1
|
Kanda T, Li TC, Takahashi M, Nagashima S, Primadharsini PP, Kunita S, Sasaki-Tanaka R, Inoue J, Tsuchiya A, Nakamoto S, Abe R, Fujiwara K, Yokosuka O, Suzuki R, Ishii K, Yotsuyanagi H, Okamoto H. Recent advances in hepatitis E virus research and the Japanese clinical practice guidelines for hepatitis E virus infection. Hepatol Res 2024; 54:1-30. [PMID: 38874115 DOI: 10.1111/hepr.14062] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/25/2024] [Revised: 04/22/2024] [Accepted: 05/09/2024] [Indexed: 06/15/2024]
Abstract
Acute hepatitis E was considered rare until reports emerged affirming the existence of hepatitis E virus (HEV) genotypes 3 and 4 infections in Japan in the early 2000s. Extensive studies by Japanese researchers have highlighted the pivotal role of pigs and wild animals, such as wild boars and deer, as reservoirs for HEV, linking them to zoonotic infections in Japan. Currently, when hepatitis occurs subsequent to the consumption of undercooked or grilled pork, wild boar meat, or offal (including pig liver and intestines), HEV infection should be considered. Following the approval of anti-HEV immunoglobulin A antibody as a diagnostic tool for hepatitis E by Japan's Health Insurance System in 2011, the annual number of diagnosed cases of HEV infection has surged. Notably, the occurrence of post-transfusion hepatitis E promoted nationwide screening of blood products for HEV using nucleic acid amplification tests since 2020. Furthermore, chronic hepatitis E has been observed in immunosuppressed individuals. Considering the significance of hepatitis E, heightened preventive measures are essential. The Japan Agency for Medical Research and Development Hepatitis A and E viruses (HAV and HEV) Study Group, which includes special virologists and hepatologists, held a virtual meeting on February 17, 2024. Discussions encompassed pathogenesis, transmission routes, diagnosis, complications, severity factors, and ongoing and prospective vaccination or treatments for hepatitis E. Rigorous assessment of referenced studies culminated in the formulation of recommendations, which are detailed within this review. This comprehensive review presents recent advancements in HEV research and Japanese clinical practice guidelines for HEV infection.
Collapse
Affiliation(s)
- Tatsuo Kanda
- Division of Gastroenterology and Hepatology, Department of Medicine, Nihon University School of Medicine, Tokyo, Japan
- Division of Gastroenterology and Hepatology, Uonuma Institute of Community Medicine, Niigata University Medical and Dental Hospital, Minamiuonuma, Japan
- Division of Gastroenterology and Hepatology, Graduate School of Medicine and Dental Sciences, Niigata University, Niigata, Japan
| | - Tian-Cheng Li
- Department of Virology II, National Institute of Infectious Diseases, Tokyo, Japan
| | - Masaharu Takahashi
- Division of Virology, Department of Infection and Immunity, Jichi Medical University School of Medicine, Shimotsuke, Tochigi, Japan
| | - Shigeo Nagashima
- Division of Virology, Department of Infection and Immunity, Jichi Medical University School of Medicine, Shimotsuke, Tochigi, Japan
| | - Putu Prathiwi Primadharsini
- Division of Virology, Department of Infection and Immunity, Jichi Medical University School of Medicine, Shimotsuke, Tochigi, Japan
| | - Satoshi Kunita
- Center for Experimental Medicine, Jichi Medical University School of Medicine, Shimotsuke, Tochigi, Japan
| | - Reina Sasaki-Tanaka
- Division of Gastroenterology and Hepatology, Department of Medicine, Nihon University School of Medicine, Tokyo, Japan
- Division of Gastroenterology and Hepatology, Graduate School of Medicine and Dental Sciences, Niigata University, Niigata, Japan
| | - Jun Inoue
- Division of Gastroenterology, Tohoku University Graduate School of Medicine, Sendai, Japan
| | - Atsunori Tsuchiya
- Division of Gastroenterology and Hepatology, Graduate School of Medicine and Dental Sciences, Niigata University, Niigata, Japan
| | - Shingo Nakamoto
- Department of Gastroenterology, Graduate School of Medicine, Chiba University, Chuo-ku, Chiba, Japan
| | - Ryuzo Abe
- Department of Emergency Medicine, Oita University, Oita, Japan
| | - Keiichi Fujiwara
- Department of Gastroenterology, Graduate School of Medicine, Chiba University, Chuo-ku, Chiba, Japan
| | - Osamu Yokosuka
- Department of Gastroenterology, Graduate School of Medicine, Chiba University, Chuo-ku, Chiba, Japan
| | - Ryosuke Suzuki
- Department of Virology II, National Institute of Infectious Diseases, Tokyo, Japan
| | - Koji Ishii
- Department of Quality Assurance and Radiological Protection, National Institute of Infectious Diseases, Tokyo, Japan
| | - Hiroshi Yotsuyanagi
- Division of Infectious Diseases, Advanced Clinical Research Center, Institute of Medical Science, University of Tokyo, Tokyo, Japan
- Department of Infectious Diseases and Applied Immunology, Hospital of the Institute of Medical Science, University of Tokyo, Tokyo, Japan
| | - Hiroaki Okamoto
- Division of Virology, Department of Infection and Immunity, Jichi Medical University School of Medicine, Shimotsuke, Tochigi, Japan
| |
Collapse
|
2
|
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.
Collapse
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.
| |
Collapse
|
3
|
Lu T, Behloul N, Zhou Y, Baha S, Liu Z, Wei W, Shi RH, Meng J. Hepatitis E Virus Capsid as a Carrier of Exogenous Antigens for the Development of Chimeric Virus-Like Particles. Intervirology 2021; 65:37-48. [PMID: 34695827 DOI: 10.1159/000515719] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2020] [Accepted: 03/08/2021] [Indexed: 11/19/2022] Open
Abstract
INTRODUCTION Virus-like particles (VLPs), self-assembled multiprotein structures, can stimulate robust immune responses due to their structural similarity to native virions that allow the presentation of multiple copies of the target epitopes. Utilizing VLPs as vaccine platforms to present exogenous antigens is a promising and challenging approach in the vaccine development field. This study investigates the potential of the truncated hepatitis E virus (HEV) capsid as a VLP platform to present foreign antigens. METHODS The S and M domains of the HEV capsid protein were selected as the optimal carrier (CaSM). The exogenous antigen Seq8 containing 3 neutralizing epitopes from 3 different foot-and-mouth disease virus (FMDV) strains was linked to the C-terminal of CaSM to construct a chimeric VLP (CaSM-Seq8). The chimeric particles were produced in Escherichia coli, and their morphology, physicochemical properties, antigenicity, and immunogenicity were analyzed. RESULTS Morphological analysis showed that CaSM-Seq8 self-assembled into VLPs similar to CaSM VLPs (∼26 nm in diameter) but smaller than native HEV virions. Further, the thermal stability and the resistance to enzymatic proteolysis of Seq8 were enhanced when it was attached to the CaSM carrier. The antigenicity analysis revealed a more robust reactivity against anti-FMDV antibodies when Seq8 was presented on CaSM particles. Upon injection into mice, FMDV-specific IgGs induced by CaSM-Seq8 appeared earlier, increased faster, and maintained higher levels for a longer time than those induced by Seq8 alone or the inactivated FMDV vaccine. CONCLUSION This study demonstrated the potential of utilizing the truncated HEV capsid as an antigen-presenting platform for the development of chimeric VLP immunogens.
Collapse
Affiliation(s)
- Tianyu Lu
- Department of Gastroenterology, Zhongda Hospital, Southeast University, Nanjing, China
| | - Nouredine Behloul
- College of Basic Medicine, Shanghai University of Medicine & Health Sciences, Shanghai, China
| | - Yi Zhou
- Department of Gastroenterology, Zhongda Hospital, Southeast University, Nanjing, China
| | - Sarra Baha
- Department of Gastroenterology, Zhongda Hospital, Southeast University, Nanjing, China
| | - Zhenzhen Liu
- Department of Gastroenterology, Zhongda Hospital, Southeast University, Nanjing, China
| | - Wenjuan Wei
- Department of Gastroenterology, Zhongda Hospital, Southeast University, Nanjing, China
| | - Rui-Hua Shi
- Department of Gastroenterology, Zhongda Hospital, Southeast University, Nanjing, China
| | - Jihong Meng
- Department of Gastroenterology, Zhongda Hospital, Southeast University, Nanjing, China
| |
Collapse
|
4
|
Zhang N, Zheng T, Chen Y, Zhu H, Qu Y, Zheng H, Liu H, Liu Q. Coxsackievirus B5 virus-like particle vaccine exhibits greater immunogenicity and immunoprotection than its inactivated counterpart in mice. Vaccine 2021; 39:5699-5705. [PMID: 34420787 DOI: 10.1016/j.vaccine.2021.07.095] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2020] [Revised: 07/02/2021] [Accepted: 07/31/2021] [Indexed: 10/20/2022]
Abstract
Coxsackievirus B group 5 (CVB5) represents one of the major pathogens that cause diseases such as hand, foot and mouth disease (HFMD) and aseptic meningitis et al. Currently, no specific drugs and vaccines are available, and a safe and effective CVB5 vaccine is of great value for control of the diseases. In this study, CVB5 P1 precursor and 3CD protease were co-expressed in Sf9 cells by using a baculovirus expression system. The P1 was processed by 3CD and self-assembled into CVB5 virus-like particles (VLPs). VP1 and VP3 capsid proteins of CVB5 could be detected by SDS-PAGE and Western blotting. Transmission electron microscopy revealed that the CVB5 VLPs were spherical particles with a diameter of about 30 nm, mimicking wild-type CVB5 virus. Our study showed that the total IgG and neutralizing antibodies induced by CVB5 VLPs were higher than those induced by inactivated vaccine. More importantly, the CVB5 VLPs conferred full protection to the CVB5-challenged suckling mice via passive immunity while protection efficiency of the inactivated vaccine was only 80%. The CVB5 VLPs vaccine could protect the limb muscles, brain, and heart tissues of suckling mice from CVB5-induced damage. These results demonstrated that the CVB5 VLPs vaccine possessed stronger immunogenicity and provided more robust immunoprotection than the inactivated CVB5 vaccine, suggesting that the CVB5 VLPs promise to be a CVB5 vaccine candidate in future.
Collapse
Affiliation(s)
- Ning Zhang
- Department of Laboratory Medicine, The Second Affiliated Hospital of Guilin Medical University, Guilin, Guangxi, China
| | - Tianpeng Zheng
- Department of Laboratory Medicine, The Second Affiliated Hospital of Guilin Medical University, Guilin, Guangxi, China
| | - Yongbei Chen
- Department of Laboratory Medicine, The Second Affiliated Hospital of Guilin Medical University, Guilin, Guangxi, China
| | - Hanyu Zhu
- College of Biotechnology, Guilin Medical University, Guilin, Guangxi, China
| | - Ying Qu
- Department of Laboratory Medicine, The Second Affiliated Hospital of Guilin Medical University, Guilin, Guangxi, China; College of Pharmacy, Guilin Medical University, Guilin, Guangxi, China
| | - Huanying Zheng
- Guangdong Provincial Institute of Public Health, Guangdong Provincial Center for Disease Control and Prevention, Guangzhou, Guangdong, China
| | - Hongbo Liu
- Department of Laboratory Medicine, The Second Affiliated Hospital of Guilin Medical University, Guilin, Guangxi, China; Guangxi Health Commission Key Laboratory of Glucose and Lipid Metabolism Disorders, Guilin, Guangxi, China.
| | - Qiliang Liu
- Department of Laboratory Medicine, The Second Affiliated Hospital of Guilin Medical University, Guilin, Guangxi, China; College of Biotechnology, Guilin Medical University, Guilin, Guangxi, China.
| |
Collapse
|
5
|
Abstract
The persistence of West Nile virus (WNV) infections throughout the USA since its inception in 1999 and its continuous spread throughout the globe calls for an urgent need of effective treatments and prevention measures. Although the licensing of several WNV vaccines for veterinary use provides a proof of concept, similar efforts on the development of an effective vaccine for humans remain still unsuccessful. Increased understanding of biology and pathogenesis of WNV together with recent technological advancements have raised hope that an effective WNV vaccine may be available in the near future. In addition, rapid progress in the structural and functional characterization of WNV and other flaviviral proteins have provided a solid base for the design and development of several classes of inhibitors as potential WNV therapeutics. Moreover, the therapeutic monoclonal antibodies demonstrate an excellent efficacy against WNV in animal models and represent a promising class of WNV therapeutics. However, there are some challenges as to the design and development of a safe and efficient WNV vaccine or therapeutic. In this chapter, we discuss the current approaches, progress, and challenges toward the development of WNV vaccines, therapeutic antibodies, and antiviral drugs.
Collapse
|
6
|
Stark MC, Baikoghli MA, Lahtinen T, Malola S, Xing L, Nguyen M, Nguyen M, Sikaroudi A, Marjomäki V, Häkkinen H, Cheng RH. Structural characterization of site-modified nanocapsid with monodispersed gold clusters. Sci Rep 2017; 7:17048. [PMID: 29213060 PMCID: PMC5719084 DOI: 10.1038/s41598-017-17171-x] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2017] [Accepted: 11/22/2017] [Indexed: 01/12/2023] Open
Abstract
Hepatitis E Virus-like particles self-assemble in to noninfectious nanocapsids that are resistant to proteolytic/acidic mucosal delivery conditions. Previously, the nanocapsid was engineered to specifically bind and enter breast cancer cells, where successful tumor targeting was demonstrated in animal models. In the present study, the nanocapsid surface was modified with a solvent-exposed cysteine to conjugate monolayer protected gold nanoclusters (AuNC). Unlike commercially available gold nanoparticles, AuNCs monodisperse in water and are composed of a discrete number of gold atoms, forming a crystalline gold core. Au102 pMBA44 (Au102) was an ideal conjugate given its small 2.5 nm size and detectability in cryoEM. Au102 was bound directly to nanocapsid surface cysteines via direct ligand exchange. In addition, Au102 was functionalized with a maleimide linker (Au102_C6MI) for maleimide-thiol conjugation to nanocapsid cysteines. The AuNC-bound nanocapsid constructs were conjugated in various conditions. We found Au102_C6MI to bind nanocapsid more efficiently, while Au102 remained more soluble over time. Nanocapsids conjugated to Au102_C6MI were imaged in cryoEM for single particle reconstruction to localize AuNC position on the nanocapsid surface. We resolved five unique high intensity volumes that formed a ring-shaped density at the 5-fold symmetry center. This finding was further supported by independent rigid modeling.
Collapse
Affiliation(s)
- Marie C Stark
- Department of Biology and Environmental Science, Nanoscience center, University of Jyväskylä, Jyväskylä, FI-40014, Finland
- Department of Molecular and Cellular Biology, University of California, Davis, CA, 95616, USA
| | - Mo A Baikoghli
- Department of Molecular and Cellular Biology, University of California, Davis, CA, 95616, USA
| | - Tanja Lahtinen
- Department of Chemistry, Nanoscience Center, University of Jyväskylä, Jyväskylä, FI-40014, Finland
| | - Sami Malola
- Department of Physics, Nanoscience center, University of Jyväskylä, Jyväskylä, FI-40014, Finland
| | - Li Xing
- Department of Biology and Environmental Science, Nanoscience center, University of Jyväskylä, Jyväskylä, FI-40014, Finland
| | - Michelle Nguyen
- Department of Molecular and Cellular Biology, University of California, Davis, CA, 95616, USA
| | - Marina Nguyen
- Department of Molecular and Cellular Biology, University of California, Davis, CA, 95616, USA
| | - Aria Sikaroudi
- Department of Molecular and Cellular Biology, University of California, Davis, CA, 95616, USA
| | - Varpu Marjomäki
- Department of Biology and Environmental Science, Nanoscience center, University of Jyväskylä, Jyväskylä, FI-40014, Finland
| | - Hannu Häkkinen
- Department of Chemistry, Nanoscience Center, University of Jyväskylä, Jyväskylä, FI-40014, Finland.
- Department of Physics, Nanoscience center, University of Jyväskylä, Jyväskylä, FI-40014, Finland.
| | - R Holland Cheng
- Department of Biology and Environmental Science, Nanoscience center, University of Jyväskylä, Jyväskylä, FI-40014, Finland.
- Department of Molecular and Cellular Biology, University of California, Davis, CA, 95616, USA.
| |
Collapse
|
7
|
Toward Mucosal DNA Delivery: Structural Modularity in Vaccine Platform Design. MICRO AND NANOTECHNOLOGY IN VACCINE DEVELOPMENT 2017. [PMCID: PMC7152392 DOI: 10.1016/b978-0-323-39981-4.00016-6] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Hepatitis E virus is a small, nonenveloped RNA virus that is feco-orally transmitted and causes viral hepatitis in humans. A virus-like particle (VLP) expressed and purified from insect cells shares several properties with the virion but can be manipulated quite extensively through genetic engineering or chemical modification. This has exciting implications for exploiting the VLP as a nanocarrier for foreign epitopes or encapsulated deliverables. By exhaustively studying the structure of the virus, we have been successful in designing and synthesizing chimerized VLPs that either carry foreign epitopes, are capable of encapsulating foreign DNA, or both. Preliminary studies show that these particles provide specific and strong immune responses in mice when orally delivered. To appreciate the full potential of HEV VLPs, we have highlighted various properties of the virus with a strong focus on the VLP structure and the key features that make it suitable for oral delivery.
Collapse
|
8
|
Zhou Y, Zhao C, Tian Y, Xu N, Wang Y. Characteristics and Functions of HEV Proteins. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2016; 948:17-38. [PMID: 27738977 DOI: 10.1007/978-94-024-0942-0_2] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
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' noncoding region, three open reading frames (ORFs), and a 3' noncoding 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 cultured cells 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, and host interaction. 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.
Collapse
Affiliation(s)
- Yan Zhou
- Division of Drug and Cosmetics Inspection, Center for Food and Drug Inspection, China Food and Drug Administration, No.11 Fa Hua Nan Li, Dongcheng District, Beijing, 100061, China
| | - Chenyan Zhao
- Division of HIV/AIDS and Sex-transmitted Virus Vaccines, National Institutes for Food and Drug Control, No. 2 Tiantanxili, Dongcheng District, Beijing, 100050, China
| | - Yabin Tian
- Division of Diagnosis, National Institutes for Food and Drug Control, No. 2 Tiantanxili, Dongcheng District, Beijing, 100050, China
| | - Nan Xu
- Division of HIV/AIDS and Sex-transmitted Virus Vaccines, National Institutes for Food and Drug Control, No. 2 Tiantanxili, Dongcheng District, Beijing, 100050, China
| | - Youchun Wang
- Division of HIV/AIDS and Sex-transmitted Virus Vaccines, National Institutes for Food and Drug Control, No. 2 Tiantanxili, Dongcheng District, Beijing, 100050, China.
| |
Collapse
|
9
|
Qi Y, Fan J, Huang W, Zhao C, Wang Y, Kong FT, Kong W, Jiang C. Expression and characterization of hepatitis E virus-like particles and non-virus-like particles from insect cells. Biotechnol Appl Biochem 2015; 63:362-70. [PMID: 25824972 DOI: 10.1002/bab.1379] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2014] [Accepted: 03/27/2015] [Indexed: 02/05/2023]
Abstract
The hepatitis E virus (HEV) capsid antigen expressed in insect cell has been proposed as a candidate subunit vaccine for the prevention of hepatitis E. However, the expression and purification of HEV virus-like particles (VLPs) from insect cells have not been explored. We aimed to optimize the procedure to obtain HEV VLPs. In this study, two conformations of the HEV capsid proteins were expressed in insect cells, VLPs and non-VLPs, and they were purified separately. The physicochemical properties and the humoral immune responses induced by the two forms were analyzed and compared. We found that HEV VLPs were more immunogenic in mice than HEV non-VLPs. Therefore, we optimized the conditions that yielded high VLPs expression in insect cell cultures and developed an efficient purification method. The results suggest that the distinction and isolation of VLPs from non-VLPs are essential to generate a more immunogenic vaccine.
Collapse
Affiliation(s)
- Ying Qi
- School of Life Science, Jinlin University, Changchun, People's Republic of China.,National Engineering Laboratory for AIDS Vaccine, Jilin University, Changchun, People's Republic of China.,Division of HIV/AIDS and Sexually-Transmitted Virus Vaccines of the National Institutes for Food and. Drug Control, Beijing, People's Republic of China
| | - Jinping Fan
- Division of HIV/AIDS and Sexually-Transmitted Virus Vaccines of the National Institutes for Food and. Drug Control, Beijing, People's Republic of China
| | - Weijin Huang
- Division of HIV/AIDS and Sexually-Transmitted Virus Vaccines of the National Institutes for Food and. Drug Control, Beijing, People's Republic of China
| | - Chenyan Zhao
- Division of HIV/AIDS and Sexually-Transmitted Virus Vaccines of the National Institutes for Food and. Drug Control, Beijing, People's Republic of China
| | - Youchun Wang
- Division of HIV/AIDS and Sexually-Transmitted Virus Vaccines of the National Institutes for Food and. Drug Control, Beijing, People's Republic of China
| | - Franklin T Kong
- Ann Arbor Pioneer High School, 601 West Stadium Blvd, Ann Arbor
| | - Wei Kong
- School of Life Science, Jinlin University, Changchun, People's Republic of China.,National Engineering Laboratory for AIDS Vaccine, Jilin University, Changchun, People's Republic of China
| | - Chunlai Jiang
- School of Life Science, Jinlin University, Changchun, People's Republic of China.,National Engineering Laboratory for AIDS Vaccine, Jilin University, Changchun, People's Republic of China
| |
Collapse
|
10
|
Abstract
INTRODUCTION Hepatitis E virus (HEV) is one of the most common causes of acute viral hepatitis in the world with an estimated 20 million infections per year. Although the mortality rate is < 1% among the general population, pregnant women can have a fatality rate of up to 30%. Additionally, chronic hepatitis E has increasingly become a significant clinical problem in immunocompromised individuals. Effective antivirals against HEV are needed. AREAS COVERED This review article addresses the current state of knowledge of HEV infections with regard to animal and cell culture model systems that are important for antiviral discovery and testing, our current understanding of the molecular mechanisms of virus replication, our understanding of how each viral protein functions, and areas that can potentially be exploited as therapeutic targets. EXPERT OPINION Lack of an efficient cell culture system for HEV propagation, the limited knowledge of HEV lifecycle, and the inherent self-limiting infection within the normal populace make the development of new therapeutic agents against HEV challenging. There are many promising therapeutic targets, and the tools for identifying and testing potential antivirals are rapidly evolving. The development of effective therapeutics against HEV in immunocompromised and pregnant patient populations is warranted.
Collapse
Affiliation(s)
- Scott P Kenney
- Virginia Polytechnic Institute and State University (Virginia Tech), College of Veterinary Medicine, Center for Molecular Medicine and Infectious Diseases, Department of Biomedical Sciences and Pathobiology , CRC-Integrated Life Sciences Building (0913), 1981 Kraft Drive, Blacksburg, VA 24061-0913 , USA +1 540 231 6912 ; +1 540 231 3414 ;
| | | |
Collapse
|
11
|
A novel platform for virus-like particle-display of flaviviral envelope domain III: induction of Dengue and West Nile virus neutralizing antibodies. Virol J 2013; 10:129. [PMID: 23617954 PMCID: PMC3668303 DOI: 10.1186/1743-422x-10-129] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2012] [Accepted: 03/26/2013] [Indexed: 11/10/2022] Open
Abstract
CD16-RIgE is a chimeric human membrane glycoprotein consisting of the CD16 ectodomain fused to the transmembrane domain and cytoplasmic tail of the gamma chain of the high affinity receptor of IgE (RIgE). Coexpression of CD16-RIgE and HIV-1 Pr55Gag polyprotein precursor (Pr55GagHIV) in insect cells resulted in the incorporation of CD16-RIgE glycoprotein into the envelope of extracellular virus-like particles (VLPs), a phenomenon known as pseudotyping. Taking advantage of this property, we replaced the CD16 ectodomain of CD16-RIgE by the envelope glycoprotein domain III (DIII) of dengue virus serotype 1 (DENV1) or West Nile virus Kunjin (WNVKun). The two resulting chimeric proteins, DIII-DENV1-RIgE and DIII-WNVKun-RIgE, were addressed to the plasma membrane, exposed at the surface of human and insect cells, and incorporated into extracellular VLPs when coexpressed with Pr55GagHIV in insect cells. The DIII domains were accessible at the surface of retroviral VLPs, as shown by their reactivity with specific antibodies, and notably antibodies from patient sera. The DIII-RIgE proteins were found to be incorporated in VLPs made of SIV, MLV, or chimeric MLV-HIV Gag precursors, indicating that DIII-RIgE could pseudotype a wide variety of retroviral VLPs. VLP-displayed DIII were capable of inducing specific neutralizing antibodies against DENV and WNV in mice. Although the neutralization response was modest, our data confirmed the capability of DIII to induce a flavivirus neutralization response, and suggested that our VLP-displayed CD16-RIgE-based platform could be developed as a vaccine vector against different flaviviruses and other viral pathogens.
Collapse
|
12
|
Cao D, Meng XJ. Molecular biology and replication of hepatitis E virus. Emerg Microbes Infect 2012; 1:e17. [PMID: 26038426 PMCID: PMC3630916 DOI: 10.1038/emi.2012.7] [Citation(s) in RCA: 108] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2011] [Revised: 03/21/2012] [Accepted: 04/08/2012] [Indexed: 02/07/2023]
Abstract
Hepatitis E virus (HEV), a single-stranded, positive-sense RNA virus, is responsible for acute hepatitis E epidemics in many developing countries, and the virus is also endemic in some industrialized countries. Hepatitis E is a recognized zoonotic disease, and several animal species, including pigs, are potential reservoirs for HEV. The genome of HEV contains three open reading frames (ORFs). ORF1 encodes the nonstructural proteins, ORF2 encodes the capsid protein, and ORF3 encodes a small multifunctional protein. The ORF2 and ORF3 proteins are translated from a single, bicistronic mRNA. The coding sequences for these two ORFs overlap each other, but neither overlaps with ORF1. Whereas the mechanisms underlying HEV replication are poorly understood, the construction of infectious viral clones, the identification of cell lines that support HEV replication, and the development of small animal models have allowed for more detailed study of the virus. As result of these advances, recently, our understanding of viral entry, genomic replication and viral egress has improved. Furthermore, the determination of the T=1 and T=3 structure of HEV virus-like particles has furthered our understanding of the replication of HEV. This article reviews the latest developments in the molecular biology of HEV with an emphasis on the genomic organization, the expression and function of genes, and the structure and replication of HEV.
Collapse
Affiliation(s)
- Dianjun Cao
- Center for Molecular Medicine and Infectious Diseases, Department of Biomedical Sciences and Pathobiology, Virginia Polytechnic Institute and State University (Virginia Tech) , Blacksburg, VA 24061-0913, USA
| | - Xiang-Jin Meng
- Center for Molecular Medicine and Infectious Diseases, Department of Biomedical Sciences and Pathobiology, Virginia Polytechnic Institute and State University (Virginia Tech) , Blacksburg, VA 24061-0913, USA
| |
Collapse
|
13
|
Okamoto H. Efficient cell culture systems for hepatitis E virus strains in feces and circulating blood. Rev Med Virol 2011; 21:18-31. [PMID: 21294213 DOI: 10.1002/rmv.678] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Attempts have been made to propagate hepatitis E virus (HEV) in primary hepatocyte culture and various other cultured cells. However, the replication ability of HEV recovered from culture media remains extremely low. Recently, efficient culture systems have been established in PLC/PRF/5 (hepatocellular carcinoma) and A549 (lung cancer) cell lines for HEV strains of genotypes 3 and 4 in our laboratory. They originated in fecal extracts from patients containing HEV RNA in extremely high-titers (10(7) copies/ml), and named the JE03-1760F (genotype 3) and HE-JF5/15F (genotype 4) strains, respectively. HEV RNA in culture supernatants reached 10(8) copies/ml in titer, and were transmitted successively through many passages. An infectious HEV cDNA clone (pJE03-1760F/wt) was constructed that has replication activity comparable to that of the wild-type JE03-1760F in feces. The ORF3 protein is indispensable for shedding HEV particles from cells in the reverse genetics system. HEV recovered from culture media, as well as circulating HEV, possess ORF3 proteins on the surface and are covered with cellular membranes, and therefore, ORF2 epitopes are buried in these particles. In contrast, HEV excreted into feces are naked nucleocapsids without a lipid layer or surface expression of the ORF3 protein. HEV in sera of patients with acute hepatitis E can infect and replicate in PLC/PRF/5 and A549 cells, with efficiency comparable to the circulating HEV RNA levels. High-efficiency cell culture systems for infectious viruses, thus developed, are expected to open up a new era and resolve many mysteries in the epidemiology, molecular biology, and treatment of HEV.
Collapse
Affiliation(s)
- Hiroaki Okamoto
- Department of Infection and Immunity, Jichi Medical University School of Medicine, Shimotsuke-Shi, Tochigi, Japan.
| |
Collapse
|
14
|
Xing L, Li TC, Mayazaki N, Simon MN, Wall JS, Moore M, Wang CY, Takeda N, Wakita T, Miyamura T, Cheng RH. Structure of hepatitis E virion-sized particle reveals an RNA-dependent viral assembly pathway. J Biol Chem 2010; 285:33175-33183. [PMID: 20720013 DOI: 10.1074/jbc.m110.106336] [Citation(s) in RCA: 123] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
Hepatitis E virus (HEV) induces acute hepatitis in humans with a high fatality rate in pregnant women. There is a need for anti-HEV research to understand the assembly process of HEV native capsid. Here, we produced a large virion-sized and a small T=1 capsid by expressing the HEV capsid protein in insect cells with and without the N-terminal 111 residues, respectively, for comparative structural analysis. The virion-sized capsid demonstrates a T=3 icosahedral lattice and contains RNA fragment in contrast to the RNA-free T=1 capsid. However, both capsids shared common decameric organization. The in vitro assembly further demonstrated that HEV capsid protein had the intrinsic ability to form decameric intermediate. Our data suggest that RNA binding is the extrinsic factor essential for the assembly of HEV native capsids.
Collapse
Affiliation(s)
- Li Xing
- From the Department of Molecular and Cellular Biology, University of California, Davis, California 95616; Structural Virology Section, Karolinska Institute, Huddinge University Hospital, SE-14186 Stockholm, Sweden
| | - Tian-Cheng Li
- Department of Virology II, National Institute of Infectious Diseases, Tokyo 208-0011, Japan
| | - Naoyuki Mayazaki
- From the Department of Molecular and Cellular Biology, University of California, Davis, California 95616; Structural Virology Section, Karolinska Institute, Huddinge University Hospital, SE-14186 Stockholm, Sweden
| | - Martha N Simon
- Biology Department, Brookhaven National Laboratory, Upton, New York 11973-5000
| | - Joseph S Wall
- Biology Department, Brookhaven National Laboratory, Upton, New York 11973-5000
| | - Mary Moore
- From the Department of Molecular and Cellular Biology, University of California, Davis, California 95616
| | - Che-Yen Wang
- From the Department of Molecular and Cellular Biology, University of California, Davis, California 95616
| | - Naokazu Takeda
- Department of Virology II, National Institute of Infectious Diseases, Tokyo 208-0011, Japan
| | - Takaji Wakita
- Department of Virology II, National Institute of Infectious Diseases, Tokyo 208-0011, Japan
| | - Tatsuo Miyamura
- Department of Virology II, National Institute of Infectious Diseases, Tokyo 208-0011, Japan
| | - R Holland Cheng
- From the Department of Molecular and Cellular Biology, University of California, Davis, California 95616.
| |
Collapse
|
15
|
Release of genotype 1 hepatitis E virus from cultured hepatoma and polarized intestinal cells depends on open reading frame 3 protein and requires an intact PXXP motif. J Virol 2010; 84:9059-69. [PMID: 20610720 DOI: 10.1128/jvi.00593-10] [Citation(s) in RCA: 133] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
Hepatitis E virus genotype 1 strain Sar55 replicated in subcloned Caco-2 intestinal cells and Huh7 hepatoma cells that had been transfected with in vitro transcribed viral genomes, and hepatitis E virions were released into the culture medium of both cell lines. Virus egress from cells depended on open reading frame 3 (ORF3) protein, and a proline-rich sequence in ORF3 was important for egress from cultured cells and for infection of macaques. Both intracellular ORF3 protein accumulation and virus release occurred at the apical membrane of polarized Caco-2 cells. ORF3 protein and lipids were intimately associated with virus particles produced in either cell line; ORF2 epitopes were masked in these particles and could not be immunoprecipitated with anti-ORF2.
Collapse
|
16
|
Abstract
Hepatitis E virus (HEV), the causative agent of hepatitis E, belongs to the family Hepeviridae. At least four major genotypes of HEV have been recognized: genotypes 1 and 2 are restricted to humans and associated with epidemics in developing countries, whereas genotypes 3 and 4 are zoonotic and infect humans and several other animals in both developing and industrialized countries. Besides humans, strains of HEV have been genetically identified from swine, chickens, sika deer, mongeese, and rabbits. The genome of HEV consists of three open reading frames (ORFs): ORF1 codes for nonstructural proteins, ORF2 codes for capsid protein, and ORF3 codes for a small multifunctional protein. The ORF2 and ORF3 proteins are translated from a single bicistronic mRNA and overlap each other but neither overlaps ORF1. The recent determination of the 3D crystal structure of the HEV capsid protein should facilitate the development of vaccines and antivirals. The identification and characterization of animal strains of HEV from pigs and chickens and the demonstrated ability of cross-species infection by swine HEV raise public health concerns for zoonosis. Accumulating evidence indicated that hepatitis E is a zoonotic disease and pigs and more likely other animal species are reservoirs for HEV. This article provides an overview of the recent advances in hepatitis E and its causative agent, including nomenclature and genomic organization, gene expression and functions, 3D structure of the virions, changing perspectives on higher mortality during pregnancy and chronic hepatitis E, animal reservoirs, zoonotic risk, food safety, and novel animal models.
Collapse
Affiliation(s)
- X J Meng
- Department of Biomedical Sciences and Pathobiology, Center for Molecular Medicine and Infectious Diseases, Virginia Polytechnic Institute and State University, Blacksburg, VA, USA.
| |
Collapse
|
17
|
Abstract
PURPOSE OF REVIEW Hepatitis E is an emerging infectious disease. This review will focus on recent advances in the zoonotic transmission, global distribution and control of hepatitis E. RECENT FINDINGS Hepatitis E virus infection is known to cause waterborne epidemics and sporadic infections in developing countries. Recently, there have been several reports on zoonotic foodborne autochthonous infections of hepatitis E in developed countries. Hepatitis E typically causes self-limited acute infection. Recent reports have documented hepatitis E virus causing chronic hepatitis and cirrhosis in patients after solid organ transplantation. High incidence and severity of hepatitis E in pregnant women have been re-confirmed. The reason for high mortality in pregnant women remains ill understood. A recombinant hepatitis E vaccine has been evaluated in a phase 2, randomized, placebo-controlled trial in Nepal and was found to be well tolerated and efficacious. SUMMARY There has been considerable advance in understanding the epidemiology of hepatitis E virus infections in western countries. The occurrence of chronic hepatitis in organ transplant recipients opens a new chapter in hepatitis E epidemiology. The report on an efficacious and well tolerated recombinant vaccine gives hope for control of the disease in the near future.
Collapse
|