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Falkenhagen A, Panajotov J, Johne R. Colon-derived Caco-2 cells support replication of hepatitis E virus genotype 1 strain Sar55 generated by reverse genetics. Virus Res 2024; 347:199427. [PMID: 38917940 PMCID: PMC11261143 DOI: 10.1016/j.virusres.2024.199427] [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: 05/02/2024] [Revised: 06/20/2024] [Accepted: 06/22/2024] [Indexed: 06/27/2024]
Abstract
The hepatitis E virus (HEV) is infecting over 20 million people annually with a high morbidity especially in pregnant women and immune-suppressed individuals. While HEV genotype 1 (HEV-1) infects only humans, genotype 3 (HEV-3) is zoonotic and commonly transmitted from infected animals to humans. Whereas a few reverse genetics systems enabling targeted genome manipulations exist for HEV-3, those for HEV-1 are still very limited, mainly because of inefficient cell culture replication. Here, the generation of HEV-1 strain Sar55 and HEV-3 strain 47832mc by transfecting in vitro-transcribed and capped virus genomes into different cell lines was attempted. Culture supernatants of colon-derived colorectal adenocarcinoma cell line Caco-2 contained HEV-1 and HEV-3 capable of infecting Caco-2 cells. Density gradient centrifugation analyses of culture supernatants confirmed that HEV-1 particles were quasi-enveloped in analogy to HEV-3 and that non-virion-associated capsid protein was secreted from cells. Following transfection or infection of Caco-2 cells, HEV-1 consistently reached higher titers than HEV-3 in culture supernatants, but HEV-1 generated by transfection of Caco-2 cells was unable to efficiently infect hepatoma cell lines PLC/PRF/5 or HuH7-Lunet BLR. Taken together, our results indicate that HEV-1 is able to exert a complete replication cycle in Caco-2 cells. An efficient cell culture system for this genotype will be useful for studying species tropism, but further research is required to determine the significance of HEV-1 replication in colon-derived cells.
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Affiliation(s)
- Alexander Falkenhagen
- Department of Biological Safety, German Federal Institute for Risk Assessment, Max-Dohrn-Str. 8-10, 10589 Berlin, Germany.
| | - Jessica Panajotov
- Department of Biological Safety, German Federal Institute for Risk Assessment, Max-Dohrn-Str. 8-10, 10589 Berlin, Germany
| | - Reimar Johne
- Department of Biological Safety, German Federal Institute for Risk Assessment, Max-Dohrn-Str. 8-10, 10589 Berlin, Germany
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2
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Schwickert KK, Glitscher M, Bender D, Benz NI, Murra R, Schwickert K, Pfalzgraf S, Schirmeister T, Hellmich UA, Hildt E. Zika virus replication is impaired by a selective agonist of the TRPML2 ion channel. Antiviral Res 2024; 228:105940. [PMID: 38901736 DOI: 10.1016/j.antiviral.2024.105940] [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: 01/31/2024] [Revised: 05/21/2024] [Accepted: 06/17/2024] [Indexed: 06/22/2024]
Abstract
The flavivirus genus includes human pathogenic viruses such as Dengue (DENV), West Nile (WNV) and Zika virus (ZIKV) posing a global health threat due to limited treatment options. Host ion channels are crucial for various viral life cycle stages, but their potential as targets for antivirals is often not fully realized due to the lack of selective modulators. Here, we observe that treatment with ML2-SA1, an agonist for the human endolysosomal cation channel TRPML2, impairs ZIKV replication. Upon ML2-SA1 treatment, levels of intracellular genomes and number of released virus particles of two different ZIKV isolates were significantly reduced and cells displayed enlarged vesicular structures and multivesicular bodies with ZIKV envelope protein accumulation. However, no increased ZIKV degradation in lysosomal compartments was observed. Rather, the antiviral effect of ML2-SA1 seemed to manifest by the compound's negative impact on genome replication. Moreover, ML2-SA1 treatment also led to intracellular cholesterol accumulation. ZIKV and many other viruses including the Orthohepevirus Hepatitis E virus (HEV) rely on the endolysosomal system and are affected by intracellular cholesterol levels to complete their life cycle. Since we observed that ML2-SA1 also negatively impacted HEV infections in vitro, this compound may harbor a broader antiviral potential through perturbing the intracellular cholesterol distribution. Besides indicating that TRPML2 may be a promising target for combatting viral infections, we uncover a tentative connection between this protein and cholesterol distribution within the context of infectious diseases.
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Affiliation(s)
- Kerstin K Schwickert
- Faculty of Chemistry and Earth Sciences, Institute of Organic Chemistry and Macromolecular Chemistry, Friedrich Schiller University, Jena, Germany; Department of Virology, Paul-Ehrlich-Institut, 63225, Langen, Germany; Department of Chemistry, Johannes Gutenberg-University, 55122, Mainz, Germany
| | - Mirco Glitscher
- Department of Virology, Paul-Ehrlich-Institut, 63225, Langen, Germany
| | - Daniela Bender
- Department of Virology, Paul-Ehrlich-Institut, 63225, Langen, Germany
| | - Nuka Ivalu Benz
- Department of Virology, Paul-Ehrlich-Institut, 63225, Langen, Germany
| | - Robin Murra
- Department of Virology, Paul-Ehrlich-Institut, 63225, Langen, Germany
| | - Kevin Schwickert
- Institute of Pharmaceutical and Biomedical Sciences, Johannes Gutenberg-University, 55122, Mainz, Germany
| | - Steffen Pfalzgraf
- Department of Virology, Paul-Ehrlich-Institut, 63225, Langen, Germany
| | - Tanja Schirmeister
- Institute of Pharmaceutical and Biomedical Sciences, Johannes Gutenberg-University, 55122, Mainz, Germany
| | - Ute A Hellmich
- Faculty of Chemistry and Earth Sciences, Institute of Organic Chemistry and Macromolecular Chemistry, Friedrich Schiller University, Jena, Germany; Centre for Biomolecular Magnetic Resonance (BMRZ), Goethe University, Frankfurt, Germany; Cluster of Excellence "Balance of the Microverse", Friedrich Schiller University, Jena, Germany.
| | - Eberhard Hildt
- Department of Virology, Paul-Ehrlich-Institut, 63225, Langen, Germany.
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Woytinek K, Glitscher M, Hildt E. Antagonism of epidermal growth factor receptor signaling favors hepatitis E virus life cycle. J Virol 2024; 98:e0058024. [PMID: 38856640 PMCID: PMC11265270 DOI: 10.1128/jvi.00580-24] [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: 04/24/2024] [Accepted: 05/09/2024] [Indexed: 06/11/2024] Open
Abstract
Hepatitis E virus (HEV) poses a global threat, which currently remains understudied in terms of host interactions. Epidermal growth factor receptor (EGFR) plays multifaceted roles in viral pathogenesis, impacting host-cell entry, viral replication, and host-defense modulation. On the one hand, EGFR signaling emerged as a major driver in innate immunity; on the other hand, a crosstalk between HEV and EGFR requires deeper analysis. We therefore aimed to dissect the receptor's involvement in the HEV life cycle. In persistently HEV-infected cells, the EGFR amount is decreased alongside with enhanced receptor internalization. As compared with the control ligand-induced EGFR, activation revealed an early receptor internalization and degradation in HEV-replicating cells, resulting in a notable EGFR signaling delay. Interestingly, inhibition or silencing of EGFR increased viral replication, extracellular and intracellular viral transcripts, and released infectious particles. The pro-viral impact of EGFR inhibition was attributed to (i) impaired expression of interferon-stimulated genes, (ii) activation of the autophagosomal system, (iii) virus-induced inhibition of lysosomal acidification, and (iv) a decrease of the cellular cholesterol level. IMPORTANCE This study identifies epidermal growth factor receptor (EGFR) as a novel host factor affecting hepatitis E virus (HEV): EGFR downregulation promotes viral replication, release, and evasion from the innate immune response. The discovery that EGFR inhibition favors viral spread is particularly concerning for HEV patients undergoing EGFR inhibitor treatment.
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Affiliation(s)
| | - Mirco Glitscher
- Division of Virology, Paul Ehrlich Institute, Langen, Germany
| | - Eberhard Hildt
- Division of Virology, Paul Ehrlich Institute, Langen, Germany
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4
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Jung S, Yeo D, Seo DJ, Choi IS, Choi C. Cross-species transmission and histopathological variation in specific-pathogen-free minipigs infected with different hepatitis E virus strains. Vet Res 2024; 55:87. [PMID: 38982477 PMCID: PMC11234777 DOI: 10.1186/s13567-024-01337-3] [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: 02/15/2024] [Accepted: 04/25/2024] [Indexed: 07/11/2024] Open
Abstract
Hepatitis E virus (HEV) is a major cause of viral hepatitis worldwide. Pigs are the natural host of HEV genotype 3 and the main reservoir of HEV. As the host range of HEV genotype 3 expands, the possibility that HEV from various species can be transmitted to humans via pigs is increasing. We investigated the potential cross-species transmission of HEV by infecting minipigs with swine HEV (swHEV), rabbit HEV (rbHEV), and human HEV (huHEV) and examining their histopathological characteristics and distribution in various organs. Fifteen specific-pathogen-free Yucatan minipigs were infected with swHEV, rbHEV, huHEV, or a mock control. In the present study, we analysed faecal shedding, viremia, and serological parameters over a seven-week period. Our results indicated that swHEV exhibited more robust shedding and viremia than non-swHEVs. Only swHEV affected the serological parameters, suggesting strain-specific differences. Histopathological examination revealed distinct patterns in the liver, pancreas, intestine, and lymphoid tissues after infection with each HEV strain. Notably, all three HEVs induced histopathological changes in the pancreas, supporting the association of HEVs with acute pancreatitis. Our results also identified skeletal muscle as a site of HEV antigen presence, suggesting a potential link to myositis. In conclusion, this study provides valuable insights into the infection dynamics of different HEV strains in minipigs, emphasizing the strain-specific variations in virological, serological, and histological parameters. The observed differences in infection kinetics and tissue tropism will contribute to our understanding of HEV pathogenesis and the potential for cross-species transmission.
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Affiliation(s)
- Soontag Jung
- Department of Food and Nutrition, College of Biotechnology and Natural Resources, Chung-Ang University, Anseong, Gyeonggi-Do, 17546, Republic of Korea
- Developmental and Reproductive Toxicology Research Group, Korea Institute of Toxicology, Deajeon, 34114, Republic of Korea
| | - Daseul Yeo
- Department of Food and Nutrition, College of Biotechnology and Natural Resources, Chung-Ang University, Anseong, Gyeonggi-Do, 17546, Republic of Korea
| | - Dong-Joo Seo
- Department of Food and Nutrition, Gwangju University, Gwangju, 61743, Republic of Korea
| | - In-Soo Choi
- Department of Infectious Diseases, College of Veterinary Medicine, Konkuk University, 120 Neungdong-ro, Seoul, Gwangjin-gu, 05029, Republic of Korea
| | - Changsun Choi
- Department of Food and Nutrition, College of Biotechnology and Natural Resources, Chung-Ang University, Anseong, Gyeonggi-Do, 17546, Republic of Korea.
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Paronetto O, Allioux C, Diméglio C, Lobjois L, Jeanne N, Ranger N, Boineau J, Pucelle M, Demmou S, Abravanel F, Chapuy-Regaud S, Izopet J, Lhomme S. Characterization of virus‒host recombinant variants of the hepatitis E virus. J Virol 2024; 98:e0029524. [PMID: 38712945 PMCID: PMC11237545 DOI: 10.1128/jvi.00295-24] [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: 02/13/2024] [Accepted: 04/09/2024] [Indexed: 05/08/2024] Open
Abstract
Hepatitis E virus is a single-strand, positive-sense RNA virus that can lead to chronic infection in immunocompromised patients. Virus-host recombinant variants (VHRVs) have been described in such patients. These variants integrate part of human genes into the polyproline-rich region that could introduce new post-translational modifications (PTMs), such as ubiquitination. The aim of this study was to characterize the replication capacity of different VHRVs, namely, RNF19A, ZNF787, KIF1B, EEF1A1, RNA18, RPS17, and RPL6. We used a plasmid encoding the Kernow strain, in which the fragment encoding the S17 insertion was deleted (Kernow p6 delS17) or replaced by fragments encoding the different insertions. The HEV RNA concentrations in the supernatants and the HepG2/C3A cell lysates were determined via RT-qPCR. The capsid protein ORF2 was immunostained. The effect of ribavirin was also assessed. The HEV RNA concentrations in the supernatants and the cell lysates were higher for the variants harboring the RNF19A, ZNF787, KIF1B, RPS17, and EEF1A1 insertions than for the Kernow p6 del S17, while it was not with RNA18 or RPL6 fragments. The number of ORF2 foci was higher for RNF19A, ZNF787, KIF1B, and RPS17 than for Kernow p6 del S17. VHRVs with replicative advantages were less sensitive to the antiviral effect of ribavirin. No difference in PTMs was found between VHRVs with a replicative advantage and those without. In conclusion, our study showed that insertions did not systematically confer a replicative advantage in vitro. Further studies are needed to determine the mechanisms underlying the differences in replicative capacity. IMPORTANCE Hepatitis E virus (HEV) is a major cause of viral hepatitis. HEV can lead to chronic infection in immunocompromised patients. Ribavirin treatment is currently used to treat such chronic infections. Recently, seven virus-host recombinant viruses were characterized in immunocompromised patients. These viruses have incorporated a portion of a human gene fragment into their genome. We studied the consequences of these insertions on the replication capacity. We found that these inserted fragments could enhance virus replication for five of the seven recombinant variants. We also showed that the recombinant variants with replicative advantages were less sensitive to ribavirin in vitro. Finally, we found that the mechanisms leading to such a replicative advantage do not seem to rely on the post-translational modifications introduced by the human gene fragment that could have modified the function of the viral protein. The mechanisms involved in improving the replication of such recombinant viruses remain to be explored.
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Affiliation(s)
- Olivia Paronetto
- Institut Toulousain des Maladies Infectieuses et Inflammatoires (Infinity), UMR 5051 (CNRS), UMR 1291 (INSERM), Université Toulouse III-Paul Sabatier, Toulouse, France
| | - Claire Allioux
- Institut Toulousain des Maladies Infectieuses et Inflammatoires (Infinity), UMR 5051 (CNRS), UMR 1291 (INSERM), Université Toulouse III-Paul Sabatier, Toulouse, France
| | - Chloé Diméglio
- Institut Toulousain des Maladies Infectieuses et Inflammatoires (Infinity), UMR 5051 (CNRS), UMR 1291 (INSERM), Université Toulouse III-Paul Sabatier, Toulouse, France
- Laboratoire de Virologie, Hôpital Purpan, CHU Toulouse, Toulouse, France
| | - Lhorane Lobjois
- Institut Toulousain des Maladies Infectieuses et Inflammatoires (Infinity), UMR 5051 (CNRS), UMR 1291 (INSERM), Université Toulouse III-Paul Sabatier, Toulouse, France
| | - Nicolas Jeanne
- Institut Toulousain des Maladies Infectieuses et Inflammatoires (Infinity), UMR 5051 (CNRS), UMR 1291 (INSERM), Université Toulouse III-Paul Sabatier, Toulouse, France
- Laboratoire de Virologie, Hôpital Purpan, CHU Toulouse, Toulouse, France
| | - Noémie Ranger
- Laboratoire de Virologie, Hôpital Purpan, CHU Toulouse, Toulouse, France
| | - Jérôme Boineau
- Laboratoire de Virologie, Hôpital Purpan, CHU Toulouse, Toulouse, France
| | - Mélanie Pucelle
- Laboratoire de Virologie, Hôpital Purpan, CHU Toulouse, Toulouse, France
| | - Sofia Demmou
- Laboratoire de Virologie, Hôpital Purpan, CHU Toulouse, Toulouse, France
| | - Florence Abravanel
- Institut Toulousain des Maladies Infectieuses et Inflammatoires (Infinity), UMR 5051 (CNRS), UMR 1291 (INSERM), Université Toulouse III-Paul Sabatier, Toulouse, France
- Laboratoire de Virologie, Hôpital Purpan, CHU Toulouse, Toulouse, France
| | - Sabine Chapuy-Regaud
- Institut Toulousain des Maladies Infectieuses et Inflammatoires (Infinity), UMR 5051 (CNRS), UMR 1291 (INSERM), Université Toulouse III-Paul Sabatier, Toulouse, France
- Laboratoire de Virologie, Hôpital Purpan, CHU Toulouse, Toulouse, France
| | - Jacques Izopet
- Institut Toulousain des Maladies Infectieuses et Inflammatoires (Infinity), UMR 5051 (CNRS), UMR 1291 (INSERM), Université Toulouse III-Paul Sabatier, Toulouse, France
- Laboratoire de Virologie, Hôpital Purpan, CHU Toulouse, Toulouse, France
| | - Sébastien Lhomme
- Institut Toulousain des Maladies Infectieuses et Inflammatoires (Infinity), UMR 5051 (CNRS), UMR 1291 (INSERM), Université Toulouse III-Paul Sabatier, Toulouse, France
- Laboratoire de Virologie, Hôpital Purpan, CHU Toulouse, Toulouse, France
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Semaan D, O'Connor L, Scobie L. Evaluation of Food Homogenates on Cell Survival In Vitro. FOOD AND ENVIRONMENTAL VIROLOGY 2024; 16:253-260. [PMID: 38499912 PMCID: PMC11186945 DOI: 10.1007/s12560-024-09586-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/05/2022] [Accepted: 01/24/2024] [Indexed: 03/20/2024]
Abstract
A critical review on the approaches to assess the infectivity of the Hepatitis E virus (HEV) in food recommended that a cell culture-based method should be developed. Due to the observations that viral loads in food may be low, it is important to maximise the potential for detection of HEV in a food source in order to fully assess infectivity. To do so, would require minimal processing of any target material. In order to proceed with the development of an infectivity culture method that is simple, robust and reproducible, there are a number of points to address; one being to assess if food homogenates are cytotoxic to HEV susceptible target cells. Food matrices previously shown to have detectable HEV nucleic acid were selected for analysis and assessed for their effect on the percentage survival of three cell lines commonly used for infectivity assays. Target cells used were A549, PLC/PRF/5 and HepG2 cells. The results showed that, as expected, various food homogenates have differing effects on cells in vitro. In this study, the most robust cell line over a time period was the A549 cell line in comparison to HepG2, with PLC/PRF/5 cells being the most sensitive. Overall, this data would suggest that FH can be left in contact with A549 cells for a period of up to 72 h to maximise the potential for testing infection. Using food homogenates directly would negate any concerns over losing virus as a result of any additional processing steps.
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Affiliation(s)
- Dima Semaan
- Department of Biological and Biomedical Sciences, School of Health and Life Sciences, Glasgow Caledonian University, Glasgow, UK
| | - Liam O'Connor
- Department of Biological and Biomedical Sciences, School of Health and Life Sciences, Glasgow Caledonian University, Glasgow, UK
| | - Linda Scobie
- Department of Biological and Biomedical Sciences, School of Health and Life Sciences, Glasgow Caledonian University, Glasgow, UK.
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Lorusso P, Pandiscia A, Manfredi A, Tantillo GM, Terio V. Evaluation of hepatitis E virus RNA persistence in experimentally contaminated cured pork liver sausages. Ital J Food Saf 2024; 13:12286. [PMID: 38846049 PMCID: PMC11154169 DOI: 10.4081/ijfs.2024.12286] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2024] [Accepted: 03/11/2024] [Indexed: 06/09/2024] Open
Abstract
Hepatitis E is a disease sustained by RNA viruses, which have four different genotypes, all of which are responsible for acute forms of hepatitis. Genotypes 1 and 2 infect only humans, causing epidemics mainly transmitted by contaminated water, while geno-types 3 and 4 are zoonotic, and the infection is linked to the consumption of raw or undercooked meat or meat products. Hepatitis E virus (HEV) genotypes 3 and 4 have been detected in domestic Suidae, considered the asymptomatic reservoir of HEV, and in wild animals such as wild boar and deer. Despite scientific studies that have highlighted the presence of HEV in cured meat products, such as pork liver sausages, the viral persistence in the different production steps of curing has not been evaluated. Therefore, this study aimed to evaluate the persistence of HEV genotype 3 during the different curing and storage times of experimentally contaminated pork liver sausages using biomolecular methods. The sausages tested positive at all curing and storage times. This study confirms the potential risk attributed to pork liver sausages in HEV transmission. However, to guarantee an efficient risk assessment, future studies will be performed to correlate the presence of HEV RNA with infectious viral particles.
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Johne R, Scholz J, Falkenhagen A. Heat stability of foodborne viruses - Findings, methodological challenges and current developments. Int J Food Microbiol 2024; 413:110582. [PMID: 38290272 DOI: 10.1016/j.ijfoodmicro.2024.110582] [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: 11/01/2023] [Revised: 01/12/2024] [Accepted: 01/14/2024] [Indexed: 02/01/2024]
Abstract
Heat treatment of food represents an important measure to prevent pathogen transmission. Thus far, evaluation of heat treatment processes is mainly based on data from bacteria. However, foodborne viruses have gained increasing attention during the last decades. Here, the published literature on heat stability and inactivation of human norovirus (NoV), hepatitis A virus (HAV) and hepatitis E virus (HEV) was reviewed. Data for surrogate viruses were not included. As stability assessment for foodborne viruses is often hampered by missing infectivity assays, an overview of applied methods is also presented. For NoV, molecular capsid integrity assays were mainly applied, but data from initial studies utilizing novel intestinal enteroid or zebrafish larvae assays are available now. However, these methods are still limited in applicability and sensitivity. For HAV, sufficient cell culture-based inactivation data are available, but almost exclusively for one single strain, thus limiting interpretation of the data for the wide range of field strains. For HEV, data are now available from studies using pig inoculation or cell culture. The results of the reviewed studies generally indicate that NoV, HAV and HEV possess a high heat stability. Heating at 70-72 °C for 2 min significantly reduces infectious titers, but often does not result in a >4 log10 decrease. However, heat stability greatly varied dependent on virus strain, matrix and heating regime. In addition, the applied method largely influenced the result, e.g. capsid integrity assays tend to result in higher measured stabilities than cell culture approaches. It can be concluded that the investigated foodborne viruses show a high heat stability, but can be inactivated by application of appropriate heating protocols. For HAV, suggestions for safe time/temperature combinations for specific foods can be derived from the published studies, with the limitation that they are mostly based on one strain only. Although significant improvement of infectivity assays for NoV and HEV have been made during the last years, further method development regarding sensitivity, robustness and broader applicability is important to generate more reliable heat inactivation data for these foodborne viruses in future.
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Affiliation(s)
- Reimar Johne
- German Federal Institute for Risk Assessment, Max-Dohrn-Str. 8-10, 10589 Berlin, Germany.
| | - Johannes Scholz
- German Federal Institute for Risk Assessment, Max-Dohrn-Str. 8-10, 10589 Berlin, Germany
| | - Alexander Falkenhagen
- German Federal Institute for Risk Assessment, Max-Dohrn-Str. 8-10, 10589 Berlin, Germany
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9
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Glitscher M, Spannaus IM, Behr F, Murra RO, Woytinek K, Bender D, Hildt E. The Protease Domain in HEV pORF1 Mediates the Replicase's Localization to Multivesicular Bodies and Its Exosomal Release. Cell Mol Gastroenterol Hepatol 2024; 17:589-605. [PMID: 38190941 PMCID: PMC10900777 DOI: 10.1016/j.jcmgh.2024.01.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/25/2023] [Revised: 01/03/2024] [Accepted: 01/03/2024] [Indexed: 01/10/2024]
Abstract
BACKGROUND A peculiar feature of the hepatitis E virus (HEV) is its reliance on the exosomal route for viral release. Genomic replication is mediated via the viral polyprotein pORF1, yet little is known about its subcellular localization. METHODS Subcellular localization of pORF1 and its subdomains, generated and cloned based on a structural prediciton of the viral replicase, was analyzed via confocal laser scanning microscopy. Exosomes released from cells were isolated via ultracentrifugation and analyzed by isopycnic density gradient centrifugation. This was followed by fluorimetry or Western blot analyses or reverse transcriptase-polymerase chain reaction to analyze separated particles in more detail. RESULTS We found pORF1 to be accumulating within the endosomal system, most dominantly to multivesicular bodies (MVBs). Expression of the polyprotein's 7 subdomains revealed that the papain-like cysteine-protease (PCP) is the only domain localizing like the full-length protein. A PCP-deficient pORF1 mutant lost its association to MVBs. Strikingly, both pORF1 and PCP can be released via exosomes. Similarly, genomic RNA still is released via exosomes in the absence of pORF2/3. CONCLUSIONS Taken together, we found that pORF1 localizes to MVBs in a PCP-dependent manner, which is followed by exosomal release. This reveals new aspects of HEV life cycle, because replication and release could be coupled at the endosomal interface. In addition, this may mediate capsid-independent spread or may facilitate the spread of viral infection, because genomes entering the cell during de novo infection readily encounter exosomally transferred pORF1.
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Affiliation(s)
- Mirco Glitscher
- Department of Virology, Paul-Ehrlich-Institute, Langen, Germany
| | | | - Fabiane Behr
- Department of Virology, Paul-Ehrlich-Institute, Langen, Germany
| | | | | | - Daniela Bender
- Department of Virology, Paul-Ehrlich-Institute, Langen, Germany
| | - Eberhard Hildt
- Department of Virology, Paul-Ehrlich-Institute, Langen, Germany.
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10
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Locus T, Lambrecht E, Lamoral S, Willems S, Van Gucht S, Vanwolleghem T, Peeters M. A Multifaceted Approach for Evaluating Hepatitis E Virus Infectivity In Vitro: Cell Culture and Innovative Molecular Methods for Integrity Assessment. Vet Sci 2023; 10:676. [PMID: 38133227 PMCID: PMC10748075 DOI: 10.3390/vetsci10120676] [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: 10/25/2023] [Revised: 11/18/2023] [Accepted: 11/21/2023] [Indexed: 12/23/2023] Open
Abstract
Hepatitis E virus is a prominent cause of viral hepatitis worldwide. In Western countries, most infections are asymptomatic. However, acute self-limiting hepatitis and chronic cases in immunocompromised individuals can occur. Studying HEV is challenging due to its difficulty to grow in cell culture. Consequently, the detection of the virus mainly relies on RT-qPCR, which cannot differentiate between infectious and non-infectious particles. To overcome this problem, methods assessing viral integrity offer a possible solution to differentiate between intact and damaged viruses. This study aims at optimizing existing HEV cell culture models and RT-qPCR-based assays for selectively detecting intact virions to establish a reliable model for assessing HEV infectivity. In conclusion, these newly developed methods hold promise for enhancing food safety by identifying approaches for inactivating HEV in food processing, thereby increasing food safety measures.
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Affiliation(s)
- Tatjana Locus
- Fisheries and Food, Technology and Food Unit, Flemish Research Institute for Agriculture (ILVO), Brusselsesteenweg 370, 9090 Melle, Belgium or (T.L.); (E.L.)
- Sciensano, Infectious Diseases in Humans, Viral Diseases, Engelandstraat 642, 1180 Ukkel, Belgium
- Laboratory of Experimental Medicine and Pediatrics, Viral Hepatitis Research Group, University of Antwerp, Drie Eikenstraat 655, 2650 Edegem, Belgium
| | - Ellen Lambrecht
- Fisheries and Food, Technology and Food Unit, Flemish Research Institute for Agriculture (ILVO), Brusselsesteenweg 370, 9090 Melle, Belgium or (T.L.); (E.L.)
| | - Sophie Lamoral
- Sciensano, Infectious Diseases in Humans, Viral Diseases, Engelandstraat 642, 1180 Ukkel, Belgium
| | - Sjarlotte Willems
- Fisheries and Food, Technology and Food Unit, Flemish Research Institute for Agriculture (ILVO), Brusselsesteenweg 370, 9090 Melle, Belgium or (T.L.); (E.L.)
| | - Steven Van Gucht
- Sciensano, Infectious Diseases in Humans, Viral Diseases, Engelandstraat 642, 1180 Ukkel, Belgium
| | - Thomas Vanwolleghem
- Laboratory of Experimental Medicine and Pediatrics, Viral Hepatitis Research Group, University of Antwerp, Drie Eikenstraat 655, 2650 Edegem, Belgium
| | - Michael Peeters
- Sciensano, Infectious Diseases in Humans, Viral Diseases, Engelandstraat 642, 1180 Ukkel, Belgium
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11
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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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12
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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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13
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Bouchard S, Paniconi T, Jubinville É, Goulet-Beaulieu V, Goetz C, Marchand P, Jean J. Inactivation of foodborne viruses by novel organic peroxyacid-based disinfectants. Front Microbiol 2023; 14:1187142. [PMID: 37250052 PMCID: PMC10213756 DOI: 10.3389/fmicb.2023.1187142] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2023] [Accepted: 04/24/2023] [Indexed: 05/31/2023] Open
Abstract
Viruses are responsible for most enteric foodborne illnesses worldwide. The foods most frequently involved are fresh fruits and vegetables since they undergo little or no processing. Washing with a chemical disinfectant is a convenient way of inactivating viruses on foods. Peracetic acid, widely used as a disinfectant in the food industry, has the drawback of leaving a strong odor and is ineffective alone against some foodborne viruses. In this study, four disinfectants, namely per levulinic acid with or without sodium dodecyl sulfate, peracetic acid and a commercial peracetic acid-based disinfectant were tested on murine norovirus 1 (MNV-1), hepatitis A virus (HAV), and hepatitis E virus (HEV). Disinfectant concentrations were 50, 80, 250, 500, and 1000 mg l-1 and contact times were 0.5, 1, 5, and 10 min. Under these conditions, per levulinic acid supplemented with 1% SDS reduced MNV-1 infectious titer by 3 log cycles vs. 2.24 log cycles by peracetic acid within 0.5 min. On stainless steel at 80 ppm, only peracetic acid produced 3-log reductions within 0.5 min. None of these peroxyacids was able to reduce infectious titers of HAV or HEV by even 2 log cycles at any concentration or time-tested. This study will guide the development of new chemical formulas that will be more effective against major foodborne viruses and will have less impact on food quality and the environment.
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Affiliation(s)
- Simon Bouchard
- Département des Sciences des Aliments, Institut sur la Nutrition et les Aliments Fonctionnels (INAF), Université Laval, Québec, QC, Canada
| | - Teresa Paniconi
- Département des Sciences des Aliments, Institut sur la Nutrition et les Aliments Fonctionnels (INAF), Université Laval, Québec, QC, Canada
| | - Éric Jubinville
- Département des Sciences des Aliments, Institut sur la Nutrition et les Aliments Fonctionnels (INAF), Université Laval, Québec, QC, Canada
| | - Valérie Goulet-Beaulieu
- Département des Sciences des Aliments, Institut sur la Nutrition et les Aliments Fonctionnels (INAF), Université Laval, Québec, QC, Canada
| | - Coralie Goetz
- Département des Sciences des Aliments, Institut sur la Nutrition et les Aliments Fonctionnels (INAF), Université Laval, Québec, QC, Canada
| | | | - Julie Jean
- Département des Sciences des Aliments, Institut sur la Nutrition et les Aliments Fonctionnels (INAF), Université Laval, Québec, QC, Canada
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14
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Biedermann P, Klink P, Nocke MK, Papp CP, Harms D, Kebelmann M, Thürmer A, Choi M, Altmann B, Todt D, Hofmann J, Bock CT. Insertions and deletions in the hypervariable region of the hepatitis E virus genome in individuals with acute and chronic infection. Liver Int 2023; 43:794-804. [PMID: 36617681 DOI: 10.1111/liv.15517] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/16/2022] [Revised: 11/30/2022] [Accepted: 01/04/2023] [Indexed: 01/10/2023]
Abstract
BACKGROUND AND AIMS Hepatitis E virus is a major cause of acute hepatitis worldwide and can progress to chronicity in immunocompromised individuals. Various virus-host recombination events have been reported in the hypervariable region of the hepatitis E virus genome, but the patterns of assembly and selection remain unclear. METHODS To gain further insight into viral evolution, we assessed the presence of low abundance variants in 16 samples from individuals with acute or chronic infection using a targeted next-generation sequencing approach. RESULTS In seven samples, different variants with insertions and/or deletions were identified. Among them, eight insertions originating either from human genes or from the hepatitis E virus genome. Five different deletions could be identified. The amino acid composition of sequences with insertions showed a higher frequency of lysine and a lower abundance of proline, and additionally acetylation and ubiquitination sites were more frequent than in hepatitis E virus wild-type sequences. CONCLUSIONS These findings suggest that the nucleotide composition of insertions and sites for post-translational modification may contribute to recombination events. Although the impact of low-level hepatitis E virus variants is uncertain, our results highlight the importance of a highly sensitive next-generation sequencing approach to capture the full diversity of hypervariable region.
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Affiliation(s)
- Paula Biedermann
- Division of Viral Gastroenteritis and Hepatitis Pathogens and Enteroviruses, Department of Infectious Diseases, Robert Koch Institute, Berlin, Germany
- German Centre for Infection Research, Institute of Virology, Charité-Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin and Humboldt-Universität zu Berlin, Berlin Institute of Health, Berlin, Germany
| | - Patrycja Klink
- Division of Viral Gastroenteritis and Hepatitis Pathogens and Enteroviruses, Department of Infectious Diseases, Robert Koch Institute, Berlin, Germany
| | - Maximilian K Nocke
- Department of Molecular and Medical Virology, Ruhr University Bochum, Bochum, Germany
| | - Christian-Patrick Papp
- Division of Viral Gastroenteritis and Hepatitis Pathogens and Enteroviruses, Department of Infectious Diseases, Robert Koch Institute, Berlin, Germany
- German Centre for Infection Research, Institute of Virology, Charité-Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin and Humboldt-Universität zu Berlin, Berlin Institute of Health, Berlin, Germany
| | - Dominik Harms
- Division of Viral Gastroenteritis and Hepatitis Pathogens and Enteroviruses, Department of Infectious Diseases, Robert Koch Institute, Berlin, Germany
| | - Marianne Kebelmann
- Division of Viral Gastroenteritis and Hepatitis Pathogens and Enteroviruses, Department of Infectious Diseases, Robert Koch Institute, Berlin, Germany
| | - Andrea Thürmer
- Genome Sequencing, Methodology and Research Infrastructure, Robert Koch Institute, Berlin, Germany
| | - Mira Choi
- Department of Nephrology and Intensive Medical Care, Charité Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin and Humboldt-Universität zu Berlin, Berlin, Germany
| | - Britta Altmann
- Division of Viral Gastroenteritis and Hepatitis Pathogens and Enteroviruses, Department of Infectious Diseases, Robert Koch Institute, Berlin, Germany
| | - Daniel Todt
- Department of Molecular and Medical Virology, Ruhr University Bochum, Bochum, Germany
- European Virus Bioinformatics Center (EVBC), Jena, Germany
| | - Jörg Hofmann
- German Centre for Infection Research, Institute of Virology, Charité-Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin and Humboldt-Universität zu Berlin, Berlin Institute of Health, Berlin, Germany
- Labor Berlin, Charité-Vivantes GmbH, Berlin, Germany
| | - Claus-Thomas Bock
- Division of Viral Gastroenteritis and Hepatitis Pathogens and Enteroviruses, Department of Infectious Diseases, Robert Koch Institute, Berlin, Germany
- Institute of Tropical Medicine, University of Tuebingen, Tuebingen, Germany
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15
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Oechslin N, Ankavay M, Moradpour D, Gouttenoire J. Expanding the Hepatitis E Virus Toolbox: Selectable Replicons and Recombinant Reporter Genomes. Viruses 2023; 15:v15040869. [PMID: 37112849 PMCID: PMC10147066 DOI: 10.3390/v15040869] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2023] [Revised: 03/27/2023] [Accepted: 03/28/2023] [Indexed: 03/31/2023] Open
Abstract
Hepatitis E virus (HEV) has received relatively little attention for decades although it is now considered as one of the most frequent causes of acute hepatitis worldwide. Our knowledge of this enterically-transmitted, positive-strand RNA virus and its life cycle remains scarce but research on HEV has gained momentum more recently. Indeed, advances in the molecular virology of hepatitis E, including the establishment of subgenomic replicons and infectious molecular clones, now allow study of the entire viral life cycle and to explore host factors required for productive infection. Here, we provide an overview on currently available systems, with an emphasis on selectable replicons and recombinant reporter genomes. Furthermore, we discuss the challenges in developing new systems which should enable to further investigate this widely distributed and important pathogen.
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16
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LeDesma R, Heller B, Biswas A, Maya S, Gili S, Higgins J, Ploss A. Structural features stabilized by divalent cation coordination within hepatitis E virus ORF1 are critical for viral replication. eLife 2023; 12:e80529. [PMID: 36852909 PMCID: PMC9977285 DOI: 10.7554/elife.80529] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2022] [Accepted: 02/12/2023] [Indexed: 03/01/2023] Open
Abstract
Hepatitis E virus (HEV) is an RNA virus responsible for over 20 million infections annually. HEV's open reading frame (ORF)1 polyprotein is essential for genome replication, though it is unknown how the different subdomains function within a structural context. Our data show that ORF1 operates as a multifunctional protein, which is not subject to proteolytic processing. Supporting this model, scanning mutagenesis performed on the putative papain-like cysteine protease (pPCP) domain revealed six cysteines essential for viral replication. Our data are consistent with their role in divalent metal ion coordination, which governs local and interdomain interactions that are critical for the overall structure of ORF1; furthermore, the 'pPCP' domain can only rescue viral genome replication in trans when expressed in the context of the full-length ORF1 protein but not as an individual subdomain. Taken together, our work provides a comprehensive model of the structure and function of HEV ORF1.
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Affiliation(s)
- Robert LeDesma
- Department of Molecular Biology, Lewis Thomas Laboratory, Princeton UniversityPrincetonUnited States
| | - Brigitte Heller
- Department of Molecular Biology, Lewis Thomas Laboratory, Princeton UniversityPrincetonUnited States
| | - Abhishek Biswas
- Department of Molecular Biology, Lewis Thomas Laboratory, Princeton UniversityPrincetonUnited States
| | - Stephanie Maya
- Department of Molecular Biology, Lewis Thomas Laboratory, Princeton UniversityPrincetonUnited States
| | - Stefania Gili
- Department of Geosciences, Princeton UniversityPrincetonUnited States
| | - John Higgins
- Department of Geosciences, Princeton UniversityPrincetonUnited States
| | - Alexander Ploss
- Department of Molecular Biology, Lewis Thomas Laboratory, Princeton UniversityPrincetonUnited States
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17
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In Vitro Replication of Swine Hepatitis E Virus (HEV): Production of Cell-Adapted Strains. Animals (Basel) 2023; 13:ani13020276. [PMID: 36670816 PMCID: PMC9854997 DOI: 10.3390/ani13020276] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2022] [Revised: 01/09/2023] [Accepted: 01/10/2023] [Indexed: 01/15/2023] Open
Abstract
The hepatitis E caused by the virus HEV of genotypes HEV-3 and HEV-4 is a zoonotic foodborne disease spread worldwide. HEV is currently classified into eight different genotypes (HEV-1-8). Genotypes HEV-3 and HEV-4 are zoonotic and are further divided into subtypes. Most of the information on HEV replication remains unknown due to the lack of an efficient cell cultivation system. Over the last couple of years, several protocols for HEV cultivation have been developed on different cell lines; even if they were troublesome, long, and scarcely reproducible, they offered the opportunity to study the replicative cycle of the virus. In the present study, we aimed to obtain a protocol ready to use viral stock in serum free medium that can be used with reduced time of growth and without any purification steps. The employed method allowed isolation and cell adaptation of four swine HEV-3 strains, belonging to three different subtypes. Phylogenetic analyses conducted on partial genome sequences of in vitro isolated strains did not reveal any insertion in the hypervariable region (HVR) of the genomes. A limited number of mutations was acquired in the genome during the virus growth in the partial sequences of Methyltransferase (Met) and ORF2 coding genes.
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18
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Fieulaine S, Tubiana T, Bressanelli S. De novo modelling of HEV replication polyprotein: Five-domain breakdown and involvement of flexibility in functional regulation. Virology 2023; 578:128-140. [PMID: 36527931 DOI: 10.1016/j.virol.2022.12.002] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2022] [Revised: 12/01/2022] [Accepted: 12/02/2022] [Indexed: 12/14/2022]
Abstract
Hepatitis E virus (HEV), a major cause of acute viral hepatitis, is a single-stranded, positive-sense RNA virus. As such, it encodes a 1700-residue replication polyprotein pORF1 that directs synthesis of new viral RNA in infected cells. Here we report extensive modeling with AlphaFold2 of the full-length pORF1, and its production by in vitro translation. From this, we give a detailed update on the breakdown into domains of HEV pORF1. We also provide evidence that pORF1's N-terminal domain is likely to oligomerize to form a dodecameric pore, homologously to what has been described for Chikungunya virus. Beyond providing accurate folds for its five domains, our work highlights that there is no canonical protease encoded in pORF1 and that flexibility in several functionally important regions rather than proteolytic processing may serve to regulate HEV RNA synthesis.
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Affiliation(s)
- Sonia Fieulaine
- Université Paris-Saclay, CEA, CNRS, Institute for Integrative Biology of the Cell (I2BC), 91198, Gif-sur-Yvette, France.
| | - Thibault Tubiana
- Université Paris-Saclay, CEA, CNRS, Institute for Integrative Biology of the Cell (I2BC), 91198, Gif-sur-Yvette, France.
| | - Stéphane Bressanelli
- Université Paris-Saclay, CEA, CNRS, Institute for Integrative Biology of the Cell (I2BC), 91198, Gif-sur-Yvette, France.
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19
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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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20
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Meister TL, Brüggemann Y, Nocke MK, Ulrich RG, Schuhenn J, Sutter K, Gömer A, Bader V, Winklhofer KF, Broering R, Verhoye L, Meuleman P, Vondran FWR, Camuzet C, Cocquerel L, Todt D, Steinmann E. A ribavirin-induced ORF2 single-nucleotide variant produces defective hepatitis E virus particles with immune decoy function. Proc Natl Acad Sci U S A 2022; 119:e2202653119. [PMID: 35969792 PMCID: PMC9407633 DOI: 10.1073/pnas.2202653119] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2022] [Accepted: 06/23/2022] [Indexed: 11/26/2022] Open
Abstract
Hepatitis E virus (HEV) is the causative agent of hepatitis E in humans and is the leading cause of enterically transmitted viral hepatitis worldwide. Ribavirin (RBV) is currently the only treatment option for many patients; however, cases of treatment failures or posttreatment relapses have been frequently reported. RBV therapy was shown to be associated with an increase in HEV genome heterogeneity and the emergence of distinct HEV variants. In this study, we analyzed the impact of eight patient-derived open reading frame 2 (ORF2) single-nucleotide variants (SNVs), which occurred under RBV treatment, on the replication cycle and pathogenesis of HEV. The parental HEV strain and seven ORF2 variants showed comparable levels of RNA replication in human hepatoma cells and primary human hepatocytes. However, a P79S ORF2 variant demonstrated reduced RNA copy numbers released in the supernatant and an impairment in the production of infectious particles. Biophysical and biochemical characterization revealed that this SNV caused defective, smaller HEV particles with a loss of infectiousness. Furthermore, the P79S variant displayed an altered subcellular distribution of the ORF2 protein and was able to interfere with antibody-mediated neutralization of HEV in a competition assay. In conclusion, an SNV in the HEV ORF2 could be identified that resulted in altered virus particles that were noninfectious in vitro and in vivo, but could potentially serve as immune decoys. These findings provide insights in understanding the biology of circulating HEV variants and may guide development of personalized antiviral strategies in the future.
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Affiliation(s)
- Toni Luise Meister
- Department for Molecular and Medical Virology, Ruhr University Bochum, Bochum, 44801 Germany
| | - Yannick Brüggemann
- Department for Molecular and Medical Virology, Ruhr University Bochum, Bochum, 44801 Germany
| | - Maximilian K. Nocke
- Department for Molecular and Medical Virology, Ruhr University Bochum, Bochum, 44801 Germany
| | - Rainer G. Ulrich
- Institute of Novel and Emerging Infectious Disease, Friedrich-Loeffler-Institut, 17493 Greifswald-Insel Riems, Germany
- German Centre for Infection Research, Partner site Hamburg-Lübeck-Borstel-Riems, 17493 Greifswald-Insel Riems, Germany
| | - Jonas Schuhenn
- University Hospital Essen, Institute for Virology, University Duisburg-Essen, 47057 Essen, Germany
| | - Kathrin Sutter
- University Hospital Essen, Institute for Virology, University Duisburg-Essen, 47057 Essen, Germany
| | - André Gömer
- Department for Molecular and Medical Virology, Ruhr University Bochum, Bochum, 44801 Germany
| | - Verian Bader
- Department of Molecular Cell Biology, Institute of Biochemistry and Pathobiochemistry, Ruhr University Bochum, Bochum, 44801 Germany
- Department of Biochemistry of Neurodegenerative Diseases, Institute of Biochemistry and Pathobiochemistry, Ruhr University Bochum, Bochum, 44801 Germany
| | - Konstanze F. Winklhofer
- Department of Molecular Cell Biology, Institute of Biochemistry and Pathobiochemistry, Ruhr University Bochum, Bochum, 44801 Germany
- Cluster of Excellence RESOLV, 44801 Bochum, Germany
| | - Ruth Broering
- Department of Gastroenterology, Hepatology, and Transplant Medicine, University Hospital Essen, University Duisburg-Essen, 47057 Essen, Germany
| | - Lieven Verhoye
- Faculty of Medicine and Health Sciences, Department of Diagnostic Sciences, Laboratory of Liver Infectious Diseases, Ghent University, B-9000 Ghent, Belgium
| | - Philip Meuleman
- Faculty of Medicine and Health Sciences, Department of Diagnostic Sciences, Laboratory of Liver Infectious Diseases, Ghent University, B-9000 Ghent, Belgium
| | - Florian W. R. Vondran
- Department of General, Visceral, and Transplant Surgery, Hannover Medical School, 30625 Hannover, Germany
- German Centre for Infection Research, Partner site Hannover-Braunschweig, 30625 Hannover, Germany
| | - Charline Camuzet
- Pasteur Institute of Lille, Centre Hospitalier Universitaire Lille, CNRS, INSERM, University of Lille, U1019-UMR 9017-Center for Infection and Immunity of Lille, 59000 Lille, France
| | - Laurence Cocquerel
- Pasteur Institute of Lille, Centre Hospitalier Universitaire Lille, CNRS, INSERM, University of Lille, U1019-UMR 9017-Center for Infection and Immunity of Lille, 59000 Lille, France
| | - Daniel Todt
- Department for Molecular and Medical Virology, Ruhr University Bochum, Bochum, 44801 Germany
- European Virus Bioinformatics Center, 07743 Jena, Germany
| | - Eike Steinmann
- Department for Molecular and Medical Virology, Ruhr University Bochum, Bochum, 44801 Germany
- German Centre for Infection Research, External Partner Site, 44801 Bochum, Germany
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21
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Gremmel N, Keuling O, Becher P, Baechlein C. Isolation of 15 hepatitis E virus strains lacking ORF1 rearrangements from wild boar and pig organ samples and efficient replication in cell culture. Transbound Emerg Dis 2022; 69:e2617-e2628. [PMID: 35678772 DOI: 10.1111/tbed.14608] [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: 03/25/2022] [Revised: 05/03/2022] [Accepted: 05/30/2022] [Indexed: 11/29/2022]
Abstract
As a zoonotic pathogen, the hepatitis E virus (HEV) leads to numerous infections in humans with different clinical manifestations. Especially genotype 3, as causative agent of a foodborne zoonosis, is transmitted to humans by ingestion of undercooked or raw meat containing liver from HEV-infected animals. Although the virus' prevalence and dissemination in hosts like wild boar and pig have been well characterized, HEV is greatly understudied on a molecular level and reliable cell culture models are lacking. For this reason, the present study concentrated on the isolation and subsequent characterization of porcine HEV from tissue samples derived from wild boar and domestic pigs: 222 wild boars hunted in Northern Germany were investigated for the presence of HEV RNA with a detection rate of 5.9%. Three additional HEV-positive wild boar liver samples as well as an HEV-positive spleen and a positive kidney from domestic pigs were included. After inoculation of positive samples onto the human hepatoma cell line PLC/PRF/5, cells were grown for several weeks. Successful isolation was confirmed by RT-qPCR, virus passage, immunofluorescence staining and titration. Overall, 15 strains from a total of 18 RNA-positive organ samples could be obtained and viral loads >109 RNA copies/ml were measured in cell culture supernatants. Accordingly, 83.3% of the HEV RNA-positive samples contained infectious hepatitis E viral particles and therefore must be considered as a potential source for human infections. Phylogenetic analyses revealed that all isolated strains belong to genotype 3. Further genetic characterization showed a high degree of sequence variability, but no sequence insertions, in the hypervariable region within the open reading frame 1.
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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
| | - 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.,Present address: Lower Saxony State Office for Consumer Protection and Food Safety, Food and Veterinary Institute Braunschweig/Hannover, Hannover, Germany
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22
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Wolff A, Günther T, Johne R. Stability of Hepatitis E Virus After Drying on Different Surfaces. FOOD AND ENVIRONMENTAL VIROLOGY 2022; 14:138-148. [PMID: 35084668 PMCID: PMC8793819 DOI: 10.1007/s12560-022-09510-7] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/26/2021] [Accepted: 01/12/2022] [Indexed: 06/02/2023]
Abstract
The hepatitis E virus (HEV) causes acute and chronic hepatitis in humans. The zoonotic HEV genotype 3 is mainly transmitted by consumption of contaminated food produced from infected animals. However, transmission via contaminated surfaces has also to be considered. Here, the genotype 3c strain 47832c was dried on steel, wood, plastics and ceramics, stored at 23 °C or 3 °C for up to 8 weeks and remaining infectivity was titrated on cell culture. During the drying process, only a mean 0.2 log10 decrease of HEV infectivity was observed. At 23 °C, remaining infectious virus was detected until week 4 on most surfaces, but HEV was completely inactivated (> 4 log10 decrease) after 8 weeks. At 3 °C, HEV was detectable up to 8 weeks on most surfaces, with an average 2.3 log10 decrease. HEV showed the highest stability on plastics, which was lower on ceramics and steel, and lowest on wood. The addition of bovine serum albumin mimicking high protein load had only a slight stabilizing effect. In conclusion, HEV shows a high stability against drying and subsequent storage on different surfaces. Strict application of hygienic measures during food production is therefore crucial in order to prevent HEV persistence on surfaces and subsequent cross-contamination.
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Affiliation(s)
- Alexander Wolff
- German Federal Institute for Risk Assessment, Max-Dohrn-Straße 8-10, 10589, Berlin, Germany
| | - Taras Günther
- German Federal Institute for Risk Assessment, Max-Dohrn-Straße 8-10, 10589, Berlin, Germany
| | - Reimar Johne
- German Federal Institute for Risk Assessment, Max-Dohrn-Straße 8-10, 10589, Berlin, Germany.
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23
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Cierniak F, Ulrich RG, Groschup MH, Eiden M. A Modular Hepatitis E Virus Replicon System for Studies on the Role of ORF1-Encoded Polyprotein Domains. Pathogens 2022; 11:pathogens11030355. [PMID: 35335679 PMCID: PMC8948863 DOI: 10.3390/pathogens11030355] [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: 02/04/2022] [Revised: 03/04/2022] [Accepted: 03/13/2022] [Indexed: 12/02/2022] Open
Abstract
Zoonotic hepatitis E virus (HEV) infection is an emerging cause of acute viral hepatitis in developed countries. Known reservoirs of zoonotic genotype 3 (HEV-3) are mainly pigs and wild boar, and to a lesser extent rabbits and deer. Rabbit hepatitis E virus (HEV-3ra) is prevalent in rabbits worldwide and represents a particular risk for zoonotic infection. Current understanding of the molecular mechanisms of HEV pathogenesis is incomplete, particularly due to the limited availability of efficient and reliable cell culture systems. In order to identify genomic regions responsible for HEV propagation in cell culture, we developed a modular chimeric reporter replicon system based on cell culture-adapted (Kernow-C1/p6 and 47832mc) and rabbit-derived HEV strains. Replication in HepG2 cells was monitored on the basis of a Gaussia luciferase reporter gene that was inserted in place of the open reading frame (ORF) 2 of the HEV genome. Luciferase activity of rabbit HEV-derived replicons was significantly lower than that of Kernow-C1/p6 and 47832mc replicons. Serial exchanges of defined ORF1 segments within the Kernow-C1/p6 replicon backbone indicated that HEV replication in HepG2 cells is not determined by a single domain but rather by an interplay of longer segments of the ORF1-derived nonstructural polyprotein. This implies that a specific combination of viral factors is required for efficient HEV propagation in cell culture.
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Affiliation(s)
- Filip Cierniak
- Institute of Novel and Emerging Infectious Diseases (INNT), Friedrich-Loeffler-Institut, 17493 Greifswald-Insel Riems, Germany; (F.C.); (R.G.U.); (M.H.G.)
| | - Rainer G. Ulrich
- Institute of Novel and Emerging Infectious Diseases (INNT), Friedrich-Loeffler-Institut, 17493 Greifswald-Insel Riems, Germany; (F.C.); (R.G.U.); (M.H.G.)
- Partner Site Hamburg-Lübeck-Borstel-Riems, German Centre for Infection Research (DZIF), 17493 Greifswald-Insel Riems, Germany
| | - Martin H. Groschup
- Institute of Novel and Emerging Infectious Diseases (INNT), Friedrich-Loeffler-Institut, 17493 Greifswald-Insel Riems, Germany; (F.C.); (R.G.U.); (M.H.G.)
- Partner Site Hamburg-Lübeck-Borstel-Riems, German Centre for Infection Research (DZIF), 17493 Greifswald-Insel Riems, Germany
| | - Martin Eiden
- Institute of Novel and Emerging Infectious Diseases (INNT), Friedrich-Loeffler-Institut, 17493 Greifswald-Insel Riems, Germany; (F.C.); (R.G.U.); (M.H.G.)
- Correspondence:
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24
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Metzger K, Bentaleb C, Hervouet K, Alexandre V, Montpellier C, Saliou JM, Ferrié M, Camuzet C, Rouillé Y, Lecoeur C, Dubuisson J, Cocquerel L, Aliouat-Denis CM. Processing and Subcellular Localization of the Hepatitis E Virus Replicase: Identification of Candidate Viral Factories. Front Microbiol 2022; 13:828636. [PMID: 35283856 PMCID: PMC8908324 DOI: 10.3389/fmicb.2022.828636] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2021] [Accepted: 02/01/2022] [Indexed: 01/26/2023] Open
Abstract
Hepatitis E virus (HEV) is the major cause of acute hepatitis worldwide. HEV is a positive-sense RNA virus expressing three open reading frames (ORFs). ORF1 encodes the ORF1 non-structural polyprotein, the viral replicase which transcribes the full-length genome and a subgenomic RNA that encodes the structural ORF2 and ORF3 proteins. The present study is focused on the replication step with the aim to determine whether the ORF1 polyprotein is processed during the HEV lifecycle and to identify where the replication takes place inside the host cell. As no commercial antibody recognizes ORF1 in HEV-replicating cells, we aimed at inserting epitope tags within the ORF1 protein without impacting the virus replication efficacy. Two insertion sites located in the hypervariable region were thus selected to tolerate the V5 epitope while preserving HEV replication efficacy. Once integrated into the infectious full-length Kernow C-1 p6 strain, the V5 epitopes did neither impact the replication of genomic nor the production of subgenomic RNA. Also, the V5-tagged viral particles remained as infectious as the wildtype particles to Huh-7.5 cells. Next, the expression pattern of the V5-tagged ORF1 was compared in heterologous expression and replicative HEV systems. A high molecular weight protein (180 kDa) that was expressed in all three systems and that likely corresponds to the unprocessed form of ORF1 was detected up to 25 days after electroporation in the p6 cell culture system. Additionally, less abundant products of lower molecular weights were detected in both in cytoplasmic and nuclear compartments. Concurrently, the V5-tagged ORF1 was localized by confocal microscopy inside the cell nucleus but also as compact perinuclear substructures in which ORF2 and ORF3 proteins were detected. Importantly, using in situ hybridization (RNAScope ®), positive and negative-strand HEV RNAs were localized in the perinuclear substructures of HEV-producing cells. Finally, by simultaneous detection of HEV genomic RNAs and viral proteins in these substructures, we identified candidate HEV factories.
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Affiliation(s)
- Karoline Metzger
- CNRS, INSERM, CHU Lille, Institut Pasteur de Lille, U1019 – UMR 9017 – Center for Infection and Immunity of Lille (CIIL), Université de Lille, Lille, France
| | - Cyrine Bentaleb
- CNRS, INSERM, CHU Lille, Institut Pasteur de Lille, U1019 – UMR 9017 – Center for Infection and Immunity of Lille (CIIL), Université de Lille, Lille, France
| | - Kévin Hervouet
- CNRS, INSERM, CHU Lille, Institut Pasteur de Lille, U1019 – UMR 9017 – Center for Infection and Immunity of Lille (CIIL), Université de Lille, Lille, France
| | - Virginie Alexandre
- CNRS, INSERM, CHU Lille, Institut Pasteur de Lille, U1019 – UMR 9017 – Center for Infection and Immunity of Lille (CIIL), Université de Lille, Lille, France
| | - Claire Montpellier
- CNRS, INSERM, CHU Lille, Institut Pasteur de Lille, U1019 – UMR 9017 – Center for Infection and Immunity of Lille (CIIL), Université de Lille, Lille, France
| | - Jean-Michel Saliou
- CNRS, Inserm, CHU Lille, Institut Pasteur de Lille, UMR2014 – US41 – Plateformes Lilloises de Biologie and Santé (PLBS), Université de Lille, Lille, France
| | - Martin Ferrié
- CNRS, INSERM, CHU Lille, Institut Pasteur de Lille, U1019 – UMR 9017 – Center for Infection and Immunity of Lille (CIIL), Université de Lille, Lille, France
| | - Charline Camuzet
- CNRS, INSERM, CHU Lille, Institut Pasteur de Lille, U1019 – UMR 9017 – Center for Infection and Immunity of Lille (CIIL), Université de Lille, Lille, France
| | - Yves Rouillé
- CNRS, INSERM, CHU Lille, Institut Pasteur de Lille, U1019 – UMR 9017 – Center for Infection and Immunity of Lille (CIIL), Université de Lille, Lille, France
| | - Cécile Lecoeur
- CNRS, INSERM, CHU Lille, Institut Pasteur de Lille, U1019 – UMR 9017 – Center for Infection and Immunity of Lille (CIIL), Université de Lille, Lille, France
| | - Jean Dubuisson
- CNRS, INSERM, CHU Lille, Institut Pasteur de Lille, U1019 – UMR 9017 – Center for Infection and Immunity of Lille (CIIL), Université de Lille, Lille, France
| | - Laurence Cocquerel
- CNRS, INSERM, CHU Lille, Institut Pasteur de Lille, U1019 – UMR 9017 – Center for Infection and Immunity of Lille (CIIL), Université de Lille, Lille, France
| | - Cécile-Marie Aliouat-Denis
- CNRS, INSERM, CHU Lille, Institut Pasteur de Lille, U1019 – UMR 9017 – Center for Infection and Immunity of Lille (CIIL), Université de Lille, Lille, France
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25
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Advanced sequencing approaches detected insertions of viral and human origin in the viral genome of chronic hepatitis E virus patients. Sci Rep 2022; 12:1720. [PMID: 35110582 PMCID: PMC8811047 DOI: 10.1038/s41598-022-05706-w] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2021] [Accepted: 01/17/2022] [Indexed: 12/22/2022] Open
Abstract
The awareness of hepatitis E virus (HEV) increased significantly in the last decade due to its unexpectedly high prevalence in high-income countries. There, infections with HEV-genotype 3 (HEV-3) are predominant which can progress to chronicity in immunocompromised individuals. Persistent infection and antiviral therapy can select HEV-3 variants; however, the spectrum and occurrence of HEV-3 variants is underreported. To gain in-depth insights into the viral population and to perform detailed characterization of viral genomes, we used a new approach combining long-range PCR with next-generation and third-generation sequencing which allowed near full-length sequencing of HEV-3 genomes. Furthermore, we developed a targeted ultra-deep sequencing approach to assess the dynamics of clinically relevant mutations in the RdRp-region and to detect insertions in the HVR-domain in the HEV genomes. Using this new approach, we not only identified several insertions of human (AHNAK, RPL18) and viral origin (RdRp-derived) in the HVR-region isolated from an exemplary sample but detected a variant containing two different insertions simultaneously (AHNAK- and RdRp-derived). This finding is the first HEV-variant recognized as such showing various insertions in the HVR-domain. Thus, this molecular approach will add incrementally to our current knowledge of the HEV-genome organization and pathogenesis in chronic hepatitis E.
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26
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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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27
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Cell Culture Isolation and Whole Genome Characterization of Hepatitis E Virus Strains from Wild Boars in Germany. Microorganisms 2021; 9:microorganisms9112302. [PMID: 34835427 PMCID: PMC8624179 DOI: 10.3390/microorganisms9112302] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2021] [Revised: 11/03/2021] [Accepted: 11/04/2021] [Indexed: 11/16/2022] Open
Abstract
Infection with hepatitis E virus (HEV) can cause acute and chronic hepatitis in humans. The HEV genotype 3 can be zoonotically transmitted from animals to humans, with wild boars representing an important reservoir species. Cell culture isolation of HEV is generally difficult and mainly described for human isolates so far. Here, five sera and five liver samples from HEV-RNA-positive wild boar samples were inoculated onto PLC/PRF/5 cells, incubated for 3 months and thereafter passaged for additional 6 weeks. As demonstrated by RT-qPCR, immunofluorescence and immune electron microscopy, virus was successfully isolated from two liver samples, which originally contained high HEV genome copy numbers. Both isolates showed slower growth than the culture-adapted HEV strain 47832c. In contrast to this strain, the isolated strains had no insertions in their hypervariable genome region. Next generation sequencing using an HEV sequence-enriched library enabled full genome sequencing. Strain Wb108/17 belongs to subtype 3f and strain Wb257/17 to a tentative novel subtype recently described in Italian wild boars. The results indicate that HEV can be successfully isolated in cell culture from wild boar samples containing high HEV genome copy numbers. The isolates may be used further to study the zoonotic potential of wild boar-derived HEV subtypes.
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28
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Yadav KK, Kenney SP. Hepatitis E Virus Immunopathogenesis. Pathogens 2021; 10:pathogens10091180. [PMID: 34578211 PMCID: PMC8465319 DOI: 10.3390/pathogens10091180] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2021] [Revised: 09/05/2021] [Accepted: 09/06/2021] [Indexed: 12/22/2022] Open
Abstract
Hepatitis E virus is an important emerging pathogen producing a lethal impact on the pregnant population and immunocompromised patients. Starting in 1983, it has been described as the cause for acute hepatitis transmitted via the fecal–oral route. However, zoonotic and blood transfusion transmission of HEV have been reported in the past few decades, leading to the detailed research of HEV pathogenesis. The reason behind HEV being highly virulent to the pregnant population particularly during the third trimester, leading to maternal and fetal death, remains unknown. Various host factors (immunological, nutritional, hormonal) and viral factors have been studied to define the key determinants assisting HEV to be virulent in pregnant and immunocompromised patients. Similarly, chronic hepatitis is seen particularly in solid organ transplant patients, resulting in fatal conditions. This review describes recent advances in the immunopathophysiology of HEV infections in general, pregnant, and immunocompromised populations, and further elucidates the in vitro and in vivo models utilized to understand HEV pathogenesis.
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29
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Hartard C, Fenaux H, Gentilhomme A, Murray JM, Akand E, Laugel E, Berger S, Maul A, de Rougemont A, Jeulin H, Remen T, Bensenane M, Bronowicki JP, Gantzer C, Bertrand I, Schvoerer E. Variability in molecular characteristics of Hepatitis E virus quasispecies could modify viral surface properties and transmission. J Viral Hepat 2021; 28:1078-1090. [PMID: 33877740 DOI: 10.1111/jvh.13513] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/06/2021] [Revised: 03/10/2021] [Accepted: 04/04/2021] [Indexed: 12/09/2022]
Abstract
Hepatitis E virus (HEV) usually causes self-limited liver diseases but can also result in severe cases. Genotypes 1 (G1) and 2 circulate in developing countries are human-restricted and waterborne, while zoonotic G3 and G4 circulating in industrialized countries preferentially infect human through consumption of contaminated meat. Our aims were to identify amino acid patterns in HEV variants that could be involved in pathogenicity or in transmission modes, related to their impact on antigenicity and viral surface hydrophobicity. HEV sequences from human (n = 37) and environmental origins (wild boar [n = 3], pig slaughterhouse effluent [n = 6] and urban wastewater [n = 2]) were collected for the characterization of quasispecies using ultra-deep sequencing (ORF2/ORF3 overlap). Predictive and functional assays were carried out to investigate viral particle antigenicity and hydrophobicity. Most quasispecies showed a major variant while a mixture was observed in urban wastewater and in one chronically infected patient. Amino acid signatures were identified, as a rabbit-linked HEV pattern in two infected patients, or the S68L (ORF2) / H81C (ORF3) residue mostly identified in wild boars. By comparison with environmental strains, molecular patterns less likely represented in humans were identified. Patterns impacting viral hydrophobicity and/or antigenicity were also observed, and the higher hydrophobicity of HEV naked particles compared with the enveloped forms was demonstrated. HEV variants isolated from human and environment present molecular patterns that could impact their surface properties as well as their transmission. These molecular patterns may concern only one minor variant of a quasispecies and could emerge under selective pressure.
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Affiliation(s)
- Cédric Hartard
- Laboratoire de Virologie, CHRU de Nancy Brabois, Vandoeuvre-lès-Nancy, France.,Université de Lorraine, CNRS, LCPME, Nancy, France
| | - Honorine Fenaux
- Laboratoire de Virologie, CHRU de Nancy Brabois, Vandoeuvre-lès-Nancy, France.,Université de Lorraine, CNRS, LCPME, Nancy, France
| | - Alexis Gentilhomme
- Laboratoire de Virologie, CHRU de Nancy Brabois, Vandoeuvre-lès-Nancy, France
| | - John M Murray
- School of Mathematics and Statistics, UNSW Sydney, Sydney, NSW, Australia
| | - Elma Akand
- School of Mathematics and Statistics, UNSW Sydney, Sydney, NSW, Australia
| | - Elodie Laugel
- Laboratoire de Virologie, CHRU de Nancy Brabois, Vandoeuvre-lès-Nancy, France.,Université de Lorraine, CNRS, LCPME, Nancy, France
| | - Sibel Berger
- Laboratoire de Virologie, CHRU de Nancy Brabois, Vandoeuvre-lès-Nancy, France
| | - Armand Maul
- LIEC (Laboratoire Interdisciplinaire des Environnements Continentaux), Université de Lorraine, CNRS, Metz, France
| | - Alexis de Rougemont
- CHU de Dijon, Centre national de référence des virus entériques, Dijon, France
| | - Hélène Jeulin
- Laboratoire de Virologie, CHRU de Nancy Brabois, Vandoeuvre-lès-Nancy, France.,Université de Lorraine, CNRS, LCPME, Nancy, France
| | - Thomas Remen
- DRCI, Délégation à la Recherche Clinique et à l'Innovation, Unité de Méthodologie, Data Management et Statistique, CHRU de Nancy Brabois, Vandoeuvre-lès-Nancy, France
| | - Mouni Bensenane
- Service d'hépato-gastro-entérologie, CHRU de Nancy Brabois, Vandoeuvre-lès-Nancy, France
| | - Jean-Pierre Bronowicki
- Service d'hépato-gastro-entérologie, CHRU de Nancy Brabois, Vandoeuvre-lès-Nancy, France
| | | | | | - Evelyne Schvoerer
- Laboratoire de Virologie, CHRU de Nancy Brabois, Vandoeuvre-lès-Nancy, France.,Université de Lorraine, CNRS, LCPME, Nancy, France
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30
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A broadly cross-reactive monoclonal antibody against hepatitis E virus capsid antigen. Appl Microbiol Biotechnol 2021; 105:4957-4973. [PMID: 34129082 PMCID: PMC8236046 DOI: 10.1007/s00253-021-11342-7] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2020] [Revised: 04/28/2021] [Accepted: 05/09/2021] [Indexed: 12/27/2022]
Abstract
Abstract To generate a hepatitis E virus (HEV) genotype 3 (HEV-3)–specific monoclonal antibody (mAb), the Escherichia coli–expressed carboxy-terminal part of its capsid protein was used to immunise BALB/c mice. The immunisation resulted in the induction of HEV-specific antibodies of high titre. The mAb G117-AA4 of IgG1 isotype was obtained showing a strong reactivity with the homologous E. coli, but also yeast-expressed capsid protein of HEV-3. The mAb strongly cross-reacted with ratHEV capsid protein derivatives produced in both expression systems and weaker with an E. coli–expressed batHEV capsid protein fragment. In addition, the mAb reacted with capsid protein derivatives of genotypes HEV-2 and HEV-4 and common vole hepatitis E virus (cvHEV), produced by the cell-free synthesis in Chinese hamster ovary (CHO) and Spodoptera frugiperda (Sf21) cell lysates. Western blot and line blot reactivity of the mAb with capsid protein derivatives of HEV-1 to HEV-4, cvHEV, ratHEV and batHEV suggested a linear epitope. Use of truncated derivatives of ratHEV capsid protein in ELISA, Western blot, and a Pepscan analysis allowed to map the epitope within a partially surface-exposed region with the amino acid sequence LYTSV. The mAb was also shown to bind to human patient–derived HEV-3 from infected cell culture and to hare HEV-3 and camel HEV-7 capsid proteins from transfected cells by immunofluorescence assay. The novel mAb may serve as a useful tool for further investigations on the pathogenesis of HEV infections and might be used for diagnostic purposes. Key points • The antibody showed cross-reactivity with capsid proteins of different hepeviruses. • The linear epitope of the antibody was mapped in a partially surface-exposed region. • The antibody detected native HEV-3 antigen in infected mammalian cells. Supplementary Information The online version contains supplementary material available at 10.1007/s00253-021-11342-7.
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31
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Treagus S, Wright C, Baker-Austin C, Longdon B, Lowther J. The Foodborne Transmission of Hepatitis E Virus to Humans. FOOD AND ENVIRONMENTAL VIROLOGY 2021; 13:127-145. [PMID: 33738770 PMCID: PMC8116281 DOI: 10.1007/s12560-021-09461-5] [Citation(s) in RCA: 33] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/20/2020] [Accepted: 01/16/2021] [Indexed: 05/04/2023]
Abstract
Globally, Hepatitis E virus (HEV) causes over 20 million cases worldwide. HEV is an emerging and endemic pathogen within economically developed countries, chiefly resulting from infections with genotype 3 (G3) HEV. G3 HEV is known to be a zoonotic pathogen, with a broad host range. The primary source of HEV within more economically developed countries is considered to be pigs, and consumption of pork products is a significant risk factor and known transmission route for the virus to humans. However, other foods have also been implicated in the transmission of HEV to humans. This review consolidates the information available regarding transmission of HEV and looks to identify gaps where further research is required to better understand how HEV is transmitted to humans through food.
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Affiliation(s)
- Samantha Treagus
- Biosciences, College of Life and Environmental Sciences, University of Exeter, Penryn Campus, Penryn, Cornwall, UK.
- Centre for Environment Fisheries and Aquaculture Science, Barrack Road, Weymouth, Dorset, DT4 8UB, UK.
| | | | - Craig Baker-Austin
- Centre for Environment Fisheries and Aquaculture Science, Barrack Road, Weymouth, Dorset, DT4 8UB, UK
| | - Ben Longdon
- Biosciences, College of Life and Environmental Sciences, University of Exeter, Penryn Campus, Penryn, Cornwall, UK
| | - James Lowther
- Centre for Environment Fisheries and Aquaculture Science, Barrack Road, Weymouth, Dorset, DT4 8UB, UK
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Scholz J, Falkenhagen A, Johne R. The Translated Amino Acid Sequence of an Insertion in the Hepatitis E Virus Strain 47832c Genome, But Not the RNA Sequence, Is Essential for Efficient Cell Culture Replication. Viruses 2021; 13:v13050762. [PMID: 33926134 PMCID: PMC8145396 DOI: 10.3390/v13050762] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2021] [Revised: 04/14/2021] [Accepted: 04/22/2021] [Indexed: 12/19/2022] Open
Abstract
The hepatitis E virus (HEV) can cause hepatitis E in humans. Recently, the occurrence of HEV strains carrying insertions in their hypervariable genome region has been described in chronically infected patients. The insertions originate from human genes or from the HEV genome itself. Although their distinct functions are largely unknown, an involvement in efficient cell culture replication was shown for some strains. The HEV strain 47832c, originally isolated from a chronically infected transplant patient, carries a bipartite insertion composed of HEV genome duplications. Here, several mutants with deletions and substitutions of the insertion were generated and tested in cell culture. Complete deletion of the insertion abolished virus replication and even a single glycine to arginine substitution led to reduced cell culture growth. A mutant encoding a frameshift of the inserted sequence was not infectious, whereas a mutant carrying synonymous codons in this region replicated similar like the wild type. Substitution of the insertion with the S17 insertion from HEV strain Kernow C1-p6 did not result in viable virus, which might indicate strain- or cell type-specificity of the insertions. Generally, the translated amino acid sequence of the insertion, but not the RNA sequence, seems to be responsible for the observed effect.
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Identification of the interferon-inducible GTPase GBP1 as major restriction factor for the Hepatitis E virus. J Virol 2021; 95:JVI.01564-20. [PMID: 33472929 PMCID: PMC8092694 DOI: 10.1128/jvi.01564-20] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
This study aims to gain deeper insight into HEV-induced innate immunity by characterizing the crosstalk between the virus and the host factor guanylate-binding protein 1 (GBP1). We observe that the amount of GBP1 is elevated upon infection, although number of transcripts is decreased, which is explained by a prolonged protein half-life. Modulation of GBP1 levels via overexpression significantly inhibits the viral life cycle. Use of various GBP-1 mutants revealed that the antiviral effect of GBP-1 on HEV is independent from the GTPase-activity, but depends on the capacity of GBP-1 to form GBP1 homodimers. This connects GBP-1 to the autophagosomal pathway. Indeed, dimerization competent GBP1 targets the viral capsid protein to the lysosomal compartment leading to inactivation of the viral particle. Most importantly, silencing of GBP1 abolishes the antiviral effect of IFNγ on HEV. In IFNγ treated cells the virus is targeted to lysosomal structures and destroyed therein. This process depends in part on GBP1. These observations about the relevance of GBP1 for type II interferon-mediated innate immunity against HEV could be a base for tailoring novel antivirals and improvement of disease management.IMPORTANCE Although HEV represents a worldwide public health problem with 20 million infections and 44.000 death cases per year, there are still no specific antivirals available and many aspects of the viral life cycle are not well understood. Here we identify the guanylate binding protein 1 (GBP1) as a restriction factor affecting life cycle of HEV. Surprisingly, the antiviral effect of GBP1 does not depend on its GTPase function, but on its capacity to homodimerize. We revealed that GBP1 exerts its antiviral activity by targeting HEV to the lysosomal compartment where the virus is inactivated. Most importantly, we observed that the antiviral effect of interferon-γ on HEV strongly depends on GBP1. Our observation that GBP1 impairs HEV and is crucial for the antiviral effect of interferons on HEV extends understanding of host defense-mechanisms. As the interferon-system represents a universal defense-mechanism, our study could help to design novel antivirals targeting.
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Pellerin M, Hirchaud E, Blanchard Y, Pavio N, Doceul V. Characterization of a Cell Culture System of Persistent Hepatitis E Virus Infection in the Human HepaRG Hepatic Cell Line. Viruses 2021; 13:406. [PMID: 33806591 PMCID: PMC8001476 DOI: 10.3390/v13030406] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2020] [Revised: 02/19/2021] [Accepted: 02/26/2021] [Indexed: 12/12/2022] Open
Abstract
Hepatitis E virus (HEV) is considered as an emerging global health problem. In most cases, hepatitis E is a self-limiting disease and the virus is cleared spontaneously without the need of antiviral therapy. However, immunocompromised individuals can develop chronic infection and liver fibrosis that can progress rapidly to cirrhosis and liver failure. The lack of efficient and relevant cell culture system and animal models has limited our understanding of the biology of HEV and the development of effective drugs for chronic cases. In the present study, we developed a model of persistent HEV infection in human hepatocytes in which HEV replicates efficiently. This HEV cell culture system is based on differentiated HepaRG cells infected with an isolate of HEV-3 derived from a patient suffering from acute hepatitis E. Efficient replication was maintained for several weeks to several months as well as after seven successive passages on HepaRG naïve cells. Moreover, after six passages onto HepaRG, we found that the virus was still infectious after oral inoculation into pigs. We also showed that ribavirin had an inhibitory effect on HEV replication in HepaRG. In conclusion, this system represents a relevant and efficient in vitro model of HEV replication that could be useful to study HEV biology and identify effective antiviral drugs against chronic HEV infection.
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Affiliation(s)
- Marie Pellerin
- UMR 1161 Virologie, INRAE, ANSES, Ecole Nationale Vétérinaire d’Alfort, Université Paris-Est, 94700 Maisons-Alfort, France; (M.P.); (N.P.)
| | - Edouard Hirchaud
- Agence Nationale de Sécurité Sanitaire, De L’environnement et du Travail (ANSES), Laboratory of Ploufragan-Plouzané-Niort, Viral Genetic and Biosafety (GVB) Unit, 22440 Ploufragan, France; (E.H.); (Y.B.)
| | - Yannick Blanchard
- Agence Nationale de Sécurité Sanitaire, De L’environnement et du Travail (ANSES), Laboratory of Ploufragan-Plouzané-Niort, Viral Genetic and Biosafety (GVB) Unit, 22440 Ploufragan, France; (E.H.); (Y.B.)
| | - Nicole Pavio
- UMR 1161 Virologie, INRAE, ANSES, Ecole Nationale Vétérinaire d’Alfort, Université Paris-Est, 94700 Maisons-Alfort, France; (M.P.); (N.P.)
| | - Virginie Doceul
- UMR 1161 Virologie, INRAE, ANSES, Ecole Nationale Vétérinaire d’Alfort, Université Paris-Est, 94700 Maisons-Alfort, France; (M.P.); (N.P.)
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Glitscher M, Martín DH, Woytinek K, Schmidt B, Tabari D, Scholl C, Stingl JC, Seelow E, Choi M, Hildt E. Targeting Cholesterol Metabolism as Efficient Antiviral Strategy Against the Hepatitis E Virus. Cell Mol Gastroenterol Hepatol 2021; 12:159-180. [PMID: 33601063 PMCID: PMC8099564 DOI: 10.1016/j.jcmgh.2021.02.002] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/24/2020] [Revised: 02/04/2021] [Accepted: 02/05/2021] [Indexed: 12/12/2022]
Abstract
BACKGROUND AND AIMS The Hepatitis E virus hijacks the endosomal system for its release. These structures are highly dependent on cholesterol. Hence, this study investigates the impact of HEV on cholesterol-metabolism, the effect of intracellular cholesterol content on HEV-release and the potential of cholesterol-modulators to serve as antivirals. METHODS Intracellular cholesterol-content of cells was modulated and impacts on HEV were monitored using qPCR, Western blot, microscopy, virus-titration and density-gradient centrifugation. Blood-lipids and HEV-RNA were routinely quantified in chronically infected patients during follow-up visits. RESULTS In HEV-infected cells, decreased levels of cholesterol are found. In patients, HEV infection decreases serum-lipid concentrations. Importantly, statin treatment herein increases viral titers. Similarly, reduction of intracellular cholesterol via simvastatin treatment increases viral release in vitro. On the contrary, elevating intracellular cholesterol via LDL or 25-hydroxycholesterol strongly reduces viral release due to enhanced lysosomal degradation of HEV. Drug-induced elevation of intracellular cholesterol via fenofibrate or PSC833 impairs HEV release via the same mechanism. CONCLUSIONS This study analyses the crosstalk between HEV and intracellular cholesterol. The results highlight the importance of an intact cholesterol homeostasis for HEV-release and thereby identify a potential target for antiviral strategies. Especially fenofibrate is considered a promising novel antiviral against HEV. Beyond this, the study may help clinicians evaluating co-treatments of HEV-infected patients with statins, as this may be counter indicated.
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Affiliation(s)
| | | | | | | | - Denna Tabari
- Research Division, Federal Institute for Drugs and Medical Devices, Bonn, Germany
| | - Catharina Scholl
- Research Division, Federal Institute for Drugs and Medical Devices, Bonn, Germany
| | - Julia C. Stingl
- Institute of Clinical Pharmacology, University Hospital of RWTH Aachen, Aachen, Germany
| | - Evelyn Seelow
- Department of Nephrology and Medical Intensive Care, Charité Universitätsmedizin Berlin, Berlin, Germany
| | - Mira Choi
- Department of Nephrology and Medical Intensive Care, Charité Universitätsmedizin Berlin, Berlin, Germany
| | - Eberhard Hildt
- Department Virology, Paul-Ehrlich-Institut, Langen, Germany,Correspondence Address requests for correspondence to Eberhard Hildt, Department Virology, Paul-Ehrlich-Institut, Paul-Ehrlich-Strasse 51-59, D-63225 Langen, Germany. fax: +49610377772140.
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Johne R, Wolff A, Gadicherla AK, Filter M, Schlüter O. Stability of hepatitis E virus at high hydrostatic pressure processing. Int J Food Microbiol 2020; 339:109013. [PMID: 33340943 DOI: 10.1016/j.ijfoodmicro.2020.109013] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2020] [Revised: 12/01/2020] [Accepted: 12/02/2020] [Indexed: 01/26/2023]
Abstract
Hepatitis E virus (HEV) is the causative agent of acute and chronic hepatitis in humans. The zoonotic HEV genotype 3 is the main genotype in Europe. The foodborne transmission via consumption of meat and meat products prepared from infected pigs or wild boars is considered the major transmission route of this genotype. High hydrostatic pressure processing (HPP) is a technique, which can be used for inactivation of pathogens in food. Here, preparations of a cell culture-adapted HEV genotype 3 strain in phosphate-buffered saline (PBS) were subjected to HPP and the remaining infectivity was titrated in cell culture by counting fluorescent foci of replicating virus. A gradual decrease in infectivity was found by application of 100 to 600 MPa for 2 min. At 20 °C, infectivity reduction of 0.5 log10 at 200 MPa and 1 log10 at 400 MPa were observed. Slightly higher infectivity reduction of 1 log10 at 200 MPa and 2 log10 at 400 MPa were found by application of the pressure at 4 °C. At both temperatures, the virus was nearly completely inactivated (>3.5 log10 infectivity decrease) at 600 MPa; however, low amounts of remaining infectious virus were observed in one of three replicates in both cases. Transmission electron microscopy showed disassembled and distorted particles in the preparations treated with 600 MPa. Time-course experiments at 400 MPa showed a continuous decline of infectivity from 30 s to 10 min, leading to a 2 log10 infectivity decrease at 20 °C and to a 2.5 log10 infectivity decrease at 4 °C for a 10 min pressure application each. Predictive models for inactivation of HEV by HPP were generated on the basis of the generated data. The results show that HPP treatment can reduce HEV infectivity, which is mainly dependent on pressure height and duration of the HPP treatment. Compared to other viruses, HEV appears to be relatively stable against HPP and high pressure/long time combinations have to be applied for significant reduction of infectivity.
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Affiliation(s)
- R Johne
- German Federal Institute for Risk Assessment, Max-Dohrn-Straße 8-10, 10589 Berlin, Germany.
| | - A Wolff
- German Federal Institute for Risk Assessment, Max-Dohrn-Straße 8-10, 10589 Berlin, Germany
| | - A K Gadicherla
- German Federal Institute for Risk Assessment, Max-Dohrn-Straße 8-10, 10589 Berlin, Germany
| | - M Filter
- German Federal Institute for Risk Assessment, Max-Dohrn-Straße 8-10, 10589 Berlin, Germany
| | - O Schlüter
- Leibniz Institute for Agricultural Engineering and Bioeconomy, Quality and Safety of Food and Feed, Germany
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37
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Chanmanee T, Ajawatanawong P, Louisirirotchanakul S, Chotiyaputta W, Chainuvati S, Wongprompitak P. Phylogenetic analysis of two new complete genomes of the hepatitis E virus (HEV) genotype 3 from Thailand. Mol Biol Rep 2020; 47:8657-8668. [PMID: 33058031 PMCID: PMC7674359 DOI: 10.1007/s11033-020-05908-3] [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: 11/11/2019] [Accepted: 10/08/2020] [Indexed: 02/06/2023]
Abstract
Hepatitis E virus (HEV) is a causative agent of acute viral hepatitis globally. Evolutionary phylogeny classifies the HEV into eight genotypes that correlate with the viral transmission. Only four genotypes have been proven to be responsible for transmission in humans. However, there has been no report on the genomics and genotyping of HEV in Thailand during the past ten years. Here, we identified the genotype distributions of the Thai isolates of HEV and we sequenced two HEV genomes. We screened for 18 Thai isolates of HEV from Siriraj Hospital in Bangkok, from 2014–2016. The HEV genomes were sequenced from the serum and feces of a patient. The results showed that all Thai isolates of HEV were identified as genotype 3 (HEV-3). The ORF2 and genome phylogenies suggested two subgenotypes, called 3.1 and 3.2. The Thai isolates of HEV were frequently found in the subgenotype 3.1. The genome sequences of the two Thai isolates of HEV from the serum and fecal samples of the same patient showed 91% nucleotide similarity with the HEV genotype 3. Comparisons between the HEV genome and the ORF2 phylogenies illustrated that the ORF2 tree can be used to identify HEV genotypes, but it has less phylogenetic power for the HEV evolution. The two new genome sequences of HEV-3 from Thailand could contribute valuable information to the HEV genome study. (226 words)
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Affiliation(s)
- Tipsuda Chanmanee
- Department of Microbiology, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok, Thailand
| | - Pravech Ajawatanawong
- Division of Bioinformatics and Data Management for Research, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok, Thailand
| | - Suda Louisirirotchanakul
- Department of Microbiology, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok, Thailand
| | - Watcharasak Chotiyaputta
- Division of Gastroenterology, Department of Medicine, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok, Thailand
| | - Siwaporn Chainuvati
- Division of Gastroenterology, Department of Medicine, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok, Thailand
| | - Patimaporn Wongprompitak
- Department of Immunology, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok, Thailand.
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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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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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Lhomme S, Migueres M, Abravanel F, Marion O, Kamar N, Izopet J. Hepatitis E Virus: How It Escapes Host Innate Immunity. Vaccines (Basel) 2020; 8:E422. [PMID: 32731452 PMCID: PMC7564545 DOI: 10.3390/vaccines8030422] [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: 07/10/2020] [Revised: 07/23/2020] [Accepted: 07/24/2020] [Indexed: 12/12/2022] Open
Abstract
Hepatitis E virus (HEV) is a leading cause of viral hepatitis in the world. It is usually responsible for acute hepatitis, but can lead to a chronic infection in immunocompromised patients. The host's innate immune response is the first line of defense against a virus infection; there is growing evidence that HEV RNA is recognized by toll-like receptors (TLRs) and retinoic acid-inducible gene I (RIG-I)-like receptors (RLRs), leading to interferon (IFN) production. The IFNs activate interferon-stimulated genes (ISGs) to limit HEV replication and spread. HEV has developed strategies to counteract this antiviral response, by limiting IFN induction and signaling. This review summarizes the advances in our knowledge of intracellular pathogen recognition, interferon and inflammatory response, and the role of virus protein in immune evasion.
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Affiliation(s)
- Sébastien Lhomme
- National Reference Center for Hepatitis E Virus, Toulouse Purpan University Hospital, 31300 Toulouse, France; (M.M.); (F.A.); (J.I.)
- INSERM UMR1043, CNRS UMR5282, Center for Pathophysiology of Toulouse Purpan, 31300 Toulouse, France; (O.M.); (N.K.)
- Université Toulouse III Paul Sabatier, 31330 Toulouse, France
| | - Marion Migueres
- National Reference Center for Hepatitis E Virus, Toulouse Purpan University Hospital, 31300 Toulouse, France; (M.M.); (F.A.); (J.I.)
- INSERM UMR1043, CNRS UMR5282, Center for Pathophysiology of Toulouse Purpan, 31300 Toulouse, France; (O.M.); (N.K.)
- Université Toulouse III Paul Sabatier, 31330 Toulouse, France
| | - Florence Abravanel
- National Reference Center for Hepatitis E Virus, Toulouse Purpan University Hospital, 31300 Toulouse, France; (M.M.); (F.A.); (J.I.)
- INSERM UMR1043, CNRS UMR5282, Center for Pathophysiology of Toulouse Purpan, 31300 Toulouse, France; (O.M.); (N.K.)
- Université Toulouse III Paul Sabatier, 31330 Toulouse, France
| | - Olivier Marion
- INSERM UMR1043, CNRS UMR5282, Center for Pathophysiology of Toulouse Purpan, 31300 Toulouse, France; (O.M.); (N.K.)
- Université Toulouse III Paul Sabatier, 31330 Toulouse, France
- Department of Nephrology and Organs Transplantation, Toulouse Rangueil University Hospital, 31400 Toulouse, France
| | - Nassim Kamar
- INSERM UMR1043, CNRS UMR5282, Center for Pathophysiology of Toulouse Purpan, 31300 Toulouse, France; (O.M.); (N.K.)
- Université Toulouse III Paul Sabatier, 31330 Toulouse, France
- Department of Nephrology and Organs Transplantation, Toulouse Rangueil University Hospital, 31400 Toulouse, France
| | - Jacques Izopet
- National Reference Center for Hepatitis E Virus, Toulouse Purpan University Hospital, 31300 Toulouse, France; (M.M.); (F.A.); (J.I.)
- INSERM UMR1043, CNRS UMR5282, Center for Pathophysiology of Toulouse Purpan, 31300 Toulouse, France; (O.M.); (N.K.)
- Université Toulouse III Paul Sabatier, 31330 Toulouse, France
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Beyer S, Szewzyk R, Gnirss R, Johne R, Selinka HC. Detection and Characterization of Hepatitis E Virus Genotype 3 in Wastewater and Urban Surface Waters in Germany. FOOD AND ENVIRONMENTAL VIROLOGY 2020; 12:137-147. [PMID: 32172512 PMCID: PMC7225198 DOI: 10.1007/s12560-020-09424-2] [Citation(s) in RCA: 27] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/02/2019] [Accepted: 03/04/2020] [Indexed: 05/18/2023]
Abstract
In highly populated areas, environmental surveillance of wastewater and surface waters is a key factor to control the circulation of viruses and risks for public health. Hepatitis E virus (HEV) genotype 3 is considered as an emerging pathogen in industrialized countries. Therefore, this study was carried out to determine the prevalence of HEV in environmental waters in urban and suburban regions in Germany. HEV was monitored in water samples using quantitative RT-PCR (RT-qPCR) and nested RT-PCR without or with virus concentration via polyethylene glycol precipitation or ultracentrifugation. By RT-qPCR, 84-100% of influent samples of wastewater treatment plants were positive for HEV RNA. Genotypes HEV-3c and 3f were identified in wastewater, with HEV-3c being the most prevalent genotype. These data correlate with subtypes identified earlier in patients from the same area. Comparison of wastewater influent and effluent samples revealed a reduction of HEV RNA of about 1 log10 during passage through wastewater treatment plants. In addition, combined sewer overflows (CSOs) after heavy rainfalls were shown to release HEV RNA into surface waters. About 75% of urban river samples taken during these CSO events were positive for HEV RNA by RT-qPCR. In contrast, under normal weather conditions, only around 30% of river samples and 15% of samples from a bathing water located at an urban river were positive for HEV. Median concentrations of HEV RNA of all tested samples at this bathing water were below the limit of detection.
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Affiliation(s)
- Sophia Beyer
- Section II 1.4 Microbiological Risks, German Environment Agency (UBA), Corrensplatz 1, 14195, Berlin, Germany
| | - Regine Szewzyk
- Section II 1.4 Microbiological Risks, German Environment Agency (UBA), Corrensplatz 1, 14195, Berlin, Germany
| | - Regina Gnirss
- Berliner Wasserbetriebe (BWB), Cicerostr. 24, 10709, Berlin, Germany
| | - Reimar Johne
- German Federal Institute for Risk Assessment (BfR), Max-Dohrn-Straße 8-10, 10589, Berlin, Germany
| | - Hans-Christoph Selinka
- Section II 1.4 Microbiological Risks, German Environment Agency (UBA), Corrensplatz 1, 14195, Berlin, Germany.
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42
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Wolff A, Günther T, Albert T, Schilling-Loeffler K, Gadicherla AK, Johne R. Stability of hepatitis E virus at different pH values. Int J Food Microbiol 2020; 325:108625. [PMID: 32361052 DOI: 10.1016/j.ijfoodmicro.2020.108625] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2020] [Revised: 03/26/2020] [Accepted: 03/30/2020] [Indexed: 12/27/2022]
Abstract
Infection with the hepatitis E virus (HEV) can cause acute and chronic hepatitis in humans. The zoonotic HEV genotype 3 is mainly transmitted by consumption of raw and fermented meat products prepared from infected pigs or wild boars. Lowering of pH during fermentation is one of the microbiological hurdles considered to inhibit growth of certain pathogens. However, no data are currently available on pH stability of HEV. As a reliable and reproducible measurement of HEV infectivity in meat products is not established so far, the stability of the cell culture-adapted HEV genotype 3 strain 47832c was analyzed here in phosphate-buffered saline (PBS) at different pH values. Only a minimal decrease of infectivity (up to 0.6 log10 focus forming units) was found after treatment at pH 2 to 9 for 3 h at room temperature. At pH 10, a decrease of about 3 log10 was evident, whereas no remaining virus (>3.5 log10 decrease) was detected at pH 1. The conditions usually achieved during curing of raw sausages were simulated using D/L-lactic acid added to PBS resulting in pH 4.5 to 6.5. After incubation at 4 °C for 7 days at these conditions, no significant differences as compared to a standard PBS solution at pH 7.7 were evident. At room temperature, a 0.8 log10 decrease was found at pH 4.7 after 7 days incubation compared to pH 7.7, but less at the other pH values. In conclusion, only minimal inactivating effects were found at pH conditions commonly occurring during food processing. Therefore, remaining infectious virus might be present in fermented meat products if HEV-contaminated starting material was used. Additional effects of other factors like high salt concentrations and low aw values should be investigated in future studies.
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Affiliation(s)
- A Wolff
- German Federal Institute for Risk Assessment, Department of Biological Safety, Diedersdorfer Weg 1, 12277 Berlin, Germany
| | - T Günther
- German Federal Institute for Risk Assessment, Department of Biological Safety, Diedersdorfer Weg 1, 12277 Berlin, Germany
| | - T Albert
- University of Leipzig, Institute for Food Hygiene, An den Tierkliniken 1, 04103 Leipzig, Germany
| | - K Schilling-Loeffler
- German Federal Institute for Risk Assessment, Department of Biological Safety, Diedersdorfer Weg 1, 12277 Berlin, Germany
| | - A K Gadicherla
- German Federal Institute for Risk Assessment, Department of Biological Safety, Diedersdorfer Weg 1, 12277 Berlin, Germany
| | - R Johne
- German Federal Institute for Risk Assessment, Department of Biological Safety, Diedersdorfer Weg 1, 12277 Berlin, Germany.
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Nasheri N, Doctor T, Chen A, Harlow J, Gill A. Evaluation of High-Pressure Processing in Inactivation of the Hepatitis E Virus. Front Microbiol 2020; 11:461. [PMID: 32265886 PMCID: PMC7105680 DOI: 10.3389/fmicb.2020.00461] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2019] [Accepted: 03/04/2020] [Indexed: 12/15/2022] Open
Abstract
Hepatitis E virus (HEV) causes acute hepatitis with approximately 20 million cases per year globally. Based on genetic diversity, HEV is classified into different genotypes, with genotype 3 (HEV-3) being most prevalent in Europe and North America. The transmission of HEV-3 has been shown to be zoonotic and mainly associated with the consumption of raw or undercooked pork products. Herein, we investigated the efficacy of high-pressure processing (HPP) in inactivation of HEV-3 using a cell culture system. HPP has been indicated as a promising non-thermal pathogen inactivation strategy for treatment of certain high-risk food commodities, without any noticeable changes in their nature. For this purpose, we treated HEV-3 in media with different conditions of HPP: 400 MPa for 1 and 5 min, as well as 600 MPa for 1 and 5 min, at ambient temperature. All four HPP treatments of HEV in media were observed to result in a 2-log reduction in HEV load, as determined by the amounts of extracellular HEV RNA produced at 14-day post-infection, using the A549/D3 cell culture system. However, application of the same treatments to artificially contaminated pork pâté resulted in 0.5 log reduction in viral load. These results indicate that the efficacy of HPP treatment in the inactivation of HEV-3 is matrix-dependent, and independent of maximum pressure between 400 and 600 MPa and hold time between 1 and 5 min. Based on the obtained results, although the HPP treatment of pork pâté reduces the HEV-3 load, it might not be sufficient to fully mitigate the risk.
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Affiliation(s)
- Neda Nasheri
- National Food Virology Reference Centre, Bureau of Microbial Hazards, Food Directorate, Health Canada, Ottawa, ON, Canada
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Grigas J, Simkute E, Simanavicius M, Pautienius A, Streimikyte-Mockeliune Z, Razukevicius D, Stankevicius A. Hepatitis E genotype 3 virus isolate from wild boar is capable of replication in non-human primate and swine kidney cells and mouse neuroblastoma cells. BMC Vet Res 2020; 16:95. [PMID: 32199460 PMCID: PMC7085153 DOI: 10.1186/s12917-020-02315-5] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2019] [Accepted: 03/12/2020] [Indexed: 12/26/2022] Open
Abstract
BACKGROUND Wild boar-derived hepatitis E (HEV) genotype 3 virus has been successfully isolated in cell lines of human origin only. Considering the zoonotic potential and possible extrahepatic localisation of genotype 3 strain, it is important to investigate the viability of cell lines of different animal and tissue origins. Therefore, the objective of the present study was to determine the permissiveness of non-human primate (MARC-145 and Vero) and swine (PK-15) cell lines of kidney origin, and a mouse neuroblastoma (Neuro-2a) cell line for isolation of wild boar-derived HEV genotype 3. RESULTS This study showed that MARC-145, PK-15, Neuro-2a and Vero cell lines were permissive to wild boar-derived HEV genotype 3 subtype 3i harbouring viral genome equivalents of 1.12 × 107 copies/ml, 2.38 × 105 copies/ml, 2.97 × 107 copies/ml and 4.01 × 107 copies/ml after five serial passages respectively. In all permissive cell lines, HEV was continuously recovered from growth medium between five and at least 28 days post-infection. Peak loads of HEV genome equivalents were observed on days 7, 12, 19 and 30 in MARC-145 (2.88 × 107 copies/ml), Vero (4.23 × 106 copies/ml), Neuro-2a (3.15 × 106 copies/ml) and PK-15 (2.24 × 107 copies/ml) cell lines respectively. In addition, successful virus isolation was confirmed by immunofluorescence assay targeting HEV capsid protein and sequencing of HEV isolate retrieved from cell cultures. CONCLUSIONS This study showed that wild boar-derived HEV genotype 3 subtype 3i strain was capable of infecting cell lines of animal origin, including primate and porcine kidney cells (MARC-145, PK-15 and Vero), and mouse neuroblastoma cells (Neuro-2a), supporting the notion of the capacity of HEV genotype 3 to cross the species barrier and extra-hepatic localisation of the virus. These findings warrant further studies of tested cell lines to investigate their capacity as an efficient system for HEV propagation. HEV isolates from other wild animal hosts should be isolated on tested cell lines in order to generate more data on HEV transmission between wild animal populations and their role as sources of human infections.
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Affiliation(s)
- Juozas Grigas
- Faculty of Veterinary Medicine, Laboratory of Immunology, Department of Anatomy and Physiology, Lithuanian University of Health Sciences, Tilzes str. 18, Kaunas, Lithuania.
| | - Evelina Simkute
- Faculty of Veterinary Medicine, Laboratory of Immunology, Department of Anatomy and Physiology, Lithuanian University of Health Sciences, Tilzes str. 18, Kaunas, Lithuania
| | - Martynas Simanavicius
- Vilnius University Life Sciences Centre, Institute of Biotechnology, Sauletekio al. 7, Vilnius, Lithuania
| | - Arnoldas Pautienius
- Faculty of Veterinary Medicine, Laboratory of Immunology, Department of Anatomy and Physiology, Lithuanian University of Health Sciences, Tilzes str. 18, Kaunas, Lithuania.,Faculty of Veterinary Medicine, Institute of Microbiology and Virology, Lithuanian University of Health Sciences, Tilzes str. 18, Kaunas, Lithuania
| | - Zaneta Streimikyte-Mockeliune
- Faculty of Veterinary Medicine, Institute of Microbiology and Virology, Lithuanian University of Health Sciences, Tilzes str. 18, Kaunas, Lithuania
| | - Dainius Razukevicius
- Faculty of Medicine, Lithuanian University of Health Sciences, A. Mickeviciaus str. 9, Kaunas, Lithuania
| | - Arunas Stankevicius
- Faculty of Veterinary Medicine, Laboratory of Immunology, Department of Anatomy and Physiology, Lithuanian University of Health Sciences, Tilzes str. 18, Kaunas, Lithuania
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Scholz J, Bächlein C, Gadicherla AK, Falkenhagen A, Tausch SH, Johne R. Establishment of a Plasmid-Based Reverse Genetics System for the Cell Culture-Adapted Hepatitis E Virus Genotype 3c Strain 47832c. Pathogens 2020; 9:pathogens9030157. [PMID: 32106549 PMCID: PMC7157446 DOI: 10.3390/pathogens9030157] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2020] [Revised: 02/20/2020] [Accepted: 02/21/2020] [Indexed: 12/13/2022] Open
Abstract
The hepatitis E virus (HEV) causes acute and chronic hepatitis in humans. Investigation of HEV replication is hampered by the lack of broadly applicable, efficient cell culture systems and tools for site-directed mutagenesis of HEV. The cell culture-adapted genotype 3c strain 47832c, which represents a typical genotype predominantly detected in Europe, has previously been used for several basic and applied research studies. Here, a plasmid-based reverse genetics system was developed for this strain, which efficiently rescued the infectious virus without the need for in vitro RNA transcription. The cotransfection of T7 RNA polymerase-expressing BSR/T7 cells with one plasmid encoding the full-length viral genome and two helper plasmids encoding vaccinia virus capping enzymes resulted in the production of infectious HEV, which could be serially passaged on A549/D3 cells. The parental and recombinant virus exhibited similar replication kinetics. A single point mutation creating an additional restriction enzyme site could be successfully introduced into the virus genome of progeny virus, indicating that the system is suitable for site-directed mutagenesis. This system is the first plasmid-based HEV reverse genetics system, as well as the first reverse genetics system for HEV genotype 3c, and should therefore be of broad use for basic and applied HEV research.
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Affiliation(s)
- Johannes Scholz
- Department Biological Safety, German Federal Institute for Risk Assessment, Max-Dohrn-Straße 8-10, 10589 Berlin, Germany; (J.S.); (A.K.G.); (A.F.); (S.H.T.)
| | - Christine Bächlein
- Institute of Virology, Department of Infectious Diseases, University of Veterinary Medicine Hannover, Buenteweg 17, 30559 Hannover, Germany;
| | - Ashish K. Gadicherla
- Department Biological Safety, German Federal Institute for Risk Assessment, Max-Dohrn-Straße 8-10, 10589 Berlin, Germany; (J.S.); (A.K.G.); (A.F.); (S.H.T.)
| | - Alexander Falkenhagen
- Department Biological Safety, German Federal Institute for Risk Assessment, Max-Dohrn-Straße 8-10, 10589 Berlin, Germany; (J.S.); (A.K.G.); (A.F.); (S.H.T.)
| | - Simon H. Tausch
- Department Biological Safety, German Federal Institute for Risk Assessment, Max-Dohrn-Straße 8-10, 10589 Berlin, Germany; (J.S.); (A.K.G.); (A.F.); (S.H.T.)
| | - Reimar Johne
- Department Biological Safety, German Federal Institute for Risk Assessment, Max-Dohrn-Straße 8-10, 10589 Berlin, Germany; (J.S.); (A.K.G.); (A.F.); (S.H.T.)
- Correspondence:
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46
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Lhomme S, Nicot F, Jeanne N, Dimeglio C, Roulet A, Lefebvre C, Carcenac R, Manno M, Dubois M, Peron JM, Alric L, Kamar N, Abravanel F, Izopet J. Insertions and Duplications in the Polyproline Region of the Hepatitis E Virus. Front Microbiol 2020; 11:1. [PMID: 32082274 PMCID: PMC7004952 DOI: 10.3389/fmicb.2020.00001] [Citation(s) in RCA: 112] [Impact Index Per Article: 28.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2019] [Accepted: 01/03/2020] [Indexed: 12/27/2022] Open
Abstract
Recombinant strains of hepatitis E virus (HEV) with insertions of human genomic fragments or HEV sequence duplications in the sequence encoding the polyproline region (PPR) were previously described in chronically infected patients. Such genomic rearrangements confer a replicative advantage in vitro but little is known about their frequency, location, or origin. As the sequences of only a few virus genomes are available, we analyzed the complete genomes of 114 HEV genotype 3 strains from immunocompromised (n = 85) and immunocompetent (n = 29) patients using the single molecular real-time sequencing method to determine the frequency, location, and origin of inserted genomic fragments, plus the proportions of variants with genomic rearrangements in each virus quasispecies. We also examined the amino acid compositions and post-translational modifications conferred by these rearrangements by comparing them to sequences without human gene insertions or HEV gene duplications. We found genomic rearrangements in 7/114 (6.1%) complete genome sequences (4 HEV-3f, 1 HEV-3e, 1 HEV-3 h, and 1 HEV-3chi-new), all from immunocompromised patients, and 3/7 were found at the acute phase of infection. Six of the seven patients harbored virus-host recombinant variants, including one patient with two different recombinant variants. We also detected three recombinant variants with genome duplications of the PPR or PPR + X domains in a single patient. All the genomic rearrangements (seven human fragment insertions of varying origins and three HEV genome duplications) occurred in the PPR. The sequences with genomic rearrangements had specific characteristics: increased net load (p < 0.001) and more ubiquitination (p < 0.001), phosphorylation (p < 0.001), and acetylation (p < 0.001) sites. The human fragment insertions and HEV genome duplications had slightly different characteristics. We believe this is the first description of HEV strains with genomic rearrangements in patients at the acute phase of infection; perhaps these strains are directly transmitted. Clearly, genomic rearrangements produce a greater net load with duplications and insertions having different features. Further studies are needed to clarify the mechanisms by which such modifications influence HEV replication.
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Affiliation(s)
- Sébastien Lhomme
- Laboratoire de Virologie, Centre National de Référence du virus de l'hépatite E, Hôpital Purpan, CHU de Toulouse, Toulouse, France.,INSERM, U1043, Toulouse, France.,Université Toulouse III-Paul Sabatier, Toulouse, France
| | - Florence Nicot
- Laboratoire de Virologie, Centre National de Référence du virus de l'hépatite E, Hôpital Purpan, CHU de Toulouse, Toulouse, France
| | - Nicolas Jeanne
- Laboratoire de Virologie, Centre National de Référence du virus de l'hépatite E, Hôpital Purpan, CHU de Toulouse, Toulouse, France
| | - Chloé Dimeglio
- Laboratoire de Virologie, Centre National de Référence du virus de l'hépatite E, Hôpital Purpan, CHU de Toulouse, Toulouse, France
| | - Alain Roulet
- Plateforme Génomique, Centre INRA Occitanie-Toulouse, Castanet-Tolosan, France
| | - Caroline Lefebvre
- Laboratoire de Virologie, Centre National de Référence du virus de l'hépatite E, Hôpital Purpan, CHU de Toulouse, Toulouse, France
| | - Romain Carcenac
- Laboratoire de Virologie, Centre National de Référence du virus de l'hépatite E, Hôpital Purpan, CHU de Toulouse, Toulouse, France
| | - Maxime Manno
- Plateforme Génomique, Centre INRA Occitanie-Toulouse, Castanet-Tolosan, France
| | - Martine Dubois
- Laboratoire de Virologie, Centre National de Référence du virus de l'hépatite E, Hôpital Purpan, CHU de Toulouse, Toulouse, France
| | - Jean-Marie Peron
- Service de Gastroentérologie, Hôpital Purpan, CHU de Toulouse, Toulouse, France
| | - Laurent Alric
- Service de médecine interne, Hôpital Purpan, CHU de Toulouse, Toulouse, France
| | - Nassim Kamar
- INSERM, U1043, Toulouse, France.,Université Toulouse III-Paul Sabatier, Toulouse, France.,Service de néphrologie, Dialyse et Transplantation d'Organe, Hôpital Rangueil, CHU de Toulouse, Toulouse, France
| | - Florence Abravanel
- Laboratoire de Virologie, Centre National de Référence du virus de l'hépatite E, Hôpital Purpan, CHU de Toulouse, Toulouse, France.,INSERM, U1043, Toulouse, France.,Université Toulouse III-Paul Sabatier, Toulouse, France
| | - Jacques Izopet
- Laboratoire de Virologie, Centre National de Référence du virus de l'hépatite E, Hôpital Purpan, CHU de Toulouse, Toulouse, France.,INSERM, U1043, Toulouse, France.,Université Toulouse III-Paul Sabatier, Toulouse, France
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47
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Lhomme S, Marion O, Abravanel F, Izopet J, Kamar N. Clinical Manifestations, Pathogenesis and Treatment of Hepatitis E Virus Infections. J Clin Med 2020; 9:E331. [PMID: 31991629 PMCID: PMC7073673 DOI: 10.3390/jcm9020331] [Citation(s) in RCA: 42] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2019] [Revised: 01/14/2020] [Accepted: 01/22/2020] [Indexed: 02/07/2023] Open
Abstract
Hepatitis E virus (HEV) is the most common cause of acute viral hepatitis throughout the world. Most infections are acute but they can become chronic in immunocompromised patients, such as solid organ transplant patients, patients with hematologic malignancy undergoing chemotherapy and those with a human immunodeficiency virus (HIV) infection. Extra-hepatic manifestations, especially neurological and renal diseases, have also been described. To date, four main genotypes of HEV (HEV1-4) were described. HEV1 and HEV2 only infect humans, while HEV3 and HEV4 can infect both humans and animals, like pigs, wild boar, deer and rabbits. The real epidemiology of HEV has been underestimated because most infections are asymptomatic. This review focuses on the recent advances in our understanding of the pathophysiology of acute HEV infections, including severe hepatitis in patients with pre-existing liver disease and pregnant women. It also examines the mechanisms leading to chronic infection in immunocompromised patients and extra-hepatic manifestations. Acute infections are usually self-limiting and do not require antiviral treatment. Conversely, a chronic HEV infection can be cleared by decreasing the dose of immunosuppressive drugs or by treating with ribavirin for 3 months. Nevertheless, new drugs are needed for those cases in which ribavirin treatment fails.
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Affiliation(s)
- Sébastien Lhomme
- Virology Laboratory, National Reference Center for Hepatitis E Virus, Toulouse Purpan University Hospital, 31300 Toulouse, France; (F.A.); (J.I.)
- INSERM UMR1043, Center for Pathophysiology of Toulouse Purpan, 31300 Toulouse, France;
- Université Toulouse III Paul Sabatier, 31330 Toulouse, France
| | - Olivier Marion
- INSERM UMR1043, Center for Pathophysiology of Toulouse Purpan, 31300 Toulouse, France;
- Université Toulouse III Paul Sabatier, 31330 Toulouse, France
- Department of Nephrology and Organs Transplantation, Toulouse Rangueil University Hospital, 31400 Toulouse, France
| | - Florence Abravanel
- Virology Laboratory, National Reference Center for Hepatitis E Virus, Toulouse Purpan University Hospital, 31300 Toulouse, France; (F.A.); (J.I.)
- INSERM UMR1043, Center for Pathophysiology of Toulouse Purpan, 31300 Toulouse, France;
- Université Toulouse III Paul Sabatier, 31330 Toulouse, France
| | - Jacques Izopet
- Virology Laboratory, National Reference Center for Hepatitis E Virus, Toulouse Purpan University Hospital, 31300 Toulouse, France; (F.A.); (J.I.)
- INSERM UMR1043, Center for Pathophysiology of Toulouse Purpan, 31300 Toulouse, France;
- Université Toulouse III Paul Sabatier, 31330 Toulouse, France
| | - Nassim Kamar
- INSERM UMR1043, Center for Pathophysiology of Toulouse Purpan, 31300 Toulouse, France;
- Université Toulouse III Paul Sabatier, 31330 Toulouse, France
- Department of Nephrology and Organs Transplantation, Toulouse Rangueil University Hospital, 31400 Toulouse, France
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48
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Müller C, Obermann W, Schulte FW, Lange-Grünweller K, Oestereich L, Elgner F, Glitscher M, Hildt E, Singh K, Wendel HG, Hartmann RK, Ziebuhr J, Grünweller A. Comparison of broad-spectrum antiviral activities of the synthetic rocaglate CR-31-B (-) and the eIF4A-inhibitor Silvestrol. Antiviral Res 2020; 175:104706. [PMID: 31931103 PMCID: PMC7114339 DOI: 10.1016/j.antiviral.2020.104706] [Citation(s) in RCA: 27] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2019] [Revised: 01/04/2020] [Accepted: 01/08/2020] [Indexed: 12/22/2022]
Abstract
Rocaglates, a class of natural compounds isolated from plants of the genus Aglaia, are potent inhibitors of translation initiation. They are proposed to form stacking interactions with polypurine sequences in the 5′-untranslated region (UTR) of selected mRNAs, thereby clamping the RNA substrate onto eIF4A and causing inhibition of the translation initiation complex. Since virus replication relies on the host translation machinery, it is not surprising that the rocaglate Silvestrol has broad-spectrum antiviral activity. Unfortunately, synthesis of Silvestrol is sophisticated and time-consuming, thus hampering the prospects for further antiviral drug development. Here, we present the less complex structured synthetic rocaglate CR-31-B (−) as a novel compound with potent broad-spectrum antiviral activity in primary cells and in an ex vivo bronchial epithelial cell system. CR-31-B (−) inhibited the replication of corona-, Zika-, Lassa-, Crimean Congo hemorrhagic fever viruses and, to a lesser extent, hepatitis E virus (HEV) at non-cytotoxic low nanomolar concentrations. Since HEV has a polypurine-free 5′-UTR that folds into a stable hairpin structure, we hypothesized that RNA clamping by Silvestrol and its derivatives may also occur in a polypurine-independent but structure-dependent manner. Interestingly, the HEV 5′-UTR conferred sensitivity towards Silvestrol but not to CR-31-B (−). However, if an exposed polypurine stretch was introduced into the HEV 5′-UTR, CR-31-B (−) became an active inhibitor comparable to Silvestrol. Moreover, thermodynamic destabilization of the HEV 5′-UTR led to reduced translational inhibition by Silvestrol, suggesting differences between rocaglates in their mode of action, most probably by engaging Silvestrol's additional dioxane moiety. The synthetic rocaglate CR-31-B (−) has broad-spectrum antiviral activity comparable to that of Silvestrol. Both compounds show remarkably low cytotoxicity in primary cells. Silvestrol and CR-31-B (−) are highly efficient against HCoV-229E in a primary human bronchial epithelial cell system. Both compounds reduce LASV and CCHFV titers by about 3–4 logs in primary murine hepatocytes. Only Silvestrol with its characteristic dioxane moiety can clamp polypurine-free structured RNAs onto the eIF4A helicase.
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Affiliation(s)
- Christin Müller
- Institut für Medizinische Virologie, Justus-Liebig-Universität Gießen, Schubertstraße 81, 35392, Gießen, Germany; Deutsches Zentrum für Infektionsforschung (DZIF) at the Partner Site Gießen-Marburg-Langen, Germany
| | - Wiebke Obermann
- Institut für Pharmazeutische Chemie, Philipps-Universität Marburg, Marbacher Weg 6, 35032, Marburg, Germany
| | - Falk W Schulte
- Institut für Pharmazeutische Chemie, Philipps-Universität Marburg, Marbacher Weg 6, 35032, Marburg, Germany
| | - Kerstin Lange-Grünweller
- Institut für Pharmazeutische Chemie, Philipps-Universität Marburg, Marbacher Weg 6, 35032, Marburg, Germany
| | - Lisa Oestereich
- Bernhard-Nocht-Institut für Tropenmedizin, Abteilung Virologie, Hamburg, Germany; Deutsches Zentrum für Infektionsforschung (DZIF) at the Partner Site Hamburg, Germany
| | - Fabian Elgner
- Paul-Ehrlich-Institut, Bundesinstitut für Impfstoffe und Biomedizinische Arzneimittel, Abteilung Virologie, Paul-Ehrlich-Straße 51-59, 63225, Langen, Germany
| | - Mirco Glitscher
- Paul-Ehrlich-Institut, Bundesinstitut für Impfstoffe und Biomedizinische Arzneimittel, Abteilung Virologie, Paul-Ehrlich-Straße 51-59, 63225, Langen, Germany
| | - Eberhard Hildt
- Paul-Ehrlich-Institut, Bundesinstitut für Impfstoffe und Biomedizinische Arzneimittel, Abteilung Virologie, Paul-Ehrlich-Straße 51-59, 63225, Langen, Germany
| | - Kamini Singh
- Cancer Biology and Genetics Program, Memorial Sloan Kettering Cancer Center, New York, NY, 10023, USA
| | - Hans-Guido Wendel
- Cancer Biology and Genetics Program, Memorial Sloan Kettering Cancer Center, New York, NY, 10023, USA
| | - Roland K Hartmann
- Institut für Pharmazeutische Chemie, Philipps-Universität Marburg, Marbacher Weg 6, 35032, Marburg, Germany
| | - John Ziebuhr
- Institut für Medizinische Virologie, Justus-Liebig-Universität Gießen, Schubertstraße 81, 35392, Gießen, Germany; Deutsches Zentrum für Infektionsforschung (DZIF) at the Partner Site Gießen-Marburg-Langen, Germany
| | - Arnold Grünweller
- Institut für Pharmazeutische Chemie, Philipps-Universität Marburg, Marbacher Weg 6, 35032, Marburg, Germany.
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49
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Recombinant Hepatitis E Viruses Harboring Tags in the ORF1 Protein. J Virol 2019; 93:JVI.00459-19. [PMID: 31315997 PMCID: PMC6744232 DOI: 10.1128/jvi.00459-19] [Citation(s) in RCA: 33] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2019] [Accepted: 07/09/2019] [Indexed: 12/15/2022] Open
Abstract
Hepatitis E virus (HEV) infection is an important cause of acute hepatitis and may lead to chronic infection in immunocompromised patients. Knowledge of the viral life cycle is incomplete due to the limited availability of functional tools. In particular, low levels of expression of the ORF1 protein or limited sensitivity of currently available antibodies or both limit our understanding of the viral replicase. Here, we report the successful establishment of subgenomic HEV replicons and full-length genomes harboring an epitope tag or a functional reporter in the ORF1 protein. These novel tools should allow further characterization of the HEV replication complex and to improve our understanding of the viral life cycle. Hepatitis E virus (HEV) is one of the most common causes of acute hepatitis and jaundice in the world. Current understanding of the molecular virology and pathogenesis of hepatitis E is incomplete, due particularly to the limited availability of functional tools. Here, we report the development of tagged HEV genomes as a novel tool to investigate the viral life cycle. A selectable subgenomic HEV replicon was subjected to random 15-nucleotide sequence insertion using transposon-based technology. Viable insertions in the open reading frame 1 (ORF1) protein were selected in a hepatoblastoma cell line. Functional insertion sites were identified downstream of the methyltransferase domain, in the hypervariable region (HVR), and between the helicase and RNA-dependent RNA polymerase domains. HEV genomes harboring a hemagglutinin (HA) epitope tag or a small luciferase (NanoLuc) in the HVR were found to be fully functional and to allow the production of infectious virus. NanoLuc allowed quantitative monitoring of HEV infection and replication by luciferase assay. The use of HA-tagged replicons and full-length genomes allowed localization of putative sites of HEV RNA replication by the simultaneous detection of viral RNA by fluorescence in situ hybridization and of ORF1 protein by immunofluorescence. Candidate HEV replication complexes were found in cytoplasmic dot-like structures which partially overlapped ORF2 and ORF3 proteins as well as exosomal markers. Hence, tagged HEV genomes yield new insights into the viral life cycle and should allow further investigation of the structure and composition of the viral replication complex. IMPORTANCE Hepatitis E virus (HEV) infection is an important cause of acute hepatitis and may lead to chronic infection in immunocompromised patients. Knowledge of the viral life cycle is incomplete due to the limited availability of functional tools. In particular, low levels of expression of the ORF1 protein or limited sensitivity of currently available antibodies or both limit our understanding of the viral replicase. Here, we report the successful establishment of subgenomic HEV replicons and full-length genomes harboring an epitope tag or a functional reporter in the ORF1 protein. These novel tools should allow further characterization of the HEV replication complex and to improve our understanding of the viral life cycle.
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Hartard C, Gantzer C, Bronowicki JP, Schvoerer E. Emerging hepatitis E virus compared with hepatitis A virus: A new sanitary challenge. Rev Med Virol 2019; 29:e2078. [PMID: 31456241 DOI: 10.1002/rmv.2078] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2019] [Revised: 07/19/2019] [Accepted: 07/22/2019] [Indexed: 12/21/2022]
Abstract
Hepatitis A (HAV) and E (HEV) viruses are able to cause liver disease in humans. Among the five classical hepatotropic viruses, they are mainly transmitted via the fecal-oral route. Historically, many similarities have thus been described between them according to their incidence and their pathogenicity, especially in countries with poor sanitary conditions. However, recent advances have provided new insights, and the gap is widening between them. Indeed, while HAV infection incidence tends to decrease in developed countries along with public health improvement, HEV is currently considered as an underdiagnosed emerging pathogen. HEV autochthonous infections are increasingly observed and are mainly associated with zoonotic transmissions. Extra hepatic signs resulting in neurological or renal impairments have also been reported for HEV, as well as a chronic carrier state in immunocompromised patients, arguing in favor of differential pathogenesis between those two viruses. Recent molecular tools have allowed studies of viral genome variability and investigation of links between viral plasticity and clinical evolution. The identification of key functional mutations in viral genomes may improve the knowledge of their clinical impact and is analyzed in depth in the present review.
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Affiliation(s)
- Cédric Hartard
- Laboratoire de Virologie, CHRU de Nancy Brabois, Vandœuvre-lès-Nancy, France.,Laboratoire de Chimie Physique et Microbiologie pour les Matériaux et l'Environnement (LCPME), UMR 7564, Vandoeuvre-lès-Nancy, France.,CNRS, LCPME UMR 7564, Nancy, France.,Faculté des Sciences et Technologies, Institut Jean Barriol, Université de Lorraine, Vandœuvre-lès-Nancy, France
| | - Christophe Gantzer
- Laboratoire de Chimie Physique et Microbiologie pour les Matériaux et l'Environnement (LCPME), UMR 7564, Vandoeuvre-lès-Nancy, France.,CNRS, LCPME UMR 7564, Nancy, France.,Faculté des Sciences et Technologies, Institut Jean Barriol, Université de Lorraine, Vandœuvre-lès-Nancy, France
| | | | - Evelyne Schvoerer
- Laboratoire de Virologie, CHRU de Nancy Brabois, Vandœuvre-lès-Nancy, France.,Laboratoire de Chimie Physique et Microbiologie pour les Matériaux et l'Environnement (LCPME), UMR 7564, Vandoeuvre-lès-Nancy, France.,CNRS, LCPME UMR 7564, Nancy, France.,Faculté des Sciences et Technologies, Institut Jean Barriol, Université de Lorraine, Vandœuvre-lès-Nancy, France
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