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Brüggemann Y, Klöhn M, Wedemeyer H, Steinmann E. Hepatitis E virus: from innate sensing to adaptive immune responses. Nat Rev Gastroenterol Hepatol 2024; 21:710-725. [PMID: 39039260 DOI: 10.1038/s41575-024-00950-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 05/29/2024] [Indexed: 07/24/2024]
Abstract
Hepatitis E virus (HEV) infections are a major cause of acute viral hepatitis in humans worldwide. In immunocompetent individuals, the majority of HEV infections remain asymptomatic and lead to spontaneous clearance of the virus, and only a minority of individuals with infection (5-16%) experience symptoms of acute viral hepatitis. However, HEV infections can cause up to 30% mortality in pregnant women, become chronic in immunocompromised patients and cause extrahepatic manifestations. A growing body of evidence suggests that the host immune response to infection with different HEV genotypes is a critical determinant of distinct HEV infection outcomes. In this Review, we summarize key components of the innate and adaptive immune responses to HEV, including the underlying immunological mechanisms of HEV associated with acute and chronic liver failure and interactions between T cell and B cell responses. In addition, we discuss the current status of vaccines against HEV and raise outstanding questions regarding the immune responses induced by HEV and treatment of the disease, highlighting areas for future investigation.
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Affiliation(s)
- Yannick Brüggemann
- Department of Molecular and Medical Virology, Ruhr University Bochum, Bochum, Germany
| | - Mara Klöhn
- Department of Molecular and Medical Virology, Ruhr University Bochum, Bochum, Germany
| | - Heiner Wedemeyer
- Department of Gastroenterology, Hepatology and Endocrinology, Hannover Medical School, Hannover, Germany
- German Center for Infection Research (DZIF), Partner Sites Hannover-Braunschweig, Hannover, Germany
- Cluster of Excellence RESIST (EXC 2155), Hannover Medical School, Hannover, Germany
| | - Eike Steinmann
- Department of Molecular and Medical Virology, Ruhr University Bochum, Bochum, Germany.
- German Center for Infection Research (DZIF), External Partner Site, Bochum, Germany.
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2
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Quirino A, Marascio N, Branda F, Ciccozzi A, Romano C, Locci C, Azzena I, Pascale N, Pavia G, Matera G, Casu M, Sanna D, Giovanetti M, Ceccarelli G, Alaimo di Loro P, Ciccozzi M, Scarpa F, Maruotti A. Viral Hepatitis: Host Immune Interaction, Pathogenesis and New Therapeutic Strategies. Pathogens 2024; 13:766. [PMID: 39338957 PMCID: PMC11435051 DOI: 10.3390/pathogens13090766] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2024] [Revised: 08/30/2024] [Accepted: 09/02/2024] [Indexed: 09/30/2024] Open
Abstract
Viral hepatitis is a major cause of liver illness worldwide. Despite advances in the understanding of these infections, the pathogenesis of hepatitis remains a complex process driven by intricate interactions between hepatitis viruses and host cells at the molecular level. This paper will examine in detail the dynamics of these host-pathogen interactions, highlighting the key mechanisms that regulate virus entry into the hepatocyte, their replication, evasion of immune responses, and induction of hepatocellular damage. The unique strategies employed by different hepatitis viruses, such as hepatitis B, C, D, and E viruses, to exploit metabolic and cell signaling pathways to their advantage will be discussed. At the same time, the innate and adaptive immune responses put in place by the host to counter viral infection will be analyzed. Special attention will be paid to genetic, epigenetic, and environmental factors that modulate individual susceptibility to different forms of viral hepatitis. In addition, this work will highlight the latest findings on the mechanisms of viral persistence leading to the chronic hepatitis state and the potential implications for the development of new therapeutic strategies. Fully understanding the complex host-pathogen interactions in viral hepatitis is crucial to identifying new therapeutic targets, developing more effective approaches for treatment, and shedding light on the mechanisms underlying progression to more advanced stages of liver damage.
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Affiliation(s)
- Angela Quirino
- Unit of Clinical Microbiology, Department of Health Sciences, “Magna Græcia” University of Catanzaro “Renato Dulbecco” Teaching Hospital, 88100 Catanzaro, Italy; (A.Q.); (N.M.); (G.P.); (G.M.)
| | - Nadia Marascio
- Unit of Clinical Microbiology, Department of Health Sciences, “Magna Græcia” University of Catanzaro “Renato Dulbecco” Teaching Hospital, 88100 Catanzaro, Italy; (A.Q.); (N.M.); (G.P.); (G.M.)
| | - Francesco Branda
- Unit of Medical Statistics and Molecular Epidemiology, Università Campus Bio-Medico di Roma, 00128 Rome, Italy; (C.R.); (M.C.)
| | - Alessandra Ciccozzi
- Department of Biomedical Sciences, University of Sassari, 07100 Sassari, Italy; (A.C.); (C.L.); (D.S.); (F.S.)
| | - Chiara Romano
- Unit of Medical Statistics and Molecular Epidemiology, Università Campus Bio-Medico di Roma, 00128 Rome, Italy; (C.R.); (M.C.)
| | - Chiara Locci
- Department of Biomedical Sciences, University of Sassari, 07100 Sassari, Italy; (A.C.); (C.L.); (D.S.); (F.S.)
- Department of Veterinary Medicine, University of Sassari, 07100 Sassari, Italy; (I.A.); (N.P.); (M.C.)
| | - Ilenia Azzena
- Department of Veterinary Medicine, University of Sassari, 07100 Sassari, Italy; (I.A.); (N.P.); (M.C.)
| | - Noemi Pascale
- Department of Veterinary Medicine, University of Sassari, 07100 Sassari, Italy; (I.A.); (N.P.); (M.C.)
- Department of Chemical Physical Mathematical and Natural Sciences, University of Sassari, 07100 Sassari, Italy
| | - Grazia Pavia
- Unit of Clinical Microbiology, Department of Health Sciences, “Magna Græcia” University of Catanzaro “Renato Dulbecco” Teaching Hospital, 88100 Catanzaro, Italy; (A.Q.); (N.M.); (G.P.); (G.M.)
| | - Giovanni Matera
- Unit of Clinical Microbiology, Department of Health Sciences, “Magna Græcia” University of Catanzaro “Renato Dulbecco” Teaching Hospital, 88100 Catanzaro, Italy; (A.Q.); (N.M.); (G.P.); (G.M.)
| | - Marco Casu
- Department of Veterinary Medicine, University of Sassari, 07100 Sassari, Italy; (I.A.); (N.P.); (M.C.)
| | - Daria Sanna
- Department of Biomedical Sciences, University of Sassari, 07100 Sassari, Italy; (A.C.); (C.L.); (D.S.); (F.S.)
| | - Marta Giovanetti
- Department of Sciences and Technologies for Sustainable Development and One Health, Università Campus Bio-Medico di Roma, 00128 Rome, Italy;
- Instituto René Rachou, Fundação Oswaldo Cruz, Belo Horizonte 30190-002, MG, Brazil
- Climate Amplified Diseases and Epidemics (CLIMADE), Brasilia 70070-130, GO, Brazil
| | - Giancarlo Ceccarelli
- Department of Public Health and Infectious Diseases, University Hospital Policlinico Umberto I, Sapienza University of Rome, 00161 Rome, Italy;
| | | | - Massimo Ciccozzi
- Unit of Medical Statistics and Molecular Epidemiology, Università Campus Bio-Medico di Roma, 00128 Rome, Italy; (C.R.); (M.C.)
| | - Fabio Scarpa
- Department of Biomedical Sciences, University of Sassari, 07100 Sassari, Italy; (A.C.); (C.L.); (D.S.); (F.S.)
| | - Antonello Maruotti
- Department GEPLI, Libera Università Maria Ss Assunta, 00193 Rome, Italy;
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Saadat A, Gouttenoire J, Ripellino P, Semela D, Amar S, Frey BM, Fontana S, Mdawar-Bailly E, Moradpour D, Fellay J, Fraga M. Inborn errors of type I interferon immunity in patients with symptomatic acute hepatitis E. Hepatology 2024; 79:1421-1431. [PMID: 38079352 PMCID: PMC11095861 DOI: 10.1097/hep.0000000000000701] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/06/2023] [Accepted: 11/06/2023] [Indexed: 03/13/2024]
Abstract
BACKGROUND AND AIMS The clinical spectrum of human infection by HEV ranges from asymptomatic to severe acute hepatitis. Furthermore, HEV can cause diverse neurological manifestations, especially Parsonage-Turner syndrome. Here, we used a large-scale human genomic approach to search for genetic determinants of severe clinical presentations of HEV infection. APPROACH AND RESULTS We performed whole genome sequencing in 3 groups of study participants with PCR-proven acute HEV infection: (1) 24 patients with symptomatic acute hepatitis E; (2) 12 patients with HEV-associated Parsonage-Turner syndrome; and (3) 16 asymptomatic blood donors (controls). For variant calling and annotation, we used GATK4 best practices followed by Variant Effect Predictor (VEP) and Annovar. For variant classification, we implemented the American College of Medical Genetics and Genomics/Association for Molecular Pathology Bayesian classification framework in R. Variants with a probability of pathogenicity >0.9 were considered damaging. We used all genes with at least 1 damaging variant as input for pathway enrichment analyses.We observed a significant enrichment of type I interferon response pathways in the symptomatic hepatitis group: 10 out of 24 patients carried a damaging variant in one of 9 genes encoding either intracellular viral sensors ( IFIH1 , DDX58 , TLR3 , POLR3B , POLR3C ) or other molecules involved in type I interferon response [interferon regulatory factor 7 ( IRF7 ), MYD88 , OAS3 , GAPDH ]. We did not find any enriched pathway in the Parsonage-Turner syndrome group or in the controls. CONCLUSIONS Our results highlight the essential role of type I interferon in preventing symptomatic acute hepatitis E.
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Affiliation(s)
- Ali Saadat
- School of Life Sciences, Ecole Polytechnique Fédérale de Lausanne, Lausanne, Switzerland
- Swiss Institute of Bioinformatics, Lausanne, Switzerland
| | - Jérôme Gouttenoire
- Division of Gastroenterology and Hepatology, Lausanne University Hospital and University of Lausanne, Lausanne, Switzerland
| | - Paolo Ripellino
- Department of Neurology, Neurocenter of Southern Switzerland, EOC, Lugano, Switzerland
- Faculty of Biomedical Sciences, Università della Svizzera Italiana, Lugano, Switzerland
| | - David Semela
- Division of Gastroenterology and Hepatology, Kantonsspital St. Gallen, St. Gallen, Switzerland
| | - Soraya Amar
- Swiss Transfusion, Swiss Red Cross, Bern, Switzerland
| | - Beat M. Frey
- Blood Transfusion Service SRC, Schlieren/Zurich, Switzerland
| | | | | | - Elise Mdawar-Bailly
- Division of Gastroenterology and Hepatology, Lausanne University Hospital and University of Lausanne, Lausanne, Switzerland
| | - Darius Moradpour
- Division of Gastroenterology and Hepatology, Lausanne University Hospital and University of Lausanne, Lausanne, Switzerland
| | - Jacques Fellay
- School of Life Sciences, Ecole Polytechnique Fédérale de Lausanne, Lausanne, Switzerland
- Swiss Institute of Bioinformatics, Lausanne, Switzerland
- Precision Medicine Unit, Biomedical Data Science Center, Lausanne University Hospital and University of Lausanne, Lausanne, Switzerland
| | - Montserrat Fraga
- Division of Gastroenterology and Hepatology, Lausanne University Hospital and University of Lausanne, Lausanne, Switzerland
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Ralfs P, Holland B, Salinas E, Bremer B, Wang M, Zhu J, Ambardekar C, Blasczyk H, Walker CM, Feng Z, Grakoui A. Soluble ORF2 protein enhances HEV replication and induces long-lasting antibody response and protective immunity in vivo. Hepatology 2023; 78:1867-1881. [PMID: 37185268 PMCID: PMC10603212 DOI: 10.1097/hep.0000000000000421] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/06/2022] [Accepted: 03/30/2023] [Indexed: 05/17/2023]
Abstract
BACKGROUND AND AIMS The HEV is a small positive-sense RNA virus that encodes a cytoplasmic form of the capsid protein (ORF2c), essential for virion structure, and a secreted glycosylated form (ORF2s) that accumulates at high titer in serum and can mask neutralizing epitopes. We explored the contribution of ORF2s to HEV replication and its role in generating antibodies against ORF2 in a nonhuman primate model. APPROACH AND RESULTS We used a recombinant HEV genotype 3 variant that does not express ORF2s due to the introduction of stop codons (ORF2s mut ). Rhesus macaques (RMs) were given intrahepatic injections of infectious wildtype HEV (ORF2s wt ) RNA or a variant lacking ORF2s expression (ORF2s mut ). The replication of the ORF2s mut virus was delayed by ~2 weeks compared with ORF2s wt , and peak titers were nearly tenfold lower. Reversions of the 3 mutations that blocked ORF2s expression were not detected in the ORF2s mut genomes, indicating genetic stability. However, serum antibodies against ORF2 were transiently detected in RMs infected with ORF2s mut , whereas they were long-lasting in RMs infected with ORF2s wt . Moreover, RMs infected with ORF2s mut were more susceptible to reinfection, as evidenced by the viral RNA detected in fecal samples and the expansion of HEV-specific CD8 + T cells. CONCLUSIONS These findings indicate that ORF2s may be dispensable for viral replication in vivo but is required for long-lived antibody-mediated responses that protect against HEV re-exposure.
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Affiliation(s)
- Philipp Ralfs
- Emory University School of Medicine, Emory University, Atlanta, GA 30329
- Emory National Primate Research Center, Atlanta, GA 30329
| | - Brantley Holland
- Emory University School of Medicine, Emory University, Atlanta, GA 30329
- Emory National Primate Research Center, Atlanta, GA 30329
| | - Eduardo Salinas
- Emory University School of Medicine, Emory University, Atlanta, GA 30329
- Emory National Primate Research Center, Atlanta, GA 30329
| | - Bill Bremer
- Abigail Waxner Research Center, Nationwide Children’s Hospital, Columbus, OH 43205
| | - Minghang Wang
- Abigail Waxner Research Center, Nationwide Children’s Hospital, Columbus, OH 43205
| | - Jingting Zhu
- Abigail Waxner Research Center, Nationwide Children’s Hospital, Columbus, OH 43205
| | - Charuta Ambardekar
- Abigail Waxner Research Center, Nationwide Children’s Hospital, Columbus, OH 43205
| | - Heather Blasczyk
- Abigail Waxner Research Center, Nationwide Children’s Hospital, Columbus, OH 43205
| | | | - Zongdi Feng
- Abigail Waxner Research Center, Nationwide Children’s Hospital, Columbus, OH 43205
| | - Arash Grakoui
- Emory University School of Medicine, Emory University, Atlanta, GA 30329
- Emory National Primate Research Center, Atlanta, GA 30329
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Meyer L, Duquénois I, Gellenoncourt S, Pellerin M, Marcadet-Hauss A, Pavio N, Doceul V. Identification of interferon-stimulated genes with modulated expression during hepatitis E virus infection in pig liver tissues and human HepaRG cells. Front Immunol 2023; 14:1291186. [PMID: 38058490 PMCID: PMC10696647 DOI: 10.3389/fimmu.2023.1291186] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2023] [Accepted: 10/31/2023] [Indexed: 12/08/2023] Open
Abstract
Introduction Hepatitis E virus (HEV) is a common cause of enterically transmitted acute hepatitis worldwide. The virus is transmitted by the fecal-oral route via the consumption of contaminated water supplies and is also a zoonotic foodborne pathogen. Swine are the main reservoir of zoonotic HEV. In humans, HEV infection is usually asymptomatic or causes acute hepatitis that is self-limited. However, fulminant hepatic failure and chronic cases of HEV infection can occur in some patients. In contrast, HEV infection in pigs remains asymptomatic, although the virus replicates efficiently, suggesting that swine are able to control the virus pathogenesis. Upon viral infection, IFN is secreted and activates cellular pathways leading to the expression of many IFN-stimulated genes (ISGs). ISGs can restrict the replication of specific viruses and establish an antiviral state within infected and neighboring cells. Methods In this study, we used PCR arrays to determine the expression level of up to 168 ISGs and other IFN-related genes in the liver tissues of pigs infected with zoonotic HEV-3c and HEV-3f and in human bipotent liver HepaRG cells persistently infected with HEV-3f. Results and discussion The expression of 12 and 25 ISGs was found to be up-regulated in infected swine livers and HepaRG cells, respectively. The expression of CXCL10, IFIT2, MX2, OASL and OAS2 was up-regulated in both species. Increased expression of IFI16 mRNA was also found in swine liver tissues. This study contributes to the identification of potential ISGs that could play a role in the control or persistence of HEV infection.
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Affiliation(s)
| | | | | | | | | | | | - Virginie Doceul
- Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE), Agence Nationale de Sécurité Sanitaire de l’Alimentation, de l’Environnement et du Travail (ANSES), École Nationale Vétérinaire d'Alfort (ENVA), UMR Virology, Maisons-Alfort, France
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León-Janampa N, Caballero-Posadas I, Barc C, Darrouzain F, Moreau A, Guinoiseau T, Gatault P, Fleurot I, Riou M, Pinard A, Pezant J, Rossignol C, Gaudy-Graffin C, Brand D, Marlet J. A pig model of chronic hepatitis E displaying persistent viremia and a downregulation of innate immune responses in the liver. Hepatol Commun 2023; 7:e0274. [PMID: 37938097 PMCID: PMC10635601 DOI: 10.1097/hc9.0000000000000274] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/21/2023] [Accepted: 06/27/2023] [Indexed: 11/09/2023] Open
Abstract
BACKGROUND Hepatitis E virus (HEV) is a zoonotic virus transmitted by pig meat and responsible for chronic hepatitis E in immunocompromised patients. It has proved challenging to reproduce this disease in its natural reservoir. We therefore aimed to develop a pig model of chronic hepatitis E to improve the characterization of this disease. METHODS Ten pigs were treated with a tacrolimus-based regimen and intravenously inoculated with HEV. Tacrolimus trough concentration, HEV viremia, viral diversity, innate immune responses, liver histology, clinical disease and biochemical markers were monitored for 11 weeks post-infection (p.i.). RESULTS HEV viremia persisted for 11 weeks p.i. HEV RNA was detected in the liver, small intestine, and colon at necropsy. Histological analysis revealed liver inflammation and fibrosis. Several mutations selected in the HEV genome were associated with compartmentalization in the feces and intestinal tissues, consistent with the hypothesis of extrahepatic replication in the digestive tract. Antiviral responses were characterized by a downregulation of IFN pathways in the liver, despite an upregulation of RIG-I and ISGs in the blood and liver. CONCLUSIONS We developed a pig model of chronic hepatitis E that reproduced the major hallmarks of this disease. This model revealed a compartmentalization of HEV genomes in the digestive tract and a downregulation of innate immune responses in the liver. These original features highlight the relevance of our model for studies of the pathogenesis of chronic hepatitis E and for validating future treatments.
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Affiliation(s)
- Nancy León-Janampa
- INSERM U1259 MAVIVH, Tours University and Tours University Hospital, Tours, France
| | | | - Céline Barc
- UE-1277 Platform for Experimentation on Infectious Diseases, INRAe, Nouzilly, France
| | - François Darrouzain
- Department of Pharmacology and Toxicology, Tours University Hospital, Tours, France
| | - Alain Moreau
- INSERM U1259 MAVIVH, Tours University and Tours University Hospital, Tours, France
| | - Thibault Guinoiseau
- Department of Bacteriology-Virology-Hygiene, Tours University Hospital, Tours, France
| | - Philippe Gatault
- Department of Nephrology and Transplantation, Tours University Hospital, Tours, France
- EA4245, University of Tours, Tours, France
| | | | - Mickaël Riou
- UE-1277 Platform for Experimentation on Infectious Diseases, INRAe, Nouzilly, France
| | - Anne Pinard
- UE-1277 Platform for Experimentation on Infectious Diseases, INRAe, Nouzilly, France
| | - Jérémy Pezant
- UE-1277 Platform for Experimentation on Infectious Diseases, INRAe, Nouzilly, France
| | | | - Catherine Gaudy-Graffin
- INSERM U1259 MAVIVH, Tours University and Tours University Hospital, Tours, France
- Department of Bacteriology-Virology-Hygiene, Tours University Hospital, Tours, France
| | - Denys Brand
- INSERM U1259 MAVIVH, Tours University and Tours University Hospital, Tours, France
- Department of Bacteriology-Virology-Hygiene, Tours University Hospital, Tours, France
| | - Julien Marlet
- INSERM U1259 MAVIVH, Tours University and Tours University Hospital, Tours, France
- Department of Bacteriology-Virology-Hygiene, Tours University Hospital, Tours, France
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Kumar A, Subramani C, Raj S, Ranjith-Kumar CT, Surjit M. Hepatitis E Virus Protease Inhibits the Activity of Eukaryotic Initiation Factor 2-Alpha Kinase 4 and Promotes Virus Survival. J Virol 2023; 97:e0034723. [PMID: 37199644 PMCID: PMC10308950 DOI: 10.1128/jvi.00347-23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2023] [Accepted: 05/02/2023] [Indexed: 05/19/2023] Open
Abstract
Multiple mechanisms exist in a cell to cope with stress. Four independent stress-sensing kinases constitute the integrated stress response machinery of the mammalian cell, and they sense the stress signals and act by phosphorylating the eukaryotic initiation factor 2α (eIF2α) to arrest cellular translation. Eukaryotic initiation factor 2 alpha kinase 4 (eIF2AK4) is one of the four kinases and is activated under conditions of amino acid starvation, UV radiation, or RNA virus infection, resulting in shutdown of global translation. An earlier study in our laboratory constructed the protein interaction network of the hepatitis E virus (HEV) and identified eIF2AK4 as a host interaction partner of the genotype 1 (g1) HEV protease (PCP). Here, we report that PCP's association with the eIF2AK4 results in inhibition of self-association and concomitant loss of kinase activity of eIF2AK4. Site-directed mutagenesis of the 53rd phenylalanine residue of PCP abolishes its interaction with the eIF2AK4. Further, a genetically engineered HEV-expressing F53A mutant PCP shows poor replication efficiency. Collectively, these data identify an additional property of the g1-HEV PCP protein, through which it helps the virus in antagonizing eIF2AK4-mediated phosphorylation of the eIF2α, thus contributing to uninterrupted synthesis of viral proteins in the infected cells. IMPORTANCE Hepatitis E virus (HEV) is a major cause of acute viral hepatitis in humans. It causes chronic infection in organ transplant patients. Although the disease is self-limiting in normal individuals, it is associated with high mortality (~30%) in pregnant women. In an earlier study, we identified the interaction between the genotype 1 HEV protease (PCP) and cellular eukaryotic initiation factor 2 alpha kinase 4 (eIF2AK4). Since eIF2AK4 is a sensor of the cellular integrated stress response machinery, we evaluated the significance of the interaction between PCP and eIF2AK4. Here, we show that PCP competitively associates with and interferes with self-association of the eIF2AK4, thereby inhibiting its kinase activity. Lack of eIF2AK4 activity prevents phosphorylation-mediated inactivation of the cellular eIF2α, which is essential for initiation of cap-dependent translation. Thus, PCP behaves as a proviral factor, promoting uninterrupted synthesis of viral proteins in infected cells, which is crucial for survival and proliferation of the virus.
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Affiliation(s)
- Amit Kumar
- Virology Laboratory, Translational Health Science and Technology Institute, NCR Biotech Science Cluster, Faridabad, Haryana, India
| | - Chandru Subramani
- Virology Laboratory, Translational Health Science and Technology Institute, NCR Biotech Science Cluster, Faridabad, Haryana, India
| | - Shivani Raj
- University School of Biotechnology, Guru Gobind Singh Indraprastha University, New Delhi, India
| | - C. T. Ranjith-Kumar
- University School of Biotechnology, Guru Gobind Singh Indraprastha University, New Delhi, India
| | - Milan Surjit
- Virology Laboratory, Translational Health Science and Technology Institute, NCR Biotech Science Cluster, Faridabad, Haryana, India
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Ansari S, Gupta N, Verma R, Singh ON, Gupta J, Kumar A, Yadav MK, Binayke A, Tiwari M, Periwal N, Sood V, Mani S, Awasthi A, Shalimar, Nayak B, Ranjith‐Kumar CT, Surjit M. Antiviral activity of the human endogenous retrovirus‐R envelope protein against SARS‐CoV‐2. EMBO Rep 2023; 24:e55900. [PMCID: PMC10328075 DOI: 10.15252/embr.202255900] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2022] [Revised: 03/31/2023] [Accepted: 04/26/2023] [Indexed: 09/29/2023] Open
Abstract
Coronavirus‐induced disease‐19 (COVID‐19), caused by SARS‐CoV‐2, is still a major global health challenge. Human endogenous retroviruses (HERVs) represent retroviral elements that were integrated into the ancestral human genome. HERVs are important in embryonic development as well as in the manifestation of diseases, including cancer, inflammation, and viral infections. Here, we analyze the expression of several HERVs in SARS‐CoV‐2‐infected cells and observe increased activity of HERV‐E, HERV‐V, HERV‐FRD, HERV‐MER34, HERV‐W, and HERV‐K‐HML2. In contrast, the HERV‐R envelope is downregulated in cell‐based models and PBMCs of COVID‐19 patients. Overexpression of HERV‐R inhibits SARS‐CoV‐2 replication, suggesting its antiviral activity. Further analyses demonstrate the role of the extracellular signal‐regulated kinase (ERK) in regulating HERV‐R antiviral activity. Lastly, our data indicate that the crosstalk between ERK and p38 MAPK controls the synthesis of the HERV‐R envelope protein, which in turn modulates SARS‐CoV‐2 replication. These findings suggest the role of the HERV‐R envelope as a prosurvival host factor against SARS‐CoV‐2 and illustrate a possible advantage of integration and evolutionary maintenance of retroviral elements in the human genome.
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Affiliation(s)
- Shabnam Ansari
- Virology LaboratoryTranslational Health Science and Technology Institute, NCR Biotech Science ClusterFaridabadIndia
| | - Nidhi Gupta
- Virology LaboratoryTranslational Health Science and Technology Institute, NCR Biotech Science ClusterFaridabadIndia
- Present address:
Department of BiochemistryAll India Institute of Medical SciencesNew DelhiIndia
| | - Rohit Verma
- Virology LaboratoryTranslational Health Science and Technology Institute, NCR Biotech Science ClusterFaridabadIndia
| | - Oinam N Singh
- Virology LaboratoryTranslational Health Science and Technology Institute, NCR Biotech Science ClusterFaridabadIndia
| | - Jyoti Gupta
- Virology LaboratoryTranslational Health Science and Technology Institute, NCR Biotech Science ClusterFaridabadIndia
| | - Amit Kumar
- Virology LaboratoryTranslational Health Science and Technology Institute, NCR Biotech Science ClusterFaridabadIndia
| | - Mukesh Kumar Yadav
- Virology LaboratoryTranslational Health Science and Technology Institute, NCR Biotech Science ClusterFaridabadIndia
| | - Akshay Binayke
- Immunobiology LaboratoryTranslational Health Science and Technology Institute, NCR Biotech Science ClusterFaridabadIndia
| | - Mahima Tiwari
- Translational Health Science and Technology Institute, NCR Biotech Science ClusterFaridabadIndia
| | - Neha Periwal
- Department of Biochemistry, School of Chemical and Life SciencesJamia Hamdard UniversityNew DelhiIndia
| | - Vikas Sood
- Department of Biochemistry, School of Chemical and Life SciencesJamia Hamdard UniversityNew DelhiIndia
| | - Shailendra Mani
- Translational Health Science and Technology Institute, NCR Biotech Science ClusterFaridabadIndia
| | - Amit Awasthi
- Immunobiology LaboratoryTranslational Health Science and Technology Institute, NCR Biotech Science ClusterFaridabadIndia
| | - Shalimar
- Department of GastroenterologyAll India Institute of Medical SciencesNew DelhiIndia
| | - Baibaswata Nayak
- Department of GastroenterologyAll India Institute of Medical SciencesNew DelhiIndia
| | - CT Ranjith‐Kumar
- University School of Biotechnology, Guru Gobind Singh Indraprastha UniversityNew DelhiIndia
| | - Milan Surjit
- Virology LaboratoryTranslational Health Science and Technology Institute, NCR Biotech Science ClusterFaridabadIndia
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Srivastava M, Bhukya PL, Barman MK, Bhise N, Lole KS. Modulation of cellular autophagy by genotype 1 hepatitis E virus ORF3 protein. J Gen Virol 2023; 104. [PMID: 36809248 DOI: 10.1099/jgv.0.001824] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/23/2023] Open
Abstract
Hepatitis E virus (HEV) egresses from infected hepatocytes as quasienveloped particles containing open reading frame 3 (ORF3) protein. HEV ORF3 (small phosphoprotein) interacts with host proteins to establish a favourable environment for virus replication. It is a functional viroporin that plays an important role during virus release. Our study provides evidence that pORF3 plays a pivotal role in inducing Beclin1-mediated autophagy that helps HEV-1 replication as well as its exit from cells. The ORF3 interacts with host proteins involved in regulation of transcriptional activity, immune response, cellular and molecular processes, and modulation of autophagy, by interacting with proteins, DAPK1, ATG2B, ATG16L2 and also several histone deacetylases (HDACs). For autophagy induction, the ORF3 utilizes non-canonical NF-κB2 pathway and sequesters p52NF-κB and HDAC2 to upregulate DAPK1 expression, leading to enhanced Beclin1 phosphorylation. By sequestering several HDACs, HEV may prevent histone deacetylation to maintain overall cellular transcription intact to promote cell survival. Our findings highlight a novel crosstalk between cell survival pathways participating in ORF3-mediated autophagy.
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Affiliation(s)
| | - Prudhvi Lal Bhukya
- Division of Hepatitis, National Institute of Virology, Pune, India
- ICMR-National Animal Resource Facility for Biomedical Research, Hyderabad, India
| | | | - Neha Bhise
- Division of Hepatitis, National Institute of Virology, Pune, India
| | - Kavita S Lole
- Division of Hepatitis, National Institute of Virology, Pune, India
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10
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Zhou Y, Zhao C, Tian Y, Xu N, Wang Y. Characteristics and Functions of HEV Proteins. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2023; 1417:15-32. [PMID: 37223856 DOI: 10.1007/978-981-99-1304-6_2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
Hepatitis E virus (HEV) is a non-enveloped virus containing a single-stranded, positive-sense RNA genome of 7.2 kb, which consists of a 5' non-coding region, three open reading frames (ORFs), and a 3' non-coding region. ORF1 is diverse between genotypes and encodes the nonstructural proteins, which include the enzymes needed for virus replication. In addition to its role in virus replication, the function of ORF1 is relevant to viral adaption in culture and may also relate to virus infection and HEV pathogenicity. ORF2 protein is the capsid protein, which is about 660 amino acids in length. It not only protects the integrity of the viral genome, but is also involved in many important physiological activities, such as virus assembly, infection, host interaction, and innate immune response. The main immune epitopes, especially neutralizing epitopes, are located on ORF2 protein, which is a candidate antigen for vaccine development. ORF3 protein is a phosphoprotein of 113 or 114 amino acids with a molecular weight of 13 kDa with multiple functions that can also induce strong immune reactivity. A novel ORF4 has been identified only in genotype 1 HEV and its translation promotes viral replication.
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Affiliation(s)
- Yan Zhou
- RegCMC, Great Regulatory Affairs, Sanofi (China) Investment Co., Ltd, Beijing, China
| | - Chenyan Zhao
- Division of HIV/AIDS and Sex-Transmitted Virus Vaccines, National Institutes for Food and Drug Control, Beijing, China
| | - Yabin Tian
- Division II of In Vitro Diagnostics for Infectious Diseases, National Institutes for Food and Drug Control, Beijing, China
| | - Nan Xu
- Division of HIV/AIDS and Sex-Transmitted Virus Vaccines, National Institutes for Food and Drug Control, Beijing, China
| | - Youchun Wang
- Institute of Medical Biology, Chinese Academy of Medical Science & Peking Union Medical College, Kunming, China.
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11
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Sayed IM, Karam-Allah Ramadan H, Hafez MHR, Elkhawaga AA, El-Mokhtar MA. Hepatitis E virus (HEV) open reading frame 2: Role in pathogenesis and diagnosis in HEV infections. Rev Med Virol 2022; 32:e2401. [PMID: 36209386 DOI: 10.1002/rmv.2401] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2022] [Revised: 09/27/2022] [Accepted: 09/28/2022] [Indexed: 11/12/2022]
Abstract
Hepatitis E virus (HEV) infection occurs worldwide. The HEV genome includes three to four open reading frames (ORF1-4). ORF1 proteins are essential for viral replication, while the ORF3 protein is an ion channel involved in the exit of HEV from the infected cells. ORF2 proteins form the viral capsid required for HEV invasion and assembly. They also suppress interferon production and inhibit antibody-mediated neutralisation of HEV, allowing the virus to hijack the host immune response. ORF2 is the only detectable viral protein in the human liver during HEV infection and it is secreted in the plasma, stool, and urine of HEV-infected patients, making it a reliable diagnostic marker. The plasma HEV ORF2 antigen level can predict the outcome of HEV infections. Hence, monitoring HEV ORF2 antigen levels may be useful in assessing the efficacy of anti-HEV therapy. The ORF2 antigen is immunogenic and includes epitopes that can induce neutralising antibodies; therefore, it is a potential HEV vaccine candidate. In this review, we highlighted the different forms of HEV ORF2 protein and their roles in HEV pathogenesis, diagnosis, monitoring the therapeutic efficacy, and vaccine development.
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Affiliation(s)
- Ibrahim M Sayed
- Department of Medical Microbiology and Immunology, Faculty of Medicine, Assiut University, Assiut, Egypt
| | - Haidi Karam-Allah Ramadan
- Department of Tropical Medicine and Gastroenterology, Faculty of Medicine, Assiut University, Assiut, Egypt
| | - Mahmoud H R Hafez
- International Scholar, African Leadership Academy, Johannesburg, South Africa
| | - Amal A Elkhawaga
- Department of Medical Microbiology and Immunology, Faculty of Medicine, Assiut University, Assiut, Egypt
| | - Mohamed A El-Mokhtar
- Department of Medical Microbiology and Immunology, Faculty of Medicine, Assiut University, Assiut, Egypt.,Microbiology and Immunology Department, Faculty of Pharmacy, Sphinx University, Assiut, Egypt
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12
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Cancela F, Noceti O, Arbiza J, Mirazo S. Structural aspects of hepatitis E virus. Arch Virol 2022; 167:2457-2481. [PMID: 36098802 PMCID: PMC9469829 DOI: 10.1007/s00705-022-05575-8] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2022] [Accepted: 06/04/2022] [Indexed: 12/14/2022]
Abstract
Hepatitis E virus (HEV) is a leading cause of acute hepatitis worldwide. Hepatitis E is an enterically transmitted zoonotic disease that causes large waterborne epidemic outbreaks in developing countries and has become an increasing public-health concern in industrialized countries. In this setting, the infection is usually acute and self-limiting in immunocompetent individuals, although chronic cases in immunocompromised patients have been reported, frequently associated with several extrahepatic manifestations. Moreover, extrahepatic manifestations have also been reported in immunocompetent individuals with acute HEV infection. HEV belongs to the alphavirus-like supergroup III of single-stranded positive-sense RNA viruses, and its genome contains three partially overlapping open reading frames (ORFs). ORF1 encodes a nonstructural protein with eight domains, most of which have not been extensively characterized: methyltransferase, Y domain, papain-like cysteine protease, hypervariable region, proline-rich region, X domain, Hel domain, and RNA-dependent RNA polymerase. ORF2 and ORF3 encode the capsid protein and a multifunctional protein believed to be involved in virion release, respectively. The novel ORF4 is only expressed in HEV genotype 1 under endoplasmic reticulum stress conditions, and its exact function has not yet been elucidated. Despite important advances in recent years, the biological and molecular processes underlying HEV replication remain poorly understood, primarily due to a lack of detailed information about the functions of the viral proteins and the mechanisms involved in host-pathogen interactions. This review summarizes the current knowledge concerning HEV proteins and their biological properties, providing updated detailed data describing their function and focusing in detail on their structural characteristics. Furthermore, we review some unclear aspects of the four proteins encoded by the ORFs, highlighting the current key information gaps and discussing potential novel experimental strategies for shedding light on those issues.
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Affiliation(s)
- Florencia Cancela
- grid.11630.350000000121657640Sección Virología, Facultad de Ciencias, Universidad de la República, Montevideo, Uruguay
| | - Ofelia Noceti
- grid.414402.70000 0004 0469 0889Programa Nacional de Trasplante Hepático y Unidad Docente Asistencial Centro Nacional de Tratamiento Hepatobiliopancreatico. Hospital Central de las Fuerzas Armadas, Montevideo, Uruguay
| | - Juan Arbiza
- grid.11630.350000000121657640Sección Virología, Facultad de Ciencias, Universidad de la República, Montevideo, Uruguay
| | - Santiago Mirazo
- grid.11630.350000000121657640Sección Virología, Facultad de Ciencias, Universidad de la República, Montevideo, Uruguay ,grid.11630.350000000121657640Departamento de Bacteriología y Virología, Instituto de Higiene, Facultad de Medicina, Universidad de la República, Montevideo, Uruguay ,Av. Alfredo Navarro 3051, PC 11600 Montevideo, Uruguay
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13
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Xu C, Chen J, Chen X. Host Innate Immunity Against Hepatitis Viruses and Viral Immune Evasion. Front Microbiol 2021; 12:740464. [PMID: 34803956 PMCID: PMC8598044 DOI: 10.3389/fmicb.2021.740464] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2021] [Accepted: 09/29/2021] [Indexed: 11/13/2022] Open
Abstract
Hepatitis viruses are primary causative agents of hepatitis and represent a major source of public health problems in the world. The host innate immune system forms the first line of defense against hepatitis viruses. Hepatitis viruses are sensed by specific pathogen recognition receptors (PRRs) that subsequently trigger the innate immune response and interferon (IFN) production. However, hepatitis viruses evade host immune surveillance via multiple strategies, which help compromise the innate immune response and create a favorable environment for viral replication. Therefore, this article reviews published findings regarding host innate immune sensing and response against hepatitis viruses. Furthermore, we also focus on how hepatitis viruses abrogate the antiviral effects of the host innate immune system.
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Affiliation(s)
- Chonghui Xu
- State Key Laboratory of Virology, Wuhan Institute of Virology, Center for Biosafety Mega-Science, Chinese Academy of Sciences, Wuhan, China.,University of Chinese Academy of Sciences, Beijing, China
| | - Jizheng Chen
- State Key Laboratory of Virology, Wuhan Institute of Virology, Center for Biosafety Mega-Science, Chinese Academy of Sciences, Wuhan, China.,Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou, China
| | - Xinwen Chen
- State Key Laboratory of Virology, Wuhan Institute of Virology, Center for Biosafety Mega-Science, Chinese Academy of Sciences, Wuhan, China.,Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou, China
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14
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Zhou Z, Xie Y, Wu C, Nan Y. The Hepatitis E Virus Open Reading Frame 2 Protein: Beyond Viral Capsid. Front Microbiol 2021; 12:739124. [PMID: 34690982 PMCID: PMC8529240 DOI: 10.3389/fmicb.2021.739124] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2021] [Accepted: 09/20/2021] [Indexed: 12/20/2022] Open
Abstract
Hepatitis E virus (HEV) is a zoonotic pathogen causing hepatitis in both human and animal hosts, which is responsible for acute hepatitis E outbreaks worldwide. The 7.2 kb genome of the HEV encodes three well-defined open reading frames (ORFs), where the ORF2 translation product acts as the major virion component to form the viral capsid. In recent years, besides forming the capsid, more functions have been revealed for the HEV-ORF2 protein, and it appears that HEV-ORF2 plays multiple functions in both viral replication and pathogenesis. In this review, we systematically summarize the recent research advances regarding the function of the HEV-ORF2 protein such as application in the development of a vaccine, regulation of the innate immune response and cellular signaling, involvement in host tropism and participation in HEV pathogenesis as a novel secretory factor. Progress in understanding more of the function of HEV-ORF2 protein beyond the capsid protein would contribute to improved control and treatment of HEV infection.
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Affiliation(s)
- Zhaobin Zhou
- Department of Preventive Veterinary Medicine, College of Veterinary Medicine, Northwest A&F University, Yangling, China
- Scientific Observing and Experimental Station of Veterinary Pharmacology and Diagnostic Technology, Ministry of Agriculture, Yangling, China
| | - Yinqian Xie
- Shaanxi Animal Disease Prevention and Control Center, Xi’an, China
| | - Chunyan Wu
- Department of Preventive Veterinary Medicine, College of Veterinary Medicine, Northwest A&F University, Yangling, China
- Scientific Observing and Experimental Station of Veterinary Pharmacology and Diagnostic Technology, Ministry of Agriculture, Yangling, China
| | - Yuchen Nan
- Department of Preventive Veterinary Medicine, College of Veterinary Medicine, Northwest A&F University, Yangling, China
- Scientific Observing and Experimental Station of Veterinary Pharmacology and Diagnostic Technology, Ministry of Agriculture, Yangling, China
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15
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Interplay between Hepatitis E Virus and Host Cell Pattern Recognition Receptors. Int J Mol Sci 2021; 22:ijms22179259. [PMID: 34502167 PMCID: PMC8431321 DOI: 10.3390/ijms22179259] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2021] [Revised: 08/02/2021] [Accepted: 08/06/2021] [Indexed: 11/23/2022] Open
Abstract
Hepatitis E virus (HEV) usually causes self-limiting acute hepatitis, but the disease can become chronic in immunocompromised individuals. HEV infection in pregnant women is reported to cause up to 30% mortality, especially in the third trimester. Additionally, extrahepatic manifestations like neuronal and renal diseases and pancreatitis are also reported during the course of HEV infection. The mechanism of HEV pathogenesis remains poorly understood. Innate immunity is the first line of defense triggered within minutes to hours after the first pathogenic insult. Growing evidence based on reverse genetics systems, in vitro cell culture models, and representative studies in animal models including non-human primates, has implicated the role of the host’s innate immune response during HEV infection. HEV persists in presence of interferons (IFNs) plausibly by evading cellular antiviral defense. This review summarizes our current understanding of recognizing HEV-associated molecular patterns by host cell Pattern Recognition Receptors (PRRs) in eliciting innate immune response during HEV infection as well as mechanisms of virus-mediated immune evasion.
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16
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Sayed IM, Abd Elhameed ZA, Abd El-Kareem DM, Abdel-Malek MAY, Ali ME, Ibrahim MA, Sayed AAR, Khalaf KAB, Abdel-Wahid L, El-Mokhtar MA. Hepatitis E Virus Persistence and/or Replication in the Peripheral Blood Mononuclear Cells of Acute HEV-Infected Patients. Front Microbiol 2021; 12:696680. [PMID: 34335528 PMCID: PMC8322848 DOI: 10.3389/fmicb.2021.696680] [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: 04/17/2021] [Accepted: 06/11/2021] [Indexed: 12/15/2022] Open
Abstract
BACKGROUND Hepatitis E virus (HEV) causes about 14 million infections with 300,000 deaths and 5,200 stillbirths worldwide annually. Extrahepatic manifestations are reported with HEV infections, such as renal, neurological, and hematological disorders. Recently, we reported that stool-derived HEV-1 replicates efficiently in human monocytes and macrophages in vitro. However, another study reports the presence of viral RNA but no evidence of replication in the PBMCs of acute hepatitis E (AHE) patients. Therefore, the replication of HEV in PBMCs during AHE infection is not completely understood. METHODS PBMCs were isolated from AHE patients (n = 17) enrolled in Assiut University Hospitals, Egypt. The viral load, positive (+) and negative (-) HEV RNA strands and viral protein were assessed. The gene expression profile of PBMCs from AHE patients was assessed. In addition, the level of cytokines was measured in the plasma of the patients. RESULTS HEV RNA was detected in the PBMCs of AHE patients. The median HEV load in the PBMCs was 1.34 × 103 IU/ml. A negative HEV RNA strand and HEV open reading frame 2 protein were recorded in 4/17 (23.5%) of the PBMCs. Upregulation of inflammatory transcripts and increased plasma cytokines were recorded in the AHE patients compared with healthy individuals with significantly elevated transcripts and plasma cytokines in the AHE with detectable (+) and (-) RNA strands compared with the AHE with the detectable (+) RNA strand only. There was no significant difference in terms of age, sex, and liver function tests between AHE patients with detectable (+) and (-) RNA strands in the PBMCs and AHE patients with the (+) RNA strand only. CONCLUSION Our study shows evidence for in vivo HEV persistence and replication in the PBMCs of AHE patients. The replication of HEV in the PBMCs was associated with an enhanced immune response, which could affect the pathogenesis of HEV.
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Affiliation(s)
- Ibrahim M. Sayed
- Department of Medical Microbiology and Immunology, Faculty of Medicine, Assiut University, Assiut, Egypt
- Department of Pathology, School of Medicine, University of California, San Diego, La Jolla, CA, United States
| | | | - Doaa M. Abd El-Kareem
- Department of Clinical Pathology, Faculty of Medicine Assiut University, Assiut, Egypt
| | | | - Mohamed E. Ali
- Department of Microbiology and Immunology, Faculty of Pharmacy, Al-Azhar University, Assiut, Egypt
| | - Maggie A. Ibrahim
- Department of Medical Microbiology and Immunology, Faculty of Medicine, Assiut University, Assiut, Egypt
| | | | - Khaled Abo bakr Khalaf
- Department of Tropical Medicine and Gastroenterology, Faculty of Medicine, Assiut University, Assiut, Egypt
| | - Lobna Abdel-Wahid
- Gastroenterology and Hepatology Unit, Department of Internal Medicine, Faculty of Medicine, Assiut University, Assiut, Egypt
| | - Mohamed A. El-Mokhtar
- Department of Medical Microbiology and Immunology, Faculty of Medicine, Assiut University, Assiut, Egypt
- Microbiology and Immunology Department, Faculty of Pharmacy, Sphinx University, Assiut, Egypt
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17
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El-Mokhtar MA, Karam-Allah Ramadan H, Abdel Hameed MR, M Kamel A, A Mandour S, Ali M, Abdel-Malek MAY, M Abd El-Kareem D, Adel S, H Salama E, Khalaf KAB, Sayed IM. Evaluation of hepatitis E antigen kinetics and its diagnostic utility for prediction of the outcomes of hepatitis E virus genotype 1 infection. Virulence 2021; 12:1334-1344. [PMID: 34002677 PMCID: PMC8143225 DOI: 10.1080/21505594.2021.1922027] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
HEV-Ag ELISA assay is a reliable diagnostic test in resource-limited areas. HEV genotype 1 (HEV-1) infections are either self-limited or progress to fulminant hepatic failure (FHF) and death if anti-HEV therapy is delayed. Limited data is available about the diagnostic utility of HEV Ag on HEV-1 infections. Herein wWe aimed to study the kinetics of HEV Ag during HEV-1 infections at different stages, i.e., acute HEV infection, recovery, and progression to FHF. Also, we evaluated the diagnostic utility of this marker to predict the outcomes of HEV-1 infections. Plasma of acute hepatitis E (AHE) patients were assessed for HEV RNA by RT-qPCR, HEV Ag, and anti-HEV IgM by ELISA. The kinetics of HEV Ag was monitored at different time points; acute phase of infection, recovery, FHF stage, and post-recovery. Our results showed that the level of HEV Ag was elevated in AHE patients with a significantly higher level in FHF patients than recovered patients. We identified a plasma HEV Ag threshold that can differentiate between self-limiting infection and FHF progression with 100% sensitivity and 88.89% specificity. HEV Ag and HEV RNA have similar kinetics during the acute phase and self-limiting infection. In the FHF stage, HEV Ag and anti-HEV IgM have similar patterns of kinetics which could be the cause of liver damage. In conclusion, the HEV Ag assay can be used as a biomarker for predicting the consequences of HEV-1 infections which could be diagnostically useful for taking the appropriate measures to reduce the complications, especially for high-risk groups.
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Affiliation(s)
- Mohamed A El-Mokhtar
- Department of Medical Microbiology and Immunology, Faculty of Medicine, Assiut University, Assiut, Egypt.,Microbiology and Immunology Department, Faculty of Pharmacy, Sphinx University, Assiut, Egypt
| | - Haidi Karam-Allah Ramadan
- Department of Tropical Medicine and Gastroenterology, Faculty of Medicine, Assiut University, Assiut, Egypt
| | - Muhamad R Abdel Hameed
- Department of Internal Medicine and Hematology Unit, Assiut University Hospitals, Assiut University, Assiut, Egypt
| | - Ayat M Kamel
- Microbiology and Immunology Department, Faculty of Pharmacy, Assiut University, Assiut Egypt
| | - Sahar A Mandour
- Department of Microbiology and Immunology, Faculty of Pharmacy, Deraya University, Minia, Egypt
| | - Maha Ali
- Department of Medical Biochemistry, Faculty of Medicine, Assiut University, Egypt
| | | | | | - Sara Adel
- Department of Clinical Pathology, Faculty of Medicine, Al-Azhar University, Assiut, Egypt
| | - Eman H Salama
- Department of Clinical Pathology, Faculty of Medicine, Sohag University, Sohag, Egypt
| | - Khaled Abo Bakr Khalaf
- Department of Tropical Medicine and Gastroenterology, Faculty of Medicine, Assiut University, Assiut, Egypt
| | - Ibrahim M Sayed
- Department of Medical Microbiology and Immunology, Faculty of Medicine, Assiut University, Assiut, Egypt.,Department of Pathology, School of Medicine, University of California, San Diego, La Jolla, California, USA
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18
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El-Mokhtar MA, Sayed IM. Model systems for studying extrahepatic pathogenesis of hepatitis E virus. Current knowledge and future directions. Rev Med Virol 2021; 31:e2218. [PMID: 33475223 DOI: 10.1002/rmv.2218] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2020] [Accepted: 01/05/2021] [Indexed: 02/06/2023]
Abstract
Hepatitis E Virus is the most common cause of acute viral hepatitis globally. HEV infection is endemic in developing countries. Also, autochthonous and sporadic cases are reported in developed countries. HEV causes acute and chronic infections. Besides, extrahepatic manifestations including neurological, renal, haematological, acute pancreatitis and complications during pregnancy are associated with HEV infections. The pathogenesis of HEV in the extrahepatic tissues is either due to direct cytopathic effect mediated by the virus replication, or immunological mechanisms caused by an uncontrollable host response. Researchers have used different in vivo and in vitro models to study the pathogenesis of HEV in the extrahepatic tissues and analyse the host immune response against HEV infection. This review highlights the extrahepatic disorders associated with HEV infection. We focused on the in vivo and in vitro models as a tool for elucidating the HEV infection beyond the liver and studying the mechanisms of HEV induced tissue damages.
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Affiliation(s)
- Mohamed A El-Mokhtar
- Department of Medical Microbiology and Immunology, Faculty of Medicine, Assiut University, Assiut, Egypt.,Microbiology and Immunology Department, Faculty of Pharmacy, Sphinx University, Assiut, Egypt
| | - Ibrahim M Sayed
- Department of Medical Microbiology and Immunology, Faculty of Medicine, Assiut University, Assiut, Egypt.,Department of Pathology, School of Medicine, University of California, San Diego La Jolla, California, USA
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19
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Yadav KK, Boley PA, Fritts Z, Kenney SP. Ectopic Expression of Genotype 1 Hepatitis E Virus ORF4 Increases Genotype 3 HEV Viral Replication in Cell Culture. Viruses 2021; 13:v13010075. [PMID: 33430442 PMCID: PMC7827316 DOI: 10.3390/v13010075] [Citation(s) in RCA: 31] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2020] [Revised: 01/05/2021] [Accepted: 01/05/2021] [Indexed: 02/07/2023] Open
Abstract
Hepatitis E virus (HEV) can account for up to a 30% mortality rate in pregnant women, with highest incidences reported for genotype 1 (gt1) HEV. Reasons contributing to adverse maternal-fetal outcome during pregnancy in HEV-infected pregnant women remain elusive in part due to the lack of a robust tissue culture model for some strains. Open reading frame (ORF4) was discovered overlapping ORF1 in gt1 HEV whose protein expression is regulated via an IRES-like RNA element. To experimentally determine whether gt3 HEV contains an ORF4-like gt1, gt1 and gt3 sequence comparisons were performed between the gt1 and the homologous gt3 sequence. To assess whether ORF4 protein could enhance gt3 replication, Huh7 cell lines constitutively expressing ORF4 were created and used to assess the replication of the Kernow-C1 gt3 and sar55 gt1 HEV. Virus stocks from transfected Huh7 cells with or without ORF4 were harvested and infectivity assessed via infection of HepG2/C3A cells. We also studied the replication of gt1 HEV in the ORF4-expressing tunicamycin-treated cell line. To directly show that HEV transcripts have productively replicated in the target cells, we assessed events at the single-cell level using indirect immunofluorescence and flow cytometry. Despite not naturally encoding ORF4, replication of gt3 HEV was enhanced by the presence of gt1 ORF4 protein. These results suggest that the function of ORF4 protein from gt1 HEV is transferrable, enhancing the replication of gt3 HEV. ORF4 may be utilized to enhance replication of difficult to propagate HEV genotypes in cell culture. IMPORTANCE: HEV is a leading cause of acute viral hepatitis (AVH) around the world. The virus is a threat to pregnant women, particularly during the second and third trimester of pregnancy. The factors enhancing virulence to pregnant populations are understudied. Additionally, field strains of HEV remain difficult to culture in vitro. ORF4 was recently discovered in gt1 HEV and is purported to play a role in pregnancy related pathology and enhanced replication. We present evidence that ORF4 protein provided in trans enhances the viral replication of gt3 HEV even though it does not encode ORF4 naturally in its genome. These data will aid in the development of cell lines capable of supporting replication of non-cell culture adapted HEV field strains, allowing viral titers sufficient for studying these strains in vitro. Furthermore, development of gt1/gt3 ORF4 chimeric virus may shed light on the role that ORF4 plays during pregnancy.
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Affiliation(s)
- Kush K. Yadav
- Food Animal Health Research Program, Ohio Agricultural Research and Development Center (OARDC), The Ohio State University, Wooster, OH 44691, USA; (K.K.Y.); (P.A.B.)
| | - Patricia A. Boley
- Food Animal Health Research Program, Ohio Agricultural Research and Development Center (OARDC), The Ohio State University, Wooster, OH 44691, USA; (K.K.Y.); (P.A.B.)
| | - Zachary Fritts
- Department of Electrical and Computer Engineering, University of Michigan, Ann Arbor, MI 48105, USA;
| | - Scott P. Kenney
- Food Animal Health Research Program, Ohio Agricultural Research and Development Center (OARDC), The Ohio State University, Wooster, OH 44691, USA; (K.K.Y.); (P.A.B.)
- Correspondence:
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20
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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: 2.0] [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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