1
|
Zahmanova G, Takova K, Tonova V, Koynarski T, Lukov LL, Minkov I, Pishmisheva M, Kotsev S, Tsachev I, Baymakova M, Andonov AP. The Re-Emergence of Hepatitis E Virus in Europe and Vaccine Development. Viruses 2023; 15:1558. [PMID: 37515244 PMCID: PMC10383931 DOI: 10.3390/v15071558] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2023] [Revised: 07/11/2023] [Accepted: 07/13/2023] [Indexed: 07/30/2023] Open
Abstract
Hepatitis E virus (HEV) is one of the leading causes of acute viral hepatitis. Transmission of HEV mainly occurs via the fecal-oral route (ingesting contaminated water or food) or by contact with infected animals and their raw meat products. Some animals, such as pigs, wild boars, sheep, goats, rabbits, camels, rats, etc., are natural reservoirs of HEV, which places people in close contact with them at increased risk of HEV disease. Although hepatitis E is a self-limiting infection, it could also lead to severe illness, particularly among pregnant women, or chronic infection in immunocompromised people. A growing number of studies point out that HEV can be classified as a re-emerging virus in developed countries. Preventative efforts are needed to reduce the incidence of acute and chronic hepatitis E in non-endemic and endemic countries. There is a recombinant HEV vaccine, but it is approved for use and commercially available only in China and Pakistan. However, further studies are needed to demonstrate the necessity of applying a preventive vaccine and to create conditions for reducing the spread of HEV. This review emphasizes the hepatitis E virus and its importance for public health in Europe, the methods of virus transmission and treatment, and summarizes the latest studies on HEV vaccine development.
Collapse
Affiliation(s)
- Gergana Zahmanova
- Department of Plant Physiology and Molecular Biology, University of Plovdiv, 4000 Plovdiv, Bulgaria
- Department of Technology Transfer and IP Management, Center of Plant Systems Biology and Biotechnology, 4000 Plovdiv, Bulgaria
| | - Katerina Takova
- Department of Plant Physiology and Molecular Biology, University of Plovdiv, 4000 Plovdiv, Bulgaria
| | - Valeria Tonova
- Department of Plant Physiology and Molecular Biology, University of Plovdiv, 4000 Plovdiv, Bulgaria
| | - Tsvetoslav Koynarski
- Department of Animal Genetics, Faculty of Veterinary Medicine, Trakia University, 6000 Stara Zagora, Bulgaria
| | - Laura L Lukov
- Faculty of Sciences, Brigham Young University-Hawaii, Laie, HI 96762, USA
| | - Ivan Minkov
- Department of Technology Transfer and IP Management, Center of Plant Systems Biology and Biotechnology, 4000 Plovdiv, Bulgaria
- Institute of Molecular Biology and Biotechnologies, 4108 Markovo, Bulgaria
| | - Maria Pishmisheva
- Department of Infectious Diseases, Pazardzhik Multiprofile Hospital for Active Treatment, 4400 Pazardzhik, Bulgaria
| | - Stanislav Kotsev
- Department of Infectious Diseases, Pazardzhik Multiprofile Hospital for Active Treatment, 4400 Pazardzhik, Bulgaria
| | - Ilia Tsachev
- Department of Microbiology, Infectious and Parasitic Diseases, Faculty of Veterinary Medicine, Trakia University, 6000 Stara Zagora, Bulgaria
| | - Magdalena Baymakova
- Department of Infectious Diseases, Military Medical Academy, 1606 Sofia, Bulgaria
| | - Anton P Andonov
- Department of Medical Microbiology and Infectious Diseases, Max Rady College of Medicine, University of Manitoba, Winnipeg, MB R3T 2N2, Canada
| |
Collapse
|
2
|
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.
Collapse
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
| |
Collapse
|
3
|
Nan Y, Wu C, Zhao Q, Sun Y, Zhang YJ, Zhou EM. Vaccine Development against Zoonotic Hepatitis E Virus: Open Questions and Remaining Challenges. Front Microbiol 2018; 9:266. [PMID: 29520257 PMCID: PMC5827553 DOI: 10.3389/fmicb.2018.00266] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2017] [Accepted: 02/05/2018] [Indexed: 12/18/2022] Open
Abstract
Hepatitis E virus (HEV) is a fecal-orally transmitted foodborne viral pathogen that causes acute hepatitis in humans and is responsible for hepatitis E outbreaks worldwide. Since the discovery of HEV as a zoonotic agent, this virus has been isolated from a variety of hosts with an ever-expanding host range. Recently, a subunit HEV vaccine developed for the prevention of human disease was approved in China, but is not yet available to the rest of the world. Meanwhile, notable progress and knowledge has been made and revealed in recent years to better understand HEV biology and infection, including discoveries of quasi-enveloped HEV virions and of a new function of the HEV-ORF3 product. However, the impact of these new findings on the development of a protective vaccine against zoonotic HEV infection requires further discussion. In this review, hallmark characteristics of HEV zoonosis, the history of HEV vaccine development, and recent discoveries in HEV virology are described. Moreover, special attention is focused on quasi-enveloped HEV virions and the potential role of the HEV-ORF3 product as antibody-neutralization target on the surface of quasi-enveloped HEV virions to provide new insights for the future development of improved vaccines against zoonotic HEV infection.
Collapse
Affiliation(s)
- 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
| | - 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
| | - Qin Zhao
- 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
| | - Yani Sun
- 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
| | - Yan-Jin Zhang
- Molecular Virology Laboratory, VA-MD College of Veterinary Medicine and Maryland Pathogen Research Institute, University of Maryland, College Park, MD, United States
| | - En-Min 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
| |
Collapse
|
4
|
Taherkhani R, Farshadpour F. Epidemiology of Hepatitis E in Pregnant Women and Children in Iran: A General Overview. J Clin Transl Hepatol 2016; 4:269-276. [PMID: 27777896 PMCID: PMC5075011 DOI: 10.14218/jcth.2016.00013] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/29/2016] [Revised: 08/01/2016] [Accepted: 08/18/2016] [Indexed: 02/06/2023] Open
Abstract
From an epidemiological point of view, hepatitis E is an old infection in Iran, but only recently has its importance as a public health concern been considered from research and public health standpoints. As such, there is still a long road ahead to clarify the real burden of hepatitis E virus (HEV) infection in Iran. According to the available epidemiological studies, the seroprevalence of HEV infection among pregnant women is between 3.6% and 7.4%, and among Iranian children is between 0.9% to 8.5%, varying by geographic regions within the country and directly dependent upon the sanitary status of each. In addition to evaluating the sanitation level of a society, community-based seroprevalence studies of HEV infection demonstrate the most prevalent risk factors, the major routes of transmission, and the epidemiological patterns of HEV among that country's population. In this review, the current knowledge about the pathogenesis and epidemiology of HEV infection in pregnant women and children in Iran, as well as the recent advances in diagnosis, prevention and treatment of HEV infection have been summarized.
Collapse
Affiliation(s)
- Reza Taherkhani
- Department of Microbiology and Parasitology, School of Medicine, Bushehr University of Medical Sciences, Bushehr, Iran
- Persian Gulf Biomedical Research Center, Bushehr University of Medical Sciences, Bushehr, Iran
| | - Fatemeh Farshadpour
- Department of Microbiology and Parasitology, School of Medicine, Bushehr University of Medical Sciences, Bushehr, Iran
- Persian Gulf Tropical Medicine Research Center, Bushehr University of Medical Sciences, Bushehr, Iran
- *Correspondence to: Fatemeh Farshadpour, Department of Microbiology and Parasitology, School of Medicine, Bushehr University of Medical Sciences, Moallem Street, P. O. Box 3631, Bushehr 7514633341, Iran. Tel: +98-9171712653, Fax: +98-7714550235, E-mail:
| |
Collapse
|
5
|
Kamili S. Toward the development of a hepatitis E vaccine. Virus Res 2011; 161:93-100. [PMID: 21620908 DOI: 10.1016/j.virusres.2011.05.008] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2011] [Revised: 05/04/2011] [Accepted: 05/10/2011] [Indexed: 12/15/2022]
Abstract
Hepatitis E virus (HEV) causes large epidemics of enterically transmitted acute hepatitis and accounts for a majority of sporadic acute hepatitis in endemic countries. Due to a very high mortality rate among infected pregnant women and substantial morbidity, disability and costs associated with hepatitis E, concerted efforts are being made to develop an efficacious vaccine. Experimental vaccines, based on recombinant proteins derived from the capsid gene of HEV, have been shown efficacious in pre-clinical trials in macaques conferring cross-protection against various genotypes. Two vaccine candidates, the rHEV vaccine expressed in baculovirus and the HEV 239 vaccine, expressed in Escherichia coli, were successfully evaluated in Phase II/III trials. However, at this time no approved vaccine against hepatitis E is commercially available.
Collapse
Affiliation(s)
- Saleem Kamili
- Centers for Disease Control and Prevention, National Center for HIV/Hepatitis/STD/TB Prevention, Division of Viral Hepatitis, Atlanta, GA 30333, USA.
| |
Collapse
|
6
|
Yang S, Wang C, Fang X, Zhai L, Dong C, Ding L, Meng J, Wang L. Fusion of C3d molecule with neutralization epitope(s) of hepatitis E virus enhances antibody avidity maturation and neutralizing activity following DNA immunization. Virus Res 2010; 151:162-9. [PMID: 20451569 DOI: 10.1016/j.virusres.2010.04.011] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2009] [Revised: 04/27/2010] [Accepted: 04/28/2010] [Indexed: 01/27/2023]
Abstract
Previous studies have identified that a hepatits E virus peptide (HEV-p179), spanning amino acids (aa) 439-617 in the 660-aa protein encoded by open reading frame 2(ORF2) of the Chinese epidemic strain (genotype 4), is the minimal size fragment of conformation-dependent neutralization epitope(s). We report here the successful immunization of mice with DNA vaccines expressing the secreted form of HEV-p179 (fused with a human tissue plasminogen activator (tPA) signal sequence) and the tPA-p179-C3d fusion protein (fused with three tandem copies of the murine complement C3d). Analysis of antibody responses in vaccinated mice revealed that immunizations with tPA-p179-C3d3 DNA vaccine dramatically increased both the level and avidity maturation of antibodies against HEV-p179 compared to p179 and tPA-p179 DNA vaccines. In addition, this increased antibody response correlated with neutralizing titers in a PCR-based cell culture neutralization assay. These results indicate that vaccination with C3d conjugated p179 DNA vaccine enhances antibody responses to HEV, and this approach may be applied to overcome the poor immunogenicity of DNA vaccines to generate HEV neutralizing antibodies.
Collapse
Affiliation(s)
- Shucai Yang
- Department of Microbiology and Immunology, Medical School of Southeast University, 87 Dingjiaqiao Rd., Nanjing, Jiangsu 210009, China.
| | | | | | | | | | | | | | | |
Collapse
|
7
|
Amini-Bavil-Olyaee S, Trautwein C, Tacke F. Hepatitis E vaccine: current status and future prospects. Future Virol 2009. [DOI: 10.2217/17460794.4.2.143] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
HEV, a positive ssRNA and nonenveloped virus, is endemic in many developing countries and one of the most frequent causes of acute hepatitis after fecal–oral transmission. Pregnant women are at particular risk for a fatal course of disease, including maternal and fetal mortality. Recent reports indicate that HEV genotype 3, possibly related to zoonotic transmission, may cause chronic hepatitis in some immunosuppressed organ transplant patients. Various approaches have been conducted to develop HEV vaccines, but only one candidate, a recombinant HEV (rHEV) vaccine generated from Spodoptera frugiperda-9 cells by baculoviruses expressing the HEV capsid antigen, has reached clinical Phase I and II trials so far. These trials suggest that the rHEV vaccine is safe and can prevent clinically overt acute hepatitis E in high-risk populations. We herein review the different approaches in HEV-vaccine development and critically discuss the current status and future directions of the rHEV vaccine used in clinical trials.
Collapse
Affiliation(s)
| | - Christian Trautwein
- Department of Medicine III, RWTH-University Hospital Aachen, Aachen, Germany
| | - Frank Tacke
- Department of Medicine III, RWTH-University Hospital Aachen, Aachen, Germany
| |
Collapse
|
8
|
Arankalle VA, Lole KS, Deshmukh TM, Srivastava S, Shaligram US. Challenge studies in Rhesus monkeys immunized with candidate hepatitis E vaccines: DNA, DNA-prime-protein-boost and DNA-protein encapsulated in liposomes. Vaccine 2008; 27:1032-9. [PMID: 19095027 DOI: 10.1016/j.vaccine.2008.11.097] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2008] [Revised: 11/19/2008] [Accepted: 11/28/2008] [Indexed: 10/21/2022]
Abstract
Complete ORF2 gene (1983bp) of hepatitis E virus (HEV) and the 450bp region within ORF2 containing neutralizing epitope (NE) cloned in pVAX1 and corresponding proteins expressed in baculovirus and prokaryotic systems respectively were evaluated as vaccine candidates. Two doses of liposome encapsulated DNA plus corresponding protein with both ORF2 and NE regions (Lipo-ORF2-DP and Lipo-NE-DP) showed 100% seroconversion and comparable anti-HEV titres in Swiss albino mice. These vaccine candidates were further evaluated as DNA, DNA-prime-protein-boost (DPPB) and liposome formulations in Rhesus monkeys. Monkeys receiving ORF2/NE DNA seroconverted after fourth dose while those immunized employing ORF2-DPPB format seroconverted at 7 weeks post third dose. In view of the delayed weak antibody response, these monkeys were not challenged. Though Lipo-ORF2-DP was immunogenic, 2 of the 4 monkeys developed HEV infection following homologous virus challenge of 100 Monkey Infectious Dose(50). Both monkeys immunized with Lipo-NE-DP and 1 of the 2 monkeys immunized with NE-DPPB showed complete protection, the second monkey being protected from hepatitis with limited viral replication. Irrespective of the type of immunogen, all challenged monkeys were protected from hepatitis. The results document Lipo-NE-DP to be a promising vaccine candidate needing further evaluation.
Collapse
Affiliation(s)
- Vidya A Arankalle
- Hepatitis Division, National Institute of Virology, Microbial Containment Complex, Sus Road, Pashan, India.
| | | | | | | | | |
Collapse
|
9
|
Induction of antibody response against hepatitis E virus (HEV) with recombinant human papillomavirus pseudoviruses expressing truncated HEV capsid proteins in mice. Vaccine 2008; 26:6602-7. [DOI: 10.1016/j.vaccine.2008.09.035] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2008] [Revised: 09/04/2008] [Accepted: 09/15/2008] [Indexed: 11/19/2022]
|
10
|
Deshmukh TM, Lole KS, Tripathy AS, Arankalle VA. Immunogenicity of candidate hepatitis E virus DNA vaccine expressing complete and truncated ORF2 in mice. Vaccine 2007; 25:4350-60. [PMID: 17459540 DOI: 10.1016/j.vaccine.2007.03.040] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2006] [Revised: 03/16/2007] [Accepted: 03/25/2007] [Indexed: 11/24/2022]
Abstract
Hepatitis E virus (HEV) is a major cause of enterically transmitted acute hepatitis of adults in developing nations. Our present studies show that, the complete ORF2 gene (1-660 amino acids, a.a.) coding for capsid protein of HEV as candidate DNA vaccine induced significant specific humoral and cellular immune responses in mice. Gene gun based DNA administration led to higher seroconversion rates and HEV-specific antibody titers as against needle-injection method. The region (458-607a.a.) within ORF2 protein is reported to harbour the predominant neutralization epitope/s (NE) of HEV. The NE DNA also induced HEV-specific immune responses in mice. NE-based DNA-prime-protein boost approach was observed to be superior to NE DNA based approach. Co-administration of plasmid expressing mouse granulocyte macrophage colony stimulating factor (GM-CSF) induced immune response at similar level as that with ORF2/NE plasmid alone. IgG1 was the predominant isotype irrespective of the approach used. HEV-specific antibodies in seroconverted mice sera could bind/neutralize HEV in an in vitro ELISA-based assay. In conclusion, efficacy of ORF2 and NE based DNA/DNA-prime-protein-boost approaches are worth exploring in monkey model.
Collapse
Affiliation(s)
- Tejaswini M Deshmukh
- Hepatitis Division, National Institute of Virology, Microbiological Containment Complex, Sus Road, Pashan, Pune 411021, India
| | | | | | | |
Collapse
|