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Wongsa A, Priengprom T, Saelee J, Phawong C, Tassaneetrithep B. Development of a high-throughput flow cytometric neutralization assay to screen for human enterovirus A71 (EVA71) neutralizing antibodies. J Virol Methods 2023; 322:114828. [PMID: 37778536 DOI: 10.1016/j.jviromet.2023.114828] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2023] [Revised: 09/26/2023] [Accepted: 09/29/2023] [Indexed: 10/03/2023]
Abstract
The conventional method for screening neutralizing antibodies to human enterovirus A71 (EVA71) (microneutralization assay) is time consuming and requires an expert to perform manual evaluation. An automated neutralization assay could shorten the testing time, improve reproducibility, and provide automatic analysis. This study aimed to develop a high-throughput flow cytometric neutralization assay to screen for EVA71 neutralizing antibodies, and to develop quality control materials to ensure accurate testing. The results of this study demonstrate the high potential viability of the proposed flow cytometric method. Compared to the standard method, the flow cytometric method was shown to require a smaller sample volume, provide a much faster turnaround time, provide a rapid result for interpreting the neutralizing antibody level, and allow for possible quantification of results. The observed drawbacks of the proposed method include higher cost per test, longer hands-on time, and lower sensitivity in low titer conditions, which could lead to false negative results. The developed quality control materials were demonstrated to be effective and storable for 1 month. These results pave the way for the optimization and implementation of an automated neutralization assay to screen for neutralizing antibodies not only against EVA71, but also against other viruses in the enterovirus genus.
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Affiliation(s)
- Artit Wongsa
- Center of Research Excellence in Immunoregulation, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok, Thailand
| | - Thongkoon Priengprom
- Center of Research Excellence in Immunoregulation, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok, Thailand
| | - Jantip Saelee
- Center of Research Excellence in Immunoregulation, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok, Thailand
| | - Chintana Phawong
- Department of Medical Technology, Faculty of Medicine, Western University, Pathum Thani, Thailand
| | - Boonrat Tassaneetrithep
- Center of Research Excellence in Immunoregulation, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok, Thailand.
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2
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Beach SS, Hull MA, Ytreberg FM, Patel JS, Miura TA. Molecular Modeling Predicts Novel Antibody Escape Mutations in the Respiratory Syncytial Virus Fusion Glycoprotein. J Virol 2022; 96:e0035322. [PMID: 35678603 PMCID: PMC9278155 DOI: 10.1128/jvi.00353-22] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Monoclonal antibodies are increasingly used for the prevention and/or treatment of viral infections. One caveat of their use is the ability of viruses to evolve resistance to antibody binding and neutralization. Computational strategies to identify viral mutations that may disrupt antibody binding would leverage the wealth of viral genomic sequence data to monitor for potential antibody-resistant mutations. The respiratory syncytial virus is an important pathogen for which monoclonal antibodies against the fusion (F) protein are used to prevent severe disease in high-risk infants. In this study, we used an approach that combines molecular dynamics simulations with FoldX to estimate changes in free energy in F protein folding and binding to the motavizumab antibody upon each possible amino acid change. We systematically selected 8 predicted escape mutations and tested them in an infectious clone. Consistent with our F protein stability predictions, replication-effective viruses were observed for each selected mutation. Six of the eight variants showed increased resistance to neutralization by motavizumab. Flow cytometry was used to validate the estimated (model-predicted) effects on antibody binding to F. Using surface plasmon resonance, we determined that changes in the on-rate of motavizumab binding were associated with the reduced affinity for two novel escape mutations. Our study empirically validated the accuracy of our molecular modeling approach and emphasized the role of biophysical protein modeling in predicting viral resistance to antibody-based therapeutics that can be used to monitor the emergence of resistant viruses and to design improved therapeutic antibodies. IMPORTANCE Respiratory syncytial virus (RSV) causes severe disease in young infants, particularly those with heart or lung diseases or born prematurely. Because no vaccine is currently available, monoclonal antibodies are used to prevent severe RSV disease in high-risk infants. While it is known that RSV evolves to avoid recognition by antibodies, screening tools that can predict which changes to the virus may lead to antibody resistance are greatly needed.
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Affiliation(s)
- Sierra S. Beach
- Department of Biological Sciences, University of Idahogrid.266456.5, Moscow, Idaho, USA
| | - McKenna A. Hull
- Department of Biological Sciences, University of Idahogrid.266456.5, Moscow, Idaho, USA
| | - F. Marty Ytreberg
- Department of Physics, University of Idahogrid.266456.5, Moscow, Idaho, USA
- Institute for Modeling Collaboration and Innovation, University of Idahogrid.266456.5, Moscow, Idaho, USA
| | - Jagdish Suresh Patel
- Department of Biological Sciences, University of Idahogrid.266456.5, Moscow, Idaho, USA
- Institute for Modeling Collaboration and Innovation, University of Idahogrid.266456.5, Moscow, Idaho, USA
| | - Tanya A. Miura
- Department of Biological Sciences, University of Idahogrid.266456.5, Moscow, Idaho, USA
- Institute for Modeling Collaboration and Innovation, University of Idahogrid.266456.5, Moscow, Idaho, USA
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3
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Balinsky C, Jani V, Sun P, Williams M, Defang G, Porter KR. Pseudovirus-Based Assays for the Measurement of Antibody-Mediated Neutralization of SARS-CoV-2. Methods Mol Biol 2022; 2452:361-378. [PMID: 35554917 DOI: 10.1007/978-1-0716-2111-0_21] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
SARS-CoV-2 has emerged as a significant cause of morbidity and mortality worldwide. Virus neutralization assays are critical for the development and evaluation of vaccines and immunotherapeutics, as well as for conducting basic research into the immune response, spread, and pathogenesis of this disease. However, neutralization assays traditionally require the use of infectious virus which must be carefully handled in a BSL-3 setting, thus complicating the assay and restricting its use to labs with access to BSL-3 facilities. Pseudovirus-based assays are an alternative to the use of infectious virus. SARS-CoV-2 pseudovirus contains only the spike structural protein, and infection results in a single round of replication, thus allowing for the assay to be run safely under BSL-2 conditions. In this chapter, we describe protocols and considerations for the production and titration of lentivirus-based SARS-CoV-2 pseudovirus, as well as for running and analysis of FACS-based pseudovirus neutralization assays.
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Affiliation(s)
- Corey Balinsky
- Henry M. Jackson Foundation for the Advancement of Military Medicine, Bethesda, MD, USA
| | - Vihasi Jani
- Henry M. Jackson Foundation for the Advancement of Military Medicine, Bethesda, MD, USA
| | - Peifang Sun
- Viral and Rickettsial Diseases Department, Naval Medical Research Center, Silver Spring, MD, USA
| | - Maya Williams
- Chemistry Division, US Naval Research Laboratory, Washington, DC, USA
| | - Gabriel Defang
- Viral and Rickettsial Diseases Department, Naval Medical Research Center, Silver Spring, MD, USA
| | - Kevin R Porter
- Viral and Rickettsial Diseases Department, Naval Medical Research Center, Silver Spring, MD, USA
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4
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Boonyaratanakornkit J, Sholukh AM, Gray M, Bossard EL, Ford ES, Corbett KS, Corey L, Taylor JJ. Methods to Measure Antibody Neutralization of Live Human Coronavirus OC43. Viruses 2021; 13:2075. [PMID: 34696505 PMCID: PMC8540522 DOI: 10.3390/v13102075] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2021] [Revised: 10/08/2021] [Accepted: 10/10/2021] [Indexed: 01/13/2023] Open
Abstract
The human Betacoronavirus OC43 is a common cause of respiratory viral infections in adults and children. Lung infections with OC43 are associated with mortality, especially in hematopoietic stem cell transplant recipients. Neutralizing antibodies play a major role in protection against many respiratory viral infections, but to date a live viral neutralization assay for OC43 has not been described. We isolated a human monoclonal antibody (OC2) that binds to the spike protein of OC43 and neutralizes the live virus derived from the original isolate of OC43. We used this monoclonal antibody to develop and test the performance of two readily accessible in vitro assays for measuring antibody neutralization, one utilizing cytopathic effect and another utilizing an ELISA of infected cells. We used both methods to measure the neutralizing activity of the OC2 monoclonal antibody and of human plasma. These assays could prove useful for studying humoral responses to OC43 and cross-neutralization with other medically important betacoronaviruses.
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Affiliation(s)
- Jim Boonyaratanakornkit
- Vaccine and Infectious Disease Division, Fred Hutchinson Cancer Center, Seattle, WA 98109, USA
- Department of Medicine, University of Washington, Seattle, WA 98195, USA
| | - Anton M Sholukh
- Vaccine and Infectious Disease Division, Fred Hutchinson Cancer Center, Seattle, WA 98109, USA
| | - Matthew Gray
- Vaccine and Infectious Disease Division, Fred Hutchinson Cancer Center, Seattle, WA 98109, USA
| | - Emily L Bossard
- Vaccine and Infectious Disease Division, Fred Hutchinson Cancer Center, Seattle, WA 98109, USA
| | - Emily S Ford
- Vaccine and Infectious Disease Division, Fred Hutchinson Cancer Center, Seattle, WA 98109, USA
- Department of Medicine, University of Washington, Seattle, WA 98195, USA
| | - Kizzmekia S Corbett
- Vaccine Research Center, National Institutes of Health, Bethesda, MD 20892, USA
| | - Lawrence Corey
- Vaccine and Infectious Disease Division, Fred Hutchinson Cancer Center, Seattle, WA 98109, USA
- Department of Medicine, University of Washington, Seattle, WA 98195, USA
- Department of Laboratory Medicine and Pathology, University of Washington, Seattle, WA 98195, USA
| | - Justin J Taylor
- Vaccine and Infectious Disease Division, Fred Hutchinson Cancer Center, Seattle, WA 98109, USA
- Department of Immunology, University of Washington, Seattle, WA 98109, USA
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5
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Raghunandan R, Higgins D, Hosken N. RSV neutralization assays - Use in immune response assessment. Vaccine 2021; 39:4591-4597. [PMID: 34244007 DOI: 10.1016/j.vaccine.2021.06.016] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2021] [Revised: 06/03/2021] [Accepted: 06/04/2021] [Indexed: 01/26/2023]
Abstract
Respiratory syncytial virus (RSV) is a leading cause of respiratory illness among children and infants worldwide, yet no licensed vaccine exists to reduce the risk of disease. At least 16 RSV vaccine candidates are currently in clinical development and many are designed to induce robust virus neutralizing immune responses. RSV neutralizing antibody (nAb)-mediated interventions such as intravenous immunoglobulin (IVIG) and palivizumab provide passive protection against serious lower respiratory tract disease due to RSV, validating nAbs as a correlate of protection. To identify correlates of protection for vaccine candidates that have demonstrated their protective efficacy, an investigator can use assays designed to measure nAb responses. However, there is no standard method of measurement; individual laboratories have developed their own methods to measure the ability of nAbs to reduce the infectivity of a defined virus dose in a variety of cell lines, leading to establishment of the broad variety of RSV neutralization assay formats currently in use. Standardizing the RSV neutralization assay is an essential step toward better assessment of nAb responses to vaccine candidates. Use of a common reference standard by all makes comparing the immunogenicity of different vaccine candidates feasible. In the context of vaccine development, the WHO 1st International Standard for Antiserum to RSV (RSV IS) has been shown to be suitable for harmonizing results across laboratories and assay formats used to measure nAb titers to RSV/A and RSV/B in human sera. This review describes the broad variety of RSV virus neutralization assay formats currently in use and the importance of the RSV IS for harmonization of results across formats and across laboratories. It also outlines good practices for key assay components and data analysis to promote the quality and consistency of measuring RSV nAb titers in serum specimens.
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6
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Development and qualification of a fast, high-throughput and robust imaging-based neutralization assay for respiratory syncytial virus. J Immunol Methods 2021; 494:113054. [PMID: 33845088 DOI: 10.1016/j.jim.2021.113054] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2021] [Revised: 03/30/2021] [Accepted: 04/05/2021] [Indexed: 01/22/2023]
Abstract
Respiratory syncytial virus (RSV) is a common pathogen causing severe respiratory illness in infants and elder adults. The development of an effective RSV vaccine is an important unmet medical need and an area of active research. The traditional method for testing neutralizing antibodies against RSV in clinical trials is the plaque reduction neutralization test (PRNT), which uses 24-well plates and needs several days post infection to develop viral plaques. In this study, we have developed a virus reduction neutralization test (VRNT), which allows the number of RSV infected cells to be automatically counted by an imaging cytometer at one day post infection in 96-well plates. VRNT was found robust to cell seeding density, detection antibody concentration, virus input and infection time. By testing twenty human sera, we have shown good correlation between VRNT50 and PRNT50 titers for multiple RSV strains: A2, Long and 18537 (serotype B). To understand the VRNT performance, eight human serum samples with high, medium and low neutralization titers were selected for VRNT qualification. We have demonstrated that VRNT had good specificity, precision, linearity and relative accuracy. In conclusion, VRNT is a better alternative to PRNT in serum neutralization test for RSV vaccine candidates.
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Creanga A, Gillespie RA, Fisher BE, Andrews SF, Lederhofer J, Yap C, Hatch L, Stephens T, Tsybovsky Y, Crank MC, Ledgerwood JE, McDermott AB, Mascola JR, Graham BS, Kanekiyo M. A comprehensive influenza reporter virus panel for high-throughput deep profiling of neutralizing antibodies. Nat Commun 2021; 12:1722. [PMID: 33741916 PMCID: PMC7979723 DOI: 10.1038/s41467-021-21954-2] [Citation(s) in RCA: 29] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2020] [Accepted: 02/22/2021] [Indexed: 01/31/2023] Open
Abstract
Broadly neutralizing antibodies (bnAbs) have been developed as potential countermeasures for seasonal and pandemic influenza. Deep characterization of these bnAbs and polyclonal sera provides pivotal understanding for influenza immunity and informs effective vaccine design. However, conventional virus neutralization assays require high-containment laboratories and are difficult to standardize and roboticize. Here, we build a panel of engineered influenza viruses carrying a reporter gene to replace an essential viral gene, and develop an assay using the panel for in-depth profiling of neutralizing antibodies. Replication of these viruses is restricted to cells expressing the missing viral gene, allowing it to be manipulated in a biosafety level 2 environment. We generate the neutralization profile of 24 bnAbs using a 55-virus panel encompassing the near-complete diversity of human H1N1 and H3N2, as well as pandemic subtype viruses. Our system offers in-depth profiling of influenza immunity, including the antibodies against the hemagglutinin stem, a major target of universal influenza vaccines.
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Affiliation(s)
- Adrian Creanga
- Vaccine Research Center, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, USA
| | - Rebecca A Gillespie
- Vaccine Research Center, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, USA
| | - Brian E Fisher
- Vaccine Research Center, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, USA
| | - Sarah F Andrews
- Vaccine Research Center, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, USA
| | - Julia Lederhofer
- Vaccine Research Center, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, USA
| | - Christina Yap
- Vaccine Research Center, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, USA
| | - Liam Hatch
- Vaccine Research Center, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, USA
| | - Tyler Stephens
- Electron Microscopy Laboratory, Cancer Research Technology Program, Frederick National Laboratory for Cancer Research sponsored by the National Cancer Institute, Frederick, MD, USA
| | - Yaroslav Tsybovsky
- Electron Microscopy Laboratory, Cancer Research Technology Program, Frederick National Laboratory for Cancer Research sponsored by the National Cancer Institute, Frederick, MD, USA
| | - Michelle C Crank
- Vaccine Research Center, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, USA
| | - Julie E Ledgerwood
- Vaccine Research Center, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, USA
| | - Adrian B McDermott
- Vaccine Research Center, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, USA
| | - John R Mascola
- Vaccine Research Center, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, USA
| | - Barney S Graham
- Vaccine Research Center, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, USA.
| | - Masaru Kanekiyo
- Vaccine Research Center, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, USA.
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8
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Neutralization mechanism of human monoclonal antibodies against Rift Valley fever virus. Nat Microbiol 2019; 4:1231-1241. [DOI: 10.1038/s41564-019-0411-z] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2018] [Accepted: 02/14/2019] [Indexed: 02/03/2023]
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9
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Sun YP, Zhang W, Zhao QJ, Cao JL, Zhang LJ, Xiang JY, Si JY, Lin X, Chen L, Zheng ZZ, Xia NS. An optimized high-throughput fluorescence plate reader-based RSV neutralization assay. J Virol Methods 2018; 260:34-40. [PMID: 30003925 DOI: 10.1016/j.jviromet.2018.07.004] [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: 12/05/2017] [Revised: 07/04/2018] [Accepted: 07/08/2018] [Indexed: 02/03/2023]
Abstract
A licensed vaccine for respiratory syncytial virus (RSV) has yet to be developed, and a reliable and repeatable neutralizing assay is indispensable for vaccine development. Here, we demonstrated an optimized high-throughput RSV neutralization assay that utilizes a fluorescence plate reader (reader) as a substitute for flow cytometry to detect fluorescent signals in RSV-A2 mKate-infected cells. Furthermore, this study tested the influence of virus input and infectivity on the neutralizing assay and highlighted critical factors (together with a suggested protocol) for obtaining stable data using this assay.
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Affiliation(s)
- Yong-Peng Sun
- State Key Laboratory of Molecular Vaccinology and Molecular Diagnostics, National Institute of Diagnostics and Vaccine Development in Infectious Diseases, School of Public Health, Xiamen University, Xiamen, Fujian 361002, PR China.
| | - Wei Zhang
- State Key Laboratory of Molecular Vaccinology and Molecular Diagnostics, National Institute of Diagnostics and Vaccine Development in Infectious Diseases, School of Public Health School of Life Sciences, Xiamen University, Xiamen, Fujian 361002, PR China.
| | - Qin-Jian Zhao
- State Key Laboratory of Molecular Vaccinology and Molecular Diagnostics, National Institute of Diagnostics and Vaccine Development in Infectious Diseases, School of Public Health, Xiamen University, Xiamen, Fujian 361002, PR China.
| | - Jian-Li Cao
- State Key Laboratory of Molecular Vaccinology and Molecular Diagnostics, National Institute of Diagnostics and Vaccine Development in Infectious Diseases, School of Public Health School of Life Sciences, Xiamen University, Xiamen, Fujian 361002, PR China.
| | - Lu-Jing Zhang
- State Key Laboratory of Molecular Vaccinology and Molecular Diagnostics, National Institute of Diagnostics and Vaccine Development in Infectious Diseases, School of Public Health, Xiamen University, Xiamen, Fujian 361002, PR China.
| | - Jiang-Yan Xiang
- State Key Laboratory of Molecular Vaccinology and Molecular Diagnostics, National Institute of Diagnostics and Vaccine Development in Infectious Diseases, School of Public Health School of Life Sciences, Xiamen University, Xiamen, Fujian 361002, PR China.
| | - Jun-Yu Si
- State Key Laboratory of Molecular Vaccinology and Molecular Diagnostics, National Institute of Diagnostics and Vaccine Development in Infectious Diseases, School of Public Health School of Life Sciences, Xiamen University, Xiamen, Fujian 361002, PR China.
| | - Xue Lin
- State Key Laboratory of Molecular Vaccinology and Molecular Diagnostics, National Institute of Diagnostics and Vaccine Development in Infectious Diseases, School of Public Health, Xiamen University, Xiamen, Fujian 361002, PR China.
| | - Li Chen
- State Key Laboratory of Molecular Vaccinology and Molecular Diagnostics, National Institute of Diagnostics and Vaccine Development in Infectious Diseases, School of Public Health, Xiamen University, Xiamen, Fujian 361002, PR China.
| | - Zi-Zheng Zheng
- State Key Laboratory of Molecular Vaccinology and Molecular Diagnostics, National Institute of Diagnostics and Vaccine Development in Infectious Diseases, School of Public Health, Xiamen University, Xiamen, Fujian 361002, PR China.
| | - Ning-Shao Xia
- State Key Laboratory of Molecular Vaccinology and Molecular Diagnostics, National Institute of Diagnostics and Vaccine Development in Infectious Diseases, School of Public Health, Xiamen University, Xiamen, Fujian 361002, PR China; State Key Laboratory of Molecular Vaccinology and Molecular Diagnostics, National Institute of Diagnostics and Vaccine Development in Infectious Diseases, School of Public Health School of Life Sciences, Xiamen University, Xiamen, Fujian 361002, PR China.
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10
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Boukhvalova MS, Mbaye A, Kovtun S, Yim KC, Konstantinova T, Getachew T, Khurana S, Falsey AR, Blanco JCG. Improving ability of RSV microneutralization assay to detect G-specific and cross-reactive neutralizing antibodies through immortalized cell line selection. Vaccine 2018; 36:4657-4662. [PMID: 29960801 DOI: 10.1016/j.vaccine.2018.06.045] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2018] [Revised: 06/08/2018] [Accepted: 06/16/2018] [Indexed: 11/29/2022]
Abstract
Respiratory syncytial virus (RSV) is a significant cause of bronchiolitis and pneumonia. Protection against RSV is associated with neutralizing antibodies against the fusion (F) and attachment (G) glycoproteins. Several RSV vaccine candidates are in development, but their immunogenicity is hard to compare due to the little-understood differences between multiple RSV neutralizing antibody assays used. Existing assays utilize primarily Vero or HEp-2 cells, but their ability to detect G-neutralizing antibodies or antibodies against specific RSV strains is unclear. In this work, we developed an RSV microneutralization assay (MNA) using unmodified RSV and immortalized cell line derived from human airway epithelial cells (A549). Performance of A549-, HEp-2- and Vero-based MNA was compared under the same assay conditions (fixed amount of virus and cells) with regards to detection of neutralizing antibodies against RSV A or B viruses, G-reactive neutralizing antibodies, and effect of complement. Our results indicate that A549 cells yield the highest MNA titers, particularly in the RSV A/A2 MNA, are least susceptible to complement-enhancing effect of neutralizing titer readout and are superior to Vero or HEp-2 MNA at recognizing G-reactive neutralizing antibodies when no complement is used. Vero cells, however, can be more consistent at recognizing neutralizing antibodies against multiple RSV strains. The choice of substrate cells thus affects the outcome of MNA, as some immortalized cells better support detection of broader range of neutralizing antibodies, while others facilitate detection of G-targeting neutralizing antibodies, a long-thought prerogative of primary airway epithelial cells.
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Affiliation(s)
- M S Boukhvalova
- Sigmovir Biosystems, Inc, 9610 Medical Center Drive, Suite 100, Rockville, MD 20850, USA.
| | - A Mbaye
- Sigmovir Biosystems, Inc, 9610 Medical Center Drive, Suite 100, Rockville, MD 20850, USA
| | - S Kovtun
- Sigmovir Biosystems, Inc, 9610 Medical Center Drive, Suite 100, Rockville, MD 20850, USA
| | - K C Yim
- Sigmovir Biosystems, Inc, 9610 Medical Center Drive, Suite 100, Rockville, MD 20850, USA
| | - T Konstantinova
- Sigmovir Biosystems, Inc, 9610 Medical Center Drive, Suite 100, Rockville, MD 20850, USA
| | - T Getachew
- Sigmovir Biosystems, Inc, 9610 Medical Center Drive, Suite 100, Rockville, MD 20850, USA
| | - S Khurana
- Division of Viral Products, Center for Biologics Evaluation and Research (CBER), Food and Drug Administration (FDA), 10903 New Hampshire Avenue, Silver Spring, MD 20993, USA
| | - A R Falsey
- University of Rochester Medical Center, Rochester General Hospital, 1425 Portland Avenue, Infectious Diseases Unit, Rochester, NY 14621, USA
| | - J C G Blanco
- Sigmovir Biosystems, Inc, 9610 Medical Center Drive, Suite 100, Rockville, MD 20850, USA
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11
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Goodwin E, Gilman MSA, Wrapp D, Chen M, Ngwuta JO, Moin SM, Bai P, Sivasubramanian A, Connor RI, Wright PF, Graham BS, McLellan JS, Walker LM. Infants Infected with Respiratory Syncytial Virus Generate Potent Neutralizing Antibodies that Lack Somatic Hypermutation. Immunity 2018; 48:339-349.e5. [PMID: 29396163 PMCID: PMC6005179 DOI: 10.1016/j.immuni.2018.01.005] [Citation(s) in RCA: 106] [Impact Index Per Article: 17.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2017] [Revised: 11/03/2017] [Accepted: 12/29/2017] [Indexed: 11/17/2022]
Abstract
Respiratory syncytial virus (RSV) is a leading cause of infant mortality, and there are currently no licensed vaccines to protect this vulnerable population. A comprehensive understanding of infant antibody responses to natural RSV infection would facilitate vaccine development. Here, we isolated more than 450 RSV fusion glycoprotein (F)-specific antibodies from 7 RSV-infected infants and found that half of the antibodies recognized only two antigenic sites. Antibodies targeting both sites showed convergent sequence features, and structural studies revealed the molecular basis for their recognition of RSV F. A subset of antibodies targeting one of these sites displayed potent neutralizing activity despite lacking somatic mutations, and similar antibodies were detected in RSV-naive B cell repertoires, suggesting that expansion of these B cells in infants may be possible with suitably designed vaccine antigens. Collectively, our results provide fundamental insights into infant antibody responses and a framework for the rational design of age-specific RSV vaccines.
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Affiliation(s)
| | - Morgan S A Gilman
- Department of Biochemistry and Cell Biology, Geisel School of Medicine at Dartmouth, Hanover, NH 03755, USA
| | - Daniel Wrapp
- Department of Biochemistry and Cell Biology, Geisel School of Medicine at Dartmouth, Hanover, NH 03755, USA
| | - Man Chen
- Vaccine Research Center, National Institute of Allergy and Infectious Diseases, NIH, Bethesda, MD 20892, USA
| | - Joan O Ngwuta
- Vaccine Research Center, National Institute of Allergy and Infectious Diseases, NIH, Bethesda, MD 20892, USA
| | - Syed M Moin
- Vaccine Research Center, National Institute of Allergy and Infectious Diseases, NIH, Bethesda, MD 20892, USA
| | - Patricia Bai
- Department of Microbiology and Immunology, Geisel School of Medicine at Dartmouth, Hanover, NH 03755, USA
| | | | - Ruth I Connor
- Department of Microbiology and Immunology, Geisel School of Medicine at Dartmouth, Hanover, NH 03755, USA
| | - Peter F Wright
- Department of Pediatrics, Geisel School of Medicine at Dartmouth, Hanover, NH 03755, USA
| | - Barney S Graham
- Vaccine Research Center, National Institute of Allergy and Infectious Diseases, NIH, Bethesda, MD 20892, USA
| | - Jason S McLellan
- Department of Biochemistry and Cell Biology, Geisel School of Medicine at Dartmouth, Hanover, NH 03755, USA.
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12
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Development of a High-Throughput Respiratory Syncytial Virus Fluorescent Focus-Based Microneutralization Assay. CLINICAL AND VACCINE IMMUNOLOGY : CVI 2017; 24:CVI.00225-17. [PMID: 29021302 PMCID: PMC5717189 DOI: 10.1128/cvi.00225-17] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/03/2017] [Accepted: 09/30/2017] [Indexed: 11/21/2022]
Abstract
Neutralizing antibodies specific for respiratory syncytial virus (RSV) represent a major protective mechanism against RSV infection, as demonstrated by the efficacy of the immune-prophylactic monoclonal antibody palivizumab in preventing RSV-associated lower respiratory tract infections in premature infants. Accordingly, the RSV neutralization assay has become a key functional method to assess the neutralizing activity of serum antibodies in preclinical animal models, epidemiology studies, and clinical trials. In this study, we qualified a 24-h, fluorescent focus-based microneutralization (RSVA FFA-MN) method that requires no medium exchange or pre- or postinfection processing to detect green fluorescent protein-expressing RSV strain A2 (RSVA-GFP)-infected cells, using a high-content imaging system for automated image acquisition and focus enumeration. The RSVA FFA-MN method was shown to be sensitive, with a limit of detection (LOD) and limit of quantitation (LOQ) of 1:10, or 3.32 log2; linear over a range of 4.27 to 9.65 log2 50% inhibitory concentration (IC50); and precise, with intra- and interassay coefficients of variation of <21%. This precision allowed the choice of a statistically justified 3-fold-rise seroresponse cutoff criterion. The repeatability and robustness of this method were demonstrated by including a pooled human serum sample in every assay as a positive control (PC). Over 3 years of testing between two laboratories, this PC generated data falling within 2.5 standard deviations of the mean 98.7% of the time (n = 1,720). This high-throughput and reliable RSV microneutralization assay has proven useful for testing sera from preclinical vaccine candidate evaluation studies, epidemiology studies, and both pediatric and adult vaccine clinical trials.
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13
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RSV glycoprotein and genomic RNA dynamics reveal filament assembly prior to the plasma membrane. Nat Commun 2017; 8:667. [PMID: 28939853 PMCID: PMC5610308 DOI: 10.1038/s41467-017-00732-z] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2016] [Accepted: 07/20/2017] [Indexed: 11/25/2022] Open
Abstract
The human respiratory syncytial virus G protein plays an important role in the entry and assembly of filamentous virions. Here, we report the use of fluorescently labeled soybean agglutinin to selectively label the respiratory syncytial virus G protein in living cells without disrupting respiratory syncytial virus infectivity or filament formation and allowing for interrogations of respiratory syncytial virus virion assembly. Using this approach, we discovered that plasma membrane-bound respiratory syncytial virus G rapidly recycles from the membrane via clathrin-mediated endocytosis. This event is then followed by the dynamic formation of filamentous and branched respiratory syncytial virus particles, and assembly with genomic ribonucleoproteins and caveolae-associated vesicles prior to re-insertion into the plasma membrane. We demonstrate that these processes are halted by the disruption of microtubules and inhibition of molecular motors. Collectively, our results show that for respiratory syncytial virus assembly, viral filaments are produced and loaded with genomic RNA prior to insertion into the plasma membrane. Assembly of filamentous RSV particles is incompletely understood due to a lack of techniques suitable for live-cell imaging. Here Vanover et al. use labeled soybean agglutinin to selectively label RSV G protein and show how filamentous RSV assembly, initiated in the cytoplasm, uses G protein recycled from the plasma membrane.
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14
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Zhao M, Zheng ZZ, Chen M, Modjarrad K, Zhang W, Zhan LT, Cao JL, Sun YP, McLellan JS, Graham BS, Xia NS. Discovery of a Prefusion Respiratory Syncytial Virus F-Specific Monoclonal Antibody That Provides Greater In Vivo Protection than the Murine Precursor of Palivizumab. J Virol 2017; 91:e00176-17. [PMID: 28539438 PMCID: PMC5651723 DOI: 10.1128/jvi.00176-17] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2017] [Accepted: 05/09/2017] [Indexed: 11/20/2022] Open
Abstract
Palivizumab, a humanized murine monoclonal antibody that recognizes antigenic site II on both the prefusion (pre-F) and postfusion (post-F) conformations of the respiratory syncytial virus (RSV) F glycoprotein, is the only prophylactic agent approved for use for the treatment of RSV infection. However, its relatively low neutralizing potency and high cost have limited its use to a restricted population of infants at high risk of severe disease. Previously, we isolated a high-potency neutralizing antibody, 5C4, that specifically recognizes antigenic site Ø at the apex of the pre-F protein trimer. We compared in vitro and in vivo the potency and protective efficacy of 5C4 and the murine precursor of palivizumab, antibody 1129. Both antibodies were synthesized on identical murine backbones as either an IgG1 or IgG2a subclass and evaluated for binding to multiple F protein conformations, in vitro inhibition of RSV infection and propagation, and protective efficacy in mice. Although 1129 and 5C4 had similar pre-F protein binding affinities, the 5C4 neutralizing activity was nearly 50-fold greater than that of 1129 in vitro In BALB/c mice, 5C4 reduced the peak titers of RSV 1,000-fold more than 1129 did in both the upper and lower respiratory tracts. These data indicate that antibodies specific for antigenic site Ø are more efficacious at preventing RSV infection than antibodies specific for antigenic site II. Our data also suggest that site Ø-specific antibodies may be useful for the prevention or treatment of RSV infection and support the use of the pre-F protein as a vaccine antigen.IMPORTANCE There is no vaccine yet available to prevent RSV infection. The use of the licensed antibody palivizumab, which recognizes site II on both the pre-F and post-F proteins, is restricted to prophylaxis in neonates at high risk of severe RSV disease. Recommendations for using passive immunization in the general population or for therapy in immunocompromised persons with persistent infection is limited because of cost, determined from the high doses needed to compensate for its relatively low neutralizing potency. Prior efforts to improve the in vitro potency of site II-specific antibodies did not translate to significant in vivo dose sparing. We isolated a pre-F protein-specific, high-potency neutralizing antibody (5C4) that recognizes antigenic site Ø and compared its efficacy to that of the murine precursor of palivizumab (antibody 1129) matched for isotype and pre-F protein binding affinities. Our findings demonstrate that epitope specificity is an important determinant of antibody neutralizing potency, and defining the mechanisms of neutralization has the potential to identify improved products for the prevention and treatment of RSV infection.
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Affiliation(s)
- Min Zhao
- State Key Laboratory of Molecular Vaccinology and Molecular Diagnostics, School of Public Health, Xiamen University, Xiamen, Fujian, People's Republic of China
- National Institute of Diagnostics and Vaccine Development in Infectious Diseases, School of Life Sciences, Xiamen University, Xiamen, Fujian, People's Republic of China
- Vaccine Research Center, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland, USA
| | - Zi-Zheng Zheng
- State Key Laboratory of Molecular Vaccinology and Molecular Diagnostics, School of Public Health, Xiamen University, Xiamen, Fujian, People's Republic of China
| | - Man Chen
- Vaccine Research Center, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland, USA
| | - Kayvon Modjarrad
- Military HIV Research Program, Walter Reed Army Institute of Research, Silver Spring, Maryland, USA
| | - Wei Zhang
- National Institute of Diagnostics and Vaccine Development in Infectious Diseases, School of Life Sciences, Xiamen University, Xiamen, Fujian, People's Republic of China
| | - Lu-Ting Zhan
- State Key Laboratory of Molecular Vaccinology and Molecular Diagnostics, School of Public Health, Xiamen University, Xiamen, Fujian, People's Republic of China
| | - Jian-Li Cao
- National Institute of Diagnostics and Vaccine Development in Infectious Diseases, School of Life Sciences, Xiamen University, Xiamen, Fujian, People's Republic of China
| | - Yong-Peng Sun
- State Key Laboratory of Molecular Vaccinology and Molecular Diagnostics, School of Public Health, Xiamen University, Xiamen, Fujian, People's Republic of China
| | - Jason S McLellan
- Department of Biochemistry and Cell Biology, Geisel School of Medicine at Dartmouth, Hanover, New Hampshire, USA
| | - Barney S Graham
- Vaccine Research Center, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland, USA
| | - Ning-Shao Xia
- State Key Laboratory of Molecular Vaccinology and Molecular Diagnostics, School of Public Health, Xiamen University, Xiamen, Fujian, People's Republic of China
- National Institute of Diagnostics and Vaccine Development in Infectious Diseases, School of Life Sciences, Xiamen University, Xiamen, Fujian, People's Republic of China
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15
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A rapid, simple, and accurate plaque assay for human respiratory syncytial virus (HRSV). J Immunol Methods 2017; 446:15-20. [DOI: 10.1016/j.jim.2017.03.020] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2016] [Revised: 02/13/2017] [Accepted: 03/30/2017] [Indexed: 11/21/2022]
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16
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Killikelly AM, Kanekiyo M, Graham BS. Pre-fusion F is absent on the surface of formalin-inactivated respiratory syncytial virus. Sci Rep 2016; 6:34108. [PMID: 27682426 PMCID: PMC5040956 DOI: 10.1038/srep34108] [Citation(s) in RCA: 87] [Impact Index Per Article: 10.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2016] [Accepted: 09/05/2016] [Indexed: 12/15/2022] Open
Abstract
The lack of a licensed vaccine for respiratory syncytial virus (RSV) can be partly attributed to regulatory hurdles resulting from vaccine enhanced respiratory disease (ERD) subsequent to natural RSV infection that was observed in clinical trials of formalin-inactivated RSV (FI-RSV) in antigen-naïve infants. To develop an effective vaccine that does not enhance RSV illness, it is important to understand how formalin and heat inactivation affected the antigenicity and immunogenicity of FI-RSV compared to native virus. Informed by atomic structures of RSV fusion (F) glycoprotein in prefusion (pre-F) and postfusion (post-F) conformations, we demonstrate that FI-RSV predominately presents post-F on the virion surface, whereas infectious RSV presents both pre-F and post-F conformations. This significant antigenic distinction has not been previously appreciated. Thus, a stabilized pre-F antigen is more representative of live RSV than F in its post-F conformation, as displayed on the surface of FI-RSV. This finding has major implications for discriminating current pre-F-based immunogens from FI-RSV used in historical vaccine trials.
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Affiliation(s)
- April M Killikelly
- Vaccine Research Center, National Institute of Infectious Diseases, National Institutes of Health, Bethesda, MD 20892, United States
| | - Masaru Kanekiyo
- Vaccine Research Center, National Institute of Infectious Diseases, National Institutes of Health, Bethesda, MD 20892, United States
| | - Barney S Graham
- Vaccine Research Center, National Institute of Infectious Diseases, National Institutes of Health, Bethesda, MD 20892, United States
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17
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Cai W, Tang ZM, Wen GP, Wang SL, Ji WF, Yang M, Ying D, Zheng ZZ, Xia NS. A high-throughput neutralizing assay for antibodies and sera against hepatitis E virus. Sci Rep 2016; 6:25141. [PMID: 27122081 PMCID: PMC4848499 DOI: 10.1038/srep25141] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2015] [Accepted: 04/11/2016] [Indexed: 12/12/2022] Open
Abstract
Hepatitis E virus (HEV) is the aetiological agent of enterically transmitted hepatitis. The traditional methods for evaluating neutralizing antibody titres against HEV are real-time PCR and the immunofluorescence foci assay (IFA), which are poorly repeatable and operationally complicated, factors that limit their applicability to high-throughput assays. In this study, we developed a novel high-throughput neutralizing assay based on biotin-conjugated p239 (HEV recombinant capsid proteins, a.a. 368–606) and staining with allophycocyanin-conjugated streptavidin (streptavidin APC) to amplify the fluorescence signal. A linear regression analysis indicated that there was a high degree of correlation between IFA and the novel assay. Using this method, we quantitatively evaluated the neutralization of sera from HEV-infected and vaccinated macaques. The anti-HEV IgG level had good concordance with the neutralizing titres of macaque sera. However, the neutralization titres of the sera were also influenced by anti-HEV IgM responses. Further analysis also indicated that, although vaccination with HEV vaccine stimulated higher anti-HEV IgG and neutralization titres than infection with HEV in macaques, the proportions of neutralizing antibodies in the infected macaques’ sera were higher than in the vaccinated macaques with the same anti-HEV IgG levels. Thus, the infection more efficiently stimulated neutralizing antibody responses.
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Affiliation(s)
- Wei Cai
- State Key Laboratory of Molecular Vaccinology and Molecular Diagnostics, National Institute of Diagnostics and Vaccine Development in Infectious Diseases, School of Life Sciences, Xiamen University, Xiamen, Fujian 361005, PR China
| | - Zi-Min Tang
- State Key Laboratory of Molecular Vaccinology and Molecular Diagnostics, National Institute of Diagnostics and Vaccine Development in Infectious Diseases, School of Public Health, Xiamen University, Xiamen, Fujian 361005, PR China
| | - Gui-Ping Wen
- State Key Laboratory of Molecular Vaccinology and Molecular Diagnostics, National Institute of Diagnostics and Vaccine Development in Infectious Diseases, School of Public Health, Xiamen University, Xiamen, Fujian 361005, PR China
| | - Si-Ling Wang
- State Key Laboratory of Molecular Vaccinology and Molecular Diagnostics, National Institute of Diagnostics and Vaccine Development in Infectious Diseases, School of Public Health, Xiamen University, Xiamen, Fujian 361005, PR China
| | - Wen-Fang Ji
- State Key Laboratory of Molecular Vaccinology and Molecular Diagnostics, National Institute of Diagnostics and Vaccine Development in Infectious Diseases, School of Life Sciences, Xiamen University, Xiamen, Fujian 361005, PR China
| | - Min Yang
- State Key Laboratory of Molecular Vaccinology and Molecular Diagnostics, National Institute of Diagnostics and Vaccine Development in Infectious Diseases, School of Life Sciences, Xiamen University, Xiamen, Fujian 361005, PR China
| | - Dong Ying
- State Key Laboratory of Molecular Vaccinology and Molecular Diagnostics, National Institute of Diagnostics and Vaccine Development in Infectious Diseases, School of Life Sciences, Xiamen University, Xiamen, Fujian 361005, PR China
| | - Zi-Zheng Zheng
- State Key Laboratory of Molecular Vaccinology and Molecular Diagnostics, National Institute of Diagnostics and Vaccine Development in Infectious Diseases, School of Public Health, Xiamen University, Xiamen, Fujian 361005, PR China
| | - Ning-Shao Xia
- State Key Laboratory of Molecular Vaccinology and Molecular Diagnostics, National Institute of Diagnostics and Vaccine Development in Infectious Diseases, School of Life Sciences, Xiamen University, Xiamen, Fujian 361005, PR China.,State Key Laboratory of Molecular Vaccinology and Molecular Diagnostics, National Institute of Diagnostics and Vaccine Development in Infectious Diseases, School of Public Health, Xiamen University, Xiamen, Fujian 361005, PR China
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18
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Taylor G, Thom M, Capone S, Pierantoni A, Guzman E, Herbert R, Scarselli E, Napolitano F, Giuliani A, Folgori A, Colloca S, Cortese R, Nicosia A, Vitelli A. Efficacy of a virus-vectored vaccine against human and bovine respiratory syncytial virus infections. Sci Transl Med 2015; 7:300ra127. [DOI: 10.1126/scitranslmed.aac5757] [Citation(s) in RCA: 54] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
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19
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Gilman MSA, Moin SM, Mas V, Chen M, Patel NK, Kramer K, Zhu Q, Kabeche SC, Kumar A, Palomo C, Beaumont T, Baxa U, Ulbrandt ND, Melero JA, Graham BS, McLellan JS. Characterization of a Prefusion-Specific Antibody That Recognizes a Quaternary, Cleavage-Dependent Epitope on the RSV Fusion Glycoprotein. PLoS Pathog 2015; 11:e1005035. [PMID: 26161532 PMCID: PMC4498696 DOI: 10.1371/journal.ppat.1005035] [Citation(s) in RCA: 102] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2015] [Accepted: 06/19/2015] [Indexed: 12/13/2022] Open
Abstract
Prevention efforts for respiratory syncytial virus (RSV) have been advanced due to the recent isolation and characterization of antibodies that specifically recognize the prefusion conformation of the RSV fusion (F) glycoprotein. These potently neutralizing antibodies are in clinical development for passive prophylaxis and have also aided the design of vaccine antigens that display prefusion-specific epitopes. To date, prefusion-specific antibodies have been shown to target two antigenic sites on RSV F, but both of these sites are also present on monomeric forms of F. Here we present a structural and functional characterization of human antibody AM14, which potently neutralized laboratory strains and clinical isolates of RSV from both A and B subtypes. The crystal structure and location of escape mutations revealed that AM14 recognizes a quaternary epitope that spans two protomers and includes a region that undergoes extensive conformational changes in the pre- to postfusion F transition. Binding assays demonstrated that AM14 is unique in its specific recognition of trimeric furin-cleaved prefusion F, which is the mature form of F on infectious virions. These results demonstrate that the prefusion F trimer contains potent neutralizing epitopes not present on monomers and that AM14 should be particularly useful for characterizing the conformational state of RSV F-based vaccine antigens. Respiratory syncytial virus (RSV) causes significant morbidity and mortality in children, yet an efficacious vaccine remains unavailable. Antibodies that preferentially recognize the prefusion conformation of the fusion (F) glycoprotein, particularly those that bind antigenic site Ø at the membrane-distal apex, potently neutralize infection and have aided vaccine design. Here we characterize AM14, a potent human antibody, which we show recognizes a novel epitope midway between the membrane-proximal region and the apex of the prefusion F trimer. The epitope is evenly distributed across two protomers, causing AM14 to be uniquely trimer-specific and, surprisingly, cleavage-dependent. These results indicate that the prefusion trimer is antigenically distinct from the monomer. Our findings also demonstrate that epitopes other than site Ø can be the target of extremely potent neutralizing antibodies and thus provide a new target for structure-based vaccine design. Recognition of this novel epitope could make AM14 an ideal candidate for strategies that combine passive prophylaxis with vaccination, since binding of AM14 would not block elicitation of antibodies against site Ø. Due to its unique specificity, AM14 will also be valuable for probing the conformation of RSV F-based vaccine antigens designed to be in the furin-cleaved trimeric prefusion conformation.
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MESH Headings
- Antibodies, Neutralizing/chemistry
- Antibodies, Neutralizing/immunology
- Antibodies, Neutralizing/ultrastructure
- Antibodies, Viral/chemistry
- Antibodies, Viral/immunology
- Antibodies, Viral/ultrastructure
- Antigens, Viral/immunology
- Cell Line
- Chromatography, Gel
- Crystallography, X-Ray
- Enzyme-Linked Immunosorbent Assay
- Epitope Mapping
- Epitopes, B-Lymphocyte/chemistry
- Epitopes, B-Lymphocyte/immunology
- Epitopes, B-Lymphocyte/ultrastructure
- Flow Cytometry
- Glycoproteins/chemistry
- Glycoproteins/immunology
- Glycoproteins/ultrastructure
- Humans
- Protein Structure, Quaternary
- Respiratory Syncytial Viruses/immunology
- Surface Plasmon Resonance
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Affiliation(s)
- Morgan S. A. Gilman
- Department of Biochemistry, Geisel School of Medicine at Dartmouth, Hanover, New Hampshire, United States of America
| | - Syed M. Moin
- Vaccine Research Center, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland, United States of America
| | - Vicente Mas
- Centro Nacional de Microbiología and CIBER de Enfermedades Respiratorias, Instituto de Salud Carlos III, Majadahonda, Madrid, Spain
| | - Man Chen
- Vaccine Research Center, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland, United States of America
| | - Nita K. Patel
- MedImmune Inc., Gaithersburg, Maryland, United States of America
| | - Kari Kramer
- MedImmune Inc., Gaithersburg, Maryland, United States of America
| | - Qing Zhu
- MedImmune Inc., Gaithersburg, Maryland, United States of America
| | - Stephanie C. Kabeche
- Department of Biochemistry, Geisel School of Medicine at Dartmouth, Hanover, New Hampshire, United States of America
| | - Azad Kumar
- Vaccine Research Center, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland, United States of America
| | - Concepción Palomo
- Centro Nacional de Microbiología and CIBER de Enfermedades Respiratorias, Instituto de Salud Carlos III, Majadahonda, Madrid, Spain
| | - Tim Beaumont
- AIMM Therapeutics, Academic Medical Center, Amsterdam, Netherlands
| | - Ulrich Baxa
- Electron Microscopy Laboratory, Cancer Research Technology Program, Leidos Biomedical Research, Inc., Frederick National Laboratory for Cancer Research, Frederick, Maryland, United States of America
| | | | - José A. Melero
- Centro Nacional de Microbiología and CIBER de Enfermedades Respiratorias, Instituto de Salud Carlos III, Majadahonda, Madrid, Spain
| | - Barney S. Graham
- Vaccine Research Center, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland, United States of America
| | - Jason S. McLellan
- Department of Biochemistry, Geisel School of Medicine at Dartmouth, Hanover, New Hampshire, United States of America
- * E-mail:
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20
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Pierantoni A, Esposito ML, Ammendola V, Napolitano F, Grazioli F, Abbate A, del Sorbo M, Siani L, D’Alise AM, Taglioni A, Perretta G, Siccardi A, Soprana E, Panigada M, Thom M, Scarselli E, Folgori A, Colloca S, Taylor G, Cortese R, Nicosia A, Capone S, Vitelli A. Mucosal delivery of a vectored RSV vaccine is safe and elicits protective immunity in rodents and nonhuman primates. Mol Ther Methods Clin Dev 2015; 2:15018. [PMID: 26015988 PMCID: PMC4441047 DOI: 10.1038/mtm.2015.18] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2015] [Accepted: 03/20/2015] [Indexed: 01/27/2023]
Abstract
Respiratory Syncytial Virus (RSV) is a leading cause of severe respiratory disease in infants and the elderly. No vaccine is presently available to address this major unmet medical need. We generated a new genetic vaccine based on chimpanzee Adenovirus (PanAd3-RSV) and Modified Vaccinia Ankara RSV (MVA-RSV) encoding the F, N, and M2-1 proteins of RSV, for the induction of neutralizing antibodies and broad cellular immunity. Because RSV infection is restricted to the respiratory tract, we compared intranasal (IN) and intramuscular (M) administration for safety, immunogenicity, and efficacy in different species. A single IN or IM vaccination completely protected BALB/c mice and cotton rats against RSV replication in the lungs. However, only IN administration could prevent infection in the upper respiratory tract. IM vaccination with MVA-RSV also protected cotton rats from lower respiratory tract infection in the absence of detectable neutralizing antibodies. Heterologous prime boost with PanAd3-RSV and MVA-RSV elicited high neutralizing antibody titers and broad T-cell responses in nonhuman primates. In addition, animals primed in the nose developed mucosal IgA against the F protein. In conclusion, we have shown that our vectored RSV vaccine induces potent cellular and humoral responses in a primate model, providing strong support for clinical testing.
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Affiliation(s)
| | | | | | | | | | | | | | | | | | - Alessandra Taglioni
- Cellular Biology and Neurobiology Institute (IBCN) National Research Council of Italy, Rome, Italy
| | - Gemma Perretta
- Cellular Biology and Neurobiology Institute (IBCN) National Research Council of Italy, Rome, Italy
| | | | | | | | | | | | | | | | | | - Riccardo Cortese
- ReiThera Srl, Rome, Italy (former Okairos Srl)
- Keires AG, Basel, Switzerland
| | - Alfredo Nicosia
- ReiThera Srl, Rome, Italy (former Okairos Srl)
- CEINGE, Naples, Italy
- Department of Molecular Medicine and Medical Biotechnology, University Federico II, Naples, Italy
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21
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Kurzweil V, Tang R, Galinski M, Wang K, Zuo F, Cherukuri A, Gasser RA, Malkin E, Sifakis F, Mendel DB, Esser MT. Translational sciences approach to RSV vaccine development. Expert Rev Vaccines 2014; 12:1047-60. [PMID: 24053398 DOI: 10.1586/14760584.2013.824706] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
Respiratory syncytial virus (RSV) is a major cause of lower respiratory tract infections in infants and the elderly. Despite its relatively low degree of antigenic variation, it causes frequent reinfection throughout life. Clinical manifestations of RSV disease and the immune response to infection differ in infants and the elderly, suggesting that vaccines designed to protect these two populations may require different attributes. Here, the authors describe the translational approach of utilizing data from epidemiology studies performed in these populations, the use of RSV diagnostics in clinical practice, lessons learned from previous vaccine clinical trials and the success of palivizumab in prevention of RSV disease in premature and high-risk infants to aid the development of safe and effective RSV vaccines.
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Affiliation(s)
- Vanessa Kurzweil
- Cell and Molecular Biology Group, University of Pennsylvania School of Medicine, Philadelphia, PA 19104, USA
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22
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Eschbaumer M, Law S, Solis C, Chernick A, van der Meer F, Czub M. Rapid detection of neutralizing antibodies against bovine viral diarrhoea virus using quantitative high-content screening. J Virol Methods 2014; 198:56-63. [DOI: 10.1016/j.jviromet.2013.12.017] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2013] [Revised: 11/26/2013] [Accepted: 12/17/2013] [Indexed: 11/29/2022]
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23
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Correia BE, Bates JT, Loomis RJ, Baneyx G, Carrico C, Jardine JG, Rupert P, Correnti C, Kalyuzhniy O, Vittal V, Connell MJ, Stevens E, Schroeter A, Chen M, Macpherson S, Serra AM, Adachi Y, Holmes MA, Li Y, Klevit RE, Graham BS, Wyatt RT, Baker D, Strong RK, Crowe JE, Johnson PR, Schief WR. Proof of principle for epitope-focused vaccine design. Nature 2014; 507:201-6. [PMID: 24499818 PMCID: PMC4260937 DOI: 10.1038/nature12966] [Citation(s) in RCA: 382] [Impact Index Per Article: 38.2] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2013] [Accepted: 12/19/2013] [Indexed: 12/12/2022]
Abstract
Vaccines prevent infectious disease largely by inducing protective neutralizing antibodies against vulnerable epitopes. Multiple major pathogens have resisted traditional vaccine development, although vulnerable epitopes targeted by neutralizing antibodies have been identified for several such cases. Hence, new vaccine design methods to induce epitope-specific neutralizing antibodies are needed. Here we show, with a neutralization epitope from respiratory syncytial virus (RSV), that computational protein design can generate small, thermally and conformationally stable protein scaffolds that accurately mimic the viral epitope structure and induce potent neutralizing antibodies. These scaffolds represent promising leads for research and development of a human RSV vaccine needed to protect infants, young children and the elderly. More generally, the results provide proof of principle for epitope-focused and scaffold-based vaccine design, and encourage the evaluation and further development of these strategies for a variety of other vaccine targets including antigenically highly variable pathogens such as HIV and influenza.
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Affiliation(s)
- Bruno E Correia
- 1] Department of Biochemistry, University of Washington, Seattle, Washington 98195, USA [2] PhD Program in Computational Biology, Instituto Gulbenkian Ciência and Instituto de Tecnologia Química e Biológica, Universidade Nova de Lisboa, Oeiras 2780-157, Portugal [3] Department of Chemical Physiology, The Scripps Research Institute, La Jolla, California 92037, USA
| | - John T Bates
- The Vanderbilt Vaccine Center, Vanderbilt University Medical Center, Nashville, Tennessee 37232, USA
| | - Rebecca J Loomis
- The Children's Hospital of Philadelphia Research Institute, Philadelphia, Pennsylvania 19104, USA
| | - Gretchen Baneyx
- Department of Biochemistry, University of Washington, Seattle, Washington 98195, USA
| | - Chris Carrico
- Division of Basic Sciences, Fred Hutchinson Cancer Research Center, Seattle, Washington 98109-1024, USA
| | - Joseph G Jardine
- 1] Department of Biochemistry, University of Washington, Seattle, Washington 98195, USA [2] Department of Immunology and Microbial Science, The Scripps Research Institute, La Jolla, California 92037, USA [3] IAVI Neutralizing Antibody Center, The Scripps Research Institute, La Jolla, California 92037, USA [4] Center for HIV/AIDS Vaccine Immunology and Immunogen Discovery, The Scripps Research Institute, La Jolla, California 92037, USA
| | - Peter Rupert
- Division of Basic Sciences, Fred Hutchinson Cancer Research Center, Seattle, Washington 98109-1024, USA
| | - Colin Correnti
- Division of Basic Sciences, Fred Hutchinson Cancer Research Center, Seattle, Washington 98109-1024, USA
| | - Oleksandr Kalyuzhniy
- 1] Department of Biochemistry, University of Washington, Seattle, Washington 98195, USA [2] IAVI Neutralizing Antibody Center, The Scripps Research Institute, La Jolla, California 92037, USA [3] Center for HIV/AIDS Vaccine Immunology and Immunogen Discovery, The Scripps Research Institute, La Jolla, California 92037, USA
| | - Vinayak Vittal
- Department of Biochemistry, University of Washington, Seattle, Washington 98195, USA
| | - Mary J Connell
- The Children's Hospital of Philadelphia Research Institute, Philadelphia, Pennsylvania 19104, USA
| | - Eric Stevens
- Department of Biochemistry, University of Washington, Seattle, Washington 98195, USA
| | - Alexandria Schroeter
- Department of Biochemistry, University of Washington, Seattle, Washington 98195, USA
| | - Man Chen
- Vaccine Research Center, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland 20892, USA
| | - Skye Macpherson
- 1] Department of Biochemistry, University of Washington, Seattle, Washington 98195, USA [2] Department of Immunology and Microbial Science, The Scripps Research Institute, La Jolla, California 92037, USA [3] IAVI Neutralizing Antibody Center, The Scripps Research Institute, La Jolla, California 92037, USA [4] Center for HIV/AIDS Vaccine Immunology and Immunogen Discovery, The Scripps Research Institute, La Jolla, California 92037, USA
| | - Andreia M Serra
- 1] Department of Biochemistry, University of Washington, Seattle, Washington 98195, USA [2] IAVI Neutralizing Antibody Center, The Scripps Research Institute, La Jolla, California 92037, USA [3] Center for HIV/AIDS Vaccine Immunology and Immunogen Discovery, The Scripps Research Institute, La Jolla, California 92037, USA
| | - Yumiko Adachi
- 1] Department of Biochemistry, University of Washington, Seattle, Washington 98195, USA [2] IAVI Neutralizing Antibody Center, The Scripps Research Institute, La Jolla, California 92037, USA [3] Center for HIV/AIDS Vaccine Immunology and Immunogen Discovery, The Scripps Research Institute, La Jolla, California 92037, USA
| | - Margaret A Holmes
- 1] Division of Basic Sciences, Fred Hutchinson Cancer Research Center, Seattle, Washington 98109-1024, USA [2]
| | - Yuxing Li
- 1] Department of Immunology and Microbial Science, The Scripps Research Institute, La Jolla, California 92037, USA [2] IAVI Neutralizing Antibody Center, The Scripps Research Institute, La Jolla, California 92037, USA [3] Center for HIV/AIDS Vaccine Immunology and Immunogen Discovery, The Scripps Research Institute, La Jolla, California 92037, USA
| | - Rachel E Klevit
- Department of Biochemistry, University of Washington, Seattle, Washington 98195, USA
| | - Barney S Graham
- Vaccine Research Center, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland 20892, USA
| | - Richard T Wyatt
- 1] Department of Immunology and Microbial Science, The Scripps Research Institute, La Jolla, California 92037, USA [2] IAVI Neutralizing Antibody Center, The Scripps Research Institute, La Jolla, California 92037, USA [3] Center for HIV/AIDS Vaccine Immunology and Immunogen Discovery, The Scripps Research Institute, La Jolla, California 92037, USA
| | - David Baker
- Department of Biochemistry, University of Washington, Seattle, Washington 98195, USA
| | - Roland K Strong
- Division of Basic Sciences, Fred Hutchinson Cancer Research Center, Seattle, Washington 98109-1024, USA
| | - James E Crowe
- 1] The Vanderbilt Vaccine Center, Vanderbilt University Medical Center, Nashville, Tennessee 37232, USA [2] Department of Pathology, Microbiology and Immunology, Vanderbilt Medical Center, Nashville, Tennessee 37232, USA [3] Department of Pediatrics, Vanderbilt Medical Center, Nashville, Tennessee 37232, USA
| | - Philip R Johnson
- The Children's Hospital of Philadelphia Research Institute, Philadelphia, Pennsylvania 19104, USA
| | - William R Schief
- 1] Department of Biochemistry, University of Washington, Seattle, Washington 98195, USA [2] Department of Immunology and Microbial Science, The Scripps Research Institute, La Jolla, California 92037, USA [3] IAVI Neutralizing Antibody Center, The Scripps Research Institute, La Jolla, California 92037, USA [4] Center for HIV/AIDS Vaccine Immunology and Immunogen Discovery, The Scripps Research Institute, La Jolla, California 92037, USA
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Immunogenicity of novel mumps vaccine candidates generated by genetic modification. J Virol 2013; 88:2600-10. [PMID: 24352450 DOI: 10.1128/jvi.02778-13] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023] Open
Abstract
Mumps is a highly contagious human disease, characterized by lateral or bilateral nonsuppurative swelling of the parotid glands and neurological complications that can result in aseptic meningitis or encephalitis. A mumps vaccination program implemented since the 1960s reduced mumps incidence by more than 99% and kept the mumps case numbers as low as hundreds of cases per year in the United States before 2006. However, a large mumps outbreak occurred in vaccinated populations in 2006 and again in 2009 in the United States, raising concerns about the efficacy of the vaccination program. Previously, we have shown that clinical isolate-based recombinant mumps viruses lacking expression of either the V protein (rMuVΔV) or the SH protein (rMuVΔSH) are attenuated in a neurovirulence test using newborn rat brains (P. Xu et al., Virology 417:126-136, 2011, http://dx.doi.org/10.1016/j.virol.2011.05.003; P. Xu et al., J. Virol. 86:1768-1776, 2012, http://dx.doi.org/10.1128/JVI.06019-11) and may be good candidates for vaccine development. In this study, we examined immunity induced by rMuVΔSH and rMuVΔV in mice. Furthermore, we generated recombinant mumps viruses lacking expression of both the V protein and the SH protein (rMuVΔSHΔV). Analysis of rMuVΔSHΔV indicated that it was stable in tissue culture cell lines. Importantly, rMuVΔSHΔV was immunogenic in mice, indicating that it is a promising candidate for mumps vaccine development.
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Recent advances in diagnosis, prevention, and treatment of human respiratory syncytial virus. Adv Virol 2013; 2013:595768. [PMID: 24382964 PMCID: PMC3872095 DOI: 10.1155/2013/595768] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2013] [Accepted: 09/30/2013] [Indexed: 12/25/2022] Open
Abstract
Human respiratory syncytial virus (RSV) is a common cause of respiratory infection in infants and the elderly, leading to significant morbidity and mortality. The interdisciplinary fields, especially biotechnology and nanotechnology, have facilitated the development of modern detection systems for RSV. Many anti-RSV compounds like fusion inhibitors and RNAi molecules have been successful in laboratory and clinical trials. But, currently, there are no effective drugs for RSV infection even after decades of research. Effective diagnosis can result in effective treatment, but the progress in both of these facets must be concurrent. The development in prevention and treatment measures for RSV is at appreciable pace, but the implementation into clinical practice still seems a challenge. This review attempts to present the promising diverse research approaches and advancements in the area of diagnosis, prevention, and treatment that contribute to RSV management.
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Fuentes S, Crim RL, Beeler J, Teng MN, Golding H, Khurana S. Development of a simple, rapid, sensitive, high-throughput luciferase reporter based microneutralization test for measurement of virus neutralizing antibodies following Respiratory Syncytial Virus vaccination and infection. Vaccine 2013; 31:3987-94. [PMID: 23742994 PMCID: PMC3779065 DOI: 10.1016/j.vaccine.2013.05.088] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2013] [Revised: 05/13/2013] [Accepted: 05/21/2013] [Indexed: 01/03/2023]
Abstract
We have established a new reporter gene-based RSV neutralization test using Renilla luciferase. The RSV-Luciferase Neutralization Test (RSV-Luc-NeuT) is a simple, rapid, high throughput, and less labor intensive functional serological assay than the traditional RSV-PRNT, capable of measuring a broad range of anti-RSV neutralizing antibodies targeting both RSV-F and RSV-G proteins. Specificity and sensitivity of the RSV-Luc-NeuT are comparable to the RSV-PRNT. Panels of pre-vaccination and post-vaccination animal sera, monoclonal antibodies and animal polyclonal anti-RSV sera confirmed assay specificity. A panel of 60 human sera demonstrated high assay sensitivity for measurement of RSV neutralizing antibodies that strongly correlated with the RSV-PRNT titers (R(2)=0.864). Neutralization in the presence of guinea pig complement (GPC) increased PRNT titers more than the RSV-Luc-NeuT neutralizing antibody titers for these human sera. This newly developed simple, high throughput, RSV-Luc-NeuT could be easily automated and applied in measurement of RSV neutralization titers in large vaccine trials.
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Affiliation(s)
- Sandra Fuentes
- Division of Viral Products, Center for Biologics Evaluation and Research (CBER), FDA, Bethesda, MD 20892, USA
| | - Roberta L. Crim
- Division of Viral Products, Center for Biologics Evaluation and Research (CBER), FDA, Bethesda, MD 20892, USA
| | - Judy Beeler
- Division of Viral Products, Center for Biologics Evaluation and Research (CBER), FDA, Bethesda, MD 20892, USA
| | - Michael N. Teng
- Division of Allergy & Immunology, Department of Internal Medicine, University of South Florida, Tampa, FL 33612, USA
| | - Hana Golding
- Division of Viral Products, Center for Biologics Evaluation and Research (CBER), FDA, Bethesda, MD 20892, USA
| | - Surender Khurana
- Division of Viral Products, Center for Biologics Evaluation and Research (CBER), FDA, Bethesda, MD 20892, USA
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27
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Varada JC, Teferedegne B, Crim RL, Mdluli T, Audet S, Peden K, Beeler J, Murata H. A neutralization assay for respiratory syncytial virus using a quantitative PCR-based endpoint assessment. Virol J 2013; 10:195. [PMID: 23767960 PMCID: PMC3686610 DOI: 10.1186/1743-422x-10-195] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2013] [Accepted: 06/11/2013] [Indexed: 11/22/2022] Open
Abstract
Background Few studies have used quantitative polymerase chain reaction (qPCR) as an approach to measure virus neutralization assay endpoints. Its lack of use may not be surprising considering that sample nucleic acid extraction and purification can be expensive, labor-intensive, and rate-limiting. Methods Virus/antibody mixtures were incubated for one hour at 37°C and then transferred to Vero cell monolayers in a 96-well plate format. At 24 (or 48) hours post-infection, we used a commercially available reagent to prepare cell lysates amenable to direct analysis by one-step SYBR Green quantitative reverse transcription PCR using primers specific for the RSV-N gene, thereby obviating the need for cumbersome RNA extraction and purification. The neutralization titer was defined as the reciprocal of the highest dilution needed to inhibit the PCR signal by 90% when compared with the mean value observed in virus control wells in the absence of neutralizing antibodies. Results We have developed a qPCR-based neutralization assay for human respiratory syncytial virus. Due to the sensitivity of qPCR in detecting virus replication, endpoints may be assessed as early as 24 hours post-infection. In addition, the dynamic range of qPCR provides a basis for the assay to be relatively robust to perturbations in input virus dose (i.e., the assay is in compliance with the Percentage Law). Conclusions This qPCR-based neutralization assay is suitable for automated high-throughput applications. In addition, our experimental approach may be generalizable for the rapid development of neutralization assays for other virus families.
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Affiliation(s)
- Jan C Varada
- Laboratory of DNA Viruses, Division of Viral Products, OVRR, CBER, FDA, Bethesda, MD 20892, USA
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28
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McLellan JS, Chen M, Leung S, Graepel KW, Du X, Yang Y, Zhou T, Baxa U, Yasuda E, Beaumont T, Kumar A, Modjarrad K, Zheng Z, Zhao M, Xia N, Kwong PD, Graham BS. Structure of RSV fusion glycoprotein trimer bound to a prefusion-specific neutralizing antibody. Science 2013; 340:1113-7. [PMID: 23618766 PMCID: PMC4459498 DOI: 10.1126/science.1234914] [Citation(s) in RCA: 576] [Impact Index Per Article: 52.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
The prefusion state of respiratory syncytial virus (RSV) fusion (F) glycoprotein is the target of most RSV-neutralizing activity in human sera, but its metastability has hindered characterization. To overcome this obstacle, we identified prefusion-specific antibodies that were substantially more potent than the prophylactic antibody palivizumab. The cocrystal structure for one of these antibodies, D25, in complex with the F glycoprotein revealed D25 to lock F in its prefusion state by binding to a quaternary epitope at the trimer apex. Electron microscopy showed that two other antibodies, AM22 and 5C4, also bound to the newly identified site of vulnerability, which we named antigenic site Ø. These studies should enable design of improved vaccine antigens and define new targets for passive prevention of RSV-induced disease.
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Affiliation(s)
- Jason S. McLellan
- Vaccine Research Center, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD 20892, USA
| | - Man Chen
- Vaccine Research Center, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD 20892, USA
| | - Sherman Leung
- Vaccine Research Center, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD 20892, USA
| | - Kevin W. Graepel
- Vaccine Research Center, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD 20892, USA
| | - Xiulian Du
- Vaccine Research Center, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD 20892, USA
| | - Yongping Yang
- Vaccine Research Center, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD 20892, USA
| | - Tongqing Zhou
- Vaccine Research Center, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD 20892, USA
| | - Ulrich Baxa
- Electron Microscopy Laboratory, Advanced Technology Program, SAIC-Frederick, Inc, Frederick National Laboratory for Cancer Research, Frederick, MD 21702, USA
| | - Etsuko Yasuda
- AIMM Therapeutics, Academic Medical Center, Amsterdam, The Netherlands
| | - Tim Beaumont
- AIMM Therapeutics, Academic Medical Center, Amsterdam, The Netherlands
| | - Azad Kumar
- Vaccine Research Center, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD 20892, USA
| | - Kayvon Modjarrad
- Vaccine Research Center, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD 20892, USA
| | - Zizheng Zheng
- National Institute of Diagnostics and Vaccine Development in Infectious Diseases, Xiamen University, Xiamen, China, 361005
| | - Min Zhao
- National Institute of Diagnostics and Vaccine Development in Infectious Diseases, Xiamen University, Xiamen, China, 361005
| | - Ningshao Xia
- National Institute of Diagnostics and Vaccine Development in Infectious Diseases, Xiamen University, Xiamen, China, 361005
| | - Peter D. Kwong
- Vaccine Research Center, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD 20892, USA
| | - Barney S. Graham
- Vaccine Research Center, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD 20892, USA
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Wang KC, Chang JS, Lin LT, Chiang LC, Lin CC. Antiviral effect of cimicifugin from Cimicifuga foetida against human respiratory syncytial virus. THE AMERICAN JOURNAL OF CHINESE MEDICINE 2012; 40:1033-45. [PMID: 22928833 DOI: 10.1142/s0192415x12500760] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
Human respiratory syncytial virus (RSV) causes serious infection of the lower respiratory tract in children and an effective antiviral therapy against the viral pathogen remains unavailable. We previously demonstrated that the oriental medicinal plant, Cimicifuga foetida L. (C. foetida), possessed inhibitory activity against RSV. Since cimicifugin is a major constituent of C. foetida, we sought to examine in this study its anti-RSV effect on both the human upper (HEp-2) and lower (A549) respiratory tract cell lines. Results revealed that cimicifugin dose-dependently inhibited RSV-induced plaque formation in both HEp-2 and A549 cells (p < 0.0001), with a superior effect in the latter cell type (p < 0.0001). The antiviral activity of cimicifugin was time-dependent (p < 0.0001) and was most effective when cells were treated with the compound before viral inoculation. Additional experiments demonstrated that cimicifugin could inhibit viral attachment (p < 0.0001) and viral internalization (p < 0.0001). Furthermore, the drug could potentiate heparin's effect against attachment of RSV, particularly in A549 cells. Enzyme-linked immunosorbent assay (ELISA) analysis of antiviral cytokines induction revealed that cimicifugin could also stimulate epithelial cells to secrete IFN-β to counteract viral infection. Taken together, these results indicate that cimicifugin is an efficient antiviral agent against RSV infection. We suggest that cimicifugin might be useful for the management of RSV pathogenesis.
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Affiliation(s)
- Kuo-Chih Wang
- Graduate Institute of Natural Products, School of Pharmacy, College of Pharmacy, Kaohsiung Medical University, Taiwan
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van Remmerden Y, Xu F, van Eldik M, Heldens JGM, Huisman W, Widjojoatmodjo MN. An improved respiratory syncytial virus neutralization assay based on the detection of green fluorescent protein expression and automated plaque counting. Virol J 2012; 9:253. [PMID: 23114196 PMCID: PMC3514128 DOI: 10.1186/1743-422x-9-253] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2011] [Accepted: 10/17/2012] [Indexed: 12/01/2022] Open
Abstract
Background Virus neutralizing antibodies against respiratory syncytial virus (RSV) are considered important correlates of protection for vaccine evaluation. The established plaque reduction assay is time consuming, labor intensive and highly variable. Methods Here, a neutralization assay based on a modified RSV strain expressing the green fluorescent protein in combination with automated detection and quantification of plaques is described. Results The fluorescence plaque reduction assay in microplate format requires only two days to complete and is simple and reproducible. A good correlation between visual and automated counting methods to determine RSV neutralizing serum antibody titers was observed. Conclusions The developed virus neutralization assay is suitable for high-throughput testing and can be used for both animal studies and (large scale) vaccine clinical trials.
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Affiliation(s)
- Yvonne van Remmerden
- Department of Vaccine Research, Vaccinology, National Institute for Public Health and the Environment, Bilthoven, The Netherlands
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31
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Wang KC, Chang JS, Chiang LC, Lin CC. Cimicifuga foetida L. inhibited human respiratory syncytial virus in HEp-2 and A549 cell lines. THE AMERICAN JOURNAL OF CHINESE MEDICINE 2012; 40:151-62. [PMID: 22298455 DOI: 10.1142/s0192415x12500127] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Human respiratory syncytial virus (HRSV) causes serious pediatric infection of the lower respiratory tract without effective therapeutic modality. Sheng-Ma-Ge-Gen-Tang (SMGGT; Shoma-kakkon-to) has been proven to be effective at inhibiting HRSV-induced plaque formation, and Cimicifuga foetida is the major constituent of SMGGT. We tested the hypothesis that C. foetida effectively inhibited the cytopathic effects of HRSV by a plaque reduction assay in both human upper (HEp2) and lower (A549) respiratory tract cell lines. Its ability to stimulate anti-viral cytokines was evaluated by an enzyme-linked immunosorbent assay (ELISA). C. foetida dose-dependently inhibited HRSV-induced plaque formation (p < 0.0001) before and after viral inoculation, especially in A549 cells (p < 0.0001). C. foetida dose-dependently inhibited viral attachment (p < 0.0001) and could increase heparins effect on viral attachment. In addition, C. foetida time-dependently and dose-dependently (p < 0.0001) inhibited HRSV internalization. C. foetida could stimulate epithelial cells to secrete IFN-β to counteract viral infection. However, C. foetida did not stimulate TNF-α secretion. Therefore, C. foetida could be useful in managing HRSV infection. This is the first evidence to support that C. foetida possesses antiviral activity.
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Affiliation(s)
- Kuo Chih Wang
- Graduate Institute of Natural Products, College of Pharmacy, Kaohsiung Medical University, 100 Shih-Chuan 1st Road, Kaohsiung, Taiwan
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Luchsinger V, Piedra PA, Ruiz M, Zunino E, Martínez MA, Machado C, Fasce R, Ulloa MT, Fink MC, Lara P, Avendaño LF. Role of neutralizing antibodies in adults with community-acquired pneumonia by respiratory syncytial virus. Clin Infect Dis 2012; 54:905-12. [PMID: 22238168 PMCID: PMC7107950 DOI: 10.1093/cid/cir955] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
Background. Respiratory syncytial virus (RSV) has been implicated in the etiology of adult community-acquired pneumonia (CAP). We investigated RSV infection in Chilean adults with CAP using direct viral detection, real-time reverse-transcription polymerase chain reaction (rtRT-PCR), and serology (microneutralization assay). Methods. RSV, other respiratory viruses, and bacteria were studied by conventional and molecular techniques in adults aged ≥18 years presenting with CAP to the healthcare facilities in Santiago, Chile from February 2005 through December 2007. Results. All 356 adults with CAP enrolled had an acute blood sample collected at enrollment, and 184 had a convalescent blood sample. RSV was detected in 48 cases (13.4%). Immunofluorescence assay and viral isolation each detected only 1 infection (0.2%), whereas rtRT-PCR was positive in 32 (8.9%) cases and serology was positive in 20 (10.8%) cases. CAP clinical characteristics were similar in RSV-infected and non-RSV-infected cases. RSV-specific geometric mean serum-neutralizing antibody titer (GMST) was significantly lower at admission in the 48 RSV-infected cases compared with 308 non-RSV-infected adults (GMST in log2: RSV/A 8.1 vs 8.9, and RSV/B 9.3 vs 10.4; P < .02). Conclusions. RSV infection is frequent in Chilean adults with CAP. Microneutralization assay was as sensitive as rtRT-PCR in detecting RSV infection and is a good adjunct assay for diagnostic research. High RSV-specific serum-neutralizing antibody levels were associated with protection against common and severe infection. The development of a vaccine could prevent RSV-related CAP in adults.
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Affiliation(s)
- Vivian Luchsinger
- Programa de Virología, Facultad de Medicina, Universidad de Chile, Santiago, Chile.
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Chang JS, Wang KC, Shieh DE, Chiang LC. Liu-He-Tang inhibited plaque formation by human respiratory syncytial virus infection in cell lines of the human respiratory tract. JOURNAL OF ETHNOPHARMACOLOGY 2011; 137:1149-1155. [PMID: 21810459 DOI: 10.1016/j.jep.2011.07.043] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/23/2011] [Revised: 07/11/2011] [Accepted: 07/17/2011] [Indexed: 05/31/2023]
Abstract
ETHNOPHARMACOLOGICAL RELEVANCE Liu-He-Tang (LHT) has been used to treat adult respiratory tract infection with productive cough and fever for a thousand years in ancient China. Adults with respiratory tract infection of human respiratory syncytial virus (HRSV) can have symptoms similar to those managed by LHT. Therefore, LHT is supposed to be beneficial for adult HRSV infection. However, LHT does not have any antiviral activity to support its use against HRSV infection. AIM OF THE STUDY HRSV is the most important virus causing serious pediatric respiratory tract infections worldwide. HRSV also contributes considerably to respiratory tract illness in adults. There is no effective therapeutic modality against HRSV infection. In order to find readily available agents to manage adult HRSV infection, this study tested the hypothesis that LHT has antiviral activity against HRSV-induced cytopathy. MATERIALS AND METHODS Effect of the hot water extract of LHT on HRSV was tested by plaque reduction assay in both human upper (HEp-2) and low (A549) respiratory tract cell lines and also a human normal fibroblast cell line (WI-38). Ability of LHT to stimulate anti-viral cytokines was evaluated by enzyme-linked immunosorbent assay (ELISA). RESULTS LHT could dose-dependently inhibit HRSV-induced plaque formation (p < 0.0001), especially in A549 cell. 300 μg/ml LHT nearly abolished plaque formation in A549 cells. LHT was more effective when given before viral inoculation (p < 0.0001). LHT dose-dependently inhibited viral attachment (p < 0.0001). Besides, LHT could inhibit HRSV internalization both time-dependently and dose-dependently (p < 0.0001). Furthermore, LHT stimulated epithelial cells to secrete IFN-β and TNF-α to counteract HRSV infection before infection becomes established. CONCLUSIONS LHT has anti-HRSV activity that provides a basic support of its possible use in managing adult HRSV infection.
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Affiliation(s)
- Jung San Chang
- Department of Renal Care, College of Medicine, Kaohsiung Medical University, Ping-Tung 907, Taiwan
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McLellan JS, Correia BE, Chen M, Yang Y, Graham BS, Schief WR, Kwong PD. Design and characterization of epitope-scaffold immunogens that present the motavizumab epitope from respiratory syncytial virus. J Mol Biol 2011; 409:853-66. [PMID: 21549714 PMCID: PMC3107930 DOI: 10.1016/j.jmb.2011.04.044] [Citation(s) in RCA: 94] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2011] [Revised: 04/15/2011] [Accepted: 04/15/2011] [Indexed: 10/18/2022]
Abstract
Respiratory syncytial virus (RSV) is a major cause of respiratory tract infections in infants, but an effective vaccine has not yet been developed. An ideal vaccine would elicit protective antibodies while avoiding virus-specific T-cell responses, which have been implicated in vaccine-enhanced disease with previous RSV vaccines. We propose that heterologous proteins designed to present RSV-neutralizing antibody epitopes and to elicit cognate antibodies have the potential to fulfill these vaccine requirements, as they can be fashioned to be free of viral T-cell epitopes. Here we present the design and characterization of three epitope-scaffolds that present the epitope of motavizumab, a potent neutralizing antibody that binds to a helix-loop-helix motif in the RSV fusion glycoprotein. Two of the epitope-scaffolds could be purified, and one epitope-scaffold based on a Staphylococcus aureus protein A domain bound motavizumab with kinetic and thermodynamic properties consistent with the free epitope-scaffold being stabilized in a conformation that closely resembled the motavizumab-bound state. This epitope-scaffold was well folded as assessed by circular dichroism and isothermal titration calorimetry, and its crystal structure (determined in complex with motavizumab to 1.9 Å resolution) was similar to the computationally designed model, with all hydrogen-bond interactions critical for binding to motavizumab preserved. Immunization of mice with this epitope-scaffold failed to elicit neutralizing antibodies but did elicit sera with F binding activity. The elicitation of F binding antibodies suggests that some of the design criteria for eliciting protective antibodies without virus-specific T-cell responses are being met, but additional optimization of these novel immunogens is required.
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Affiliation(s)
- Jason S McLellan
- Vaccine Research Center, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD 20892, USA.
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35
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Wang KC, Chang JS, Chiang LC, Lin CC. Sheng-Ma-Ge-Gen-Tang (Shoma-kakkon-to) inhibited cytopathic effect of human respiratory syncytial virus in cell lines of human respiratory tract. JOURNAL OF ETHNOPHARMACOLOGY 2011; 135:538-544. [PMID: 21463671 DOI: 10.1016/j.jep.2011.03.058] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/03/2010] [Revised: 03/25/2011] [Accepted: 03/27/2011] [Indexed: 05/30/2023]
Abstract
ETHNOPHARMACOLOGICAL RELEVANCE Sheng-Ma-Ge-Gen-Tang (SMGGT; Shoma-kakkon-to) has been used against pediatric viral infection for thousands of year in ancient China. However, it is unknown whether SMGGT is effective against human respiratory syncytial virus (HRSV). AIM OF THE STUDY HRSV is a major pediatric viral pathogen of low respiratory tract infection without effective management. This study tested the hypothesis that SMGGT effectively inhibited cytopathy induced by HRSV. MATERIALS AND METHODS Effect of the crude extract of SMGGT on HRSV was tested by plaque reduction assay in both human upper (HEp-2) and low (A549) respiratory tract cell lines. Ability of SMGGT to stimulate anti-viral cytokines was evaluated by enzyme-linked immunosorbent assay (ELISA). RESULTS Crude extract of SMGGT dose-dependently inhibited HRSV-induced plaque formation. The crude extract was more effective when given before viral infection (p<0.0001). It inhibited viral attachment dose-dependently (p<0.0001) and could increase heparin effect on viral attachment. Furthermore, it was synergistic with very low-dose heparin on viral attachment. In addition, the crude extract time-dependently and dose-dependently (p<0.0001) inhibited HRSV internalization into HEp-2 cells. Epithelial cells secrete IFN-β and TNF-α to counteract viral infection. The crude extract could stimulate epithelial cells to secrete these cytokines beforehand and become resistant to viral infection. It also stimulated IFN-β to defense HRSV after viral inoculation. CONCLUSIONS Sheng-Ma-Ge-Gen-Tang could be effective to manage HRSV infection in young children.
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Affiliation(s)
- Kuo-Chih Wang
- Graduate Institute of Natural Products, College of Pharmacy, Kaohsiung Medical University, 100 Shih-Chuan 1st Road, Kaohsiung 80708, Taiwan
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McLellan JS, Chen M, Chang JS, Yang Y, Kim A, Graham BS, Kwong PD. Structure of a major antigenic site on the respiratory syncytial virus fusion glycoprotein in complex with neutralizing antibody 101F. J Virol 2010; 84:12236-44. [PMID: 20881049 PMCID: PMC2976384 DOI: 10.1128/jvi.01579-10] [Citation(s) in RCA: 92] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2010] [Accepted: 09/20/2010] [Indexed: 11/20/2022] Open
Abstract
Respiratory syncytial virus (RSV) is a major cause of pneumonia and bronchiolitis in infants and elderly people. Currently there is no effective vaccine against RSV, but passive prophylaxis with neutralizing antibodies reduces hospitalizations. To investigate the mechanism of antibody-mediated RSV neutralization, we undertook structure-function studies of monoclonal antibody 101F, which binds a linear epitope in the RSV fusion glycoprotein. Crystal structures of the 101F antigen-binding fragment in complex with peptides from the fusion glycoprotein defined both the extent of the linear epitope and the interactions of residues that are mutated in antibody escape variants. The structure allowed for modeling of 101F in complex with trimers of the fusion glycoprotein, and the resulting models suggested that 101F may contact additional surfaces located outside the linear epitope. This hypothesis was supported by surface plasmon resonance experiments that demonstrated 101F bound the peptide epitope ∼16,000-fold more weakly than the fusion glycoprotein. The modeling also showed no substantial clashes between 101F and the fusion glycoprotein in either the pre- or postfusion state, and cell-based assays indicated that 101F neutralization was not associated with blocking virus attachment. Collectively, these results provide a structural basis for RSV neutralization by antibodies that target a major antigenic site on the fusion glycoprotein.
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Affiliation(s)
- Jason S McLellan
- Vaccine Research Center, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland 20892, USA.
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