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Liu J, Wang Z, Ma J, Ji S, Huo Y. Identification of a norovirus GII-specific antigenic epitope. Arch Virol 2024; 169:131. [PMID: 38819530 DOI: 10.1007/s00705-024-06060-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2024] [Accepted: 04/17/2024] [Indexed: 06/01/2024]
Abstract
Noroviruses (NoVs) are the chief cause of acute viral gastroenteritis worldwide. By employing the major capsid protein VP1 of a GII.6 NoV strain as an immunogen, we generated two monoclonal antibodies (mAbs) with wide-spectrum binding activities against NoV genogroup II (GII) VP1 proteins. One mAb (10G7) could bind to native and denatured GII-specific VP1 proteins. The other mAb (10F2) could bind to all tested native GII VP1 proteins, but not to denatured GII.3, GII.4, GII.7, or GII.17 VP1 proteins. Using GII.6/GII.4 fusion proteins, the mAb 10F2 binding region was confirmed to be located in the C-terminal P1 domain. An enzyme-linked immunosorbent assay based on peptides covering the P domain did not detect any binding. Using a panel of VP1 proteins with swapped regions, deletions, and mutations, the mAb 10F2 binding region was determined to be located between residues 496 and 513. However, the residue(s) responsible for its varied binding affinity for different denatured GII VP1 proteins remain to be identified. In summary, two NoV GII-specific cross-reactive mAbs were generated, and their binding regions were determined. Our results might facilitate the detection and immunogenic study of NoVs.
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Affiliation(s)
- Jinjin Liu
- Affiliated Infectious Diseases Hospital of Zhengzhou University, Henan Infectious Diseases Hospital, The Sixth People's Hospital of Zhengzhou, Center for Translational Medicine, Zhengzhou, China
| | - Zhanzheng Wang
- Zhengzhou Cell to Antibody & antigen Biotechnology, Zhengzhou, China
| | - Jie Ma
- Affiliated Infectious Diseases Hospital of Zhengzhou University, Henan Infectious Diseases Hospital, The Sixth People's Hospital of Zhengzhou, Center for Translational Medicine, Zhengzhou, China
| | - Shaoping Ji
- Medical college, Cell Signal Transduction Laboratory, Henan University, Henan, China
| | - Yuqi Huo
- Affiliated Infectious Diseases Hospital of Zhengzhou University, Henan Infectious Diseases Hospital, The Sixth People's Hospital of Zhengzhou, Center for Translational Medicine, Zhengzhou, China.
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2
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Eftekhari M, Kachooei A, Jalilvand S, Latifi T, Habib Z, Ataei-Pirkoohi A, Marashi SM, Shoja Z. The predominance of recombinant Norovirus GII.4Sydney[P16] strains in children less than 5 years of age with acute gastroenteritis in Tehran, Iran, 2021-2022. Virus Res 2023; 334:199172. [PMID: 37459917 PMCID: PMC10388203 DOI: 10.1016/j.virusres.2023.199172] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2023] [Revised: 07/12/2023] [Accepted: 07/13/2023] [Indexed: 07/28/2023]
Abstract
The present study was aimed to both detect emerging noroviruses and investigate RdRp and VP1-based dual typing of circulating noroviruses in hospitalized children less than 5 years of age with acute gastroenteritis (AGE) in Iran. For this purpose, a total of 200 stool specimens were screened during 2021-2022 by real-time RT-PCR for genogroup I and II (GI and GII) and dual-typed by sequence analysis of PCR products, using a web-based norovirus Typing Tool and phylogenetic analysis. The GI and GII noroviruses were detected in 20% of 200 specimens. The GII.4 norovirus was found to be the most common VP1 genotype (53%) followed by GII.8 (32%), GII.7 (6%), GII.17 (6%), and GII.3 (3%). The GII.P16 norovirus was also found as the predominant RdRp type (53%) followed by GII.P8 (32%), GII.P7 (6%), GII.P17 (6%), and GII.P31 (3%). To our knowledge, this is the first report that highlights the dominancy of recombinant norovirus GII.4Sydney[P16] and newly emerging of norovirus GII.8 [P8], GII.17 [P17] and GII.3 [P16] in Iran. These findings further indicate inter-genotype recombinant strains of noroviruses.
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Affiliation(s)
- Mahtab Eftekhari
- Department of Virology, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran
| | - Atefeh Kachooei
- Department of Virology, School of Medicine, Iran University of Medical Sciences, Tehran, Iran; Department of Virology, Pasteur Institute of Iran, Tehran, Iran
| | - Somayeh Jalilvand
- Department of Virology, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran
| | - Tayebeh Latifi
- Department of Virology, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran; Department of Virology, Pasteur Institute of Iran, Tehran, Iran
| | - Zahra Habib
- Department of Virology, School of Medicine, Iran University of Medical Sciences, Tehran, Iran
| | - Angila Ataei-Pirkoohi
- Department of Virology, School of Medicine, Iran University of Medical Sciences, Tehran, Iran
| | - Sayed Mahdi Marashi
- Department of Virology, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran
| | - Zabihollah Shoja
- Department of Virology, Pasteur Institute of Iran, Tehran, Iran; Research Center for Emerging and Reemerging Infectious Diseases, Pasteur Institute of Iran, Tehran, Iran.
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3
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Kim M, Foster JC, Moore MD, Chen M. Improving Single-Molecule Antibody Detection Selectivity through Optimization of Peptide Epitope Presentation in OmpG Nanopore. ACS Sens 2023. [PMID: 37379512 DOI: 10.1021/acssensors.3c00528] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/30/2023]
Abstract
Outer membrane protein G (OmpG) is a monomeric porin found in Escherichia coli, which possesses seven flexible loops. OmpG has been engineered as a nanopore sensor, where its loops can host affinity epitopes for selective detection of biological molecules. In this study, we investigated various loop positions to incorporate a FLAG peptide antigen epitope in the most flexible loop 6 and tested the efficacy and sensitivity of these nanopore constructs in antibody detection. We observed an OmpG construct containing inserted FLAG sequence, which exhibited strong interaction with anti-FLAG antibodies in flow cytometry; however, it could not translate molecule interactions into a readable signal in current recordings. Further optimization of the peptide presentation strategy by replacing specific sections of loop 6 sequences with the FLAG tag created a construct capable of generating unique and distinct signals when interacting with various monoclonal or polyclonal anti-FLAG clones IgG antibodies in the mixture. The peptide display scheme demonstrated in this study can be generalized for the engineering of OmpG sensors, which can be used for screening and validating positive clones during antibody development, as well as for real-time quality control of cell cultures in monoclonal antibody production.
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Affiliation(s)
- Minji Kim
- Department of Food Science, University of Massachusetts Amherst, Amherst, Massachusetts 01003, United States
| | - Joshua C Foster
- Molecular and Cellular Biology Program, University of Massachusetts Amherst, Amherst, Massachusetts 01003, United States
| | - Matthew D Moore
- Department of Food Science, University of Massachusetts Amherst, Amherst, Massachusetts 01003, United States
- Molecular and Cellular Biology Program, University of Massachusetts Amherst, Amherst, Massachusetts 01003, United States
| | - Min Chen
- Molecular and Cellular Biology Program, University of Massachusetts Amherst, Amherst, Massachusetts 01003, United States
- Department of Chemistry, University of Massachusetts Amherst, Amherst, Massachusetts 01003, United States
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4
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Takano T, Ryu M, Doki T, Kusuhara H. Immunodominant B-Cell Linear Epitope on the VP1 P Domain of a Feline Norovirus Cat Model. Pathogens 2022; 11:pathogens11070731. [PMID: 35889977 PMCID: PMC9316177 DOI: 10.3390/pathogens11070731] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2022] [Revised: 06/21/2022] [Accepted: 06/24/2022] [Indexed: 11/21/2022] Open
Abstract
Norovirus (NoV) infection remains a major public health concern worldwide. Appropriate animal models are essential for the development of effective NoV vaccines. We previously established the feline NoV (FNoV)-cat model as a surrogate animal model for human NoV infection. In the present study, we analyzed the B-cell linear epitope in the P domain of FNoV to confirm the basic immunological features of the FNoV-cat model. B-cell linear epitopes were present in the P2 subdomain. We compared antibody levels to peptides containing the B-cell linear epitope (P-10) in three FNoV-infected cats with time-course changes in viral load and symptom scoring. After FNoV infection, viral shedding and clinical symptoms were shown to improve by elevated levels of antibodies against P-10 in the plasma. This report provides important information for understanding NoV infections in humans and cats.
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Affiliation(s)
- Tomomi Takano
- Laboratory of Veterinary Infectious Disease, School of Veterinary Medicine, Kitasato University, Towada 34-8628, Japan; (M.R.); (T.D.)
- Correspondence:
| | - Mizuki Ryu
- Laboratory of Veterinary Infectious Disease, School of Veterinary Medicine, Kitasato University, Towada 34-8628, Japan; (M.R.); (T.D.)
| | - Tomoyoshi Doki
- Laboratory of Veterinary Infectious Disease, School of Veterinary Medicine, Kitasato University, Towada 34-8628, Japan; (M.R.); (T.D.)
| | - Hajime Kusuhara
- Health and Environment Research Institute, Yokkaichi 512-1211, Japan;
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5
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Razafimahefa RM, Ludwig-Begall LF, Diallo MA, Dewals BG, Vanderplasschen A, Nivelles O, Deketelaere C, Mauroy A, Thiry E. Development of a Specific Anti-capsid Antibody- and Magnetic Bead-Based Immunoassay to Detect Human Norovirus Particles in Stool Samples and Spiked Mussels via Flow Cytometry. FOOD AND ENVIRONMENTAL VIROLOGY 2021; 13:493-506. [PMID: 34363588 DOI: 10.1007/s12560-021-09494-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/27/2021] [Accepted: 07/28/2021] [Indexed: 06/13/2023]
Abstract
Human noroviruses impose a considerable health burden globally. Here, a flow cytometry approach designed for their detection in biological waste and food samples was developed using antibody-coated magnetic beads. Antipeptide antibodies against murine norovirus and various human norovirus genotypes were generated for capture and coated onto magnetic beads. A flow cytometry assay was then implemented to detect bead-bound human norovirus GI.3 in patient stool samples and in norovirus-spiked mussel digestive tissues. The detection limit for stool samples was 105 gc/mL, thus bettering detection limits of commercially available norovirus diagnosis quick kits of 100-fold; the detection limit in spiked mussels however was ten-fold higher than in stool samples. Further assays showed a decrease in fluorescence intensity for heat- or UV-inactivated virus particles. Overall, we demonstrate the application of a flow cytometry approach for direct detection of small non-enveloped virus particles such as noroviruses. An adaptation of the technology to routine diagnostics has the potential to contribute a rapid and sensitive tool to norovirus outbreak investigations. Further improvements to the method, notably decreasing the detection limit of the approach, may allow the analysis of naturally contaminated food and environmental samples.
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Affiliation(s)
- Ravo M Razafimahefa
- Veterinary Virology and Animal Viral Diseases, Department of Infectious and Parasitic Diseases, Faculty of Veterinary Medicine, FARAH Research Centre, Liège University, B43b, Quartier Vallée 2, Avenue de Cureghem, 10, B-4000, Liège, Belgium
| | - Louisa F Ludwig-Begall
- Veterinary Virology and Animal Viral Diseases, Department of Infectious and Parasitic Diseases, Faculty of Veterinary Medicine, FARAH Research Centre, Liège University, B43b, Quartier Vallée 2, Avenue de Cureghem, 10, B-4000, Liège, Belgium
| | - Mamadou Amadou Diallo
- Immunology-Vaccinology, Department of Infectious and Parasitic Diseases, Faculty of Veterinary Medicine, FARAH Research Centre, Liège University, B43b, Quartier Vallée 2, Avenue de Cureghem, 10, B-4000, Liège, Belgium
| | - Benjamin G Dewals
- Immunology-Vaccinology, Department of Infectious and Parasitic Diseases, Faculty of Veterinary Medicine, FARAH Research Centre, Liège University, B43b, Quartier Vallée 2, Avenue de Cureghem, 10, B-4000, Liège, Belgium
| | - Alain Vanderplasschen
- Immunology-Vaccinology, Department of Infectious and Parasitic Diseases, Faculty of Veterinary Medicine, FARAH Research Centre, Liège University, B43b, Quartier Vallée 2, Avenue de Cureghem, 10, B-4000, Liège, Belgium
| | - Olivier Nivelles
- Immunology-Vaccinology, Department of Infectious and Parasitic Diseases, Faculty of Veterinary Medicine, FARAH Research Centre, Liège University, B43b, Quartier Vallée 2, Avenue de Cureghem, 10, B-4000, Liège, Belgium
| | - Caroline Deketelaere
- Immunology-Vaccinology, Department of Infectious and Parasitic Diseases, Faculty of Veterinary Medicine, FARAH Research Centre, Liège University, B43b, Quartier Vallée 2, Avenue de Cureghem, 10, B-4000, Liège, Belgium
| | - Axel Mauroy
- Staff Direction for Risk Assessment, Control Policy, Federal Agency for the Safety of the Food Chain, Bld du Jardin Botanique 55, B-1000, Brussels, Belgium
| | - Etienne Thiry
- Veterinary Virology and Animal Viral Diseases, Department of Infectious and Parasitic Diseases, Faculty of Veterinary Medicine, FARAH Research Centre, Liège University, B43b, Quartier Vallée 2, Avenue de Cureghem, 10, B-4000, Liège, Belgium.
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6
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Boonyakida J, Utomo DIS, Soma FN, Park EY. Two-step purification of tag-free norovirus-like particles from silkworm larvae (Bombyx mori). Protein Expr Purif 2021; 190:106010. [PMID: 34737040 DOI: 10.1016/j.pep.2021.106010] [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: 09/30/2021] [Revised: 10/29/2021] [Accepted: 10/31/2021] [Indexed: 10/19/2022]
Abstract
Recombinantly expressed VP1 of norovirus self-assembled and formed norovirus-like particles (NoV-LPs). This native VP1 was expressed using the Bombyx mori nucleopolyhedrovirus (BmNPV) expression system in silkworm larva. NoV-LPs were collected from silkworm fat body lysate by density gradient centrifugation. To improve the purity of the NoV-LP, the proteins were further purified using immobilized metal affinity chromatography based on the surface exposed side chain of histidine residues. The additional purification led to a highly purified virus-like particle (VLP). The morphology and size of the purified VLPs were examined using a transmission electron microscope, and dynamic light scattering revealed a monodispersed spherical morphology with a diameter of 34 nm. The purified product had a purity of >90% with a recovery yield of 48.7% (equivalent to 930 μg) from crude lysate, obtained from seven silkworm larvae. In addition, the purified VLP could be recognized by antibodies against GII norovirus in sandwich enzyme-linked immunosorbent assay, which indicated that the silkworm-derived VLP is biologically functional as a NoV-LP in its native state, is structurally correct, and exerts its biological function. Our results suggest that the silkworm-derived NoV-LP may be useful for subsequent applications, such as in a vaccine platform. Moreover, the silkworm-based expression system is known for its robustness, facile up-scalability, and relatively low expense compared to insect cell systems.
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Affiliation(s)
- Jirayu Boonyakida
- Department of Bioscience, Graduate School of Science and Technology, Shizuoka University, 836 Ohya, Suruga-ku, Shizuoka, 422-8529, Japan
| | - Doddy Irawan Setyo Utomo
- Department of Bioscience, Graduate School of Science and Technology, Shizuoka University, 836 Ohya, Suruga-ku, Shizuoka, 422-8529, Japan
| | - Fahmida Nasrin Soma
- Research Institute of Green Science and Technology, Shizuoka University, 836 Ohya, Suruga-ku, Shizuoka, 422-8529, Japan
| | - Enoch Y Park
- Department of Bioscience, Graduate School of Science and Technology, Shizuoka University, 836 Ohya, Suruga-ku, Shizuoka, 422-8529, Japan; Research Institute of Green Science and Technology, Shizuoka University, 836 Ohya, Suruga-ku, Shizuoka, 422-8529, Japan.
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7
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Faircloth J, Moore MD, Stoufer S, Kim M, Jaykus LA. Generation of Nucleic Acid Aptamer Candidates against a Novel Calicivirus Protein Target. Viruses 2021; 13:v13091716. [PMID: 34578297 PMCID: PMC8473235 DOI: 10.3390/v13091716] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2021] [Revised: 08/24/2021] [Accepted: 08/27/2021] [Indexed: 11/16/2022] Open
Abstract
Human norovirus is the leading cause of foodborne illness globally. One of the challenges in detecting noroviruses is the identification of a completely broadly reactive ligand; however, all detection ligands generated to date target the viral capsid, the outermost of which is the most variable region of the genome. The VPg is a protein covalently linked to the viral genome that is necessary for replication but hitherto remains underexplored as a target for detection or therapeutics. The purpose of this work was to generate nucleic acid aptamers against human norovirus (Norwalk) and cultivable surrogate (Tulane) VPgs for future use in detection and therapeutics. Eight rounds of positive-SELEX and two rounds of counter-SELEX were performed. Five and eight unique aptamer sequences were identified for Norwalk and Tulane VPg, respectively, all of which were predicted to be stable (∆G < −5.0) and one of which occurred in both pools. All candidates displayed binding to both Tulane and Norwalk VPg (positive:negative > 5.0), and all but two of the candidates displayed very strong binding (positive:negative > 10.0), significantly higher than binding to the negative control protein (p < 0.05). Overall, this work reports a number of aptamer candidates found to be broadly reactive and specific for in vitro-expressed VPgs across genus that could be used for future application in detection or therapeutics. Future work characterizing binding of the aptamer candidates against native VPgs and in therapeutic applications is needed to further evaluate their application.
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Affiliation(s)
- Jeremy Faircloth
- Department of Food, Bioprocessing, and Nutrition Sciences, North Carolina State University, Raleigh, NC 27695, USA; (J.F.); (L.-A.J.)
| | - Matthew D. Moore
- Department of Food, Bioprocessing, and Nutrition Sciences, North Carolina State University, Raleigh, NC 27695, USA; (J.F.); (L.-A.J.)
- Department of Food Science, University of Massachusetts, Amherst, MA 01003, USA; (S.S.); (M.K.)
- Correspondence: ; Tel.: +1-413-545-1019
| | - Sloane Stoufer
- Department of Food Science, University of Massachusetts, Amherst, MA 01003, USA; (S.S.); (M.K.)
| | - Minji Kim
- Department of Food Science, University of Massachusetts, Amherst, MA 01003, USA; (S.S.); (M.K.)
| | - Lee-Ann Jaykus
- Department of Food, Bioprocessing, and Nutrition Sciences, North Carolina State University, Raleigh, NC 27695, USA; (J.F.); (L.-A.J.)
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8
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Broadly cross-reactive human antibodies that inhibit genogroup I and II noroviruses. Nat Commun 2021; 12:4320. [PMID: 34262046 PMCID: PMC8280134 DOI: 10.1038/s41467-021-24649-w] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2020] [Accepted: 06/29/2021] [Indexed: 12/14/2022] Open
Abstract
The rational development of norovirus vaccine candidates requires a deep understanding of the antigenic diversity and mechanisms of neutralization of the virus. Here, we isolate and characterize a panel of broadly cross-reactive naturally occurring human monoclonal IgMs, IgAs and IgGs reactive with human norovirus (HuNoV) genogroup I or II (GI or GII). We note three binding patterns and identify monoclonal antibodies (mAbs) that neutralize at least one GI or GII HuNoV strain when using a histo-blood group antigen (HBGA) blocking assay. The HBGA blocking assay and a virus neutralization assay using human intestinal enteroids reveal that the GII-specific mAb NORO-320, mediates HBGA blocking and neutralization of multiple GII genotypes. The Fab form of NORO-320 neutralizes GII.4 infection more potently than the mAb, however, does not block HBGA binding. The crystal structure of NORO-320 Fab in complex with GII.4 P-domain shows that the antibody recognizes a highly conserved region in the P-domain distant from the HBGA binding site. Dynamic light scattering analysis of GII.4 virus-like particles with mAb NORO-320 shows severe aggregation, suggesting neutralization is by steric hindrance caused by multivalent cross-linking. Aggregation was not observed with the Fab form of NORO-320, suggesting that this clone also has additional inhibitory features. Noroviruses can cause gastroenteritis and there is currently no licensed vaccine or specific treatment available. Here, the authors isolate human monoclonal antibodies and characterize one antibody (NORO-320) with broad reactivity to genogroup I and II noroviruses.
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Pattekar A, Mayer LS, Lau CW, Liu C, Palko O, Bewtra M, Consortium HPAP, Lindesmith LC, Brewer-Jensen PD, Baric RS, Betts MR, Naji A, Wherry EJ, Tomov VT. Norovirus-Specific CD8 + T Cell Responses in Human Blood and Tissues. Cell Mol Gastroenterol Hepatol 2021; 11:1267-1289. [PMID: 33444817 PMCID: PMC8010716 DOI: 10.1016/j.jcmgh.2020.12.012] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/18/2020] [Revised: 11/26/2020] [Accepted: 12/15/2020] [Indexed: 02/08/2023]
Abstract
BACKGROUND & AIMS Noroviruses (NoVs) are the leading cause of acute gastroenteritis worldwide and are associated with significant morbidity and mortality. Moreover, an asymptomatic carrier state can persist following acute infection, promoting NoV spread and evolution. Thus, defining immune correlates of NoV protection and persistence is needed to guide the development of future vaccines and limit viral spread. Whereas antibody responses following NoV infection or vaccination have been studied extensively, cellular immunity has received less attention. Data from the mouse NoV model suggest that T cells are critical for preventing persistence and achieving viral clearance, but little is known about NoV-specific T-cell immunity in humans, particularly at mucosal sites. METHODS We screened peripheral blood mononuclear cells from 3 volunteers with an overlapping NoV peptide library. We then used HLA-peptide tetramers to track virus-specific CD8+ T cells in peripheral, lymphoid, and intestinal tissues. Tetramer+ cells were further characterized using markers for cellular trafficking, exhaustion, cytotoxicity, and proliferation. RESULTS We defined 7 HLA-restricted immunodominant class I epitopes that were highly conserved across pandemic strains from genogroup II.4. NoV-specific CD8+ T cells with central, effector, or tissue-resident memory phenotypes were present at all sites and were especially abundant in the intestinal lamina propria. The properties and differentiation states of tetramer+ cells varied across donors and epitopes. CONCLUSIONS Our findings are an important step toward defining the breadth, distribution, and properties of human NoV T-cell immunity. Moreover, the molecular tools we have developed can be used to evaluate future vaccines and engineer novel cellular therapeutics.
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Affiliation(s)
- Ajinkya Pattekar
- Department of Medicine, Division of Gastroenterology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania
| | - Lena S. Mayer
- Department of Medicine, Division of Gastroenterology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania,Department of Medicine II: Gastroenterology, Hepatology, Endocrinology, and Infectious Disease, University Medical Center Freiburg, Freiburg, Germany
| | - Chi Wai Lau
- Department of Medicine, Division of Gastroenterology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania
| | - Chengyang Liu
- Department of Surgery, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania
| | - Olesya Palko
- Department of Medicine, Division of Gastroenterology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania,Department of Orthopedic Surgery, Montefiore Medical Center, Bronx, New York
| | - Meenakshi Bewtra
- Department of Medicine, Division of Gastroenterology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania,Center for Clinical Epidemiology and Biostatistics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania
| | | | - Lisa C. Lindesmith
- Department of Epidemiology, University of North Carolina, Chapel Hill, North Carolina
| | - Paul D. Brewer-Jensen
- Department of Epidemiology, University of North Carolina, Chapel Hill, North Carolina
| | - Ralph S. Baric
- Department of Epidemiology, University of North Carolina, Chapel Hill, North Carolina
| | - Michael R. Betts
- Department of Microbiology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania
| | - Ali Naji
- Department of Surgery, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania
| | - E. John Wherry
- Department of Systems Pharmacology and Translational Therapeutics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania,Institute for Immunology, University of Pennsylvania Perelman School of Medicine, Philadelphia, Pennsylvania,Parker Institute for Cancer Immunotherapy, University of Pennsylvania Perelman School of Medicine, Philadelphia, Pennsylvania
| | - Vesselin T. Tomov
- Department of Medicine, Division of Gastroenterology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania,Institute for Immunology, University of Pennsylvania Perelman School of Medicine, Philadelphia, Pennsylvania,Correspondence Address correspondence to: Vesselin Tomov, MD, PhD, Department of Medicine, Division of Gastroenterology, University of Pennsylvania, Perelman School of Medicine, 421 Curie Boulevard, BRB 313, Philadelphia, Pennsylvania 19103. fax: (215) 349-5915.
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10
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Xu M, Lu F, Lyu C, Wu Q, Zhang J, Tian P, Xue L, Xu T, Wang D. Broad-range and effective detection of human noroviruses by colloidal gold immunochromatographic assay based on the shell domain of the major capsid protein. BMC Microbiol 2021; 21:22. [PMID: 33430771 PMCID: PMC7798207 DOI: 10.1186/s12866-020-02084-z] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2020] [Accepted: 12/29/2020] [Indexed: 12/16/2022] Open
Abstract
BACKGROUND Human noroviruses (HuNoVs) are a major cause of nonbacterial gastroenteritis in all age groups worldwide. HuNoVs can be detected in vitro using molecular assays such as RT-PCR and RT-qPCR. However, these molecular-based techniques require special equipment, unique reagents, experienced personnel, and extended time to obtain results. Besides, the diversity of viral genotypes is high. Therefore, methods that are rapid, broad-range and effective in the detection of HuNoVs are desiderated for screening the feces or vomit of infected people during outbreaks. RESULTS In this study, a colloidal-gold-based immunochromatographic assay (ICA) was developed for effective detection of HuNoVs in clinical samples. Monoclonal antibodies (MAbs) against the shell (S) domain in the major capsid protein of HuNoVs were used in the ICA. The limitations of detection for HuNoVs in clinical samples were 1.2 × 106 genomic copies per gram of stool sample (gc/g) and 4.4 × 105 gc/g for genogroup I and II (GI and GII) HuNoVs, respectively. A total of 122 clinical samples were tested for HuNoVs by ICA and compared against RT-qPCR. The relative sensitivity, specificity and agreement of ICA was 84.2% (95% CI: 83.6-84.8%), 100.0% (95% CI: 98.5-100.0%) and 87.7% (95% CI: 85.6-89.8%), respectively. No cross-reaction with other common enteric viruses or bacteria was observed. The ICA detected a broad range of genotypes, including GI.1, GI.3, GI.4, GI.6, GI.14, GII.2, GII.3, GII.4, GII.6, GII.13, and GII.17 HuNoVs. CONCLUSIONS This study demonstrates that ICA targeting the S domain of VP1 is a promising candidate for effectively identifying the different genotypes of HuNoVs in clinical samples with high sensitivity and specificity.
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Affiliation(s)
- Meng Xu
- Department of Food Science and Technology, School of Agriculture and Biology, Shanghai Jiao Tong University, Shanghai, 200240, China
| | - Feifeng Lu
- Department of Food Science and Technology, School of Agriculture and Biology, Shanghai Jiao Tong University, Shanghai, 200240, China
| | - Chenang Lyu
- Department of Food Science and Technology, School of Agriculture and Biology, Shanghai Jiao Tong University, Shanghai, 200240, China
| | - Qingping Wu
- State Key Laboratory of Applied Microbiology Southern China, Guangdong Provincial Key Laboratory of Microbial Culture Collection and Application, Guangdong Open Laboratory of Applied Microbiology, Guangdong Institute of Microbiology, Guangzhou, 510070, China
| | - Jumei Zhang
- State Key Laboratory of Applied Microbiology Southern China, Guangdong Provincial Key Laboratory of Microbial Culture Collection and Application, Guangdong Open Laboratory of Applied Microbiology, Guangdong Institute of Microbiology, Guangzhou, 510070, China
| | - Peng Tian
- Western Regional Research Center, Agricultural Research Service-United States Department of Agriculture, Produce Safety and Microbiology Research Unit, Albany, CA, 94706, USA.
| | - Liang Xue
- State Key Laboratory of Applied Microbiology Southern China, Guangdong Provincial Key Laboratory of Microbial Culture Collection and Application, Guangdong Open Laboratory of Applied Microbiology, Guangdong Institute of Microbiology, Guangzhou, 510070, China
| | - Ting Xu
- Department of Food Science and Technology, School of Agriculture and Biology, Shanghai Jiao Tong University, Shanghai, 200240, China
| | - Dapeng Wang
- Department of Food Science and Technology, School of Agriculture and Biology, Shanghai Jiao Tong University, Shanghai, 200240, China.
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Verardi R, Lindesmith LC, Tsybovsky Y, Gorman J, Chuang GY, Edwards CE, Brewer-Jensen PD, Mallory ML, Ou L, Schön A, Shi W, Tully ES, Georgiou G, Baric RS, Kwong PD. Disulfide stabilization of human norovirus GI.1 virus-like particles focuses immune response toward blockade epitopes. NPJ Vaccines 2020; 5:110. [PMID: 33318483 PMCID: PMC7736355 DOI: 10.1038/s41541-020-00260-w] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2020] [Accepted: 11/04/2020] [Indexed: 01/21/2023] Open
Abstract
Human noroviruses are non-enveloped, single-strand RNA viruses that cause pandemic outbreaks of acute gastroenteritis. A bivalent vaccine containing GI.1 and GII.4 virus-like particles (VLPs) has been shown to be safe and highly immunogenic, but its efficacy and durability have been limited. Here, we show that norovirus GI.1 VLPs are unstable and contain a substantial fraction of dissociated VLP components. Broadly reactive, non-neutralizing antibodies isolated from vaccinated donors bound to the dissociated components, but not to the intact VLPs. Engineering of interprotomer disulfide bonds within the shell domain prevented disassembly of the VLPs, while preserving antibody accessibility to blockade epitopes. Without adjuvant, mice immunized with stabilized GI.1 VLPs developed faster blockade antibody titers compared to immunization with wild-type GI.1 VLPs. In addition, immunization with stabilized particles focused immune responses toward surface-exposed epitopes and away from occluded epitopes. Overall, disulfide-stabilized norovirus GI.1 VLPs elicited improved responses over the non-disulfide-stabilized version, suggesting their promise as candidate vaccines.
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Affiliation(s)
- Raffaello Verardi
- Vaccine Research Center, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, 20892, MD, USA
| | - Lisa C Lindesmith
- Department of Epidemiology, University of North Carolina, Chapel Hill, 27599, NC, USA
| | - Yaroslav Tsybovsky
- Electron Microscopy Laboratory, Cancer Research Technology Program, Leidos Biomedical Research, Inc., Frederick National Laboratory for Cancer Research, Frederick, 21702, MD, USA
| | - Jason Gorman
- Vaccine Research Center, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, 20892, MD, USA
| | - Gwo-Yu Chuang
- Vaccine Research Center, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, 20892, MD, USA
| | - Caitlin E Edwards
- Department of Epidemiology, University of North Carolina, Chapel Hill, 27599, NC, USA
| | - Paul D Brewer-Jensen
- Department of Epidemiology, University of North Carolina, Chapel Hill, 27599, NC, USA
| | - Michael L Mallory
- Department of Epidemiology, University of North Carolina, Chapel Hill, 27599, NC, USA
| | - Li Ou
- Vaccine Research Center, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, 20892, MD, USA
| | - Arne Schön
- Department of Biology, Johns Hopkins University, Baltimore, 21218, MD, USA
| | - Wei Shi
- Vaccine Research Center, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, 20892, MD, USA
| | - Ena S Tully
- Vaccine Research Center, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, 20892, MD, USA
| | - George Georgiou
- Department of Chemical Engineering, University of Texas at Austin, Austin, 78712, TX, USA
| | - Ralph S Baric
- Department of Epidemiology, University of North Carolina, Chapel Hill, 27599, NC, USA.
| | - Peter D Kwong
- Vaccine Research Center, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, 20892, MD, USA.
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12
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High-Resolution Mapping of Human Norovirus Antigens via Genomic Phage Display Library Selections and Deep Sequencing. J Virol 2020; 95:JVI.01495-20. [PMID: 33055250 DOI: 10.1128/jvi.01495-20] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2020] [Accepted: 10/06/2020] [Indexed: 12/16/2022] Open
Abstract
Norovirus (NoV) infections are a leading cause of gastroenteritis. The humoral immune response plays an important role in the control of NoV, and recent studies have identified neutralizing antibodies that bind the capsid protein VP1 to block viral infection. Here, we utilize a NoV GI.1 Jun-Fos-assisted phage display library constructed from randomly fragmented genomic DNA coupled with affinity selection for antibody binding and subsequent deep sequencing to map epitopes. The epitopes were identified by quantitating the phage clones before and after affinity selection and aligning the sequences of the most enriched peptides. The HJT-R3-A9 single-chain variable fragment (scFv) antibody epitope was mapped to a 12-amino-acid region of VP1 that is also the binding site for several previously identified monoclonal antibodies. We synthesized the 12-mer peptide and found that it binds the scFv antibody with a KD (equilibrium dissociation constant) of 46 nM. Further, alignment of enriched peptides after affinity selection on rabbit anti-NoV polyclonal antisera revealed five families of overlapping sequences that define distinct epitopes in VP1. One of these is identical to the HJT-R3-A9 scFv epitope, further suggesting that it is immunodominant. Similarly, other epitopes identified using the polyclonal antisera overlap binding sites for previously reported monoclonal antibodies, suggesting that they are also dominant epitopes. The results demonstrate that affinity selection and deep sequencing of the phage library provide sufficient resolution to map multiple epitopes simultaneously from complex samples such as polyclonal antisera. This approach can be extended to examine the antigenic landscape in patient sera to facilitate investigation of the immune response to NoV.IMPORTANCE NoV infections are a leading cause of gastroenteritis in the United States. Human NoVs exhibit extensive genetic and antigenic diversity, which makes it challenging to design a vaccine that provides broad protection against infection. Antibodies developed during the immune response play an important role in the control of NoV infections. Neutralizing antibodies that act by sterically blocking the site on the virus used to bind human cells have been identified. Identification of other antibody binding sites associated with virus neutralization is therefore of interest. Here, we use a high-resolution method to map multiple antibody binding sites simultaneously from complex serum samples. The results show that a relatively small number of sites on the virus bind a large number of independently generated antibodies, suggesting that immunodominance plays a role in the humoral immune response to NoV infections.
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Chowdhury AD, Sharmin S, Nasrin F, Yamazaki M, Abe F, Suzuki T, Park EY. Use of Target-Specific Liposome and Magnetic Nanoparticle Conjugation for the Amplified Detection of Norovirus. ACS APPLIED BIO MATERIALS 2020; 3:3560-3568. [PMID: 35025226 DOI: 10.1021/acsabm.0c00213] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Viral diseases are one of the most life-threatening diseases as they can erupt unpredictably and spread rapidly in any medium with a very small number of particles. Therefore, the key for lethal virus detection should be highly sensitive in the early-stage detection, which can help increase the chance of survival. Amplification of the detecting signal is one of the most promising mechanisms for the detection of low-concentration analytes. A proper amplification can develop such a kind of system where a small number of particles can produce intense signals for a prominent detection. Keeping this in mind, in this report, we have presented a fluorometric method to detect norovirus (NoV) by a newly developed fluorophore-labeled liposome and a magnetically modified Fe3O4 combined system. Homogeneously distributed amine-functionalized liposomes have been constructed filled with a strong fluorophore of calcein. Simultaneously, (3-aminopropyl)-triethoxysilane (APTES)-functionalized Fe3O4 nanoparticles are also synthesized by the standard silanization process, and these two separately synthesized nanoparticles were functionalized with an antibody to achieve specificity. The Fe3O4 and calcein-liposome system has been applied for NoV detection, which was magnetically separated from the analyte medium and then externally burst to release the fluorophores from the core of the liposome. The easiness, rapidity, and sensitivity in a wide linear range can offer a huge potential of this method in point-of-care diagnostics.
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Affiliation(s)
- Ankan Dutta Chowdhury
- Laboratory of Biotechnology, Research Institute of Green Science and Technology, Shizuoka University, 836 Ohya, Suruga-ku, Shizuoka 422-8529, Japan
| | - Sabrina Sharmin
- Laboratory of Biotechnology, Research Institute of Green Science and Technology, Shizuoka University, 836 Ohya, Suruga-ku, Shizuoka 422-8529, Japan
| | - Fahmida Nasrin
- Laboratory of Biotechnology, Graduate School of Science and Technology, Shizuoka University, 836 Ohya, Suruga-ku, Shizuoka 422-8529, Japan
| | - Masahito Yamazaki
- Research Institute of Electronics, Shizuoka University, 836 Ohya, Suruga-ku, Shizuoka 422-8529, Japan
| | - Fuyuki Abe
- Department of Microbiology, Shizuoka Institute of Environment and Hygiene, 4-27-2, Kita-ando, Aoi-ku, Shizuoka 420-8637, Japan
| | - Tetsuro Suzuki
- Department of Infectious Diseases, Hamamatsu University School of Medicine, 1-20-Higashi-ku, Handa-yama, Hamamatsu 431-3192, Japan
| | - Enoch Y Park
- Laboratory of Biotechnology, Research Institute of Green Science and Technology, Shizuoka University, 836 Ohya, Suruga-ku, Shizuoka 422-8529, Japan.,Laboratory of Biotechnology, Graduate School of Science and Technology, Shizuoka University, 836 Ohya, Suruga-ku, Shizuoka 422-8529, Japan
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14
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15
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The Antigenic Topology of Norovirus as Defined by B and T Cell Epitope Mapping: Implications for Universal Vaccines and Therapeutics. Viruses 2019; 11:v11050432. [PMID: 31083353 PMCID: PMC6563215 DOI: 10.3390/v11050432] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2019] [Revised: 05/07/2019] [Accepted: 05/08/2019] [Indexed: 12/11/2022] Open
Abstract
Human norovirus (HuNoV) is the leading cause of acute nonbacterial gastroenteritis. Vaccine design has been confounded by the antigenic diversity of these viruses and a limited understanding of protective immunity. We reviewed 77 articles published since 1988 describing the isolation, function, and mapping of 307 unique monoclonal antibodies directed against B cell epitopes of human and murine noroviruses representing diverse Genogroups (G). Of these antibodies, 91, 153, 21, and 42 were reported as GI-specific, GII-specific, MNV GV-specific, and G cross-reactive, respectively. Our goal was to reconstruct the antigenic topology of noroviruses in relationship to mapped epitopes with potential for therapeutic use or inclusion in universal vaccines. Furthermore, we reviewed seven published studies of norovirus T cell epitopes that identified 18 unique peptide sequences with CD4- or CD8-stimulating activity. Both the protruding (P) and shell (S) domains of the major capsid protein VP1 contained B and T cell epitopes, with the majority of neutralizing and HBGA-blocking B cell epitopes mapping in or proximal to the surface-exposed P2 region of the P domain. The majority of broadly reactive B and T cell epitopes mapped to the S and P1 arm of the P domain. Taken together, this atlas of mapped B and T cell epitopes offers insight into the promises and challenges of designing universal vaccines and immunotherapy for the noroviruses.
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Di Profio F, Sarchese V, Melegari I, Palombieri A, Massirio I, Bermudez Sanchez S, Friedrich KG, Coccia F, Marsilio F, Martella V, Di Martino B. Seroprevalence for norovirus genogroups GII and GIV in captive non-human primates. Zoonoses Public Health 2019; 66:310-315. [PMID: 30737897 DOI: 10.1111/zph.12566] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2018] [Revised: 01/08/2019] [Accepted: 01/10/2019] [Indexed: 01/22/2023]
Abstract
Noroviruses (NoVs) are a major cause of epidemic gastroenteritis in children and adults. Several pieces of evidence suggest that viruses genetically and antigenically closely related to human NoVs might infect animals, raising public health concerns about potential cross-species transmission. The natural susceptibility of non-human primates (NPHs) to human NoV infections has already been reported, but a limited amount of data is currently available. In order to start filling this gap, we screened a total of 86 serum samples of seven different species of NPHs housed at the Zoological Garden (Bioparco) of Rome (Italy), collected between 2001 and 2017, using an enzyme-linked immunosorbent assay (ELISA) based on virus-like particles (VLPs) of human GII.4 and GIV.1 NoVs. Antibodies specific for both genotypes were detected with an overall prevalence of 32.6%. In detail, IgG antibodies against GII.4 NoVs were found in 18 Japanese macaques (29.0%, 18/62), a mandrill (10.0%, 1/10), a white-crowned mangabey (16.6%, 1/6) and in an orangutan (33.3%, 1/3). Twelve macaques (19.3%, 12/62), five mandrills (50.0%, 5/10), two chimpanzees (100%, 2/2) and a white-crowned mangabey (16.6%, 1/6) showed antibodies for GIV.1 NoVs. The findings of this study confirm the natural susceptibility of captive NHPs to GII NoV infections. In addition, IgG antibodies against GIV.1 were detected, suggesting that NHPs are exposed to GIV NoVs or to antigenically related NoV strains.
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Affiliation(s)
- Federica Di Profio
- Faculty of Veterinary Medicine, Università degli Studi di Teramo, Teramo, Italy
| | - Vittorio Sarchese
- Faculty of Veterinary Medicine, Università degli Studi di Teramo, Teramo, Italy
| | - Irene Melegari
- Faculty of Veterinary Medicine, Università degli Studi di Teramo, Teramo, Italy
| | - Andrea Palombieri
- Faculty of Veterinary Medicine, Università degli Studi di Teramo, Teramo, Italy
| | | | | | | | | | - Fulvio Marsilio
- Faculty of Veterinary Medicine, Università degli Studi di Teramo, Teramo, Italy
| | - Vito Martella
- Faculty of Veterinary Medicine, Università Aldo Moro di Bari, Valenzano, Italy
| | - Barbara Di Martino
- Faculty of Veterinary Medicine, Università degli Studi di Teramo, Teramo, Italy
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Manuel CS, Moore MD, Jaykus LA. Predicting human norovirus infectivity - Recent advances and continued challenges. Food Microbiol 2018; 76:337-345. [DOI: 10.1016/j.fm.2018.06.015] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2018] [Revised: 05/17/2018] [Accepted: 06/24/2018] [Indexed: 01/06/2023]
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18
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Zheng L, Wang W, Liu J, Chen X, Li S, Wang Q, Huo Y, Qin C, Shen S, Wang M. Characterization of a Norovirus-specific monoclonal antibody that exhibits wide spectrum binding activities. J Med Virol 2018; 90:671-676. [PMID: 29236287 DOI: 10.1002/jmv.25001] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2017] [Accepted: 11/29/2017] [Indexed: 12/27/2022]
Abstract
Noroviruses (NoVs) are increasingly recognized as the leading cause of acute non-bacterial gastroenteritis worldwide. To screen for NoV-specific monoclonal antibodies (mAbs) with wide spectrum binding activities that could be used for the development of NoV-related detection reagents, we immunized mice with a combination of virus like particles (VLPs) derived from eight different genotypes (two from genogroup I and six from genogroup II), of which two (GI.7 and GII.2) were newly produced VLPs. Indirect enzyme-linked immunosorbent assay (ELISA) confirmed that two mAbs (8D8 and 10B11) bound to all eight major capsid proteins (VP1) with varied binding abilities. Epitope mapping using short peptides covering the N-terminal half of GII.3 VP1 indicated that the binding site of mAb 8D8 was located between amino acid 31 and 60. Multiple amino acid sequence alignment of VP1 suggested that this site harbors conservative sequences across all genogroups. Indirect and sandwich ELISA indicated that mAb 8D8 was unable bind intact VLPs. In summary, we successfully produced GI.7 and GII.2 VLPs using recombinant baculovirus expression system and a cross-reactive mAb by immunizing mice with eight different VLPs that might be useful in the studying and detecting NoVs.
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Affiliation(s)
- Lijun Zheng
- The Sixth People's Hospital of Zhengzhou, Zhengzhou, P. R. China
| | - Wenhui Wang
- Wuhan Institute of Biological Products, Wuhan, P. R. China
| | - Jinjin Liu
- The Sixth People's Hospital of Zhengzhou, Zhengzhou, P. R. China
| | - Xuhui Chen
- The Sixth People's Hospital of Zhengzhou, Zhengzhou, P. R. China
| | - Sanjing Li
- The Sixth People's Hospital of Zhengzhou, Zhengzhou, P. R. China
| | - Qiaoli Wang
- The Sixth People's Hospital of Zhengzhou, Zhengzhou, P. R. China
| | - Yuqi Huo
- The Sixth People's Hospital of Zhengzhou, Zhengzhou, P. R. China
| | - Chuan Qin
- The Sixth People's Hospital of Zhengzhou, Zhengzhou, P. R. China
| | - Shuo Shen
- Wuhan Institute of Biological Products, Wuhan, P. R. China
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19
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Dietrich MH, Harprecht C, Stehle T. The bulky and the sweet: How neutralizing antibodies and glycan receptors compete for virus binding. Protein Sci 2017; 26:2342-2354. [PMID: 28986957 PMCID: PMC5699497 DOI: 10.1002/pro.3319] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2017] [Revised: 10/04/2017] [Accepted: 10/04/2017] [Indexed: 12/23/2022]
Abstract
Numerous viruses rely on glycan receptor binding as the initial step in host cell infection. Engagement of specific glycan receptors such as sialylated carbohydrates, glycosaminoglycans, or histo-blood group antigens can determine host range, tissue tropism, and pathogenicity. Glycan receptor-binding sites are typically located in exposed regions on viral surfaces-sites that are also generally prone to binding of neutralizing antibodies that directly interfere with virus-glycan receptor interactions. In this review, we examine the locations and architecture of the glycan- and antibody-binding sites in four different viruses with stalk-like attachment proteins (reovirus, influenza virus, norovirus, and coronavirus) and investigate the mechanisms by which antibodies block glycan recognition. Those viruses exemplify that direct molecular mimicking of glycan receptors by antibodies is rare and further demonstrate that antibodies often partly overlap or bind sufficiently close to the receptor-binding region to hinder access to this site, achieving neutralization partially because of the epitope location and partly due to their sheer size.
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Affiliation(s)
- Melanie H. Dietrich
- Interfaculty Institute of BiochemistryUniversity of TuebingenTuebingenGermany
| | - Christina Harprecht
- Interfaculty Institute of BiochemistryUniversity of TuebingenTuebingenGermany
| | - Thilo Stehle
- Interfaculty Institute of BiochemistryUniversity of TuebingenTuebingenGermany
- Department of PediatricsVanderbilt University School of MedicineNashvilleTennesseeUSA
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20
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Norovirus Escape from Broadly Neutralizing Antibodies Is Limited to Allostery-Like Mechanisms. mSphere 2017; 2:mSphere00334-17. [PMID: 29062895 PMCID: PMC5646240 DOI: 10.1128/msphere.00334-17] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2017] [Accepted: 09/27/2017] [Indexed: 01/03/2023] Open
Abstract
The simplest and most common way for viruses to escape antibody neutralization is by mutating residues that are essential for antibody binding. Escape mutations are strongly selected for by their effect on viral fitness, which is most often related to issues of protein folding, particle assembly, and capsid function. The studies presented here demonstrated that a broadly neutralizing antibody to mouse norovirus binds to an exposed surface but that the only escape mutants that arose were distal to the antibody binding surface. To understand this finding, we performed an in silico analysis that suggested that those escape mutations blocked antibody binding by affecting structural plasticity. This kind of antigenic region—one that gives rise to broadly neutralizing antibodies but that the virus finds difficult to escape from—is therefore ideal for vaccine development. Ideal antiviral vaccines elicit antibodies (Abs) with broad strain recognition that bind to regions that are difficult to mutate for escape. Using 10 murine norovirus (MNV) strains and 5 human norovirus (HuNoV) virus-like particles (VLPs), we identified monoclonal antibody (MAb) 2D3, which broadly neutralized all MNV strains tested. Importantly, escape mutants corresponding to this antibody were very slow to develop and were distal to those raised against our previously studied antibody, A6.2. To understand the atomic details of 2D3 neutralization, we determined the cryo-electron microscopy (cryo-EM) structure of the 2D3/MNV1 complex. Interestingly, 2D3 binds to the top of the P domain, very close to where A6.2 binds, but the only escape mutations identified to date fall well outside the contact regions of both 2D3 and A6.2. To determine how mutations in distal residues could block antibody binding, we used molecular dynamics flexible fitting simulations of the atomic structures placed into the density map to examine the 2D3/MNV1 complex and these mutations. Our findings suggest that the escape mutant, V339I, may stabilize a salt bridge network at the P-domain dimer interface that, in an allostery-like manner, affects the conformational relaxation of the P domain and the efficiency of binding. They further highlight the unusual antigenic surface bound by MAb 2D3, one which elicits cross-reactive antibodies but which the virus is unable to alter to escape neutralization. These results may be leveraged to generate norovirus (NoV) vaccines containing broadly neutralizing antibodies. IMPORTANCE The simplest and most common way for viruses to escape antibody neutralization is by mutating residues that are essential for antibody binding. Escape mutations are strongly selected for by their effect on viral fitness, which is most often related to issues of protein folding, particle assembly, and capsid function. The studies presented here demonstrated that a broadly neutralizing antibody to mouse norovirus binds to an exposed surface but that the only escape mutants that arose were distal to the antibody binding surface. To understand this finding, we performed an in silico analysis that suggested that those escape mutations blocked antibody binding by affecting structural plasticity. This kind of antigenic region—one that gives rise to broadly neutralizing antibodies but that the virus finds difficult to escape from—is therefore ideal for vaccine development.
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21
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Ball JP, Springer MJ, Ni Y, Finger-Baker I, Martinez J, Hahn J, Suber JF, DiMarco AV, Talton JD, Cobb RR. Intranasal delivery of a bivalent norovirus vaccine formulated in an in situ gelling dry powder. PLoS One 2017; 12:e0177310. [PMID: 28545100 PMCID: PMC5436670 DOI: 10.1371/journal.pone.0177310] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2016] [Accepted: 04/25/2017] [Indexed: 11/19/2022] Open
Abstract
The global health community is beginning to understand the burden of norovirus-associated disease, which has a significant impact in both developed and developing countries. Norovirus virus like particle (VLP)-based vaccines are currently under development and have been shown to elicit systemic and mucosal immune responses when delivered intranasally. In the present study, we describe the use of a dry powder formulation (GelVac™) with an in situ gelling polysaccharide (GelSite™) extracted from Aloe vera for nasal delivery of a bivalent vaccine formulation containing both GI and GII.4 norovirus VLPs. Dose-ranging studies were performed to identify the optimal antigen dosages based on systemic and mucosal immune responses in guinea pigs and determine any antigenic interference. A dose-dependent increase in systemic and mucosal immunogenicity against each of the VLPs were observed as well as a boosting effect for each VLP after the second dosing. A total antigen dose of ≥50 μg of each GI and GII.4 VLPs was determined to be the maximally immunogenic dose in guinea pigs. The immunogenicity results of this bivalent formulation, taken together with previous work on monovalent GelVac™ norovirus vaccine formulation, provides a basis for future development of this norovirus VLP vaccine.
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Affiliation(s)
- Jordan P. Ball
- Research and Development Department, Nanotherapeutics, Inc., Alachua, Florida, United States of America
| | - Michael J. Springer
- Research and Development Department, Nanotherapeutics, Inc., Alachua, Florida, United States of America
| | - Yawei Ni
- Research and Development Department, Nanotherapeutics, Inc., Alachua, Florida, United States of America
| | - Isaac Finger-Baker
- Research and Development Department, Nanotherapeutics, Inc., Alachua, Florida, United States of America
| | - Juan Martinez
- Research and Development Department, Nanotherapeutics, Inc., Alachua, Florida, United States of America
| | - Jessica Hahn
- Research and Development Department, Nanotherapeutics, Inc., Alachua, Florida, United States of America
| | - John F. Suber
- Research and Development Department, Nanotherapeutics, Inc., Alachua, Florida, United States of America
| | - Ashley V. DiMarco
- Research and Development Department, Nanotherapeutics, Inc., Alachua, Florida, United States of America
| | - James D. Talton
- Research and Development Department, Nanotherapeutics, Inc., Alachua, Florida, United States of America
| | - Ronald R. Cobb
- Research and Development Department, Nanotherapeutics, Inc., Alachua, Florida, United States of America
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22
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Koromyslova A, Tripathi S, Morozov V, Schroten H, Hansman GS. Human norovirus inhibition by a human milk oligosaccharide. Virology 2017; 508:81-89. [PMID: 28505592 DOI: 10.1016/j.virol.2017.04.032] [Citation(s) in RCA: 87] [Impact Index Per Article: 12.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2017] [Revised: 04/24/2017] [Accepted: 04/28/2017] [Indexed: 01/30/2023]
Abstract
Human noroviruses are the leading cause of outbreaks of acute gastroenteritis. Norovirus interactions with histo-blood group antigens (HBGAs) are known to be important for an infection. In this study, we identified the HBGA binding pocket for an emerging GII genotype 17 (GII.17) variant using X-ray crystallography. The GII.17 variant bound the HBGA with an equivalent set of residues as the leading pandemic GII.4 variants. These structural data highlights the conserved nature of HBGA binding site between prevalent GII noroviruses. Noroviruses also interact with human milk oligosaccharides (HMOs), which mimic HBGAs and may function as receptor decoys. We previously showed that HMOs inhibited the binding of rarely detected GII.10 norovirus to HBGAs. We now found that an HMO, 2'-fucosyllactose (2'FL), additionally blocked both the GI.1 and GII.17 noroviruses from binding to HBGAs. Together, these findings provide evidence that 2'FL might function as a broadly reactive antiviral against multiple norovirus genogroups.
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Affiliation(s)
- Anna Koromyslova
- Schaller Research Group at the University of Heidelberg and the DKFZ, Heidelberg, Germany; Department of Infectious Diseases, Virology, University of Heidelberg, Heidelberg, Germany
| | - Shailesh Tripathi
- Schaller Research Group at the University of Heidelberg and the DKFZ, Heidelberg, Germany; Department of Infectious Diseases, Virology, University of Heidelberg, Heidelberg, Germany
| | - Vasily Morozov
- Department of Infectious Diseases, Virology, University of Heidelberg, Heidelberg, Germany; Pediatric Infectious Diseases Unit, University Children's Hospital Mannheim, University of Heidelberg, Mannheim, Germany
| | - Horst Schroten
- Pediatric Infectious Diseases Unit, University Children's Hospital Mannheim, University of Heidelberg, Mannheim, Germany
| | - Grant S Hansman
- Schaller Research Group at the University of Heidelberg and the DKFZ, Heidelberg, Germany; Department of Infectious Diseases, Virology, University of Heidelberg, Heidelberg, Germany.
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Hurwitz AM, Huang W, Kou B, Estes MK, Atmar RL, Palzkill T. Identification and Characterization of Single-Chain Antibodies that Specifically Bind GI Noroviruses. PLoS One 2017; 12:e0170162. [PMID: 28095447 PMCID: PMC5240998 DOI: 10.1371/journal.pone.0170162] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2016] [Accepted: 12/30/2016] [Indexed: 02/02/2023] Open
Abstract
Norovirus infections commonly lead to outbreaks of acute gastroenteritis and spread quickly, resulting in many health and economic challenges prior to diagnosis. Rapid and reliable diagnostic tests are therefore essential to identify infections and to guide the appropriate clinical responses at the point-of-care. Existing tools, including RT-PCR and enzyme immunoassays, pose several limitations based on the significant time, equipment and expertise required to elicit results. Immunochromatographic assays available for use at the point-of-care have poor sensitivity and specificity, especially for genogroup I noroviruses, thus requiring confirmation of results with more sensitive testing methods. Therefore, there is a clear need for novel reagents to help achieve quick and reliable results. In this study, we have identified two novel single-chain antibodies (scFvs)—named NJT-R3-A2 and NJT-R3-A3—that effectively detect GI.1 and GI.7 virus-like particles (VLPs) through selection of a phage display library against the P-domain of the GI.1 major capsid protein. The limits of detection by each scFv for GI.1 and GI.7 are 0.1 and 0.2 ng, and 6.25 and 25 ng, respectively. They detect VLPs with strong specificity in multiple diagnostic formats, including ELISAs and membrane-based dot blots, and in the context of norovirus-negative stool suspensions. The scFvs also detect native virions effectively in norovirus-positive clinical stool samples. Purified scFvs bind to GI.1 and GI.7 VLPs with equilibrium constant (KD) values of 27 nM and 49 nM, respectively. Overall, the phage-based scFv reagents identified and characterized here show utility for detecting GI.1 and GI.7 noroviruses in multiple diagnostic assay formats with strong specificity and sensitivity, indicating promise for integration into existing point-of-care tests to improve future diagnostics.
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Affiliation(s)
- Amy M. Hurwitz
- Interdepartmental Program in Translational Biology & Molecular Medicine, Baylor College of Medicine, Houston, Texas, United States of America
- Department of Pharmacology, Baylor College of Medicine, Houston, Texas, United States of America
| | - Wanzhi Huang
- Department of Pharmacology, Baylor College of Medicine, Houston, Texas, United States of America
| | - Baijun Kou
- Department of Molecular Virology & Microbiology, Baylor College of Medicine, Houston, Texas, United States of America
| | - Mary K. Estes
- Department of Molecular Virology & Microbiology, Baylor College of Medicine, Houston, Texas, United States of America
- Department of Medicine, Baylor College of Medicine, Houston, Texas, United States of America
| | - Robert L. Atmar
- Department of Molecular Virology & Microbiology, Baylor College of Medicine, Houston, Texas, United States of America
- Department of Medicine, Baylor College of Medicine, Houston, Texas, United States of America
| | - Timothy Palzkill
- Department of Pharmacology, Baylor College of Medicine, Houston, Texas, United States of America
- Department of Molecular Virology & Microbiology, Baylor College of Medicine, Houston, Texas, United States of America
- * E-mail:
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Human Norovirus Aptamer Exhibits High Degree of Target Conformation-Dependent Binding Similar to That of Receptors and Discriminates Particle Functionality. mSphere 2016; 1:mSphere00298-16. [PMID: 27830193 PMCID: PMC5093151 DOI: 10.1128/msphere.00298-16] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2016] [Accepted: 10/07/2016] [Indexed: 12/19/2022] Open
Abstract
Human noroviruses impose a considerable health burden globally. However, study of their inactivation is still challenging with currently reported cell culture models, as discrimination of infectious viral particles is still difficult. Traditionally, the ability of particles to bind putative carbohydrate receptors is conducted as a proxy for infectivity, but these receptors are inconsistent, expensive, and hard to purify/modify. We report a hitherto unexplored property of a different type of ligand, a nucleic acid aptamer, to mimic receptor binding behavior and assess capsid functionality for a selected strain of norovirus. These emerging ligands are cheaper, more stable, and easily synthesized/modified. The previously unutilized characteristic reported here demonstrates the fundamental potential of aptamers to serve as valuable, accessible tools for any microorganism that is difficult to cultivate/study. Therefore, this novel concept suggests a new use for aptamers that is of great value to the microbiological community—specifically that involving fastidious microbes. Although two in vitro cultivation methods have been reported, discrimination of infectious human norovirus particles for study of viral inactivation is still a challenge, as both rely on reverse transcriptase quantitative PCR. Histo-blood group antigen (HBGA) binding assays serve as a proxy for estimation of infectious particles; however, they are costly and difficult to purify/modify. Some evidence suggests that certain nucleic acid aptamers only bind intact target proteins, thus displaying a high degree of conformation-dependent binding. The objective of this proof-of-concept study was to characterize the degree of conformation-dependent binding a human norovirus aptamer, M6-2, displayed with the capsid of the norovirus GII.4 Sydney (SYV) strain as a model. SYV capsids were exposed to heat, and aptamer, receptor (HBGA), and antibody binding was assessed. M6-2 and the receptor displayed similarly little target sequence-dependent binding (2.0% ± 1.3% and 0.5% ± 1.2% signal, respectively) compared to that of NS14 (26.4% ± 3.9%). The decay rates calculated with M6-2 and the receptor were also not statistically significantly different (P > 0.05), and dynamic light scattering and electron microscopy confirmed these observations. Ligand docking simulations revealed multiple distinct contacts of M6-2 in the N-terminal P1 and P2 domains of the viral capsid, with some residues close to receptor binding residues. These data suggest that single-stranded DNA aptamers like M6-2 display a high degree of target conformation-dependent binding. It is the first time nucleic acid aptamers have had this characteristic utilized and investigated to discern the infectivity status of viral particles, and the data suggest that other aptamers may show promise as valuable ligands in the study of other fastidious microorganisms. IMPORTANCE Human noroviruses impose a considerable health burden globally. However, study of their inactivation is still challenging with currently reported cell culture models, as discrimination of infectious viral particles is still difficult. Traditionally, the ability of particles to bind putative carbohydrate receptors is conducted as a proxy for infectivity, but these receptors are inconsistent, expensive, and hard to purify/modify. We report a hitherto unexplored property of a different type of ligand, a nucleic acid aptamer, to mimic receptor binding behavior and assess capsid functionality for a selected strain of norovirus. These emerging ligands are cheaper, more stable, and easily synthesized/modified. The previously unutilized characteristic reported here demonstrates the fundamental potential of aptamers to serve as valuable, accessible tools for any microorganism that is difficult to cultivate/study. Therefore, this novel concept suggests a new use for aptamers that is of great value to the microbiological community—specifically that involving fastidious microbes.
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Springer MJ, Ni Y, Finger-Baker I, Ball JP, Hahn J, DiMarco AV, Kobs D, Horne B, Talton JD, Cobb RR. Preclinical dose-ranging studies of a novel dry powder norovirus vaccine formulation. Vaccine 2016; 34:1452-8. [PMID: 26873053 PMCID: PMC4775331 DOI: 10.1016/j.vaccine.2016.01.064] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2015] [Revised: 01/25/2016] [Accepted: 01/31/2016] [Indexed: 10/22/2022]
Abstract
Norovirus is the primary cause of viral gastroenteritis in humans with multiple genotypes currently circulating worldwide. The development of a successful norovirus vaccine is contingent on its ability to induce both systemic and mucosal antibody responses against a wide range of norovirus genotypes. Norovirus virus-like particles (VLPs) are known to elicit systemic and mucosal immune responses when delivered intranasally. Incorporation of these VLPs into an intranasal powder vaccine offers the advantage of simplicity and induction of neutralizing systemic and mucosal antibodies. Nasal immunization, which provides the advantage of ease of administration and a mucosal delivery mechanism, faces the real issue of limited nasal residence time due to mucociliary clearance. Herein, we describe a novel dry powder (GelVac™) formulation of GI or GII.4 norovirus VLPs, two dominant circulating genotypes, to identify the optimal antigen dosages based on systemic and mucosal immune responses in guinea pigs. Systemic and mucosal immunogenicity of each of the VLPs was observed in a dose-dependent manner. In addition, a boosting effect was observed after the second dosing of each VLP antigen. With the GelVac™ formulation, a total antigen dose of ≥ 15 μg was determined to be the maximally immunogenic dose for both GI and GII.4 norovirus VLPs based on evaluation for 56 days. Taken together, these results indicate that norovirus VLPs could be used as potential vaccine candidates without using an immunostimulatory adjuvant and provide a basis for the development of a GelVac™ bivalent GI/GII.4 norovirus VLP vaccine.
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Affiliation(s)
- Michael J Springer
- Research and Development Department, Nanotherapeutics, Inc., Alachua, FL, United States
| | - Yawei Ni
- Research and Development Department, Nanotherapeutics, Inc., Alachua, FL, United States
| | - Isaac Finger-Baker
- Research and Development Department, Nanotherapeutics, Inc., Alachua, FL, United States
| | - Jordan P Ball
- Research and Development Department, Nanotherapeutics, Inc., Alachua, FL, United States
| | - Jessica Hahn
- Research and Development Department, Nanotherapeutics, Inc., Alachua, FL, United States
| | - Ashley V DiMarco
- Research and Development Department, Nanotherapeutics, Inc., Alachua, FL, United States
| | - Dean Kobs
- Toxicology Department, Battelle Memorial Institute, West Jefferson, OH, United States
| | - Bobbi Horne
- Battelle Eastern Science and Technology Center, Aberdeen, MD, United States
| | - James D Talton
- Research and Development Department, Nanotherapeutics, Inc., Alachua, FL, United States
| | - Ronald R Cobb
- Research and Development Department, Nanotherapeutics, Inc., Alachua, FL, United States.
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Antigenic and Cryo-Electron Microscopy Structure Analysis of a Chimeric Sapovirus Capsid. J Virol 2015; 90:2664-75. [PMID: 26699644 DOI: 10.1128/jvi.02916-15] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2015] [Accepted: 12/18/2015] [Indexed: 12/13/2022] Open
Abstract
UNLABELLED The capsid protein (VP1) of all caliciviruses forms an icosahedral particle with two principal domains, shell (S) and protruding (P) domains, which are connected via a flexible hinge region. The S domain forms a scaffold surrounding the nucleic acid, while the P domains form a homodimer that interacts with receptors. The P domain is further subdivided into two subdomains, termed P1 and P2. The P2 subdomain is likely an insertion in the P1 subdomain; consequently, the P domain is divided into the P1-1, P2, and P1-2 subdomains. In order to investigate capsid antigenicity, N-terminal (N-term)/S/P1-1 and P2/P1-2 were switched between two sapovirus genotypes GI.1 and GI.5. The chimeric VP1 constructs were expressed in insect cells and were shown to self-assemble into virus-like particles (VLPs) morphologically similar to the parental VLPs. Interestingly, the chimeric VLPs had higher levels of cross-reactivities to heterogeneous antisera than the parental VLPs. In order to better understand the antigenicity from a structural perspective, we determined an intermediate-resolution (8.5-Å) cryo-electron microscopy (cryo-EM) structure of a chimeric VLP and developed a VP1 homology model. The cryo-EM structure revealed that the P domain dimers were raised slightly (∼5 Å) above the S domain. The VP1 homology model allowed us predict the S domain (67-229) and P1-1 (229-280), P2 (281-447), and P1-2 (448-567) subdomains. Our results suggested that the raised P dimers might expose immunoreactive S/P1-1 subdomain epitopes. Consequently, the higher levels of cross-reactivities with the chimeric VLPs resulted from a combination of GI.1 and GI.5 epitopes. IMPORTANCE We developed sapovirus chimeric VP1 constructs and produced the chimeric VLPs in insect cells. We found that both chimeric VLPs had a higher level of cross-reactivity against heterogeneous VLP antisera than the parental VLPs. The cryo-EM structure of one chimeric VLP (Yokote/Mc114) was solved to 8.5-Å resolution. A homology model of the VP1 indicated for the first time the putative S and P (P1-1, P2, and P1-2) domains. The overall structure of Yokote/Mc114 contained features common among other caliciviruses. We showed that the P2 subdomain was mainly involved in the homodimeric interface, whereas a large gap between the P1 subdomains had fewer interactions.
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Singh BK, Koromyslova A, Hansman GS. Structural analysis of bovine norovirus protruding domain. Virology 2015; 487:296-301. [PMID: 26599362 DOI: 10.1016/j.virol.2015.10.022] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2015] [Revised: 09/01/2015] [Accepted: 10/21/2015] [Indexed: 11/27/2022]
Abstract
We determined a structure of a bovine (genogroup III, GIII) norovirus capsid protruding (P) domain using X-ray crystallography. The bovine P domain was reminiscent of other norovirus genogroups (GI, GII, GIV, and GV), but closely matched the human GI P domain. We also identified a monoclonal antibody that was capable of binding the five different (GI-GV) P domains. Our data suggests that genetically diverse noroviruses still contain common epitopes.
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Affiliation(s)
- Bishal Kumar Singh
- Schaller Research Group at the University of Heidelberg and the DKFZ, Heidelberg 69120, Germany; Department of Infectious Diseases, Virology, University of Heidelberg, Heidelberg 69120, Germany
| | - Anna Koromyslova
- Schaller Research Group at the University of Heidelberg and the DKFZ, Heidelberg 69120, Germany; Department of Infectious Diseases, Virology, University of Heidelberg, Heidelberg 69120, Germany
| | - Grant S Hansman
- Schaller Research Group at the University of Heidelberg and the DKFZ, Heidelberg 69120, Germany; Department of Infectious Diseases, Virology, University of Heidelberg, Heidelberg 69120, Germany.
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28
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Garaicoechea L, Aguilar A, Parra GI, Bok M, Sosnovtsev SV, Canziani G, Green KY, Bok K, Parreño V. Llama nanoantibodies with therapeutic potential against human norovirus diarrhea. PLoS One 2015; 10:e0133665. [PMID: 26267898 PMCID: PMC4534396 DOI: 10.1371/journal.pone.0133665] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2015] [Accepted: 06/30/2015] [Indexed: 11/24/2022] Open
Abstract
Noroviruses are a major cause of acute gastroenteritis, but no vaccines or therapeutic drugs are available. Llama-derived single chain antibody fragments (also called VHH) are small, recombinant monoclonal antibodies of 15 kDa with several advantages over conventional antibodies. The aim of this study was to generate recombinant monoclonal VHH specific for the two major norovirus (NoV) genogroups (GI and GII) in order to investigate their potential as immunotherapy for the treatment of NoV diarrhea. To accomplish this objective, two llamas were immunized with either GI.1 (Norwalk-1968) or GII.4 (MD2004) VLPs. After immunization, peripheral blood lymphocytes were collected and used to generate two VHH libraries. Using phage display technology, 10 VHH clones specific for GI.1, and 8 specific for GII.4 were selected for further characterization. All VHH recognized conformational epitopes in the P domain of the immunizing VP1 capsid protein, with the exception of one GII.4 VHH that recognized a linear P domain epitope. The GI.1 VHHs were highly specific for the immunizing GI.1 genotype, with only one VHH cross-reacting with GI.3 genotype. The GII.4 VHHs reacted with the immunizing GII.4 strain and showed a varying reactivity profile among different GII genotypes. One VHH specific for GI.1 and three specific for GII.4 could block the binding of homologous VLPs to synthetic HBGA carbohydrates, saliva, and pig gastric mucin, and in addition, could inhibit the hemagglutination of red blood cells by homologous VLPs. The ability of Nov-specific VHHs to perform well in these surrogate neutralization assays supports their further development as immunotherapy for NoV treatment and immunoprophylaxis.
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Affiliation(s)
| | - Andrea Aguilar
- Instituto de Virología, INTA, Castelar, Buenos Aires, Argentina
| | - Gabriel I. Parra
- Laboratory of Infectious Diseases, NIAID, National Institutes of Health, Bethesda, Maryland, United States of America
| | - Marina Bok
- Instituto de Virología, INTA, Castelar, Buenos Aires, Argentina
| | - Stanislav V. Sosnovtsev
- Laboratory of Infectious Diseases, NIAID, National Institutes of Health, Bethesda, Maryland, United States of America
| | | | - Kim Y. Green
- Laboratory of Infectious Diseases, NIAID, National Institutes of Health, Bethesda, Maryland, United States of America
| | - Karin Bok
- Laboratory of Infectious Diseases, NIAID, National Institutes of Health, Bethesda, Maryland, United States of America
| | - Viviana Parreño
- Instituto de Virología, INTA, Castelar, Buenos Aires, Argentina
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29
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Moore MD, Escudero-Abarca BI, Suh SH, Jaykus LA. Generation and characterization of nucleic acid aptamers targeting the capsid P domain of a human norovirus GII.4 strain. J Biotechnol 2015; 209:41-9. [PMID: 26080079 DOI: 10.1016/j.jbiotec.2015.06.389] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2015] [Revised: 06/03/2015] [Accepted: 06/09/2015] [Indexed: 12/20/2022]
Abstract
Human noroviruses (NoV) are the leading cause of acute viral gastroenteritis worldwide. Significant antigenic diversity of NoV strains has limited the availability of broadly reactive ligands for design of detection assays. The purpose of this work was to produce and characterize single stranded (ss)DNA aptamers with binding specificity to human NoV using an easily produced NoV target-the P domain protein. Aptamer selection was done using SELEX (Systematic Evolution of Ligands by EXponential enrichment) directed against an Escherichia coli-expressed and purified epidemic NoV GII.4 strain P domain. Two of six unique aptamers (designated M1 and M6-2) were chosen for characterization. Inclusivity testing using an enzyme-linked aptamer sorbent assay (ELASA) against a panel of 14 virus-like particles (VLPs) showed these aptamers had broad reactivity and exhibited strong binding to GI.7, GII.2, two GII.4 strains, and GII.7 VLPs. Aptamer M6-2 exhibited at least low to moderate binding to all VLPs tested. Aptamers significantly (p<0.05) bound virus in partially purified GII.4 New Orleans outbreak stool specimens as demonstrated by ELASA and aptamer magnetic capture (AMC) followed by RT-qPCR. This is the first demonstration of human NoV P domain protein as a functional target for the selection of nucleic acid aptamers that specifically bind and broadly recognize diverse human NoV strains.
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Affiliation(s)
- Matthew D Moore
- Department of Food, Bioprocessing and Nutrition Sciences, North Carolina State University, 315 Schaub Hall, 400 Dan Allen Drive, Raleigh, NC 27695, USA.
| | - Blanca I Escudero-Abarca
- Department of Food, Bioprocessing and Nutrition Sciences, North Carolina State University, 315 Schaub Hall, 400 Dan Allen Drive, Raleigh, NC 27695, USA
| | - Soo Hwan Suh
- Department of Food, Bioprocessing and Nutrition Sciences, North Carolina State University, 315 Schaub Hall, 400 Dan Allen Drive, Raleigh, NC 27695, USA
| | - Lee-Ann Jaykus
- Department of Food, Bioprocessing and Nutrition Sciences, North Carolina State University, 315 Schaub Hall, 400 Dan Allen Drive, Raleigh, NC 27695, USA
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Abstract
Sapoviruses cause acute gastroenteritis in humans and animals. They belong to the genus Sapovirus within the family Caliciviridae. They infect and cause disease in humans of all ages, in both sporadic cases and outbreaks. The clinical symptoms of sapovirus gastroenteritis are indistinguishable from those caused by noroviruses, so laboratory diagnosis is essential to identify the pathogen. Sapoviruses are highly diverse genetically and antigenically. Currently, reverse transcription-PCR (RT-PCR) assays are widely used for sapovirus detection from clinical specimens due to their high sensitivity and broad reactivity as well as the lack of sensitive assays for antigen detection or cell culture systems for the detection of infectious viruses. Sapoviruses were first discovered in 1976 by electron microscopy in diarrheic samples of humans. To date, sapoviruses have also been detected from several animals: pigs, mink, dogs, sea lions, and bats. In this review, we focus on genomic and antigenic features, molecular typing/classification, detection methods, and clinical and epidemiological profiles of human sapoviruses.
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31
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Application of salivary antibody immunoassays for the detection of incident infections with Norwalk virus in a group of volunteers. J Immunol Methods 2015; 424:53-63. [PMID: 25985985 DOI: 10.1016/j.jim.2015.05.001] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2015] [Revised: 04/23/2015] [Accepted: 05/06/2015] [Indexed: 02/06/2023]
Abstract
Norovirus infection is the most common cause of acute gastroenteritis in developed countries. Developing an assay based on a non-invasive biomarker for detecting incident norovirus infections could improve disease surveillance and epidemiological investigations. This project involved analysis of IgA and IgG norovirus-specific antibody responses in saliva samples from a Norwalk virus (Genogroup I, genotype 1 norovirus) challenge study involving infected and symptomatic, and non-infected asymptomatic individuals. Saliva was collected at the challenge, and two weeks and 40 days post-challenge. Samples were analyzed using the Luminex fluorometric and Meso Scale Discovery (MSD) electrochemiluminescence immunoassays. Recombinant P domains of Norwalk virus capsid protein, as well as similar recombinant proteins of two genogroup II noroviruses (VA387 and VA207) were used as antigens. Immunoconversions were defined as >4-fold increase in antibody responses to the norovirus antigens. Various sample pre-treatment options, buffers, saliva dilution ratios, and data adjustment approaches to control for sample-to-sample variability in saliva composition were compared using the Luminex assay. The results suggest that adjusting responses to the norovirus antigens for responses to the protein purification tag, glutathione-S-transferase (GST), significantly improved the odds of producing a correct immunoconversion test result. IgG-based tests were more accurate compared to IgA-based tests. At optimal conditions, both Luminex and MSD assays for Norwalk-specific IgG antibodies correctly identified all infected and non-infected individuals. There was no evidence of cross-reactivity of anti-Norwalk virus antibodies with genogroup II noroviruses. These results suggest that salivary antibody responses can be used for the detection of incident infections with Norwalk virus in prospective surveys.
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Kou B, Crawford SE, Ajami NJ, Czakó R, Neill FH, Tanaka TN, Kitamoto N, Palzkill TG, Estes MK, Atmar RL. Characterization of cross-reactive norovirus-specific monoclonal antibodies. CLINICAL AND VACCINE IMMUNOLOGY : CVI 2015; 22:160-7. [PMID: 25428247 PMCID: PMC4308874 DOI: 10.1128/cvi.00519-14] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/30/2014] [Accepted: 11/14/2014] [Indexed: 12/13/2022]
Abstract
Noroviruses (NoVs) commonly cause acute gastroenteritis outbreaks. Broadly reactive diagnostic assays are essential for rapid detection of NoV infections. We previously generated a panel of broadly reactive monoclonal antibodies (MAbs). We characterized MAb reactivities by use of virus-like particles (VLPs) from 16 different NoV genotypes (6 from genogroup I [GI], 9 from GII, and 1 from GIV) coating a microtiter plate (direct enzyme-linked immunosorbent assay [ELISA]) and by Western blotting. MAbs were genotype specific or recognized multiple genotypes within a genogroup and between genogroups. We next applied surface plasmon resonance (SPR) analysis to measure MAb dissociation constants (Kd) as a surrogate for binding affinity; a Kd level of <10 nM was regarded as indicating strong binding. Some MAbs did not interact with the VLPs by SPR analysis. To further assess this lack of MAb-VLP interaction, the MAbs were evaluated for the ability to identify NoV VLPs in a capture ELISA. Those MAbs for which a Kd could not be measured by SPR analysis also failed to capture the NoV VLPs; in contrast, those with a measurable Kd gave a positive signal in the capture ELISA. Thus, some broadly cross-reactive epitopes in the VP1 protruding domain may be partially masked on intact particles. One MAb, NV23, was able to detect genogroup I, II, and IV VLPs from 16 genotypes tested by sandwich ELISA, and it successfully detected NoVs in stool samples positive by real-time reverse transcription-PCR when the threshold cycle (CT) value was <31. Biochemical analyses of MAb reactivity, including SPR analysis, identified NV23 as a broadly reactive ligand for application in norovirus diagnostic assays.
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Affiliation(s)
- Baijun Kou
- Department of Molecular Virology and Microbiology, Baylor College of Medicine, Houston, Texas, USA
| | - Sue E Crawford
- Department of Molecular Virology and Microbiology, Baylor College of Medicine, Houston, Texas, USA
| | - Nadim J Ajami
- Department of Molecular Virology and Microbiology, Baylor College of Medicine, Houston, Texas, USA
| | - Rita Czakó
- Department of Molecular Virology and Microbiology, Baylor College of Medicine, Houston, Texas, USA
| | - Frederick H Neill
- Department of Molecular Virology and Microbiology, Baylor College of Medicine, Houston, Texas, USA
| | | | - Noritoshi Kitamoto
- Department of Food Science and Nutrition, Himeji College of Hyogo, Himeji, Japan
| | - Timothy G Palzkill
- Department of Molecular Virology and Microbiology, Baylor College of Medicine, Houston, Texas, USA Department of Pharmacology, Baylor College of Medicine, Houston, Texas, USA
| | - Mary K Estes
- Department of Molecular Virology and Microbiology, Baylor College of Medicine, Houston, Texas, USA Department of Medicine, Baylor College of Medicine, Houston, Texas, USA
| | - Robert L Atmar
- Department of Molecular Virology and Microbiology, Baylor College of Medicine, Houston, Texas, USA Department of Medicine, Baylor College of Medicine, Houston, Texas, USA
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Abstract
UNLABELLED Human noroviruses are icosahedral single-stranded RNA viruses. The capsid protein is divided into shell (S) and protruding (P) domains, which are connected by a flexible hinge region. There are numerous genetically and antigenically distinct noroviruses, and the dominant strains evolve every other year. Vaccine and antiviral development is hampered by the difficulties in growing human norovirus in cell culture and the continually evolving strains. Here, we show the X-ray crystal structures of human norovirus P domains in complex with two different nanobodies. One nanobody, Nano-85, was broadly reactive, while the other, Nano-25, was strain specific. We showed that both nanobodies bound to the lower region on the P domain and had nanomolar affinities. The Nano-85 binding site mainly comprised highly conserved amino acids among the genetically distinct genogroup II noroviruses. Several of the conserved residues also were recognized by a broadly reactive monoclonal antibody, which suggested this region contained a dominant epitope. Superposition of the P domain nanobody complex structures into a cryoelectron microscopy particle structure revealed that both nanobodies bound at occluded sites on the particles. The flexible hinge region, which contained ~10 to 12 amino acids, likely permitted a certain degree of P domain movement on the particles in order to accommodate the nanobodies. Interestingly, the Nano-85 binding interaction with intact particles caused the particles to disassemble in vitro. Altogether, these results suggested that the highly conserved Nano-85 binding epitope contained a trigger mechanism for particle disassembly. Principally, this epitope represents a potential site of norovirus vulnerability. IMPORTANCE We characterized two different nanobodies (Nano-85 and Nano-25) that bind to human noroviruses. Both nanobodies bound with high affinities to the lower region of the P domain, which was occluded on intact particles. Nano-25 was specific for GII.10, whereas Nano-85 bound several different GII genotypes, including GII.4, GII.10, and GII.12. We showed that Nano-85 was able to detect norovirus virions in clinical stool specimens using a sandwich enzyme-linked immunosorbent assay. Importantly, we found that Nano-85 binding to intact particles caused the particles to disassemble. We believe that with further testing, Nano-85 not only will work as a diagnostic reagent in norovirus detection systems but also could function as a broadly reactive GII norovirus antiviral.
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Mapping broadly reactive norovirus genogroup I and II monoclonal antibodies. CLINICAL AND VACCINE IMMUNOLOGY : CVI 2014; 22:168-77. [PMID: 25428246 DOI: 10.1128/cvi.00520-14] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Noroviruses are responsible for most acute nonbacterial epidemic outbreaks of gastroenteritis worldwide. To develop cross-reactive monoclonal antibodies (MAbs) for rapid identification of genogroup I and II (GI and GII) noroviruses (NoVs) in field specimens, mice were immunized with baculovirus-expressed recombinant virus-like particles (VLPs) corresponding to NoVs. Nine MAbs against the capsid protein were identified that detected both GI and GII NoV VLPs. These MAbs were tested in competition enzyme-linked immunosorbent assays (ELISAs) to identify common epitope reactivities to GI and GII VLPs. Patterns of competitive reactivity placed these MAbs into two epitope groups (groups 1 and 2). Epitopes for MAbs NV23 and NS22 (group 1) and MAb F120 (group 2) were mapped to a continuous region in the C-terminal P1 subdomain of the capsid protein. This domain is within regions previously defined to contain cross-reactive epitopes in GI and GII viruses, suggesting that common epitopes are clustered within the P1 domain of the capsid protein. Further characterization in an accompanying paper (B. Kou et al., Clin Vaccine Immunol 22:160-167, 2015, http://dx.doi.org/10.1128/CVI.00519-14) revealed that MAb NV23 (epitope group 1) is able to detect GI and GII viruses in stool. Inclusion of the GI and GII cross-reactive MAb NV23 in antigen detection assays may facilitate the identification of GI and GII human noroviruses in stool samples as causative agents of outbreaks and sporadic cases of gastroenteritis worldwide.
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Huang W, Samanta M, Crawford SE, Estes MK, Neill FH, Atmar RL, Palzkill T. Identification of human single-chain antibodies with broad reactivity for noroviruses. Protein Eng Des Sel 2014; 27:339-49. [PMID: 24946948 PMCID: PMC4191442 DOI: 10.1093/protein/gzu023] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2013] [Revised: 04/19/2014] [Accepted: 05/23/2014] [Indexed: 11/14/2022] Open
Abstract
Norovirus infections are a common cause of gastroenteritis and new methods to rapidly diagnose norovirus infections are needed. The goal of this study was to identify antibodies that have broad reactivity of binding to various genogroups of norovirus. A human scFv phage display library was used to identify two antibodies, HJT-R3-A9 and HJT-R3-F7, which bind to both genogroups I and II norovirus virus-like particles (VLPs). Mapping experiments indicated that the HJT-R3-A9 clone binds to the S-domain while the HJT-R3-F7 clone binds the P-domain of the VP1 capsid protein. In addition, a family of scFv antibodies was identified by elution of phage libraries from the GII.4 VLP target using a carbohydrate that serves as an attachment factor for norovirus on human cells. These antibodies were also found to recognize both GI and GII VLPs in enzyme-linked immunosorbent assay (ELISA) experiments. The HJT-R3-A9, HJT-R3-F7 and scFv antibodies identified with carbohydrate elution were shown to detect antigen from a clinical sample known to contain GII.4 norovirus but not a negative control sample. Finally, phages displaying the HJT-R3-A9 scFv can be used directly to detect both GI.1 and GII.4 norovirus from stool samples, which has the potential to simplify and reduce the cost of diagnostics based on antibody-based ELISA methods.
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Affiliation(s)
- Wanzhi Huang
- Department of Pharmacology, Baylor College of Medicine, Houston, TX, USA
| | - Moumita Samanta
- Department of Pharmacology, Baylor College of Medicine, Houston, TX, USA
| | - Sue E Crawford
- Department of Molecular Virology and Microbiology, Baylor College of Medicine, Houston, TX, USA
| | - Mary K Estes
- Department of Molecular Virology and Microbiology, Baylor College of Medicine, Houston, TX, USA Department of Medicine, Baylor College of Medicine, Houston, TX, 77030, USA
| | - Frederick H Neill
- Department of Molecular Virology and Microbiology, Baylor College of Medicine, Houston, TX, USA
| | - Robert L Atmar
- Department of Molecular Virology and Microbiology, Baylor College of Medicine, Houston, TX, USA Department of Medicine, Baylor College of Medicine, Houston, TX, 77030, USA
| | - Timothy Palzkill
- Department of Pharmacology, Baylor College of Medicine, Houston, TX, USA Department of Molecular Virology and Microbiology, Baylor College of Medicine, Houston, TX, USA
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Farkas T, Lun CWP, Fey B. Relationship between genotypes and serotypes of genogroup 1 recoviruses: a model for human norovirus antigenic diversity. J Gen Virol 2014; 95:1469-1478. [PMID: 24700099 PMCID: PMC4059267 DOI: 10.1099/vir.0.064675-0] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023] Open
Abstract
Human norovirus (NoV) research greatly relies on cell culture-propagable surrogate caliciviruses, including murine NoVs and the prototype 'recovirus' (ReCV), Tulane virus. However, the extreme biological diversity of human NoVs cannot be modelled by a uniform group of viruses or single isolate. Based on a diverse group of recently described ReCVs, a more advanced model reflecting human NoV biological diversity is currently under development. Here, we have reported the genotypic and serotypic relationships among 10 G1 ReCV isolates, including Tulane virus and nine other recent cell culture-adapted strains. Based on the amino acid sequences of virus capsid protein, VP1, and classification constraints established for NoVs, G1 ReCVs were separated into three genotypes, with variable organization of the three open reading frames. Interestingly, cross-neutralization plaque assays revealed the existence of four distinct serotypes, two of which were detected among the G1.2 strains. The amino acid (aa) difference between the two G1.2 ReCV serotypes (12%) was less than the minimum 13% difference established between NoV genotypes. Interestingly, one of the G1.3 ReCVs was equally neutralized by antisera raised against the G1.3 (6% aa difference) and G1.1 (25% aa difference) representative strains. These results imply the existence of a large number of human NoV serotypes, but also shared cross-neutralization epitopes between some strains of different genotypes. In conclusion, the newly developed ReCV surrogate model can be applied to address biologically relevant questions pertaining to enteric CV diversity.
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Affiliation(s)
- Tibor Farkas
- University of Cincinnati College of Medicine, Cincinnati, OH, USA
- Cincinnati Children's Hospital Medical Center, OH, USA
| | | | - Brittney Fey
- Cincinnati Children's Hospital Medical Center, OH, USA
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Kolawole AO, Xia C, Li M, Gamez M, Yu C, Rippinger CM, Yucha RE, Smith TJ, Wobus CE. Newly isolated mAbs broaden the neutralizing epitope in murine norovirus. J Gen Virol 2014; 95:1958-1968. [PMID: 24899153 DOI: 10.1099/vir.0.066753-0] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Here, we report the isolation and functional characterization of mAbs against two murine norovirus (MNV) strains, MNV-1 and WU20, which were isolated following oral infection of mice. The mAbs were screened for reactivity against the respective homologous and heterologous MNV strain by ELISA. Selected mAbs were of IgA, IgG1, IgG2a or IgG2b isotype and showed a range of Western blot reactivities from non-binding to strong binding, suggesting recognition of conformational and linear epitopes. Some of the anti-MNV-1 antibodies neutralized both MNV-1 and WU20 infections in culture and in mice, but none of the anti-WU20 mAbs neutralized either virus. The non-neutralizing anti-MNV-1 IgG2b antibody 5C4.10 was mapped to the S domain of the MNV-1 capsid, whilst the epitopes of the neutralizing anti-MNV-1 IgA antibodies 2D3.7 and 4F9.4 were mapped to the P domain. Generation of neutralization escape viruses showed that two mutations (V339I and D348E) in the C'D' loop of the MNV-1 P domain mediated escape from mAb 2D3.7 and 4F9.4 neutralization. These findings broaden the known neutralizing epitopes of MNV to the main surface-exposed loops of the P domain. In addition, the current panel of antibodies provides valuable reagents for studying norovirus biology and development of diagnostic tools.
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Affiliation(s)
- Abimbola O Kolawole
- Department of Microbiology and Immunology, University of Michigan Medical School, Ann Arbor, MI, USA
| | - Chunsheng Xia
- Donald Danforth Plant Science Center, St Louis, MO, USA
| | - Ming Li
- Donald Danforth Plant Science Center, St Louis, MO, USA
| | - Monica Gamez
- Department of Microbiology and Immunology, University of Michigan Medical School, Ann Arbor, MI, USA
| | - Chenchen Yu
- Department of Microbiology and Immunology, University of Michigan Medical School, Ann Arbor, MI, USA
| | - Christine M Rippinger
- Department of Microbiology and Immunology, University of Michigan Medical School, Ann Arbor, MI, USA
| | - Ryan E Yucha
- Department of Microbiology and Immunology, University of Michigan Medical School, Ann Arbor, MI, USA
| | | | - Christiane E Wobus
- Department of Microbiology and Immunology, University of Michigan Medical School, Ann Arbor, MI, USA
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Temporal dynamics of norovirus GII.4 variants in Brazil between 2004 and 2012. PLoS One 2014; 9:e92988. [PMID: 24667283 PMCID: PMC3965504 DOI: 10.1371/journal.pone.0092988] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2013] [Accepted: 02/27/2014] [Indexed: 01/01/2023] Open
Abstract
Noroviruses (NoVs) are the major cause of acute gastroenteritis outbreaks, and, despite a wide genetic diversity, genotype II.4 is the most prevalent strain worldwide. Mutations and homologous recombination have been proposed as mechanisms driving the epochal evolution of the GII.4, with the emergence of new variants in 1–3-year intervals causing global epidemics. There are no data reporting the dynamics of GII.4 variants along a specific period in Brazil. Therefore, to improve the understanding of the comportment of these variants in the country, the aim of this study was to evaluate the circulation of NoV GII.4 variants during a 9-year period in 3 out of 5 Brazilian regions. A total of 147 samples were sequenced, and a phylogenetic analysis of subdomain P2 demonstrated the circulation of six GII.4 variants, Asia_2003, Hunter_2004, Den Haag_2006b, Yerseke_2006a, New Orleans_2009, and Sydney_2012, during this period. The most prevalent variant was Den Haag_2006b, circulating in different Brazilian regions from 2006 to 2011. A Bayesian coalescent analysis was used to calculate the mean evolutionary rate of subdomain P2 as 7.3×10−3 (5.85×10−3–8.82×10−3) subst./site/year. These analyses also demonstrated that clade Den Haag_2006b experienced a rapid expansion in 2005 and another in 2008 after a period of decay. The evaluation of the temporal dynamics of NoV GII.4 in Brazil revealed a similar pattern, with few exceptions, to the worldwide observation. These data highlight the importance of surveillance for monitoring the emergence of new strains of NoV GII.4 and its impact on cases of acute gastroenteritis.
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Identification and characterization of antibody-binding epitopes on the norovirus GII.3 capsid. J Virol 2013; 88:1942-52. [PMID: 24284328 DOI: 10.1128/jvi.02992-13] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023] Open
Abstract
Genotype II.3 (GII.3) noroviruses are a major cause of sporadic gastroenteritis, particularly in children. The greater incidence of GII.3 noroviruses in the pediatric population compared to the adult demographic suggests development of herd immunity to this genotype, possibly as a consequence of limited evolution of immune epitopes. This study aimed to identify and characterize immune epitopes on the GII.3 capsid protein and to determine the level of immune cross-reactivity within the genotype. A panel of seven GII.3 virus-like particles (VLPs), representing norovirus strains isolated during 1975 to 2008, was tested by enzyme-linked immunosorbent assay (ELISA) for reactivity with human sera and a rabbit anti-GII.3 strain-specific polyclonal serum generated against the 2008 GII.3 VLP. Immunoprecipitation of protease-digested GII.3 VLPs and sequencing of bound peptides via mass spectrometry were used to locate epitopes on the capsid. Two epitopes were investigated further using Mimotopes technology. Serum binding studies demonstrated complete intragenotype GII.3 cross-reactivity using both human and rabbit serum. Six immunoreactive regions containing epitopes were located on the GII.3 capsid protein, two within each capsid domain. Epitopes in the S and P1 domains were highly conserved within GII.3 noroviruses. P2 domain epitopes were variable and contained evolutionarily important residues and histo-blood group antigen (HBGA) binding residues. In conclusion, anti-GII.3 antibody-binding epitopes are highly cross-reactive and mostly conserved within GII.3 strains. This may account for the limited GII.3 prevalence in adults and suggests that a GII.3 strain may be a valuable inclusion in a multivalent pediatric targeted VLP vaccine. Exploration of norovirus immune epitopes is vital for effective vaccine design. IMPORTANCE This study represents an important contribution to the understanding of norovirus immunology in a pediatric genotype. The high cross-reactivity and conservation of GII.3 epitopes suggest development of herd immunity against GII.3 and indicate that a GII.3 strain would be a valuable inclusion in a pediatric targeted multivalent vaccine. Immunological understanding of pediatric norovirus strains is important since norovirus vaccines will likely target high-risk groups such as the pediatric population.
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Higo-Moriguchi K, Shirato H, Someya Y, Kurosawa Y, Takeda N, Taniguchi K. Isolation of cross-reactive human monoclonal antibodies that prevent binding of human noroviruses to histo-blood group antigens. J Med Virol 2013; 86:558-67. [DOI: 10.1002/jmv.23734] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 07/08/2013] [Indexed: 11/08/2022]
Affiliation(s)
- Kyoko Higo-Moriguchi
- Department of Virology and Parasitology; Fujita Health University School of Medicine; Toyoake Aichi Japan
| | - Haruko Shirato
- Department of Virology II; National Institute of Infectious Diseases; Musashi-Murayama Tokyo Japan
| | - Yuichi Someya
- Department of Virology II; National Institute of Infectious Diseases; Musashi-Murayama Tokyo Japan
| | - Yoshikazu Kurosawa
- Institute for Comprehensive Medical Science; Fujita Health University School of Medicine; Toyoake Aichi Japan
| | - Naokazu Takeda
- Department of Virology II; National Institute of Infectious Diseases; Musashi-Murayama Tokyo Japan
| | - Koki Taniguchi
- Department of Virology and Parasitology; Fujita Health University School of Medicine; Toyoake Aichi Japan
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Abstract
Human noroviruses (HuNoVs) cause significant morbidity and mortality worldwide. However, despite substantial efforts, a small-animal model for HuNoV has not been described to date. Since “humanized” mice have been successfully used to study human-tropic pathogens in the past, we challenged BALB/c mice deficient in recombination activation gene (Rag) 1 or 2 and common gamma chain (γc) (Rag-γc) engrafted with human CD34+ hematopoietic stem cells, nonengrafted siblings, and immunocompetent wild-type controls with pooled stool isolates from patients positive for HuNoV. Surprisingly, both humanized and nonhumanized BALB/c Rag-γc-deficient mice supported replication of a GII.4 strain of HuNoV, as indicated by increased viral loads over input. In contrast, immunocompetent wild-type BALB/c mice were not infected. An intraperitoneal route of infection and the BALB/c genetic background were important for facilitating a subclinical HuNoV infection of Rag-γc-deficient mice. Expression of structural and nonstructural proteins was detected in cells with macrophage-like morphology in the spleens and livers of BALB/c Rag-γc-deficient mice, confirming the ability of HuNoV to replicate in a mouse model. In summary, HuNoV replication in BALB/c Rag-γc-deficient mice is dependent on the immune-deficient status of the host but not on the presence of human immune cells and provides the first genetically manipulable small-animal model for studying HuNoV infection. Human noroviruses are a significant cause of viral gastroenteritis worldwide, resulting in significant morbidity and mortality. Antivirals and vaccines are currently not available, in part due to the inability to study these viruses in a genetically manipulable, small-animal model. Herein, we report the first mouse model for human noroviruses. This model will accelerate our understanding of human norovirus biology and provide a useful resource for evaluating antiviral therapies.
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Parra GI, Azure J, Fischer R, Bok K, Sandoval-Jaime C, Sosnovtsev SV, Sander P, Green KY. Identification of a Broadly Cross-Reactive Epitope in the Inner Shell of the Norovirus Capsid. PLoS One 2013; 8:e67592. [PMID: 23805319 PMCID: PMC3689733 DOI: 10.1371/journal.pone.0067592] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2013] [Accepted: 05/20/2013] [Indexed: 12/12/2022] Open
Abstract
Noroviruses are major pathogens associated with acute gastroenteritis. They are diverse viruses, with at least six genogroups (GI-GVI) and multiple genotypes defined by differences in the major capsid protein, VP1. This diversity has challenged the development of broadly cross-reactive vaccines as well as efficient detection methods. Here, we report the characterization of a broadly cross-reactive monoclonal antibody (MAb) raised against the capsid protein of a GII.3 norovirus strain. The MAb reacted with VLPs and denatured VP1 protein from GI, GII, GIV and GV noroviruses, and mapped to a linear epitope located in the inner shell domain. An alignment of all available VP1 sequences showed that the putative epitope (residues 52–56) is highly conserved across the genus Norovirus. This broadly cross-reactive MAb thus constitutes a valuable reagent for the diagnosis and study of these diverse viruses.
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Affiliation(s)
- Gabriel I. Parra
- Caliciviruses Section, Laboratory of Infectious Diseases, National Institute of Allergy and Infectious Diseases, National Institutes of Health, DHHS, Bethesda, Maryland, United States of America
- * E-mail: (KYG); (GIP)
| | - JoLynn Azure
- Caliciviruses Section, Laboratory of Infectious Diseases, National Institute of Allergy and Infectious Diseases, National Institutes of Health, DHHS, Bethesda, Maryland, United States of America
| | | | - Karin Bok
- Caliciviruses Section, Laboratory of Infectious Diseases, National Institute of Allergy and Infectious Diseases, National Institutes of Health, DHHS, Bethesda, Maryland, United States of America
| | - Carlos Sandoval-Jaime
- Caliciviruses Section, Laboratory of Infectious Diseases, National Institute of Allergy and Infectious Diseases, National Institutes of Health, DHHS, Bethesda, Maryland, United States of America
| | - Stanislav V. Sosnovtsev
- Caliciviruses Section, Laboratory of Infectious Diseases, National Institute of Allergy and Infectious Diseases, National Institutes of Health, DHHS, Bethesda, Maryland, United States of America
| | - Peter Sander
- Clinical Diagnostics, R-Biopharm AG, Darmstadt, Germany
| | - Kim Y. Green
- Caliciviruses Section, Laboratory of Infectious Diseases, National Institute of Allergy and Infectious Diseases, National Institutes of Health, DHHS, Bethesda, Maryland, United States of America
- * E-mail: (KYG); (GIP)
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Vongpunsawad S, Venkataram Prasad BV, Estes MK. Norwalk Virus Minor Capsid Protein VP2 Associates within the VP1 Shell Domain. J Virol 2013; 87:4818-25. [PMID: 23408637 PMCID: PMC3624303 DOI: 10.1128/jvi.03508-12] [Citation(s) in RCA: 96] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2012] [Accepted: 02/08/2013] [Indexed: 11/20/2022] Open
Abstract
The major capsid protein of norovirus VP1 assembles to form an icosahedral viral particle. Despite evidence that the Norwalk virus (NV) minor structural protein VP2 is present in infectious virions, the available crystallographic and electron cryomicroscopy structures of NV have not revealed the location of VP2. In this study, we determined that VP1 associates with VP2 at the interior surface of the capsid, specifically with the shell (S) domain of VP1. We mapped the interaction site to amino acid 52 of VP1, an isoleucine located within a sequence motif IDPWI in the S domain that is highly conserved across norovirus genogroups. Mutation of this isoleucine abrogated VP2 incorporation into virus-like particles without affecting the ability for VP1 to dimerize and form particles. The highly basic nature of VP2 and its location interior to the viral particle are consistent with its potential role in assisting capsid assembly and genome encapsidation.
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Affiliation(s)
| | - B. V. Venkataram Prasad
- Department of Molecular Virology and Microbiology
- Verna and Marrs McLean Department of Biochemistry and Molecular Biology, Baylor College of Medicine, Houston, Texas, USA
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Identification and characterization of a peptide affinity reagent for detection of noroviruses in clinical samples. J Clin Microbiol 2013; 51:1803-8. [PMID: 23554202 DOI: 10.1128/jcm.00295-13] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
Norovirus (NoV) is the most common agent of nonbacterial epidemic gastroenteritis and is estimated to cause 21 million cases of the disease in the United States annually. The antigen enzyme-linked immunosorbent assays (ELISAs) currently available for NoV diagnosis detect only certain strains and are approved for use in the United States only in epidemics where NoV is suspected. There is a clear need for simpler, more rapid, and more reliable diagnostic tools for the detection of NoV. In this study, phage display technology was used to screen a library of phage displaying random 12-mer peptides for those that bind to Norwalk virus virus-like particles (NV VLPs). Three phage clones displaying unique peptides were identified, and both the peptide-displaying phages and the peptides were confirmed to bind specifically to NV VLPs. The peptide displayed on phage clone NV-N-R5-1 was determined to bind to the protruding domain of the VP1 capsid protein. This phage also bound to NV VLPs seeded into NoV-negative stool with a limit of detection of 1.56 ng NV VLP. This value was comparable to monoclonal antibody (MAb) 3912, which is currently used in commercially available assays. Furthermore, the NV-N-R5-1 phage exhibited high specificity by detecting NV only in previously characterized NV-positive stool samples in contrast to no detection in NV-negative stool samples. These data demonstrate that the further development of NV-N-R5-1 phage as a diagnostic reagent is possible and might offer several distinct advantages over antibodies, such as decreases in the time and cost of production and ease of isolating phage against other epidemic strains currently circulating as well as those that are emerging.
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Abstract
Norovirus (NoV) is the leading cause of viral gastroenteritis globally. Since 1996, NoV variants of a single genetic lineage, GII.4, have been associated with at least six pandemics of acute gastroenteritis and caused between 62 and 80% of all NoV outbreaks. The emergence of these novel GII.4 variants has been attributed to rapid evolution and antigenic variation in response to herd immunity; however, the contribution of recombination as a mechanism facilitating emergence is increasingly evident. In this study, we sought to examine the role that intragenotype recombination has played in the emergence of GII.4 variants. Using a genome-wide approach including 25 complete genome sequences generated as part of this study, 11 breakpoints were identified within the NoV GII.4 lineage. The breakpoints were located at three recombination hot spots: near the open reading frame 1/2 (ORF1/2) and ORF2/3 overlaps, as well as within ORF2, which encodes the viral capsid, at the junction of the shell and protruding domains. Importantly, we show that recombination contributed to the emergence of the recent pandemic GII.4 variant, New Orleans 2009, and a newly identified GII.4 variant, termed Sydney 2012. Reconstructing the evolutionary history of the GII.4 lineage reveals the widespread impact of both inter- and intragenotype recombination on the emergence of many GII.4 variants. Lastly, this study highlights the many challenges in the identification of true recombination events and proposes that guidelines be applied for identifying NoV recombinants.
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Kitamoto N, Oka T, Katayama K, Li TC, Takeda N, Kato Y, Miyoshi T, Tanaka T. Novel monoclonal antibodies broadly reactive to human recombinant sapovirus-like particles. Microbiol Immunol 2013; 56:760-70. [PMID: 22924483 DOI: 10.1111/j.1348-0421.2012.00499.x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
Sapovirus (SaV), a member of the family Caliciviridae, is an important cause of acute epidemic gastroenteritis in humans. Human SaV is genetically and antigenically diverse and can be classified into four genogroups (GI, GII, GIV, and GV) and 16 genotypes (7 GI [GI.1-7], 7 GII, [GII.1-7], 1 GIV and 1 GV), based on capsid sequence similarities. Monoclonal antibodies (MAbs) are powerful tools for examining viruses and proteins. PAI myeloma cells were fused with spleen cells from mice immunized with a single type of recombinant human SaV virus-like particles (VLPs) (GI.1, GI.5, GI.6, GII.3, GIV, or GV). Sixty-five hybrid clones producing MAbs were obtained. Twenty-four MAbs were characterized by ELISA, according to their cross-reactivity to each VLP (GI.1, GI.5, GI.6, GII.2, GII.3, GII.4, GII.7, GIV, and GV). The MAbs were classified by this method into: (i) MAbs broadly cross-reactive to all GI, GII, GIV and GV strains; (ii) those reactive in a genogroup-specific; and (iii) those reactive in a genotype-specific manner. Further analysis of three broadly cross-reactive MAbs with a competitive ELISA demonstrated that at least two different common epitopes are located on the capsid protein of human SaVs in the four genogroups. The MAbs generated and characterized in this study will be useful tools for further study of the antigenic and structural topography of the human SaV virion and for developing new diagnostic assays for human SaV.
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Affiliation(s)
- Noritoshi Kitamoto
- School of Human Science and Environment, University of Hyogo, Hyogo 670-0092, Japan.
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Affiliation(s)
- Kari Debbink
- Department of Microbiology and Immunology, School of Medicine, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, United States of America
| | - Lisa C. Lindesmith
- Department of Epidemiology, Gillings School of Global Public Health, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, United States of America
| | - Eric F. Donaldson
- Department of Epidemiology, Gillings School of Global Public Health, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, United States of America
| | - Ralph S. Baric
- Department of Microbiology and Immunology, School of Medicine, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, United States of America
- Department of Epidemiology, Gillings School of Global Public Health, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, United States of America
- * E-mail:
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Bioluminescent enzyme immunoassay for the detection of norovirus capsid antigen. CLINICAL AND VACCINE IMMUNOLOGY : CVI 2012; 19:1949-54. [PMID: 23081816 DOI: 10.1128/cvi.00427-12] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
An ultrasensitive and fully automated bioluminescent enzyme immunoassay (BLEIA) was developed for the detection of norovirus (NV) capsid antigen. In the evaluation tests with recombinant virus-like particles, the BLEIA demonstrated broad reactivity against several NV genotypes (genotypes 1, 3, 4, 7, 8, and 12 in genogroup I [GI] and genotypes 1, 2, 3, 4, 5, 6, 12, and 13 in GII), a wide dose-response range from 0.25 pg/ml to 10,000 pg/ml, and good reproducibility with low coefficients of variation (CVs) (within-run CVs of <2.8%, between-day CVs of <3.7%). In the evaluation tests with NV-positive fecal samples, a good correlation (y = 0.66x - 3.21, r = 0.84) between the BLEIA and real-time quantitative reverse transcription-PCR was obtained. Furthermore, in the dilution test with NV specimens, the analytical sensitivity of NV was estimated to be 10(5) to 10(6) copies/g of fecal sample, indicating that the analytical sensitivity of the BLEIA is comparable to that of commercially available molecular methods. All assay steps are fully automated, the turnaround time is 46 min, and the throughput of the assay is 120 tests/h. These results indicate that the BLEIA is potentially useful for the rapid diagnosis of NV in epidemic and sporadic gastroenteritis.
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Sharp TM, Crawford SE, Ajami NJ, Neill FH, Atmar RL, Katayama K, Utama B, Estes MK. Secretory pathway antagonism by calicivirus homologues of Norwalk virus nonstructural protein p22 is restricted to noroviruses. Virol J 2012; 9:181. [PMID: 22943503 PMCID: PMC3493335 DOI: 10.1186/1743-422x-9-181] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2011] [Accepted: 08/22/2012] [Indexed: 11/25/2022] Open
Abstract
Background Our previous report that the Norwalk virus nonstructural protein p22 is an antagonist of the cellular secretory pathway suggests a new aspect of norovirus/host interaction. To explore conservation of function of this highly divergent calicivirus protein, we examined the effects of p22 homologues from four human and two murine noroviruses, and feline calicivirus on the secretory pathway. Findings All human noroviruses examined induced Golgi disruption and inhibited protein secretion, with the genogroup II.4 Houston virus being the most potent antagonist. Genogroup II.6 viruses have a conserved mutation in the mimic of an Endoplasmic Reticulum export signal (MERES) motif that is highly conserved in human norovirus homologues of p22 and is critical for secretory pathway antagonism, and these viruses had reduced levels of Golgi disruption and inhibition of protein secretion. p22 homologues from both persistent and nonpersistent strains of murine norovirus induced Golgi disruption, but only mildly inhibited cellular protein secretion. Feline calicivirus p30 did not induce Golgi disruption or inhibit cellular protein secretion. Conclusions These differences confirm a norovirus-specific effect on host cell secretory pathway antagonism by homologues of p22, which may affect viral replication and/or cellular pathogenesis.
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Affiliation(s)
- Tyler M Sharp
- Department of Molecular Virology and Microbiology, Baylor College of Medicine, Houston, TX 77030, USA
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