted Virus Vaccines, Institute for Biological Product Control, National Institutes for Food and Drug Control and WHO Collaborating Center for Standardization and Evaluation of Biologicals, Beijing, China
- Wuhan Institute of Biological Products Co., Ltd., Wuhan, China
| | - Jing Meng
- State Key Laboratory of Common Mechanism Research for Major Diseases, Suzhou Institute of Systems Medicine, Chinese Academy of Medical Sciences and Peking Union Medical College, Suzhou, Jiangsu, China
| | | | - Jiajing Wu
- Research and Development Department, Beijing Yunling Biotechnology Co., Ltd., Beijing, China
| | - Shuo Liu
- Changping Laboratory, Beijing, China
- Graduate School of Peking Union Medical College, Beijing, China
| | - Jincheng Tong
- Division of HIV/AIDS and Sex-transmitted Virus Vaccines, Institute for Biological Product Control, National Institutes for Food and Drug Control and WHO Collaborating Center for Standardization and Evaluation of Biologicals, Beijing, China
| | - Jianhui Nie
- Division of HIV/AIDS and Sex-transmitted Virus Vaccines, Institute for Biological Product Control, National Institutes for Food and Drug Control and WHO Collaborating Center for Standardization and Evaluation of Biologicals, Beijing, China
| | - Weijin Huang
- Division of HIV/AIDS and Sex-transmitted Virus Vaccines, Institute for Biological Product Control, National Institutes for Food and Drug Control and WHO Collaborating Center for Standardization and Evaluation of Biologicals, Beijing, China
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Chatterjee S, Kordbacheh R, Sin J. Extracellular Vesicles: A Novel Mode of Viral Propagation Exploited by Enveloped and Non-Enveloped Viruses. Microorganisms 2024; 12:274. [PMID: 38399678 PMCID: PMC10892846 DOI: 10.3390/microorganisms12020274] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2023] [Revised: 01/24/2024] [Accepted: 01/26/2024] [Indexed: 02/25/2024] Open
Abstract
Extracellular vesicles (EVs) are small membrane-enclosed structures that have gained much attention from researchers across varying scientific fields in the past few decades. Cells secrete diverse types of EVs into the extracellular milieu which include exosomes, microvesicles, and apoptotic bodies. These EVs play a crucial role in facilitating intracellular communication via the transport of proteins, lipids, DNA, rRNA, and miRNAs. It is well known that a number of viruses hijack several cellular pathways involved in EV biogenesis to aid in their replication, assembly, and egress. On the other hand, EVs can also trigger host antiviral immune responses by carrying immunomodulatory molecules and viral antigens on their surface. Owing to this intricate relationship between EVs and viruses, intriguing studies have identified various EV-mediated viral infections and interrogated how EVs can alter overall viral spread and longevity. This review provides a comprehensive overview on the EV-virus relationship, and details various modes of EV-mediated viral spread in the context of clinically relevant enveloped and non-enveloped viruses.
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Affiliation(s)
| | | | - Jon Sin
- Department of Biological Sciences, University of Alabama, 1325 Hackberry Lane, Tuscaloosa, AL 35401, USA; (S.C.); (R.K.)
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7
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Gremmel N, Keuling O, Eiden M, Groschup MH, Johne R, Becher P, Baechlein C. Hepatitis E virus neutralization by porcine serum antibodies. J Clin Microbiol 2023; 61:e0037323. [PMID: 37823649 PMCID: PMC10662371 DOI: 10.1128/jcm.00373-23] [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: 03/24/2023] [Accepted: 08/26/2023] [Indexed: 10/13/2023] Open
Abstract
The consumption of raw or undercooked meat products poses a serious risk for human hepatitis E virus (HEV) infections. In many high-income countries, domestic pigs and wild boars represent the main animal reservoirs for HEV and are usually identified by reverse transcription-PCR and antibody enzyme-linked immunosorbent assay (ELISA). In order to characterize the humoral immune response in more detail, a cell culture-based serum neutralization assay using a culture-adapted HEV strain was established here. Measurement of neutralizing antibodies was only possible after removing the viral quasi-envelope by detergent treatment. Serum samples of 343 wild boars from Northern Germany were first analyzed for anti-HEV IgG using an in-house ELISA, resulting in 19% positive samples. Subsequently, a subset of 41 representative samples was tested with the neutralization assay, and the results correlated well with those obtained by ELISA. Not only the human HEV strain 47832c but also two porcine HEV strains were shown to be neutralized by porcine serum antibodies. Neutralizing activity was also found in samples containing both HEV-specific antibodies and HEV RNA. Testing of serum samples derived from two experimentally infected domestic pigs showed a steep increase in neutralizing activity at 24 or 51 days post infection, dependent on the used infectious dose. The developed assay can be useful for characterization of the humoral immune response after HEV infection and for assessing the efficiency of HEV vaccine candidates.
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Affiliation(s)
- Nele Gremmel
- Department of Infectious Diseases, Institute of Virology, University of Veterinary Medicine, Hannover, Germany
| | - Oliver Keuling
- Institute for Terrestrial and Aquatic Wildlife Research, University of Veterinary Medicine, Hannover, Germany
| | - Martin Eiden
- Institute of Novel and Emerging Infectious Diseases, Friedrich-Loeffler-Institut, Federal Research Institute for Animal Health, Greifswald, Insel Riems, Germany
| | - Martin H. Groschup
- Institute of Novel and Emerging Infectious Diseases, Friedrich-Loeffler-Institut, Federal Research Institute for Animal Health, Greifswald, Insel Riems, Germany
| | - Reimar Johne
- Department of Biological Safety, German Federal Institute for Risk Assessment, Berlin, Germany
| | - Paul Becher
- Department of Infectious Diseases, Institute of Virology, University of Veterinary Medicine, Hannover, Germany
| | - Christine Baechlein
- Department of Infectious Diseases, Institute of Virology, University of Veterinary Medicine, Hannover, Germany
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Nagashima S, Primadharsini PP, Nishiyama T, Takahashi M, Murata K, Okamoto H. Development of a HiBiT-tagged reporter hepatitis E virus and its utility as an antiviral drug screening platform. J Virol 2023; 97:e0050823. [PMID: 37681960 PMCID: PMC10537679 DOI: 10.1128/jvi.00508-23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2023] [Accepted: 06/15/2023] [Indexed: 09/09/2023] Open
Abstract
Previously, we developed an infectious hepatitis E virus (HEV) harboring the nanoKAZ gene in the hypervariable region of the open reading frame 1 (ORF1) of the HEV3b (JE03-1760F/P10) genome and demonstrated the usefulness for screening anti-HEV drugs that inhibit the early infection process. In the present study, we constructed another reporter HEV (HEV3b-HiBiT) by placing a minimized HiBiT tag derived from NanoLuc luciferase at the 3'-end of the viral capsid (ORF2) coding sequence. It replicated efficiently in PLC/PRF/5 cells, produced membrane-associated particles identical to those of the parental virus, and was genetically stable and infectious. The HiBiT tag was fused to both secreted ORF2s (ORF2s-HiBiT) and ORF2c capsid protein (ORF2c-HiBiT). The ORF2c-HiBiT formed membrane-associated HEV particles (eHEV3b-HiBiT). By treating these particles with digitonin, we demonstrated that the HiBiT tag was expressed on the surface of capsid and was present inside the lipid membrane. To simplify the measurement of luciferase activity and provide a more convenient screening platform, we constructed an ORF2s-defective mutant (HEV3b-HiBiT/ΔORF2s) in which the secreted ORF2s are suppressed. We used this system to evaluate the effects of introducing small interfering RNAs and treatment with an inhibitor or accelerator of exosomal release on HEV egress and demonstrated that the effects on virus release can readily be analyzed. Therefore, HEV3b-HiBiT and HEV3b-HiBiT/ΔORF2s reporters may be useful for investigating the virus life cycle and can serve as a more convenient screening platform to search for candidate drugs targeting the late stage of HEV infection such as particle formation and release. IMPORTANCE The construction of recombinant infectious viruses harboring a stable luminescence reporter gene is essential for investigations of the viral life cycle, such as viral replication and pathogenesis, and the development of novel antiviral drugs. However, it is difficult to maintain the stability of a large foreign gene inserted into the viral genome. In the present study, we successfully generated a recombinant HEV harboring the 11-amino acid HiBiT tag in the ORF2 coding region and demonstrated the infectivity, efficient virus growth, particle morphology, and genetic stability, suggesting that this recombinant HEV is useful for in vitro assays. Furthermore, this system can serve as a more convenient screening platform for anti-HEV drugs. Thus, an infectious recombinant HEV is a powerful approach not only for elucidating the molecular mechanisms of the viral life cycle but also for the screening and development of novel antiviral agents.
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Affiliation(s)
- Shigeo Nagashima
- Division of Virology, Department of Infection and Immunity, Jichi Medical University School of Medicine, Tochigi, Japan
| | - Putu Prathiwi Primadharsini
- Division of Virology, Department of Infection and Immunity, Jichi Medical University School of Medicine, Tochigi, Japan
| | - Takashi Nishiyama
- Division of Virology, Department of Infection and Immunity, Jichi Medical University School of Medicine, Tochigi, Japan
| | - Masaharu Takahashi
- Division of Virology, Department of Infection and Immunity, Jichi Medical University School of Medicine, Tochigi, Japan
| | - Kazumoto Murata
- Division of Virology, Department of Infection and Immunity, Jichi Medical University School of Medicine, Tochigi, Japan
| | - Hiroaki Okamoto
- Division of Virology, Department of Infection and Immunity, Jichi Medical University School of Medicine, Tochigi, Japan
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Primadharsini PP, Nagashima S, Nishiyama T, Okamoto H. Three Distinct Reporter Systems of Hepatitis E Virus and Their Utility as Drug Screening Platforms. Viruses 2023; 15:1989. [PMID: 37896767 PMCID: PMC10611241 DOI: 10.3390/v15101989] [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: 09/09/2023] [Revised: 09/20/2023] [Accepted: 09/22/2023] [Indexed: 10/29/2023] Open
Abstract
The hepatitis E virus (HEV) is increasingly acknowledged as the primary cause of acute hepatitis. While most HEV infections are self-limiting, cases of chronic infection and fulminant hepatitis necessitate the administration of anti-HEV medications. However, there is a lack of specific antiviral drugs designed for HEV, and the currently available drug (ribavirin) has been associated with significant adverse effects. The development of innovative antiviral drugs involves targeting distinct steps within the viral life cycle: the early step (attachment and internalization), middle step (translation and RNA replication), and late step (virus particle formation and virion release). We recently established three HEV reporter systems, each covering one or two of these steps. Using these reporter systems, we identified various potential drug candidates that target different steps of the HEV life cycle. Through rigorous in vitro testing using our robust cell culture system with the genotype 3 HEV strain (JE03-1760F/P10), we confirmed the efficacy of these drugs, when used alone or in combination with existing anti-HEV drugs. This underscores their significance in the quest for an effective anti-HEV treatment. In the present review, we discuss the development of the three reporter systems, their applications in drug screening, and their potential to advance our understanding of the incompletely elucidated HEV life cycle.
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Affiliation(s)
- Putu Prathiwi Primadharsini
- Division of Virology, Department of Infection and Immunity, Jichi Medical University School of Medicine, 3311-1 Yakushiji, Shimotsuke 329-0498, Tochigi, Japan; (P.P.P.); (S.N.)
| | - Shigeo Nagashima
- Division of Virology, Department of Infection and Immunity, Jichi Medical University School of Medicine, 3311-1 Yakushiji, Shimotsuke 329-0498, Tochigi, Japan; (P.P.P.); (S.N.)
| | - Takashi Nishiyama
- Laboratory of Membrane Proteins, Research Division for Quantitative Life Sciences, Institute for Quantitative Biosciences, The University of Tokyo, 1-1-1 Yayoi, Bunkyo-ku, Tokyo 113-0032, Japan;
| | - Hiroaki Okamoto
- Division of Virology, Department of Infection and Immunity, Jichi Medical University School of Medicine, 3311-1 Yakushiji, Shimotsuke 329-0498, Tochigi, Japan; (P.P.P.); (S.N.)
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10
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Primadharsini PP, Nagashima S, Tanaka T, Jirintai S, Takahashi M, Murata K, Okamoto H. Development and Characterization of Efficient Cell Culture Systems for Genotype 1 Hepatitis E Virus and Its Infectious cDNA Clone. Viruses 2023; 15:v15040845. [PMID: 37112827 PMCID: PMC10146093 DOI: 10.3390/v15040845] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2023] [Revised: 03/21/2023] [Accepted: 03/25/2023] [Indexed: 03/29/2023] Open
Abstract
Hepatitis E virus (HEV) is a major cause of acute viral hepatitis globally. Genotype 1 HEV (HEV-1) is responsible for multiple outbreaks in developing countries, causing high mortality rates in pregnant women. However, studies on HEV-1 have been hindered by its poor replication in cultured cells. The JE04-1601S strain recovered from a Japanese patient with fulminant hepatitis E who contracted HEV-1 while traveling to India was serially passaged 12 times in human cell lines. The cell-culture-generated viruses (passage 12; p12) grew efficiently in human cell lines, but the replication was not fully supported in porcine cells. A full-length cDNA clone was constructed using JE04-1601S_p12 as a template. It was able to produce an infectious virus, and viral protein expression was detectable in the transfected PLC/PRF/5 cells and culture supernatants. Consistently, HEV-1 growth was also not fully supported in the cell culture of cDNA-derived JE04-1601S_p12 progenies, potentially recapitulating the narrow tropism of HEV-1 observed in vivo. The availability of an efficient cell culture system for HEV-1 and its infectious cDNA clone will be useful for studying HEV species tropism and mechanisms underlying severe hepatitis in HEV-1-infected pregnant women as well as for discovering and developing safer treatment options for this condition.
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Affiliation(s)
- Putu Prathiwi Primadharsini
- Division of Virology, Department of Infection and Immunity, Jichi Medical University School of Medicine, Shimotsuke, Tochigi 329-0414, Japan
| | - Shigeo Nagashima
- Division of Virology, Department of Infection and Immunity, Jichi Medical University School of Medicine, Shimotsuke, Tochigi 329-0414, Japan
| | - Toshinori Tanaka
- Division of Virology, Department of Infection and Immunity, Jichi Medical University School of Medicine, Shimotsuke, Tochigi 329-0414, Japan
| | - Suljid Jirintai
- Division of Virology, Department of Infection and Immunity, Jichi Medical University School of Medicine, Shimotsuke, Tochigi 329-0414, Japan
- Division of Pathology, Department of Basic Veterinary Medicine, Inner Mongolia Agricultural University College of Veterinary Medicine, Hohhot 010018, China
| | - Masaharu Takahashi
- Division of Virology, Department of Infection and Immunity, Jichi Medical University School of Medicine, Shimotsuke, Tochigi 329-0414, Japan
| | - Kazumoto Murata
- Division of Virology, Department of Infection and Immunity, Jichi Medical University School of Medicine, Shimotsuke, Tochigi 329-0414, Japan
| | - Hiroaki Okamoto
- Division of Virology, Department of Infection and Immunity, Jichi Medical University School of Medicine, Shimotsuke, Tochigi 329-0414, Japan
- Correspondence: ; Tel.: +81-285-58-7404
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11
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Cancela F, Rendon-Marin S, Quintero-Gil C, Houston DR, Gumbis G, Panzera Y, Pérez R, Arbiza J, Mirazo S. Modelling of Hepatitis E virus RNA-dependent RNA polymerase genotype 3 from a chronic patient and in silico interaction analysis by molecular docking with Ribavirin. J Biomol Struct Dyn 2023; 41:705-721. [PMID: 34861797 DOI: 10.1080/07391102.2021.2011416] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
Hepatitis E Virus (HEV) infection is an emergent zoonotic disease, where chronic hepatitis E associated to solid organ transplant (SOT) recipients, related to genotype 3, is the clinical manifestation of major concern. In this setting, ribavirin (RBV) treatment is the only available therapy, though drug-resistant variants could emerge leading to a therapeutic failure. Crystallographic structures have not been reported for most of the HEV proteins, including the RNA-polymerase (RdRp). Therefore, the mechanism of action of RBV against HEV and the molecular interactions between this drug and RdRp are largely unknown. In this work, we aimed to model in silico the 3 D structure of a novel HEV3 RdRp (HEV_C1_Uy) from a chronically HEV infected-SOT recipient treated with RBV and to perform a molecular docking simulation between RBV triphosphate (RBVT), 7-methyl-guanosine-5'-triphosphate and the modelled protein. The models were generated using I-TASSER server and validated with multiple bioinformatics tools. The docking analysis were carried out with AutoDock Vina and LeDock software. We obtained a suitable model for HEV_C1_Uy (C-Score=-1.33, RMSD = 10.4 ± 4.6 Å). RBVT displayed a binding affinity of -7.6 ± 0.2 Kcal/mol by molecular docking, mediated by 6 hydrogen-bonds (Q195-O14, S198-O11, E257-O13, S260-O2, O3, S311-O11) between the finger's-palm-domains and a free binding energy of 31.26 ± 16.81 kcal/mol by molecular dynamics simulations. We identified the possible HEV RdRp interacting region for incoming nucleotides or analogs and provide novel insights that will contribute to better understand the molecular interactions of RBV and the enzyme and the mechanism of action of this antiviral drug.Communicated by Ramaswamy H. Sarma.
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Affiliation(s)
- Florencia Cancela
- Sección Virología, Facultad de Ciencias, Universidad de la República, Montevideo, Uruguay
| | - Santiago Rendon-Marin
- Grupo de Investigación en Ciencias Animales - GRICA, Facultad de Medicina Veterinaria y Zootecnia, Universidad Cooperativa de Colombia, sede Bucaramanga, Bucaramanga, Colombia
| | - Carolina Quintero-Gil
- Grupo de Investigación en Ciencias Animales - GRICA, Facultad de Medicina Veterinaria y Zootecnia, Universidad Cooperativa de Colombia, sede Bucaramanga, Bucaramanga, Colombia
| | - Douglas R Houston
- Institute of Quantitative Biology, Biochemistry and Biotechnology, The University of Edinburgh, Edinburgh, UK
| | - Gediminas Gumbis
- Institute of Quantitative Biology, Biochemistry and Biotechnology, The University of Edinburgh, Edinburgh, UK
| | - Yanina Panzera
- Sección Genética Evolutiva, Instituto de Biología, Facultad de Ciencias, Universidad de la República, Montevideo, Uruguay
| | - Ruben Pérez
- Sección Genética Evolutiva, Instituto de Biología, Facultad de Ciencias, Universidad de la República, Montevideo, Uruguay
| | - Juan Arbiza
- Sección Virología, Facultad de Ciencias, Universidad de la República, Montevideo, Uruguay
| | - Santiago Mirazo
- Sección Virología, Facultad de Ciencias, Universidad de la República, Montevideo, Uruguay.,Departamento de Bacteriología y Virología, Instituto de Higiene, Facultad de Medicina, Universidad de la República, Montevideo, Uruguay
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12
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Dual Infection of Hepatitis A Virus and Hepatitis E Virus- What Is Known? Viruses 2023; 15:v15020298. [PMID: 36851512 PMCID: PMC9965669 DOI: 10.3390/v15020298] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2022] [Revised: 01/17/2023] [Accepted: 01/18/2023] [Indexed: 01/26/2023] Open
Abstract
Viral hepatitis is an infection of human hepatocytes resulting in liver damage. Dual infection of two hepatotropic viruses affects disease outcomes. The hepatitis A virus (HAV) and hepatitis E virus (HEV) are two enterically transmitted viruses; they are single-stranded RNA viruses and have common modes of transmission. They are transmitted mainly by the fecal-oral route and ingestion of contaminated food, though the HAV has no animal reservoirs. The HAV and HEV cause acute self-limiting disease; however, the HEV, but not HAV, can progress to chronic and extrahepatic infections. The HAV/HEV dual infection was reported among acute hepatitis patients present in developing countries. The impact of the HAV/HEV on the prognosis for acute hepatitis is not completely understood. Studies showed that the HAV/HEV dual infection increased abnormalities in the liver leading to fulminant hepatic failure (FHF) with a higher mortality rate compared to infection with a single virus. On the other hand, other reports showed that the clinical symptoms of the HAV/HEV dual infection were comparable to symptoms associated with the HAV or HEV monoinfection. This review highlights the modes of transmission, the prevalence of the HAV/HEV dual infection in various countries and among several study subjects, the possible outcomes of this dual infection, potential model systems for studying this dual infection, and methods of prevention of this dual infection and its associated complications.
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13
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Zhang J, Zheng Z, Xia N. Prophylactic Hepatitis E Vaccine. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2023; 1417:227-245. [PMID: 37223870 DOI: 10.1007/978-981-99-1304-6_16] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
The hepatitis E has been increasingly recognized as an underestimated global disease burden in recent years. Subpopulations with more serious infection associated damage or death include pregnant women, patients with basic liver diseases, and elderly persons. Vaccine would be the most effective means for prevention of HEV infection. The lack of an efficient cell culture system for HEV makes the development of classic inactive or attenuated vaccine infeasible. Hence, the recombinant vaccine approaches are explored deeply. The neutralizing sites are located almost exclusively in the capsid protein, pORF2, of the virion. Based on pORF2, many vaccine candidates showed potential of protecting primate animals, two of them were tested in human and evidenced to be well-tolerated in adults and highly efficacious in preventing hepatitis E. The world's first hepatitis E vaccine, Hecolin® (HEV 239 vaccine), was licensed in China and launched in 2012.
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Affiliation(s)
- Jun Zhang
- State Key Laboratory of Molecular Vaccinology and Molecular Diagnostics, National Institute of Diagnostics and Vaccine Development in Infectious Diseases, School of Public Health, Xiamen University, Xiamen, China.
| | - Zizheng Zheng
- State Key Laboratory of Molecular Vaccinology and Molecular Diagnostics, National Institute of Diagnostics and Vaccine Development in Infectious Diseases, School of Public Health, Xiamen University, Xiamen, China
| | - Ningshao Xia
- State Key Laboratory of Molecular Vaccinology and Molecular Diagnostics, National Institute of Diagnostics and Vaccine Development in Infectious Diseases, School of Public Health, Xiamen University, Xiamen, China
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14
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Ju X, Dong L, Ding Q. Hepatitis E Virus Life Cycle. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2023; 1417:141-157. [PMID: 37223864 DOI: 10.1007/978-981-99-1304-6_10] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
Hepatitis E virus (HEV) infects over 20 million people worldwide per year, leading to 30,000-40,000 deaths. In most cases HEV infection in a self-limited, acute illness. However, chronic infections could occur in immunocompromised individuals. Due to scarcity of robust cell culture models in vitro and genetic tractable animal models in vivo, the details of HEV life cycle, as well as its interaction with host cells still remain elusive, which dampens antivirals discovery. In this chapter, we present an update in the HEV infectious cycle steps: entry, genome replication/subgenomic RNA transcription, assembly, and release. Moreover, we discussed the future prospective on HEV research and illustrates important questions urgently to be addressed.
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Affiliation(s)
- Xiaohui Ju
- School of Medicine, Tsinghua University, Beijing, China
| | - Lin Dong
- School of Medicine, Tsinghua University, Beijing, China
| | - Qiang Ding
- School of Medicine, Tsinghua University, Beijing, China.
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15
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Zhang F, Wang Y. HEV Cell Culture. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2023; 1417:119-131. [PMID: 37223862 DOI: 10.1007/978-981-99-1304-6_8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
Cell culture is an important research method in virology. Although many attempts have been conducted to culture HEV in cells, only a few cell culture systems were considered to be efficient enough for usage. Concentration of virus stocks, host cells, and medium components affects the culture efficiency and the genetic mutations during HEV passage were found to be associated with the increased virulence in cell culture. As an alternative method for traditional cell culture, the infectious cDNA clones were constructed. The viral thermal stability, factors that impact the host range, post-translation of viral proteins, and function of different viral proteins were studied using the infectious cDNA clones. HEV cell culture studies on progeny virus showed that the viruses secreted from host cells have an envelope and its formation was associated with pORF3. This result explained the phenomenon that virus could infect host cells in the presence of anti-HEV antibodies.
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Affiliation(s)
- Feng Zhang
- Division of Therapeutical Monoclonal Antibodies, National Institutes for Food and Drug Control, Beijing, China
| | - Youchun Wang
- Institute of Medical Biology, Chinese Academy of Medical Science & Peking Union Medical College, Kunming, Yunnan Province, China.
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16
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Wang Y, Zhao C, Qi Y, Geng Y. Hepatitis E Virus. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2023; 1417:1-13. [PMID: 37223855 DOI: 10.1007/978-981-99-1304-6_1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
Since the sequence of hepatitis E virus (HEV) was determined from a patient with enterically transmitted non-A, non-B hepatitis in 1989, similar sequences have been isolated from many different animals, including pigs, wild boars, deer, rabbits, bats, rats, chicken, and trout. All of these sequences have the same genomic organization, which contains open reading frames (ORFs) 1, 2, and 3, although their genomic sequences are variable. Some have proposed that they be classified as new family, Hepeviridae, which would be further divided into different genera and species according to their sequence variability. The size of these virus particles generally ranged from 27 to 34 nm. However, HEV virions produced in cell culture differ in structure from the viruses found in feces. Those from cell culture have a lipid envelope and either lack or have a little ORF3, whereas the viruses isolated from feces lack a lipid envelope but have ORF3 on their surfaces. Surprisingly, most of the secreted ORF2 proteins from both these sources are not associated with HEV RNA.
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Affiliation(s)
- Youchun Wang
- Institute of Medical Biology, Chinese Academy of Medical Science & Peking Union Medical College, Kunming, China.
| | - Chenyan Zhao
- Division of HIV/AIDS and Sex-Transmitted Virus Vaccines, National Institutes for Food and Drug Control, Beijing, China
| | - Ying Qi
- Division of HIV/AIDS and Sex-Transmitted Virus Vaccines, National Institutes for Food and Drug Control, Beijing, China
| | - Yansheng Geng
- Key Laboratory of Public Health Safety of Hebei Province, School of Public Health, Hebei University, Baoding, China
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Zhou Y, Zhao C, Tian Y, Xu N, Wang Y. Characteristics and Functions of HEV Proteins. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2023; 1417:15-32. [PMID: 37223856 DOI: 10.1007/978-981-99-1304-6_2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
Hepatitis E virus (HEV) is a non-enveloped virus containing a single-stranded, positive-sense RNA genome of 7.2 kb, which consists of a 5' non-coding region, three open reading frames (ORFs), and a 3' non-coding region. ORF1 is diverse between genotypes and encodes the nonstructural proteins, which include the enzymes needed for virus replication. In addition to its role in virus replication, the function of ORF1 is relevant to viral adaption in culture and may also relate to virus infection and HEV pathogenicity. ORF2 protein is the capsid protein, which is about 660 amino acids in length. It not only protects the integrity of the viral genome, but is also involved in many important physiological activities, such as virus assembly, infection, host interaction, and innate immune response. The main immune epitopes, especially neutralizing epitopes, are located on ORF2 protein, which is a candidate antigen for vaccine development. ORF3 protein is a phosphoprotein of 113 or 114 amino acids with a molecular weight of 13 kDa with multiple functions that can also induce strong immune reactivity. A novel ORF4 has been identified only in genotype 1 HEV and its translation promotes viral replication.
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Affiliation(s)
- Yan Zhou
- RegCMC, Great Regulatory Affairs, Sanofi (China) Investment Co., Ltd, Beijing, China
| | - Chenyan Zhao
- Division of HIV/AIDS and Sex-Transmitted Virus Vaccines, National Institutes for Food and Drug Control, Beijing, China
| | - Yabin Tian
- Division II of In Vitro Diagnostics for Infectious Diseases, National Institutes for Food and Drug Control, Beijing, China
| | - Nan Xu
- Division of HIV/AIDS and Sex-Transmitted Virus Vaccines, National Institutes for Food and Drug Control, Beijing, China
| | - Youchun Wang
- Institute of Medical Biology, Chinese Academy of Medical Science & Peking Union Medical College, Kunming, China.
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Sayed IM, Abdelwahab SF. Is Hepatitis E Virus a Neglected or Emerging Pathogen in Egypt? Pathogens 2022; 11:1337. [PMID: 36422589 PMCID: PMC9697431 DOI: 10.3390/pathogens11111337] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2022] [Revised: 11/04/2022] [Accepted: 11/08/2022] [Indexed: 09/02/2023] Open
Abstract
Though Egypt ranks among the top countries for viral hepatitis and death-related liver disease, Hepatitis E virus (HEV) is a neglected pathogen. Living in villages and rural communities with low sanitation, use of underground well water and contact with animals are the main risk factors for HEV infection. Domestic animals, especially ruminants and their edible products, are one source of infection. Contamination of water by either human or animal stools is the main route of infection. In addition, HEV either alone or in coinfection with other hepatotropic viruses has been recorded in Egyptian blood donors. HEV seropositivity among Egyptian villagers was 60-80%, especially in the first decade of life. Though HEV seropositivity is the highest among Egyptians, HEV infection is not routinely diagnosed in Egyptian hospitals. The initial manifestations of HEV among Egyptians is a subclinical infection, although progression to fulminant hepatic failure has been recorded. With the improvement in serological and molecular approaches and increasing research on HEV, it is becoming clear that HEV represents a threat for Egyptians and preventive measures should be considered to reduce the infection rate and possible complications.
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Affiliation(s)
- Ibrahim M. Sayed
- Department of Biomedical and Nutritional Sciences, University of Massachusetts Lowell, Lowell, MA 01854, USA
- Department of Medical Microbiology and Immunology, Faculty of Medicine, Assiut University, Assiut 71515, Egypt
| | - Sayed F. Abdelwahab
- Department of Pharmaceutics and Industrial Pharmacy, College of Pharmacy, Taif University, P.O. Box 11099, Taif 21944, Saudi Arabia
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Primadharsini PP, Nagashima S, Takahashi M, Murata K, Okamoto H. Ritonavir Blocks Hepatitis E Virus Internalization and Clears Hepatitis E Virus In Vitro with Ribavirin. Viruses 2022; 14:v14112440. [PMID: 36366538 PMCID: PMC9697947 DOI: 10.3390/v14112440] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2022] [Revised: 10/29/2022] [Accepted: 10/31/2022] [Indexed: 11/06/2022] Open
Abstract
Hepatitis E virus (HEV) is increasingly recognized as the leading cause of acute hepatitis. Although HEV infections are mostly self-limiting, a chronic course can develop especially in those with immunocompromised state. Ribavirin is currently used to treat such patients. According to various reports on chronic HEV infections, a sustained virological response (SVR) was achieved in approximately 80% of patients receiving ribavirin monotherapy. To increase the SVR rate, drug combination might be a viable strategy, which we attempted in the current study. Ritonavir was identified in our previous drug screening while searching for candidate novel anti-HEV drugs. It demonstrated potent inhibition of HEV growth in cultured cells. In the present study, ritonavir blocked HEV internalization as shown through time-of-addition and immunofluorescence assays. Its combination with ribavirin significantly increased the efficiency of inhibiting HEV growth compared to that shown by ribavirin monotherapy, even in PLC/PRF/5 cells with robust HEV production, and resulted in viral clearance. Similar efficiency was seen for HEV genotypes 3 and 4, the main causes of chronic infection. The present findings provide insight concerning the advantage of combination therapy using drugs blocking different steps in the HEV life cycle (internalization and RNA replication) as a potential novel treatment strategy for chronic hepatitis E.
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Muñoz-Chimeno M, Rodriguez-Paredes V, García-Lugo MA, Avellon A. Hepatitis E genotype 3 genome: A comprehensive analysis of entropy, motif conservation, relevant mutations, and clade-associated polymorphisms. Front Microbiol 2022; 13:1011662. [PMID: 36274715 PMCID: PMC9582770 DOI: 10.3389/fmicb.2022.1011662] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2022] [Accepted: 09/20/2022] [Indexed: 11/13/2022] Open
Abstract
Hepatitis E virus genotype 3 (HEV-3) is an EU/EEA emergent zoonosis. HEV-3 clades/subtypes have been described. Its genome contains ORF1, which encodes nonstructural proteins for virus replication, ORF2, the capsid protein, and ORF3, a multifunctional protein involved in virion pathogenesis. The study aims with respect to HEV-3 are to: (1) calculate genome entropy (excluding hypervariable region); (2) analyze the described motifs/mutations; (3) characterize clade/subtype genome polymorphisms. Seven hundred and five sequences from the GenBank database were used. The highest entropies were identified in zoonotic genotypes (HEV-3 and HEV-4) with respect to HEV-1 in X domain, RdRp, ORF2, and ORF3. There were statistically significant differences in the entropy between proteins, protease and ORF3 being the most variable and Y domain being the most conserved. Methyltransferase and Y domain motifs were completely conserved. By contrast, essential protease H581 residue and catalytic dyad exhibited amino acid changes in 1.8% and 0.4% of sequences, respectively. Several X domain amino acids were associated with clades. We found sequences with mutations in all helicase motifs except number IV. Helicase mutations related to increased virulence and/or fulminant hepatitis were frequent, the 1,110 residue being a typical HEV-3e and HEV-3f-A2 polymorphism. RdRp motifs III, V, VII also had high mutation rates. Motif III included residues that are polymorphisms of HEV-3e (F1449) and HEV-3 m (D1451). RdRp ribavirin resistance mutations were frequent, mainly 1479I (67.4, 100% in HEV-3efglmk) and 1634R/K (10.0%, almost 100% in HEV-3e). With respect to ORF2, 19/27 neutralization epitopes had mutations. The S80 residue in ORF3 presented mutations in 3.5% of cases. Amino acids in the ORF3-PSAP motif had high substitution rates, being more frequent in the first PSAP (44.8%) than in the second (1.5%). This is the first comprehensive analysis of the HEV-3 genome, aimed at improving our knowledge of the genome, and establishing the basis for future genotype-to-phenotype analysis, given that viral features associated with severity have not been explored in depth. Our results demonstrate there are important genetic differences in the studied genomes that sometimes affect significant viral structures, and constitute clade/subtype polymorphisms that may affect the clinical course or treatment efficacy.
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Affiliation(s)
- Milagros Muñoz-Chimeno
- Hepatitis Unit, National Center of Microbiology, Carlos III Institute of Health, Madrid, Spain
- Alcalá de Henares University, Madrid, Spain
| | | | | | - Ana Avellon
- Hepatitis Unit, National Center of Microbiology, Carlos III Institute of Health, Madrid, Spain
- CIBERESP Epidemiology and Public Health, Madrid, Spain
- *Correspondence: Ana Avellon,
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21
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Kinast V, Klöhn M, Nocke MK, Todt D, Steinmann E. Hepatitis E virus species barriers: seeking viral and host determinants. Curr Opin Virol 2022; 56:101274. [PMID: 36283248 DOI: 10.1016/j.coviro.2022.101274] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2022] [Revised: 09/19/2022] [Accepted: 09/21/2022] [Indexed: 11/03/2022]
Abstract
The intimate relationship between virus and host cell can result in highly adapted viruses that are restricted to a single host. However, some viruses have the ability to infect multiple host species. Remarkably, hepatitis E viruses (HEV) comprise genotypes that are either 'single-host' or 'multi-host' genotypes, a trait that raises fundamental questions: Why do different genotypes differ in their host range, despite a high degree of genomic similarity? What are the underlying molecular determinants that shape species barriers? Here, we review the current knowledge of viral and host determinants that may affect the evolutionary trajectories of HEV. We also provide a perspective on techniques and methods that address open questions of HEV host range and adaptation.
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Affiliation(s)
- Volker Kinast
- Department of Molecular and Medical Virology, Ruhr University Bochum, Bochum, Germany; Department of Medical Microbiology and Virology, Carl von Ossietzky University Oldenburg, Oldenburg, Germany
| | - Mara Klöhn
- Department of Molecular and Medical Virology, Ruhr University Bochum, Bochum, Germany
| | - Maximilian K Nocke
- Department of Molecular and Medical Virology, Ruhr University Bochum, Bochum, Germany
| | - Daniel Todt
- Department of Molecular and Medical Virology, Ruhr University Bochum, Bochum, Germany; European Virus Bioinformatics Center (EVBC), 07743 Jena, Germany.
| | - Eike Steinmann
- Department of Molecular and Medical Virology, Ruhr University Bochum, Bochum, Germany; German Centre for Infection Research (DZIF), External Partner Site, Bochum, Germany.
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Go HJ, Park BJ, Ahn HS, Han SH, Kim DH, Lyoo EL, Kim DY, Kim JH, Lee JB, Park SY, Song CS, Lee SW, Choi YK, Choi IS. Immunization with Virus-Like Particle Vaccine Protects Rabbits against Hepatitis E-3 Virus Infection. Viruses 2022; 14:v14071432. [PMID: 35891413 PMCID: PMC9322348 DOI: 10.3390/v14071432] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2022] [Revised: 06/25/2022] [Accepted: 06/27/2022] [Indexed: 02/04/2023] Open
Abstract
Here, rabbits were immunized with a virus-like particle (VLP) vaccine prepared by expressing 239 amino acids of the swine hepatitis E virus (HEV)-3 capsid protein using a baculovirus system. Thirty specific-pathogen-free rabbits were divided into five groups (negative and positive control and 10, 50, and 100 μg VLP-vaccinated). Positive control group rabbits showed viremia and fecal viral shedding, whereas rabbits vaccinated with 10 μg VLP showed transient fecal viral shedding, and rabbits vaccinated with 50 and 100 μg VLP did not show viremia or fecal viral shedding. Serum anti-HEV antibody titers increased in a dose-dependent manner. Anti-HEV antibody titers were significantly higher (p < 0.05) in 100 μg VLP-vaccinated rabbits than in the negative control rabbits at week 4. Anti-HEV antibody titers were significantly higher in 50 and 10 μg VLP-vaccinated rabbits than in the negative control rabbits at weeks 8 and 11, respectively. Serum IFN-γ and IL-12 levels were significantly higher (p < 0.01) in rabbits vaccinated with 50 and 100 μg VLP than in the negative control rabbits at weeks 4 and 6. Liver tissues of 50 and 100 μg VLP-vaccinated rabbits displayed significantly less (p < 0.05) fibrosis than those of the positive control rabbits. The prepared VLP vaccine demonstrated dose-dependent immunogenicity sufficient for inducing anti-HEV antibody production, thus protecting rabbits against swine HEV-3.
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Affiliation(s)
- Hyeon-Jeong Go
- Department of Infectious Disease, College of Veterinary Medicine, Konkuk University, 120 Neundong-ro, Gwangjin-gu, Seoul 05029, Korea; (H.-J.G.); (B.-J.P.); (H.-S.A.); (S.-H.H.); (D.-H.K.); (E.-L.L.); (D.-Y.K.); (J.-H.K.); (J.-B.L.); (S.-Y.P.); (C.-S.S.); (S.-W.L.)
| | - Byung-Joo Park
- Department of Infectious Disease, College of Veterinary Medicine, Konkuk University, 120 Neundong-ro, Gwangjin-gu, Seoul 05029, Korea; (H.-J.G.); (B.-J.P.); (H.-S.A.); (S.-H.H.); (D.-H.K.); (E.-L.L.); (D.-Y.K.); (J.-H.K.); (J.-B.L.); (S.-Y.P.); (C.-S.S.); (S.-W.L.)
| | - Hee-Seop Ahn
- Department of Infectious Disease, College of Veterinary Medicine, Konkuk University, 120 Neundong-ro, Gwangjin-gu, Seoul 05029, Korea; (H.-J.G.); (B.-J.P.); (H.-S.A.); (S.-H.H.); (D.-H.K.); (E.-L.L.); (D.-Y.K.); (J.-H.K.); (J.-B.L.); (S.-Y.P.); (C.-S.S.); (S.-W.L.)
| | - Sang-Hoon Han
- Department of Infectious Disease, College of Veterinary Medicine, Konkuk University, 120 Neundong-ro, Gwangjin-gu, Seoul 05029, Korea; (H.-J.G.); (B.-J.P.); (H.-S.A.); (S.-H.H.); (D.-H.K.); (E.-L.L.); (D.-Y.K.); (J.-H.K.); (J.-B.L.); (S.-Y.P.); (C.-S.S.); (S.-W.L.)
| | - Dong-Hwi Kim
- Department of Infectious Disease, College of Veterinary Medicine, Konkuk University, 120 Neundong-ro, Gwangjin-gu, Seoul 05029, Korea; (H.-J.G.); (B.-J.P.); (H.-S.A.); (S.-H.H.); (D.-H.K.); (E.-L.L.); (D.-Y.K.); (J.-H.K.); (J.-B.L.); (S.-Y.P.); (C.-S.S.); (S.-W.L.)
| | - Eu-Lim Lyoo
- Department of Infectious Disease, College of Veterinary Medicine, Konkuk University, 120 Neundong-ro, Gwangjin-gu, Seoul 05029, Korea; (H.-J.G.); (B.-J.P.); (H.-S.A.); (S.-H.H.); (D.-H.K.); (E.-L.L.); (D.-Y.K.); (J.-H.K.); (J.-B.L.); (S.-Y.P.); (C.-S.S.); (S.-W.L.)
| | - Da-Yoon Kim
- Department of Infectious Disease, College of Veterinary Medicine, Konkuk University, 120 Neundong-ro, Gwangjin-gu, Seoul 05029, Korea; (H.-J.G.); (B.-J.P.); (H.-S.A.); (S.-H.H.); (D.-H.K.); (E.-L.L.); (D.-Y.K.); (J.-H.K.); (J.-B.L.); (S.-Y.P.); (C.-S.S.); (S.-W.L.)
| | - Jae-Hyeong Kim
- Department of Infectious Disease, College of Veterinary Medicine, Konkuk University, 120 Neundong-ro, Gwangjin-gu, Seoul 05029, Korea; (H.-J.G.); (B.-J.P.); (H.-S.A.); (S.-H.H.); (D.-H.K.); (E.-L.L.); (D.-Y.K.); (J.-H.K.); (J.-B.L.); (S.-Y.P.); (C.-S.S.); (S.-W.L.)
| | - Joong-Bok Lee
- Department of Infectious Disease, College of Veterinary Medicine, Konkuk University, 120 Neundong-ro, Gwangjin-gu, Seoul 05029, Korea; (H.-J.G.); (B.-J.P.); (H.-S.A.); (S.-H.H.); (D.-H.K.); (E.-L.L.); (D.-Y.K.); (J.-H.K.); (J.-B.L.); (S.-Y.P.); (C.-S.S.); (S.-W.L.)
- KU Center for Animal Blood Medical Science, Konkuk University, 120 Neungdong-ro, Gwangjin-gu, Seoul 05029, Korea
- Konkuk University Zoonotic Diseases Research Center, Konkuk University, 120 Neungdong-ro, Gwangjin-gu, Seoul 05029, Korea
| | - Seung-Yong Park
- Department of Infectious Disease, College of Veterinary Medicine, Konkuk University, 120 Neundong-ro, Gwangjin-gu, Seoul 05029, Korea; (H.-J.G.); (B.-J.P.); (H.-S.A.); (S.-H.H.); (D.-H.K.); (E.-L.L.); (D.-Y.K.); (J.-H.K.); (J.-B.L.); (S.-Y.P.); (C.-S.S.); (S.-W.L.)
- KU Center for Animal Blood Medical Science, Konkuk University, 120 Neungdong-ro, Gwangjin-gu, Seoul 05029, Korea
- Konkuk University Zoonotic Diseases Research Center, Konkuk University, 120 Neungdong-ro, Gwangjin-gu, Seoul 05029, Korea
| | - Chang-Seon Song
- Department of Infectious Disease, College of Veterinary Medicine, Konkuk University, 120 Neundong-ro, Gwangjin-gu, Seoul 05029, Korea; (H.-J.G.); (B.-J.P.); (H.-S.A.); (S.-H.H.); (D.-H.K.); (E.-L.L.); (D.-Y.K.); (J.-H.K.); (J.-B.L.); (S.-Y.P.); (C.-S.S.); (S.-W.L.)
- KU Center for Animal Blood Medical Science, Konkuk University, 120 Neungdong-ro, Gwangjin-gu, Seoul 05029, Korea
- Konkuk University Zoonotic Diseases Research Center, Konkuk University, 120 Neungdong-ro, Gwangjin-gu, Seoul 05029, Korea
| | - Sang-Won Lee
- Department of Infectious Disease, College of Veterinary Medicine, Konkuk University, 120 Neundong-ro, Gwangjin-gu, Seoul 05029, Korea; (H.-J.G.); (B.-J.P.); (H.-S.A.); (S.-H.H.); (D.-H.K.); (E.-L.L.); (D.-Y.K.); (J.-H.K.); (J.-B.L.); (S.-Y.P.); (C.-S.S.); (S.-W.L.)
- KU Center for Animal Blood Medical Science, Konkuk University, 120 Neungdong-ro, Gwangjin-gu, Seoul 05029, Korea
- Konkuk University Zoonotic Diseases Research Center, Konkuk University, 120 Neungdong-ro, Gwangjin-gu, Seoul 05029, Korea
| | - Yang-Kyu Choi
- Department of Laboratory Animal Medicine, College of Veterinary Medicine, Konkuk University, 120 Neundong-ro, Gwangjin-gu, Seoul 05029, Korea;
| | - In-Soo Choi
- Department of Infectious Disease, College of Veterinary Medicine, Konkuk University, 120 Neundong-ro, Gwangjin-gu, Seoul 05029, Korea; (H.-J.G.); (B.-J.P.); (H.-S.A.); (S.-H.H.); (D.-H.K.); (E.-L.L.); (D.-Y.K.); (J.-H.K.); (J.-B.L.); (S.-Y.P.); (C.-S.S.); (S.-W.L.)
- KU Center for Animal Blood Medical Science, Konkuk University, 120 Neungdong-ro, Gwangjin-gu, Seoul 05029, Korea
- Konkuk University Zoonotic Diseases Research Center, Konkuk University, 120 Neungdong-ro, Gwangjin-gu, Seoul 05029, Korea
- Correspondence: ; Tel.: +82-2-2049-6055
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Abstract
Hepatitis E virus (HEV) is a major cause of acute viral hepatitis in humans. A convenient small mammalian model for basic research and antiviral testing is still greatly needed. Although a small rodent, the Mongolian gerbil, was reported to be susceptible to swine genotype-4 HEV infection, whether the previous results were reliable and consistent needs to be validated by using biologically pure HEV stocks or infectious RNA. In this study, we revisited this gerbil infection model for human HEV of genotype 1, 3, or 4 (G1, G3, or G4) by HEV reverse genetics. Gerbils inoculated intrahepatically with capped G3 HEV RNA transcripts or intraperitoneally with infectious G3 cloned HEV produced robust infection, as evidenced by presence of HEV in livers, spleens, and feces for up to 7 weeks post inoculation, seroconversion, and pathological liver lesions. Furthermore, the value of the gerbil model in antiviral testing and type I IFN in host defense was assessed. We demonstrated the effectiveness of peg-IFNα-2a and ribavirin in inhibiting HEV replication in gerbils. By treatment with two molecule inhibitors of TBK1, we also revealed a role of RIG-I like receptor-interferon regulatory factor 3 in host anti-HEV innate immune sensing in this in vivo model. Finally, susceptibility of G4 HEV was demonstrated in intrahepatically inoculated gerbils with infectious HEV RNA transcripts, whereas no evidence for G1 HEV susceptibility was found. The availability of the convenient gerbil model will greatly facilitate HEV-specific antiviral development and assess the mechanism of host immune response during HEV infection. IMPORTANCE HEV infects >20 million people annually, causing acute viral hepatitis as well as chronic hepatitis, neurological diseases, and pregnancy-associated high mortality, which require therapeutic intervention. The HEV antiviral research is largely limited by the lack of a convenient small animal model. Here we revisit the Mongolian gerbil model for three genotypes of human HEV by infectious HEV clones and recognized standards of experimental procedures. Fecal virus shedding, seroconversion, and pathological liver lesions could be detected in HEV-inoculated gerbils. We demonstrate the effectiveness and usefulness of this model in testing antiviral drugs, and in assessing the mechanism of host innate immune response upon HEV infection. This conventional rodent model will aid in future antiviral development and delineating mechanism of host immune response.
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El-Kafrawy SA, El-Daly MM. Hepatitis E virus in Saudi Arabia: more surveillance needed. Future Virol 2022. [DOI: 10.2217/fvl-2021-0320] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Hepatitis E virus (HEV) is a small quasi-enveloped ssRNA causing acute hepatitis. HEV is the leading cause of intermittent acute hepatitis and fulminant hepatic failure. Risk factors include drinking contaminated water in developing countries and consumption of infected animal products in developed countries. Previous reports on HEV prevalence in Saudi Arabia had small sample sizes. Nationwide systematic seroprevalence studies are needed to investigate risk factors and annual incidence. Camels play a cultural and economic role in the life of Saudi citizens with frequent human contact and potential role in zoonotic transmission. Future research needs to include larger sample-sizes and nationwide studies. Future studies should also focus on raising awareness of HEV infection and the need for wider population testing and screening.
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Affiliation(s)
- Sherif Aly El-Kafrawy
- Special Infectious Agents Unit-BSL3, King Fahd Medical Research Center, King Abdulaziz University, Jeddah, 21589, Saudi Arabia
- Department of Medical Laboratory Sciences, Faculty of Applied Medical Sciences, King Abdulaziz University, Jeddah, 21589, Saudi Arabia
| | - Mai Mohamed El-Daly
- Special Infectious Agents Unit-BSL3, King Fahd Medical Research Center, King Abdulaziz University, Jeddah, 21589, Saudi Arabia
- Department of Medical Laboratory Sciences, Faculty of Applied Medical Sciences, King Abdulaziz University, Jeddah, 21589, Saudi Arabia
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25
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Development of recombinant infectious hepatitis E virus harboring the nanoKAZ gene and its application in drug screening. J Virol 2022; 96:e0190621. [PMID: 35107380 DOI: 10.1128/jvi.01906-21] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Hepatitis E virus (HEV) is a quasi-enveloped virus with a single-stranded positive-sense RNA genome belonging to family Hepeviridae. Studies on molecular aspects of HEV and drug screening have benefited from the discovery of bioluminescent reporter genes. However, the stability of large foreign genes is difficult to maintain after insertion into the viral genome. Currently, ribavirin is used to treat HEV-infected patients who require antiviral therapy. This has several major drawbacks. Thus, the development of novel anti-HEV drugs is of great importance. We developed a system consisting of recombinant infectious HEV harboring small luciferase gene (nanoKAZ) in the hypervariable region (HVR) of the open reading frame 1 (ORF1) (HEV-nanoKAZ). It replicated efficiently in cultured cells, was genetically stable, and had morphological characteristics similar to the parental virus. Both membrane-associated (eHEV-nanoKAZ) and membrane-unassociated (neHEV-nanoKAZ) particles were infectious. HEV particles circulating in the blood stream and attaching to hepatocytes in HEV-infected patients are membrane-associated, thus, eHEV-nanoKAZ was applied in drug screening. The eHEV-nanoKAZ system is able to cover at least the inhibitor of HEV entry and inhibitor of HEV RNA replication. Four drugs with anti-HEV activity were identified. Their effectiveness in cultured cells was confirmed in naïve and HEV-producing PLC/PRF/5 cells. Two hit drugs (azithromycin and ritonavir) strongly inhibited HEV production in culture supernatants, as well as intracellular expression of ORF2 protein, and may therefore be candidate novel anti-HEV drugs. The HEV-nanoKAZ system was developed and applied in drug screening, and is expected to be useful for investigating the HEV life cycle. IMPORTANCE Bioluminescent reporter viruses are essential tools in molecular virological research. It has been widely used to investigate viral life cycles and in the development of antiviral drugs. For drug screening, the use of a bioluminescent reporter virus helps shorten the time required to perform the assay. A system, consisting of recombinant infectious HEV harboring the nanoKAZ gene in the HVR of ORF1 (HEV-nanoKAZ), was developed in this study, and was successfully applied to drug screening in which four hit drugs with anti-HEV activity were identified. The results of this study provide evidence supporting the use of this system in more variable HEV studies. In addition, both forms of viral particles (eHEV-nanoKAZ and neHEV-nanoKAZ) are infectious, which will enable their application in HEV studies requiring both forms of viral particles, such as in the investigation of unknown HEV receptors and the elucidation of host factors important for HEV entry.
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26
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Induction of Hepatitis E Virus Anti-ORF3 Antibodies from Systemic Administration of a Muscle-Specific Adeno-Associated Virus (AAV) Vector. Viruses 2022; 14:v14020266. [PMID: 35215859 PMCID: PMC8878420 DOI: 10.3390/v14020266] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2021] [Revised: 01/23/2022] [Accepted: 01/24/2022] [Indexed: 01/25/2023] Open
Abstract
The hepatitis E virus (HEV) is a major global health problem, leading to large outbreaks in the developing world and chronic infections in the developed world. HEV is a non-enveloped virus, which circulates in the blood in a quasi-enveloped form. The quasi-envelope protects HEV particles from neutralising anti-capsid antibodies in the serum; however, most vaccine approaches are designed to induce an immune response against the HEV capsid. In this study, we explored systemic in vivo administration of a novel synthetic and myotropic Adeno-associated virus vector (AAVMYO3) to express the small HEV phosphoprotein ORF3 (found on quasi-enveloped HEV) in the musculature of mice, resulting in the robust and dose-dependent formation of anti-ORF3 antibodies. Neutralisation assays using the serum of ORF3 AAV-transduced mice showed a modest inhibitory effect on the infection of quasi-enveloped HEV in vivo, comparable to previously characterised anti-ORF3 antibodies used as a control. The novel AAVMYO3 capsid used in this study can serve as a versatile platform for the continued development of vector-based vaccines against HEV and other infectious agents, which could complement traditional vaccines akin to the current positive experience with SARS-CoV-2.
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27
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Qian Z, Yang C, Xu L, Mickael HK, Chen S, Zhang Y, Xia Y, Li T, Yu W, Huang F. Hepatitis E virus-encoded microRNA promotes viral replication by inhibiting type I interferon. FASEB J 2021; 36:e22104. [PMID: 34918388 DOI: 10.1096/fj.202101042r] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2021] [Revised: 11/18/2021] [Accepted: 12/01/2021] [Indexed: 02/05/2023]
Abstract
MicroRNAs (miRNAs), the non-coding RNAs of ~22 nucleotides (nt) in length, play a vital role in regulating viral replication. Hepatitis E virus (HEV), a single-stranded RNA virus, is a predominant pathogen of acute hepatitis worldwide. Virus-encoded miRNAs regulate the viral life cycle and escape from the host innate immune system. However, it is rarely known about HEV-encoded miRNA (HEV-miR-A6). In the present study, HEV-miR-A6 was screened by microarray, and further identified in vivo and in vitro. HEV-miR-A6 originated from the methylase (MeT) of HEV open reading frame 1 (ORF1) and was highly conserved in eight HEV genotypes. HEV-miR-A6 expression was growing during HEV replication, and significantly increased in acute hepatitis E patients than convalescence patients. Furthermore, HEV-miR-A6 was specifically detected in liver, spleen, kidney and colon by in situ hybridization. To identify the specificity of HEV-miR-A6, its mutants (HEV-miR-A6M1 and HEV-miR-A6M2) were constructed to change the stem-loop structure. Interestingly, over-expression of HEV-miR-A6 or HEV-miR-A6M1 significantly facilitated viral replication, while HEV-miR-A6M2, another mutant completely changed the stem-loop structure was invalid. SIRP-α, a candidate target gene of HEV-miR-A6, was activated when HEV-miR-A6 over-expressed to inhibit the phosphorylation of IRF3, and subsequently suppressed the expression of type I interferon β (IFN-β). The promotion of viral replication by HEV-miR-A6 further identified in vivo. Significant suppression of IFN-β production in the serum of HEV-infected mice pre-treated with HEV-miR-A6 was observed. In summary, HEV-miR-A6 activates SIRP-α to promote viral replication by inhibition of IFN-β expression.
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Affiliation(s)
- Zhongyao Qian
- Medical School, Kunming University of Science and Technology, Kunming, PR China
| | - Chenchen Yang
- Medical School, Kunming University of Science and Technology, Kunming, PR China
| | - Liangheng Xu
- Medical School, Kunming University of Science and Technology, Kunming, PR China
| | - Houfack K Mickael
- Medical School, Kunming University of Science and Technology, Kunming, PR China
| | - Shuangfeng Chen
- Medical School, Kunming University of Science and Technology, Kunming, PR China
| | - Yike Zhang
- Medical School, Kunming University of Science and Technology, Kunming, PR China
| | - Yueping Xia
- Medical School, Kunming University of Science and Technology, Kunming, PR China
| | - Tengyuan Li
- Medical School, Kunming University of Science and Technology, Kunming, PR China
| | - Wenhai Yu
- Institute of Medical Biology, Chinese Academy of Medical Sciences and Peking Union Medical College, Kunming, PR China
| | - Fen Huang
- Medical School, Kunming University of Science and Technology, Kunming, PR China
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28
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The Viral ORF3 Protein Is Required for Hepatitis E Virus Apical Release and Efficient Growth in Polarized Hepatocytes and Humanized Mice. J Virol 2021; 95:e0058521. [PMID: 34523963 DOI: 10.1128/jvi.00585-21] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023] Open
Abstract
Hepatitis E virus (HEV), an enterically transmitted RNA virus, is a major cause of acute hepatitis worldwide. Additionally, HEV genotype 3 (gt3) can frequently persist in immunocompromised individuals with an increased risk for developing severe liver disease. Currently, no HEV-specific treatment is available. The viral open reading frame 3 (ORF3) protein facilitates HEV egress in vitro and is essential for establishing productive infection in macaques. Thus, ORF3, which is unique to HEV, has the potential to be explored as a target for antiviral therapy. However, significant gaps exist in our understanding of the critical functions of ORF3 in HEV infection in vivo. Here, we utilized a polarized hepatocyte culture model and a human liver chimeric mouse model to dissect the roles of ORF3 in gt3 HEV release and persistent infection. We show that ORF3's absence substantially decreased HEV replication and virion release from the apical surface but not the basolateral surface of polarized hepatocytes. While wild-type HEV established a persistent infection in humanized mice, mutant HEV lacking ORF3 (ORF3null) failed to sustain the infection despite transient replication in the liver and was ultimately cleared. Strikingly, mice inoculated with the ORF3null virus displayed no fecal shedding throughout the 6-week experiment. Overall, our results demonstrate that ORF3 is required for HEV fecal shedding and persistent infection, providing a rationale for targeting ORF3 as a treatment strategy for HEV infection. IMPORTANCE HEV infections are associated with significant morbidity and mortality. HEV gt3 additionally can cause persistent infection, which can rapidly progress to liver cirrhosis. Currently, no HEV-specific treatments are available. The poorly understood HEV life cycle hampers the development of antivirals for HEV. Here, we investigated the role of the viral ORF3 protein in HEV infection in polarized hepatocyte cultures and human liver chimeric mice. We found that two major aspects of the HEV life cycle require ORF3: fecal virus shedding and persistent infection. These results provide a rationale for targeting ORF3 to treat HEV infection.
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29
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Ideno S, Inoue T, Takahashi K, Urayama T, Maeno H, Takeuchi K, Sakai K. Phenotypic characterization of cell culture-derived hepatitis E virus subjected to different chemical treatments: Application in virus removal via nanofiltration. J Virol Methods 2021; 296:114244. [PMID: 34302862 DOI: 10.1016/j.jviromet.2021.114244] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2021] [Revised: 07/15/2021] [Accepted: 07/16/2021] [Indexed: 12/23/2022]
Abstract
Safety evaluation for the hepatitis E virus (HEV) is required for plasma fractionation products. Plasma-derived HEV (pHEV) is quite unique in that it is associated with a lipid membrane, which, when stripped during manufacturing processes, induces morphological changes in the virus, making it difficult to select proper HEV phenotypes for clearance studies. We developed a convenient system for the preparation of a high titer cell culture-derived HEV (cHEV). In this system, PLC/PRF/5 cells transfected with the wild-type HEV genome generated lipid membrane-associated cHEV for a long period even after cryopreservation. We also examined how this lipid membrane-associated cHEV can be used to verify the robustness of pHEV removal via 19-nm nanofiltration. Sodium-deoxycholate and trypsin (NaDOC/T) treatment not only dissolved lipid but also digested membrane-associated proteins from pHEV and cHEV, making the resulting cHEV particle smaller in size than any pHEV phenotypes generated by ethanol or solvent-detergent treatment in this study. In both 19-nm and 35-nm nanofiltration, cHEV behaved identically to pHEV. These results indicate that cHEV is a useful resource for viral clearance studies in term of availability, and the use of NaDOC/T-treated cHEV ensured robust pHEV removal capacity via 19-nm nanofiltration.
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Affiliation(s)
- Shoji Ideno
- Central Research Laboratory, Research & Development Division, Japan Blood Products Organization, Kobe, Japan.
| | - Takamasa Inoue
- Central Research Laboratory, Research & Development Division, Japan Blood Products Organization, Kobe, Japan
| | - Kadue Takahashi
- Central Research Laboratory, Research & Development Division, Japan Blood Products Organization, Kobe, Japan
| | - Takeru Urayama
- Central Research Laboratory, Research & Development Division, Japan Blood Products Organization, Kobe, Japan
| | - Hideki Maeno
- Central Research Laboratory, Research & Development Division, Japan Blood Products Organization, Kobe, Japan
| | - Kaoru Takeuchi
- Laboratory of Environmental Microbiology, Division of Biomedical Science, Faculty of Medicine, University of Tsukuba, Tsukuba, Japan
| | - Kaoru Sakai
- Central Research Laboratory, Research & Development Division, Japan Blood Products Organization, Kobe, Japan
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30
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Glitscher M, Hildt E. Hepatitis E virus egress and beyond - the manifold roles of the viral ORF3 protein. Cell Microbiol 2021; 23:e13379. [PMID: 34272798 DOI: 10.1111/cmi.13379] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2021] [Revised: 06/18/2021] [Accepted: 07/06/2021] [Indexed: 11/30/2022]
Abstract
Although the hepatitis E virus represents an uprising threat to the global community by representing the commonest cause of an acute viral hepatitis worldwide, its life cycle is grossly understudied. Albeit HEV is a non-enveloped virus, its progeny is released as quasi-enveloped virions. Thus, the responsible accessory protein pORF3 gained rising attention in the past years. It mediates viral release via the exosomal route by targeting the viral capsid to the endosomal system, more precisely to multivesicular bodies. As this is followed by quasi-envelopment, pORF3 may in terms represent a substitute to a conventional envelope protein. This feature proofs to be rather unique with respect to other enteric viruses, although the protein's role in the viral life cycle seems to reach far beyond simply maintaining release of progeny viruses. How pORF3 affects viral morphogenesis, how it mediates efficient viral release and how it supports viral spread is summarised in this microreview. With this, we aim to shed light on functions of pORF3 to gain further insights in still enigmatic aspects of the HEV life cycle. TAKE AWAYS: HEV is released as exosome via multivesicular bodies Viral pORF3 mediates release via endosomal complexes required for transport pORF3 modulates various cellular processes in infected cells Elucidation of pORF3-related processes imply novel clinical strategies.
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Affiliation(s)
| | - Eberhard Hildt
- Department Virology, Paul-Ehrlich-Institut, Langen, Germany
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31
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Ji H, Chen S, He Q, Wang W, Gong S, Qian Z, Zhang Y, Wei D, Yu W, Huang F. The different replication between nonenveloped and quasi-enveloped hepatitis E virus. J Med Virol 2021; 93:6267-6277. [PMID: 34076903 DOI: 10.1002/jmv.27121] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2021] [Accepted: 05/31/2021] [Indexed: 12/15/2022]
Abstract
Hepatitis E virus (HEV) is the major pathogen of viral hepatitis. However, the understanding of the HEV life cycle is limited. In the present study, cells were separately infected with nonenveloped HEV (derived from feces or bile) or quasi-enveloped HEV (derived from the cell culture after serial passages, eHEV) and observed by confocal fluorescence microscopy to investigate the life cycle of HEV. HEV finished its binding and entry into host cells at first 6 h postinoculation (hpi). Cells inoculated with eHEV showed less infectivity than cells inoculated with nonenveloped HEV. Newly synthesized progeny virions were released into the supernatant of cell cultures from 48 hpi. Quantitative real-time polymerase chain reaction (qRT-PCR) and Western blot analysis results showed that the supernatant's progeny viruses were infectious even after five serial passages. These results show the significant difference between nonenveloped HEV and eHEV, which will provide novel insights into the HEV replication cycle. The efficient cell culture of HEV will promote the development of anti-HEV drugs and vaccines.
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Affiliation(s)
- Hanbin Ji
- Medical Faculty, Kunming University of Science and Technology, Kunming, PR China
| | - Shuangfeng Chen
- Medical Faculty, Kunming University of Science and Technology, Kunming, PR China
| | - Qiuxia He
- Medical Faculty, Kunming University of Science and Technology, Kunming, PR China
| | - Wenjing Wang
- Medical Faculty, Kunming University of Science and Technology, Kunming, PR China
| | - Shilin Gong
- Medical Faculty, Kunming University of Science and Technology, Kunming, PR China
| | - Zhongyao Qian
- Medical Faculty, Kunming University of Science and Technology, Kunming, PR China
| | - Yike Zhang
- Medical Faculty, Kunming University of Science and Technology, Kunming, PR China
| | - Daqiao Wei
- Medical Faculty, Kunming University of Science and Technology, Kunming, PR China
| | - Wenhai Yu
- Institute of Medical Biology, Chinese Academy of Medical Sciences and Peking Union Medical College, Kunming, PR China
| | - Fen Huang
- Medical Faculty, Kunming University of Science and Technology, Kunming, PR China.,Yunnan Provincial Key Laboratory of Clinical Virology, Kunming, PR China
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32
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Yang YL, Nan YC. Open reading frame 3 protein of hepatitis E virus: Multi-function protein with endless potential. World J Gastroenterol 2021; 27:2458-2473. [PMID: 34092969 PMCID: PMC8160619 DOI: 10.3748/wjg.v27.i20.2458] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/27/2021] [Revised: 03/10/2021] [Accepted: 04/12/2021] [Indexed: 02/06/2023] Open
Abstract
Hepatitis E virus (HEV), a fecal-orally transmitted foodborne viral pathogen, causes acute hepatitis in humans and is responsible for hepatitis E outbreaks worldwide. Since the identification of HEV as a zoonotic agent, this virus has been isolated from a variety of hosts with an ever-expanding host range. HEV-open reading frame (ORF) 3, the smallest ORF in HEV genomes, initially had been perceived as an unremarkable HEV accessory protein. However, as novel HEV-ORF3 function has been discovered that is related to the existence of a putative third virion structural form, referred to as “quasi-enveloped” HEV particles, HEV is challenging the conventional virion structure-based classification scheme, which assigns all viruses to two groups, “enveloped” or “non-enveloped”. In this review, we systematically describe recent progress that has identified multiple pathogenic roles of HEV-ORF3, including roles in HEV virion release, biogenesis of quasi-enveloped virus, regulation of the host innate immune response, and interference with host signaling pathways. In addition, implications of HEV-ORF3-associated quasi-enveloped virions are discussed to guide future development of improved vaccines against zoonotic HEV infection.
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Affiliation(s)
- Yong-Lin Yang
- Department of Infectious Diseases, Taizhou People's Hospital, The Fifth Affiliated Hospital of Nantong University, Taizhou 225300, Jiangsu Province, China
- Department of General Practice, Nanjing First Hospital, Nanjing Medical University, Nanjing 210006, Jiangsu Province, China
| | - Yu-Chen Nan
- Department of Preventive Veterinary Medicine, Northwest A&F University, Yangling 712100, Shaanxi Province, China
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Mechanism of Cross-Species Transmission, Adaptive Evolution and Pathogenesis of Hepatitis E Virus. Viruses 2021; 13:v13050909. [PMID: 34069006 PMCID: PMC8157021 DOI: 10.3390/v13050909] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2021] [Revised: 05/12/2021] [Accepted: 05/13/2021] [Indexed: 12/17/2022] Open
Abstract
Hepatitis E virus (HEV) is the leading cause of acute hepatitis worldwide. While the transmission in developing countries is dominated by fecal-oral route via drinking contaminated water, the zoonotic transmission is the major route of HEV infection in industrialized countries. The discovery of new HEV strains in a growing number of animal species poses a risk to zoonotic infection. However, the exact mechanism and the determinant factors of zoonotic infection are not completely understood. This review will discuss the current knowledge on the mechanism of cross-species transmission of HEV infection, including viral determinants, such as the open reading frames (ORFs), codon usage and adaptive evolution, as well as host determinants, such as host cellular factors and the host immune status, which possibly play pivotal roles during this event. The pathogenesis of hepatitis E infection will be briefly discussed, including the special forms of this disease, including extrahepatic manifestations, chronic infection, and fulminant hepatitis in pregnant women.
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Jiao H, Shuai X, Luo Y, Zhou Z, Zhao Y, Li B, Gu G, Li W, Li M, Zeng H, Guo X, Xiao Y, Song Z, Gan L, Huang Q. Deep Insight Into Long Non-coding RNA and mRNA Transcriptome Profiling in HepG2 Cells Expressing Genotype IV Swine Hepatitis E Virus ORF3. Front Vet Sci 2021; 8:625609. [PMID: 33996960 PMCID: PMC8116512 DOI: 10.3389/fvets.2021.625609] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2020] [Accepted: 03/10/2021] [Indexed: 12/14/2022] Open
Abstract
Swine hepatitis E (swine HE) is a new type of zoonotic infectious disease caused by the swine hepatitis E virus (swine HEV). Open reading frame 3 (ORF3) is an important virulent protein of swine HEV, but its function still is mainly unclear. In this study, we generated adenoviruses ADV4-ORF3 and ADV4 negative control (ADV4-NC), which successfully mediated overexpression of enhanced green fluorescent protein (EGFP)-ORF3 and EGFP, respectively, in HepG2 cells. High-throughput sequencing was used to screen for differentially expressed long non-coding RNAs (lncRNAs) and messenger RNAs (mRNAs). The cis-target genes of lncRNAs were predicted, functional enrichment (Gene Ontology [GO] and Kyoto Encyclopedia of Genes and Genomes [KEGG]) was performed, and 12 lncRNAs with statistically significant different expressions (p ≤ 0.05 and q ≤ 1) were selected for further quantitative real-time reverse transcription (qRT-PCR) validation. In HepG2 cells, we identified 62 significantly differentially expressed genes (DEGs) (6,564 transcripts) and 319 lncRNAs (124 known lncRNAs and 195 novel lncRNAs) that were affected by ORF3, which were involved in systemic lupus erythematosus, Staphylococcus aureus infection, signaling pathways pluripotency regulation of stem cells, the peroxisome proliferator-activated receptor (PPAR) signaling pathway, and platinum drug resistance pathways. Cis-target gene prediction identified 45 lncRNAs corresponding to candidate mRNAs, among which eight were validated by qRT-PCR: LINC02476 (two transcripts), RAP2C-AS1, AC016526, AL139099, and ZNF337-AS1 (3 transcripts). Our results revealed that the lncRNA profile in host cells affected by ORF3, swine HEV ORF3, might affect the pentose and glucuronate interconversions and mediate the formation of obstructive jaundice by influencing bile secretion, which will help to determine the function of ORF3 and the infection mechanism and treatment of swine HE.
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Affiliation(s)
- Hanwei Jiao
- College of Veterinary Medicine, Southwest University, Chongqing, China.,Immunology Research Center, Medical Research Institute, Southwest University, Chongqing, China.,Chongqing Veterinary Scientific Engineering Research Center, Southwest University, Chongqing, China
| | - Xuehong Shuai
- College of Veterinary Medicine, Southwest University, Chongqing, China.,Immunology Research Center, Medical Research Institute, Southwest University, Chongqing, China.,Chongqing Veterinary Scientific Engineering Research Center, Southwest University, Chongqing, China
| | - Yichen Luo
- College of Veterinary Medicine, Southwest University, Chongqing, China.,Immunology Research Center, Medical Research Institute, Southwest University, Chongqing, China.,Chongqing Veterinary Scientific Engineering Research Center, Southwest University, Chongqing, China
| | - Zhixiong Zhou
- College of Veterinary Medicine, Southwest University, Chongqing, China
| | - Yu Zhao
- College of Veterinary Medicine, Southwest University, Chongqing, China.,Institute of Animal Husbandry and Veterinary Medicine of Guizhou Academy of Agricultural Science, Guiyang, China
| | - Bowen Li
- College of Veterinary Medicine, Southwest University, Chongqing, China
| | - Guojing Gu
- College of Veterinary Medicine, Southwest University, Chongqing, China
| | - Wenjie Li
- College of Veterinary Medicine, Southwest University, Chongqing, China
| | - Mengjuan Li
- College of Veterinary Medicine, Southwest University, Chongqing, China
| | - Hui Zeng
- College of Veterinary Medicine, Southwest University, Chongqing, China
| | - Xiaoyi Guo
- College of Veterinary Medicine, Southwest University, Chongqing, China
| | - Yu Xiao
- College of Veterinary Medicine, Southwest University, Chongqing, China
| | - Zhenhui Song
- College of Veterinary Medicine, Southwest University, Chongqing, China.,Immunology Research Center, Medical Research Institute, Southwest University, Chongqing, China.,Chongqing Veterinary Scientific Engineering Research Center, Southwest University, Chongqing, China
| | - Ling Gan
- College of Veterinary Medicine, Southwest University, Chongqing, China.,Immunology Research Center, Medical Research Institute, Southwest University, Chongqing, China.,Chongqing Veterinary Scientific Engineering Research Center, Southwest University, Chongqing, China
| | - Qingzhou Huang
- College of Veterinary Medicine, Southwest University, Chongqing, China.,Chongqing Veterinary Scientific Engineering Research Center, Southwest University, Chongqing, China
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Owusu IA, Quaye O, Passalacqua KD, Wobus CE. Egress of non-enveloped enteric RNA viruses. J Gen Virol 2021; 102:001557. [PMID: 33560198 PMCID: PMC8515858 DOI: 10.1099/jgv.0.001557] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2020] [Accepted: 01/04/2021] [Indexed: 12/27/2022] Open
Abstract
A long-standing paradigm in virology was that non-enveloped viruses induce cell lysis to release progeny virions. However, emerging evidence indicates that some non-enveloped viruses exit cells without inducing cell lysis, while others engage both lytic and non-lytic egress mechanisms. Enteric viruses are transmitted via the faecal-oral route and are important causes of a wide range of human infections, both gastrointestinal and extra-intestinal. Virus cellular egress, when fully understood, may be a relevant target for antiviral therapies, which could minimize the public health impact of these infections. In this review, we outline lytic and non-lytic cell egress mechanisms of non-enveloped enteric RNA viruses belonging to five families: Picornaviridae, Reoviridae, Caliciviridae, Astroviridae and Hepeviridae. We discuss factors that contribute to egress mechanisms and the relevance of these mechanisms to virion stability, infectivity and transmission. Since most data were obtained in traditional two-dimensional cell cultures, we will further attempt to place them into the context of polarized cultures and in vivo pathogenesis. Throughout the review, we highlight numerous knowledge gaps to stimulate future research into the egress mechanisms of these highly prevalent but largely understudied viruses.
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Affiliation(s)
- Irene A. Owusu
- Department of Microbiology and Immunology, University of Michigan Medical School, Ann Arbor, MI 48109-5620, USA
- West African Centre for Cell Biology of Infectious Pathogens, Department of Biochemistry, Cell and Molecular Biology, University of Ghana, Legon, Accra, Ghana
| | - Osbourne Quaye
- West African Centre for Cell Biology of Infectious Pathogens, Department of Biochemistry, Cell and Molecular Biology, University of Ghana, Legon, Accra, Ghana
| | - Karla D. Passalacqua
- Department of Microbiology and Immunology, University of Michigan Medical School, Ann Arbor, MI 48109-5620, USA
- Henry Ford Health System, Detroit, MI 48202, USA
| | - Christiane E. Wobus
- Department of Microbiology and Immunology, University of Michigan Medical School, Ann Arbor, MI 48109-5620, USA
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36
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Belei O, Ancusa O, Mara A, Olariu L, Amaricai E, Folescu R, Zamfir CL, Gurgus D, Motoc AG, Stânga LC, Strat L, Marginean O. Current Paradigm of Hepatitis E Virus Among Pediatric and Adult Patients. Front Pediatr 2021; 9:721918. [PMID: 34660485 PMCID: PMC8515027 DOI: 10.3389/fped.2021.721918] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/07/2021] [Accepted: 08/31/2021] [Indexed: 12/26/2022] Open
Abstract
Hepatitis E virus (HEV) infection is a polymorphic condition, present throughout the world and involving children and adults. Multiple studies over the last decade have contributed to a better understanding of the natural evolution of this infection in various population groups, several reservoirs and transmission routes being identified. To date, acute or chronic HEV-induced hepatitis has in some cases remained underdiagnosed due to the lower accuracy of serological tests and due to the evolutionary possibility with extrahepatic manifestations. Implementation of diagnostic tests based on nucleic acid analysis has increased the detection rate of this disease. The epidemiological and clinical features of HEV hepatitis differ depending on the geographical areas studied. HEV infection is usually a self-limiting condition in immunocompetent patients, but in certain categories of vulnerable patients it can induce a sudden evolution toward acute liver failure (pregnant women) or chronicity (immunosuppressed patients, post-transplant, hematological, or malignant diseases). In acute HEV infections in most cases supportive treatment is sufficient. In patients who develop chronic hepatitis with HEV, dose reduction of immunosuppressive medication should be the first therapeutic step, especially in patients with transplant. In case of unfavorable response, the initiation of antiviral therapy is recommended. In this review, the authors summarized the essential published data related to the epidemiological, clinical, paraclinical, and therapeutic aspects of HEV infection in adult and pediatric patients.
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Affiliation(s)
- Oana Belei
- First Pediatric Clinic, Disturbance of Growth and Development on Children Research Center, "Victor Babes" University of Medicine and Pharmacy, Timisoara, Romania
| | - Oana Ancusa
- Fifth Department of Internal Medicine, "Victor Babes" University of Medicine and Pharmacy, Timisoara, Romania
| | - Adelina Mara
- Department of Internal Medicine, Emergency City Hospital, Timisoara, Romania
| | - Laura Olariu
- First Pediatric Clinic, "Victor Babes" University of Medicine and Pharmacy, Timisoara, Romania
| | - Elena Amaricai
- Department of Rehabilitation Physical Medicine and Rheumatology, "Victor Babes" University of Medicine and Pharmacy, Timisoara, Romania
| | - Roxana Folescu
- Department of Balneology, Medical Recovery and Rheumatology, Family Discipline, Center for Preventive Medicine, "Victor Babes" University of Medicine and Pharmacy, Timisoara, Romania
| | - Carmen Lacramioara Zamfir
- Department of Morpho-Functional Sciences I, "Grigore T. Popa" University of Medicine and Pharmacy, Iasi, Romania
| | - Daniela Gurgus
- Department of Balneology, Medical Recovery and Rheumatology, Family Discipline, Center for Preventive Medicine, "Victor Babes" University of Medicine and Pharmacy, Timisoara, Romania
| | - Andrei G Motoc
- Department of Anatomy and Embriology, "Victor Babes" University of Medicine and Pharmacy, Timisoara, Romania
| | - Livia Claudia Stânga
- Department of Microbiology, "Victor Babes" University of Medicine and Pharmacy, Timisoara, Romania
| | - Liliana Strat
- Department of Mother and Child Medicine, "Grigore T. Popa" University of Medicine and Pharmacy, Iasi, Romania
| | - Otilia Marginean
- First Pediatric Clinic, Disturbance of Growth and Development on Children Research Center, "Victor Babes" University of Medicine and Pharmacy, Timisoara, Romania
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Tallan A, Feng Z. Virus spread in the liver: mechanisms, commonalities, and unanswered questions. Future Virol 2020; 15:707-715. [PMID: 33250929 DOI: 10.2217/fvl-2020-0158] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2020] [Accepted: 09/28/2020] [Indexed: 12/11/2022]
Abstract
The liver is home to five known human hepatitis viruses (hepatitis A virus-hepatitis E virus). Despite being phylogenetically unrelated, these viruses replicate and spread in the liver without causing apparent cytopathic effects, and all have evolved strategies to counteract antibody-mediated inhibition of virus spread. In this review, we discuss the current understanding regarding the spread mechanisms for these viruses with an attempt to extract common principles and identify key questions for future studies.
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Affiliation(s)
- Alexi Tallan
- Center for Vaccines & Immunity, The Abigail Wexner Research Institute at Nationwide Children's Hospital, Columbus, OH 43205, USA
| | - Zongdi Feng
- Center for Vaccines & Immunity, The Abigail Wexner Research Institute at Nationwide Children's Hospital, Columbus, OH 43205, USA.,Department of Pediatrics, Ohio State University College of Medicine, Columbus OH 43210, USA
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38
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Abstract
Hepatitis A virus (HAV) and hepatitis E virus (HEV) infections are the main causes for acute hepatitis worldwide. Both viruses had long been considered as nonenveloped viruses. However, recent work has uncovered that both viruses circulate in the bloodstream as membrane-cloaked, "quasi-enveloped" particles that are, surprisingly, infectious and likely the only form mediating virus spread within the host. The discovery of quasi-enveloped HAV and HEV particles has fundamentally changed the traditional view on the life cycle and pathogenesis of these viruses. However, because HAV and HEV are phylogenetically unrelated and their capsid assembly processes are quite distinct, it is not clear whether they use similar or different mechanisms for envelopment and exit. This review provides an overview of the current knowledge about the assembly and exit processes of HAV and HEV and perspectives for future studies.
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Affiliation(s)
- Zongdi Feng
- Center for Vaccines and Immunity, The Abigail Wexner Research Institute at Nationwide Children's Hospital, Columbus, OH, United States; Department of Pediatrics, Ohio State University College of Medicine, Columbus, OH, United States.
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39
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Muñoz-Chimeno M, Cenalmor A, Garcia-Lugo MA, Hernandez M, Rodriguez-Lazaro D, Avellon A. Proline-Rich Hypervariable Region of Hepatitis E Virus: Arranging the Disorder. Microorganisms 2020; 8:microorganisms8091417. [PMID: 32942608 PMCID: PMC7564002 DOI: 10.3390/microorganisms8091417] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2020] [Revised: 08/21/2020] [Accepted: 09/11/2020] [Indexed: 12/15/2022] Open
Abstract
The hepatitis E virus (HEV) hypervariable region (HVR) presents the highest divergence of the entire HEV genome. It is characteristically rich in proline, and so is also known as the “polyproline region” (PPR). HEV genotype 3 (HEV-3) exhibits different PPR lengths due to insertions, PPR and/or RNA-dependent RNA polymerase (RdRp) duplications and deletions. A total of 723 PPR-HEV sequences were analyzed, of which 137 HEV-3 sequences were obtained from clinical specimens (from acute and chronic infection) by Sanger sequencing. Eight swine stool/liver samples were also analyzed. N- and C-terminal fragments were confirmed as being conserved, but they harbored differences between genotypes and were not proline-plentiful regions. The genuine PPR is the intermediate region between them. HEV-3 PPR contains a higher percentage (30.4%) of prolines than other genotypes. We describe for the first time: (1) the specific placement of HEV-3 PPR rearrangements in sites 1 to 14 of the PPR, noting that duplications are more frequently attached to sites 11 and 12 (AAs 74–79 and 113–118, respectively); (2) the cadence of repetitions follows a circular-like pattern of blocks A to J, with F, G, H, and I being the most frequent; (3) a previously unreported insertion homologous to apolipoprotein C1; and (4) the increase in frequency of potential N-glycosylation sites and differences in AAs composition related to duplications.
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Affiliation(s)
- Milagros Muñoz-Chimeno
- Hepatitis Unit, National Center of Microbiology, Carlos III Institute of Health, 28220 Madrid, Spain; (M.M.-C.); (A.C.); (M.A.G.-L.)
| | - Alejandro Cenalmor
- Hepatitis Unit, National Center of Microbiology, Carlos III Institute of Health, 28220 Madrid, Spain; (M.M.-C.); (A.C.); (M.A.G.-L.)
| | - Maira Alejandra Garcia-Lugo
- Hepatitis Unit, National Center of Microbiology, Carlos III Institute of Health, 28220 Madrid, Spain; (M.M.-C.); (A.C.); (M.A.G.-L.)
| | - Marta Hernandez
- Laboratorio de Biología Molecular y Microbiología, Instituto Tecnológico Agrario de Castilla y León (ITACyL), 47071 Valladolid, Spain;
- Microbiology Division, Faculty of Sciences, University of Burgos, 09001 Burgos, Spain;
| | | | - Ana Avellon
- Hepatitis Unit, National Center of Microbiology, Carlos III Institute of Health, 28220 Madrid, Spain; (M.M.-C.); (A.C.); (M.A.G.-L.)
- CIBER Epidemiology and Public Health, 28029 Madrid, Spain
- Correspondence:
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40
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Virus-Host Cell Interplay during Hepatitis E Virus Infection. Trends Microbiol 2020; 29:309-319. [PMID: 32828646 PMCID: PMC7437515 DOI: 10.1016/j.tim.2020.07.002] [Citation(s) in RCA: 35] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2020] [Revised: 06/26/2020] [Accepted: 07/22/2020] [Indexed: 12/11/2022]
Abstract
The molecular interplay between cellular host factors and viral proteins is a continuous process throughout the viral life cycle determining virus host range and pathogenesis. The hepatitis E virus (HEV) is a long-neglected RNA virus and the major causative agent of acute viral hepatitis in humans worldwide. However, the mechanisms of liver pathology and clinical disease remain poorly understood for HEV infection. This review summarizes our current understanding of HEV-host cell interactions and highlights experimental strategies and techniques to identify novel host components required for the viral life cycle as well as restriction factors. Understanding these interactions will provide insight into the viral life cycle of HEV and might further help to devise novel therapeutic strategies and antiviral targets.
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41
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Scholz J, Falkenhagen A, Bock CT, Johne R. Reverse genetics approaches for hepatitis E virus and related viruses. Curr Opin Virol 2020; 44:121-128. [PMID: 32818718 DOI: 10.1016/j.coviro.2020.07.004] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2020] [Revised: 06/05/2020] [Accepted: 07/06/2020] [Indexed: 12/19/2022]
Abstract
The hepatitis E virus (HEV) is the causative agent of acute and chronic hepatitis in humans. Related viruses have been found in several animal species. Reverse genetics systems (RGSs), which enable the generation of infectious virus from cloned cDNA by transfection of cultured cells or intrahepatic injection into laboratory animals, have been developed for HEV genotypes 1, 3, 4, 5 and 7 as well as for avian HEV and rat HEV. However, low virus recovery rates and slow replication in cell cultures are observed for most of the HEV types. Nevertheless, the RGSs enabled the site-directed mutagenesis of single nucleotides, deletion of genome fragments, insertion of sequence tags and a marker gene as well as the generation of chimeric viruses.
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Affiliation(s)
- Johannes Scholz
- Department Biological Safety, German Federal Institute for Risk Assessment, Berlin, Germany
| | - Alexander Falkenhagen
- Department Biological Safety, German Federal Institute for Risk Assessment, Berlin, Germany
| | - Claus-Thomas Bock
- Division of Viral Gastroenteritis and Hepatitis Pathogens and Enteroviruses, Department of Infectious Diseases, Robert Koch Institute, Berlin, Germany
| | - Reimar Johne
- Department Biological Safety, German Federal Institute for Risk Assessment, Berlin, Germany.
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Kumar M, Hooda P, Khanna M, Patel U, Sehgal D. Development of BacMam Induced Hepatitis E Virus Replication Model in Hepatoma Cells to Study the Polyprotein Processing. Front Microbiol 2020; 11:1347. [PMID: 32625196 PMCID: PMC7315041 DOI: 10.3389/fmicb.2020.01347] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2020] [Accepted: 05/26/2020] [Indexed: 01/10/2023] Open
Abstract
The processing of polyprotein(s) to form structural and non-structural components remains an enigma due to the non-existence of an efficient and robust Hepatitis E Virus (HEV) culture system. We used the BacMam approach to construct an HEV replication model in which the HEV genome was cloned in the BacMam vector under the CMV promoter. The recombinant BacMam was used to infect Huh7 cells to transfer the HEV genome. HEV replication was authenticated by the presence of RNAs of both the polarity (+) and (−) and formation of hybrid RNA, a replication intermediate. The presence of genes for Papain-like Cysteine Protease (PCP), methyltransferase (MeT), RNA dependent RNA polymerase (RdRp), and ORF2 was confirmed by PCR amplification. Further, the infectious nature of the culture system was established as evidenced by the cross-infection of uninfected cells using the cell lysate from the infected cells. The HEV replication model was validated by detection of the ORF1 (Open Reading Frame1) encoded proteins, identified by Western blotting and Immunofluorescence by using epitope-specific antibodies against each protein. Consequently, discrete bands of 18, 35, 37, and 56 kDa corresponding to PCP, MeT, RdRp, and ORF2, respectively, were seen. Besides demonstrating the presence of non-structural enzymes of HEV along with ORF2, activity of a key enzyme, HEV-methyltransferase has also been observed. A 20% decrease in the replicative forms of RNA could be seen in presence of 100 μM Ribavirin after 48 h of treatment. The inhibition gradually increased from 0 to 24 to 48 h post-treatment. Summarily, infectious HEV culture system has been established, which could demonstrate the presence of HEV replicative RNA forms, the structural and non-structural proteins and the methyltransferase in its active form. The system may also be used to study the mechanism of action of Ribavirin in inhibiting HEV replication and develop a therapy.
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Affiliation(s)
- Manjeet Kumar
- Virology Laboratory, Department of Life Sciences, Shiv Nadar University, Greater Noida, India
| | - Preeti Hooda
- Virology Laboratory, Department of Life Sciences, Shiv Nadar University, Greater Noida, India
| | - Madhu Khanna
- Virology Lab, Department of Virology, Vallabhbhai Patel Chest Institute, University of Delhi, New Delhi, India
| | - Utkarsh Patel
- Virology Laboratory, Department of Life Sciences, Shiv Nadar University, Greater Noida, India
| | - Deepak Sehgal
- Virology Laboratory, Department of Life Sciences, Shiv Nadar University, Greater Noida, India
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43
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On the Host Side of the Hepatitis E Virus Life Cycle. Cells 2020; 9:cells9051294. [PMID: 32456000 PMCID: PMC7291229 DOI: 10.3390/cells9051294] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2020] [Revised: 05/20/2020] [Accepted: 05/21/2020] [Indexed: 12/12/2022] Open
Abstract
Hepatitis E virus (HEV) infection is one of the most common causes of acute hepatitis in the world. HEV is an enterically transmitted positive-strand RNA virus found as a non-enveloped particle in bile as well as stool and as a quasi-enveloped particle in blood. Current understanding of the molecular mechanisms and host factors involved in productive HEV infection is incomplete, but recently developed model systems have facilitated rapid progress in this area. Here, we provide an overview of the HEV life cycle with a focus on the host factors required for viral entry, RNA replication, assembly and release. Further developments of HEV model systems and novel technologies should yield a broader picture in the future.
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44
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Ju X, Xiang G, Gong M, Yang R, Qin J, Li Y, Nan Y, Yang Y, Zhang QC, Ding Q. Identification of functional cis-acting RNA elements in the hepatitis E virus genome required for viral replication. PLoS Pathog 2020; 16:e1008488. [PMID: 32433693 PMCID: PMC7239442 DOI: 10.1371/journal.ppat.1008488] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2019] [Accepted: 03/22/2020] [Indexed: 12/29/2022] Open
Abstract
There are approximately 20 million events of hepatitis E virus (HEV) infection worldwide annually. The genome of HEV is a single-strand, positive-sense RNA containing 5’ and 3’ untranslated regions and three open reading frames (ORF). HEV genome has 5’ cap and 3’ poly(A) tail to mimic host mRNA to escape the host innate immune surveillance and utilize host translational machineries for viral protein translation. The replication mechanism of HEV is poorly understood, especially how the viral polymerase distinguishes viral RNA from host mRNA to synthesize new viral genomes. We hypothesize that the HEV genome contains cis-acting elements that can be recognized by the virally encoded polymerase as “self” for replication. To identify functional cis-acting elements systematically across the HEV genome, we utilized an ORF1 transcomplementation system. Ultimately, we found two highly conserved cis-acting RNA elements within the ORF1 and ORF2 coding regions that are required for viral genome replication in a diverse panel of HEV genotypes. Synonymous mutations in the cis-acting RNA elements, not altering the ORF1 and ORF2 protein sequences, significantly impaired production of infectious viral particles. Mechanistic studies revealed that the cis-acting elements form secondary structures needed to interact with the HEV ORF1 protein to promote HEV replication. Thus, these cis-acting elements function as a scaffold, providing a specific “signal” that recruits viral and host factors to assemble the viral replication complex. Altogether, this work not only facilitates our understanding of the HEV life cycle and provides novel, RNA-directed targets for potential HEV treatments, but also sheds light on the development of HEV as a therapeutic delivery vector. Hepatitis E virus (HEV) is an underestimated pathogen, causing approximately 20 million infections worldwide annually and leading to about 60,000 deaths. There are no direct-acting antivirals for treating HEV, and although significant progress has been made to establish robust HEV cell culture models, the life cycle remains poorly characterized. A better understanding of HEV replication could facilitate the development of new drugs targeting this critical process. Our study found that RNA elements in the HEV genome interact with the HEV replicases to promote viral replication, suggesting that these RNA elements function as a scaffold for recruitment and assembly of the viral replication complex. This work furthers our understanding of HEV replication and could inform the generation of RNA-based therapeutics for treating HEV infection.
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Affiliation(s)
- Xiaohui Ju
- Center for Infectious Disease Research, School of Medicine, Tsinghua University, Beijing, China
| | - Guangtao Xiang
- Center for Infectious Disease Research, School of Medicine, Tsinghua University, Beijing, China
| | - Mingli Gong
- Center for Infectious Disease Research, School of Medicine, Tsinghua University, Beijing, China
| | - Rui Yang
- School of Life Sciences, Tsinghua University, Beijing, China
| | - Jierui Qin
- Center for Infectious Disease Research, School of Medicine, Tsinghua University, Beijing, China
| | - Yafei Li
- Department of Preventive Veterinary Medicine, College of Veterinary Medicine, Northwest A&F University, Yangling, Shaanxi, China
| | - Yuchen Nan
- Department of Preventive Veterinary Medicine, College of Veterinary Medicine, Northwest A&F University, Yangling, Shaanxi, China
| | - Yonglin Yang
- Department of General Practice, Nanjing First Hospital, Nanjing Medical University, Nanjing, China
| | - Qiangfeng Cliff Zhang
- School of Life Sciences, Tsinghua University, Beijing, China
- Beijing Advanced Innovation Center for Structural Biology, Tsinghua University, Beijing, China
| | - Qiang Ding
- Center for Infectious Disease Research, School of Medicine, Tsinghua University, Beijing, China
- Beijing Advanced Innovation Center for Structural Biology, Tsinghua University, Beijing, China
- * E-mail:
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45
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Wallace SJ, Crossan C, Hussaini SH, Dalton HR. Hepatitis E: a largely underestimated, emerging threat. Br J Hosp Med (Lond) 2020; 80:399-404. [PMID: 31283400 DOI: 10.12968/hmed.2019.80.7.399] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Hepatitis E virus has two distinct clinical and epidemiological patterns based on the varying genotypes. Genotypes 3 and 4 cause widespread, sporadic infection in high-income countries and are emerging as the most common type of viral hepatitis in much of Europe. These infections carry significant morbidity and mortality in the growing numbers of immunosuppressed patients or in patients with established liver disease. Furthermore the growing extra-hepatic associations of the virus, including neurological and kidney injury, suggest that it may have been misnamed as a 'hepatitis' virus. This review explores current understanding of the epidemiology, virology and clinical presentations of hepatitis E infection and identifies vulnerable patient groups, who are at serious risk from infection. Guidance is offered regarding the diagnosis, treatment and prevention of this growing public health hazard.
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Affiliation(s)
- S J Wallace
- Speciality Registrar, Department of Gastroenterology, Aberdeen Royal Infirmary, Aberdeen AB25 2ZN
| | - C Crossan
- Research Fellow, Department of Life Sciences, Glasgow Caledonian University, Glasgow
| | - S H Hussaini
- Consultant, Department of Gastroenterology, Royal Cornwall Hospital, Truro, Cornwall
| | - H R Dalton
- Retired Consultant, Department of Gastroenterology, Royal Cornwall Hospital, Truro, Cornwall
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Saraswat S, Chaudhary M, Sehgal D. Hepatitis E Virus Cysteine Protease Has Papain Like Properties Validated by in silico Modeling and Cell-Free Inhibition Assays. Front Cell Infect Microbiol 2020; 9:478. [PMID: 32039053 PMCID: PMC6989534 DOI: 10.3389/fcimb.2019.00478] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2019] [Accepted: 12/27/2019] [Indexed: 12/11/2022] Open
Abstract
Hepatitis E virus (HEV) has emerged as a global health concern during the last decade. In spite of a high mortality rate in pregnant women with fulminant hepatitis, no antiviral drugs or licensed vaccine is available in India. HEV-protease is a pivotal enzyme responsible for ORF1 polyprotein processing leading to cleavage of the non-structural enzymes involved in virus replication. HEV-protease region encoding 432–592 amino acids of Genotype-1 was amplified, expressed in Sf21 cells and purified in its native form. The recombinant enzyme was biochemically characterized using SDS-PAGE, Western blotting and Immunofluorescence. The enzyme activity and the inhibition studies were conducted using Zymography, FTC-casein based protease assay and ORF1 polyprotein digestion. To conduct ORF1 digestion assay, the polyprotein, natural substrate of HEV-protease, was expressed in E. coli and purified. Cleavage of 186 kDa ORF1 polyprotein by the recombinant HEV-protease lead to appearance of non-structural proteins viz. Methyltransferase, Protease, Helicase and RNA dependent RNA polymerase which were confirmed through immunoblotting using antibodies generated against specific epitopes of the enzymes. FTC-casein substrate was used for kinetic studies to determine Km and Vmax of the enzyme and also the effect of different metal ions and other protease inhibitors. A 95% inhibition was observed with E-64 which was validated through in silico analysis. The correlation coefficient between inhibition and docking score of Inhibitors was found to have a significant value of r2 = 0.75. The predicted 3D model showed two domain architecture structures similar to Papain like cysteine protease though they differed in arrangements of alpha helices and beta sheets. Hence, we propose that HEV-protease has characteristics of “Papain-like cysteine protease,” as determined through structural homology, active site residues and class-specific inhibition. However, conclusive nature of the enzyme remains to be established.
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Affiliation(s)
- Shweta Saraswat
- Virology Lab, Department of Life Sciences, Shiv Nadar University, Greater Noida, India
| | - Meenakshi Chaudhary
- Virology Lab, Department of Life Sciences, Shiv Nadar University, Greater Noida, India
| | - Deepak Sehgal
- Virology Lab, Department of Life Sciences, Shiv Nadar University, Greater Noida, India
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Multivesicular body sorting and the exosomal pathway are required for the release of rat hepatitis E virus from infected cells. Virus Res 2020; 278:197868. [PMID: 31962066 DOI: 10.1016/j.virusres.2020.197868] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2019] [Revised: 01/17/2020] [Accepted: 01/17/2020] [Indexed: 01/14/2023]
Abstract
Recent reports have shown that rat hepatitis E virus (HEV) is capable of infecting humans. We also successfully propagated rat HEV into human PLC/PRF/5 cells, raising the possibility of a similar mechanism shared by human HEV and rat HEV. Rat HEV has the proline-rich sequence, PxYPMP, in the open reading frame 3 (ORF3) protein that is indispensable for its release. However, the release mechanism remains unclear. The overexpression of dominant-negative (DN) mutant of vacuolar protein sorting (Vps)4A or Vps4B decreased rat HEV release to 23.9 % and 18.0 %, respectively. The release of rat HEV was decreased to 8.3 % in tumor susceptibility gene 101 (Tsg101)-depleted cells and to 31.5 % in apoptosis-linked gene 2-interacting protein X (Alix)-depleted cells. Although rat HEV ORF3 protein did not bind to Tsg101, we found a 90-kDa protein capable of binding to wild-type rat HEV ORF3 protein but not to ORF3 mutant with proline to leucine mutations in the PxYPMP motif. Rat HEV release was also decreased in Ras-associated binding 27A (Rab27A)- or hepatocyte growth factor-regulated tyrosine kinase substrate (Hrs)-depleted cells (to 20.1 % and 18.5 %, respectively). In addition, the extracellular rat HEV levels in the infected PLC/PRF/5 cells were increased after treatment with Bafilomycin A1 and decreased after treatment with GW4869. These results indicate that rat HEV utilizes multivesicular body (MVB) sorting for its release and that the exosomal pathway is required for rat HEV egress. A host protein alternative to Tsg101 that can bind to rat HEV ORF3 should be explored in further study.
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Sayed IM, Meuleman P. Updates in Hepatitis E virus (HEV) field; lessons learned from human liver chimeric mice. Rev Med Virol 2019; 30:e2086. [PMID: 31835277 DOI: 10.1002/rmv.2086] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2019] [Revised: 09/09/2019] [Accepted: 09/11/2019] [Indexed: 12/14/2022]
Abstract
Hepatitis E virus (HEV) is the most common cause of viral hepatitis globally, and it is an emerging pathogen in developed countries. In vivo studies of HEV have long been hindered due to the lack of an efficient small animal model. Recently, human liver chimeric mice were described as an elegant model to study chronic HEV infection. HEV infection was established in mice with humanized liver that were challenged with stool preparations containing HEV genotype (gt)1 and/or gt3. An increase in viral load and the level of HEV Ag in mouse samples were markers of active infection. Plasma-derived HEV preparations were less infectious. The kinetics of HEV ORF2 Ag during HEV infection and its impact on HEV diagnosis were described in this model. In addition, the nature of HEV particles and HEV ORF2 Ag were characterized. Moreover, humanized mice were used to study the impact of HEV infection on the hepatic innate transcriptome and evaluation of anti-HEV therapies. This review highlights recent advances in the HEV field gathered from well-established experimental mouse models, with an emphasis on this model as a tool for elucidating the course of HEV infection, the study of the HEV life cycle, the interaction of the virus with the host, and the evaluation of new anti-HEV therapies.
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Affiliation(s)
- Ibrahim M Sayed
- Department of Pathology, School of Medicine, University of California, San Diego, San Diego, California, USA.,Microbiology and Immunology Department, Faculty of Medicine, Assiut University, Assiut, Egypt
| | - Philip Meuleman
- Laboratory of Liver Infectious Diseases, Department of Diagnostic Sciences, Faculty of Medicine and Health Sciences, Ghent University, Ghent, Belgium
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Choe S, Song S, Park GN, Shin J, Kim KS, Cha RM, Hyun BH, Park BK, An DJ. Detection of subtypes (3a, 4a and 4d) and high prevalence of hepatitis E virus in Korean wild boar. Vet Microbiol 2019; 240:108531. [PMID: 31902495 DOI: 10.1016/j.vetmic.2019.108531] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2019] [Revised: 11/26/2019] [Accepted: 11/26/2019] [Indexed: 11/15/2022]
Abstract
The hepatitis E virus (HEV) is known to have 4 genotypes but only one serotype. Genotype 1 and 2 infect humans only and genotype 3 and 4 infect humans, pigs and other animal species. Pig and wild boar are also known as reservoirs of HEV infection. Of the 2736 wild boars captured from 2011 to 2016 to investigate the HEV prevalence among Korean wild boars, 1041 serum samples were high seropositive (38.1%; 95% CI: 35.5-40.5) for HEV, which were detected using the anti-HEV antibody ELISA and the highest prevalence rate was 40.6% (684/1683) in 2016. Twenty four HEV strains were also identified from 1859 wild boar bloods captured between 2015 and 2016. The phylogenetic tree constructed based on the partial ORF2 gene revealed that the 23 Korean wild boar HEV strains belonged to genotype 4 (4a and 4d) showing the nucleotide sequences identities 83.4-100 %. The one Korean wild boar HEV strain belonged to genotype 3, segregated into subgenotype 3a. This suggested that major circulating in Korean wild boars is genotype 4a whereas genotype 3a and -4d is minor. It is important to the human public health that HEV with wild boar have potential high risk factor for transmission to human due to eating culture of Korean people with undercooked wild boar gallbladder.
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Affiliation(s)
- SeEun Choe
- Virus Disease Division, Animal and Plant Quarantine Agency, Gimchen, Gyeongbuk-do, 39660, South Korea
| | - Sok Song
- Virus Disease Division, Animal and Plant Quarantine Agency, Gimchen, Gyeongbuk-do, 39660, South Korea
| | - Gyu-Nam Park
- Virus Disease Division, Animal and Plant Quarantine Agency, Gimchen, Gyeongbuk-do, 39660, South Korea
| | - Jihye Shin
- Virus Disease Division, Animal and Plant Quarantine Agency, Gimchen, Gyeongbuk-do, 39660, South Korea
| | - Ki-Sun Kim
- Virus Disease Division, Animal and Plant Quarantine Agency, Gimchen, Gyeongbuk-do, 39660, South Korea
| | - Ra Mi Cha
- Virus Disease Division, Animal and Plant Quarantine Agency, Gimchen, Gyeongbuk-do, 39660, South Korea
| | - Bang-Hun Hyun
- Virus Disease Division, Animal and Plant Quarantine Agency, Gimchen, Gyeongbuk-do, 39660, South Korea
| | - Bong-Kyun Park
- Virus Disease Division, Animal and Plant Quarantine Agency, Gimchen, Gyeongbuk-do, 39660, South Korea; College of Veterinary Medicine, Seoul University, Gwanak-ro, Gwanak-gu, Seoul, 08826, South Korea
| | - Dong-Jun An
- Virus Disease Division, Animal and Plant Quarantine Agency, Gimchen, Gyeongbuk-do, 39660, South Korea.
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Hepatitis E virus infections in Europe. J Clin Virol 2019; 120:20-26. [DOI: 10.1016/j.jcv.2019.09.004] [Citation(s) in RCA: 33] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2019] [Accepted: 09/06/2019] [Indexed: 12/11/2022]
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