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van Dijk LLA, Rijsbergen LC, Rubio BT, Schmitz KS, Gommers L, Comvalius AD, Havelaar A, van Amerongen G, Schepp R, Lamers MM, GeurtsvanKessel CH, Haagmans BL, van Binnendijk R, de Swart RL, de Vries RD. Virus neutralization assays for human respiratory syncytial virus using airway organoids. Cell Mol Life Sci 2024; 81:267. [PMID: 38884678 PMCID: PMC11335194 DOI: 10.1007/s00018-024-05307-y] [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: 03/15/2024] [Revised: 05/23/2024] [Accepted: 06/04/2024] [Indexed: 06/18/2024]
Abstract
Neutralizing antibodies are considered a correlate of protection against severe human respiratory syncytial virus (HRSV) disease. Currently, HRSV neutralization assays are performed on immortalized cell lines like Vero or A549 cells. It is known that assays on these cell lines exclusively detect neutralizing antibodies (nAbs) directed to the fusion (F) protein. For the detection of nAbs directed to the glycoprotein (G), ciliated epithelial cells expressing the cellular receptor CX3CR1 are required, but generation of primary cell cultures is expensive and labor-intensive. Here, we developed a high-throughput neutralization assay based on the interaction between clinically relevant HRSV grown on primary cells with ciliated epithelial cells, and validated this assay using a panel of infant sera. To develop the high-throughput neutralization assay, we established a culture of differentiated apical-out airway organoids (Ap-O AO). CX3CR1 expression was confirmed, and both F- and G-specific monoclonal antibodies neutralized HRSV in the Ap-O AO. In a side-by-side neutralization assay on Vero cells and Ap-O AO, neutralizing antibody levels in sera from 125 infants correlated well, although titers on Ap-O AO were consistently lower. We speculate that these lower titers might be an actual reflection of the neutralizing antibody capacity in vivo. The organoid-based neutralization assay described here holds promise for further characterization of correlates of protection against HRSV disease.
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Affiliation(s)
- Laura L A van Dijk
- Department of Viroscience, Erasmus MC, University Medical Centre Rotterdam, Rotterdam, the Netherlands
| | - Laurine C Rijsbergen
- Department of Viroscience, Erasmus MC, University Medical Centre Rotterdam, Rotterdam, the Netherlands
| | - Bruno Tello Rubio
- Department of Viroscience, Erasmus MC, University Medical Centre Rotterdam, Rotterdam, the Netherlands
| | - Katharina S Schmitz
- Department of Viroscience, Erasmus MC, University Medical Centre Rotterdam, Rotterdam, the Netherlands
| | - Lennert Gommers
- Department of Viroscience, Erasmus MC, University Medical Centre Rotterdam, Rotterdam, the Netherlands
| | - Anouskha D Comvalius
- Department of Viroscience, Erasmus MC, University Medical Centre Rotterdam, Rotterdam, the Netherlands
| | - Alexander Havelaar
- Department of Viroscience, Erasmus MC, University Medical Centre Rotterdam, Rotterdam, the Netherlands
| | - Geert van Amerongen
- Department of Viroscience, Erasmus MC, University Medical Centre Rotterdam, Rotterdam, the Netherlands
| | - Rutger Schepp
- Center of Infectious Disease Control, National Institute of Public Health and the Environment (RIVM), Bilthoven, the Netherlands
| | - Mart M Lamers
- Department of Viroscience, Erasmus MC, University Medical Centre Rotterdam, Rotterdam, the Netherlands
- Programme in Emerging Infectious Diseases, Duke-NUS Medical School, Singapore, Singapore
| | - Corine H GeurtsvanKessel
- Department of Viroscience, Erasmus MC, University Medical Centre Rotterdam, Rotterdam, the Netherlands
| | - Bart L Haagmans
- Department of Viroscience, Erasmus MC, University Medical Centre Rotterdam, Rotterdam, the Netherlands
| | - Rob van Binnendijk
- Center of Infectious Disease Control, National Institute of Public Health and the Environment (RIVM), Bilthoven, the Netherlands
| | - Rik L de Swart
- Department of Viroscience, Erasmus MC, University Medical Centre Rotterdam, Rotterdam, the Netherlands
| | - Rory D de Vries
- Department of Viroscience, Erasmus MC, University Medical Centre Rotterdam, Rotterdam, the Netherlands.
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2
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Xiong Y, Tao K, Li T, Ou W, Zhou Y, Zhang W, Wang S, Qi R, Ji J. Resveratrol inhibits respiratory syncytial virus replication by targeting heparan sulfate proteoglycans. Food Funct 2024; 15:1948-1962. [PMID: 38270052 DOI: 10.1039/d3fo05131e] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2024]
Abstract
Resveratrol, renowned as an antioxidant, also exhibits significant potential in combatting severe respiratory infections, particularly the respiratory syncytial virus (RSV). Nevertheless, the specific mechanism underlying its inhibition of RSV replication remains unexplored. Heparan sulfate proteoglycans (HSPGs) play a pivotal role as attachment factors for numerous viruses, offering a promising avenue for countering viral infections. Our research has unveiled that resveratrol effectively curbs RSV infection in a dose-dependent manner. Remarkably, resveratrol disrupts the early stages of RSV infection by engaging with HSPGs, rather than interacting with RSV surface proteins like fusion (F) protein and glycoprotein (G). Resveratrol's affinity appears to be predominantly directed towards the negatively charged sites on HSPGs, thus impeding the binding of viral receptors. In an in vivo study involving RSV-infected mice, resveratrol demonstrates its potential by ameliorating pulmonary pathology. This improvement is attributed to the inhibition of pro-inflammatory cytokine expression and a reduction in viral load within the lungs. Notably, resveratrol specifically alleviates inflammation characterized by an abundance of neutrophils in RSV-infected mice. In summation, our data first shows how resveratrol combats RSV infection through interactions with HSPGs, positioning it as a promising candidate for innovative drug development targeting RSV infections. Our study provides insight into the mechanism of resveratrol antiviral infection.
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Affiliation(s)
- Yingcai Xiong
- Jiangsu Key Laboratory of Pediatric Respiratory Disease, Institute of Pediatrics, Nanjing University of Chinese Medicine, 138 Xianlin Avenue, Nanjing, 210023, China.
- School of Medicine, Nanjing University of Chinese Medicine, 138 Xianlin Avenue, Nanjing, 210023, China.
| | - Keyu Tao
- Jiangsu Key Laboratory of Pediatric Respiratory Disease, Institute of Pediatrics, Nanjing University of Chinese Medicine, 138 Xianlin Avenue, Nanjing, 210023, China.
- School of Medicine, Nanjing University of Chinese Medicine, 138 Xianlin Avenue, Nanjing, 210023, China.
| | - Tao Li
- Jiangsu Key Laboratory of Pediatric Respiratory Disease, Institute of Pediatrics, Nanjing University of Chinese Medicine, 138 Xianlin Avenue, Nanjing, 210023, China.
| | - Weiying Ou
- Jiangsu Key Laboratory of Pediatric Respiratory Disease, Institute of Pediatrics, Nanjing University of Chinese Medicine, 138 Xianlin Avenue, Nanjing, 210023, China.
| | - Yinghui Zhou
- Jiangsu Key Laboratory of Pediatric Respiratory Disease, Institute of Pediatrics, Nanjing University of Chinese Medicine, 138 Xianlin Avenue, Nanjing, 210023, China.
| | - Wenyang Zhang
- Jiangsu Key Laboratory of Pediatric Respiratory Disease, Institute of Pediatrics, Nanjing University of Chinese Medicine, 138 Xianlin Avenue, Nanjing, 210023, China.
| | - Shouchuan Wang
- Jiangsu Key Laboratory of Pediatric Respiratory Disease, Institute of Pediatrics, Nanjing University of Chinese Medicine, 138 Xianlin Avenue, Nanjing, 210023, China.
| | - Ruogu Qi
- School of Medicine, Nanjing University of Chinese Medicine, 138 Xianlin Avenue, Nanjing, 210023, China.
| | - Jianjian Ji
- Jiangsu Key Laboratory of Pediatric Respiratory Disease, Institute of Pediatrics, Nanjing University of Chinese Medicine, 138 Xianlin Avenue, Nanjing, 210023, China.
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3
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Kim MJ, Chu KB, Lee SH, Mao J, Eom GD, Yoon KW, Moon EK, Quan FS. Assessing the protection elicited by virus-like particles expressing the RSV pre-fusion F and tandem repeated G proteins against RSV rA2 line19F infection in mice. Respir Res 2024; 25:7. [PMID: 38178222 PMCID: PMC10765939 DOI: 10.1186/s12931-023-02641-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2023] [Accepted: 12/15/2023] [Indexed: 01/06/2024] Open
Abstract
Excessive pulmonary inflammation is the hallmark of respiratory syncytial virus (RSV) infection hindering efficacious RSV vaccine development. Yet, the vast majority of the experimental RSV vaccine studies use laboratory-adapted RSV strains that do not reflect the highly pathogenic and inflammatory nature of the virus found in clinical settings. Here, we re-evaluated the protective efficacy of the virus-like particle (VLP) vaccine co-expressing the pre-fusion (pre-F) protein and G protein with tandem repeats (Gt) reported in our previous study against the recombinant RSV rA2-line19F strain, which inflicts severe mucus production and inflammation in mice. VLP vaccine immunization elicited virus-specific serum antibody responses that mediated RSV rA2-line19F virus neutralization. VLP vaccine immunization promoted Th1 immune response development in the spleens and CD8 + T cell influx into the lungs of mice, which are essential for efficient viral clearance and dampened inflammatory response. When compared to the VLPs expressing only the pre-F antigen, those co-expressing both pre-F and Gt antigens conferred better protection in mice against rA2-line19F challenge infection. Overall, our data suggest that the pre-clinical VLP vaccine co-expressing RSV pre-F and Gt antigens can effectively protect mice against RSV strains that resemble pathogenic clinical isolates.
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Affiliation(s)
- Min-Ju Kim
- Department of Biomedical Science, Graduate School, Kyung Hee University, Seoul, 02447, Republic of Korea
| | - Ki Back Chu
- Medical Research Center for Bioreaction to Reactive Oxygen Species and Biomedical Science Institute, Core Research Institute (CRI), Kyung Hee University, Seoul, 02447, Republic of Korea
| | - Su-Hwa Lee
- Department of Medical Zoology, School of Medicine, Kyung Hee University, Seoul, 02447, Republic of Korea
| | - Jie Mao
- Department of Biomedical Science, Graduate School, Kyung Hee University, Seoul, 02447, Republic of Korea
| | - Gi-Deok Eom
- Department of Biomedical Science, Graduate School, Kyung Hee University, Seoul, 02447, Republic of Korea
| | - Keon-Woong Yoon
- Department of Biomedical Science, Graduate School, Kyung Hee University, Seoul, 02447, Republic of Korea
| | - Eun-Kyung Moon
- Department of Medical Zoology, School of Medicine, Kyung Hee University, Seoul, 02447, Republic of Korea
| | - Fu-Shi Quan
- Medical Research Center for Bioreaction to Reactive Oxygen Species and Biomedical Science Institute, Core Research Institute (CRI), Kyung Hee University, Seoul, 02447, Republic of Korea.
- Department of Medical Zoology, School of Medicine, Kyung Hee University, Seoul, 02447, Republic of Korea.
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4
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Langedijk AC, Bont LJ. Respiratory syncytial virus infection and novel interventions. Nat Rev Microbiol 2023; 21:734-749. [PMID: 37438492 DOI: 10.1038/s41579-023-00919-w] [Citation(s) in RCA: 37] [Impact Index Per Article: 37.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/17/2023] [Indexed: 07/14/2023]
Abstract
The large global burden of respiratory syncytial virus (RSV) respiratory tract infections in young children and older adults has gained increased recognition in recent years. Recent discoveries regarding the neutralization-specific viral epitopes of the pre-fusion RSV glycoprotein have led to a shift from empirical to structure-based design of RSV therapeutics, and controlled human infection model studies have provided early-stage proof of concept for novel RSV monoclonal antibodies, vaccines and antiviral drugs. The world's first vaccines and first monoclonal antibody to prevent RSV among older adults and all infants, respectively, have recently been approved. Large-scale introduction of RSV prophylactics emphasizes the need for active surveillance to understand the global impact of these interventions over time and to timely identify viral mutants that are able to escape novel prophylactics. In this Review, we provide an overview of RSV interventions in clinical development, highlighting global disease burden, seasonality, pathogenesis, and host and viral factors related to RSV immunity.
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Affiliation(s)
- Annefleur C Langedijk
- Department of Paediatric Immunology and Infectious Diseases, Wilhelmina Children's Hospital, University Medical Centre Utrecht, Utrecht, the Netherlands
| | - Louis J Bont
- Department of Paediatric Immunology and Infectious Diseases, Wilhelmina Children's Hospital, University Medical Centre Utrecht, Utrecht, the Netherlands.
- ReSViNET Foundation, Zeist, the Netherlands.
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5
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Cadena-Cruz C, Villarreal Camacho JL, De Ávila-Arias M, Hurtado-Gomez L, Rodriguez A, San-Juan-Vergara H. Respiratory syncytial virus entry mechanism in host cells: A general overview. Mol Microbiol 2023; 120:341-350. [PMID: 37537859 DOI: 10.1111/mmi.15133] [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: 04/10/2023] [Revised: 07/05/2023] [Accepted: 07/12/2023] [Indexed: 08/05/2023]
Abstract
Respiratory syncytial virus (RSV) is a virus that causes acute respiratory infections in neonates and older adults. To infect host cells, the attachment glycoprotein (G) interacts with a cell surface receptor. This interaction determines the specific cell types that are susceptible to infection. RSV possesses a type I fusion protein F. Type I fusion proteins are metastable when rearrangement of the prefusion F occurs; the fusion peptide is exposed transforming the protein into postfusion form. The transition between the prefusion form and its postfusion form facilitates the viral envelope and the host cell membrane to fuse, enabling the virus to enter the host cell. Understanding the entry mechanism employed by RSV is crucial for developing effective antiviral therapies. In this review, we will discuss the various types of viral fusion proteins and explore the potential entry mechanisms utilized by RSV. A deeper understanding of these mechanisms will provide valuable insights for the development of novel approaches to treat RSV infections.
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Affiliation(s)
- C Cadena-Cruz
- División Ciencias de la Salud, Universidad del Norte Barranquilla, Barranquilla, Colombia
- Facultad de Ciencias de la Salud, Programa de Medicina, Universidad Libre Seccional Barranquilla, Barranquilla, Colombia
| | - J L Villarreal Camacho
- Facultad de Ciencias de la Salud, Programa de Medicina, Universidad Libre Seccional Barranquilla, Barranquilla, Colombia
| | - Marcio De Ávila-Arias
- División Ciencias de la Salud, Universidad del Norte Barranquilla, Barranquilla, Colombia
| | - Leidy Hurtado-Gomez
- División Ciencias de la Salud, Universidad del Norte Barranquilla, Barranquilla, Colombia
| | - Alexander Rodriguez
- División Ciencias de la Salud, Universidad del Norte Barranquilla, Barranquilla, Colombia
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Lara-Hernandez I, Muñoz-Escalante JC, Bernal-Silva S, Noyola DE, Wong-Chew RM, Comas-García A, Comas-Garcia M. Ultrastructural and Functional Characterization of Mitochondrial Dynamics Induced by Human Respiratory Syncytial Virus Infection in HEp-2 Cells. Viruses 2023; 15:1518. [PMID: 37515204 PMCID: PMC10386036 DOI: 10.3390/v15071518] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2023] [Revised: 06/27/2023] [Accepted: 07/05/2023] [Indexed: 07/30/2023] Open
Abstract
Human respiratory syncytial virus (hRSV) is the leading cause of acute lower respiratory tract infections in children under five years of age and older adults worldwide. During hRSV infection, host cells undergo changes in endomembrane organelles, including mitochondria. This organelle is responsible for energy production in the cell and plays an important role in the antiviral response. The present study focuses on characterizing the ultrastructural and functional changes during hRSV infection using thin-section transmission electron microscopy and RT-qPCR. Here we report that hRSV infection alters mitochondrial morphodynamics by regulating the expression of key genes in the antiviral response process, such as Mfn1, VDAC2, and PINK1. Our results suggest that hRSV alters mitochondrial morphology during infection, producing a mitochondrial phenotype with shortened cristae, swollen matrix, and damaged membrane. We also observed that hRSV infection modulates the expression of the aforementioned genes, possibly as an evasion mechanism in the face of cellular antiviral response. Taken together, these results advance our knowledge of the ultrastructural alterations associated with hRSV infection and might guide future therapeutic efforts to develop effective antiviral drugs for hRSV treatment.
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Affiliation(s)
- Ignacio Lara-Hernandez
- High-Resolution Microscopy Section, Center for Research in Health Sciences and Biomedicine, Autonomous University of San Luis Potosí, San Luis Potosí 78210, Mexico
| | - Juan Carlos Muñoz-Escalante
- Center for Research in Health Sciences and Biomedicine, Autonomous University of San Luis Potosí, San Luis Potosí 78210, Mexico
- Department of Microbiology, School of Medicine, Autonomous University of San Luis Potosí, San Luis Potosí 78210, Mexico
| | - Sofía Bernal-Silva
- Department of Microbiology, School of Medicine, Autonomous University of San Luis Potosí, San Luis Potosí 78210, Mexico
- Genomic Medicine Section, Center for Research in Health Sciences and Biomedicine, Autonomous University of San Luis Potosí, San Luis Potosí 78210, Mexico
| | - Daniel E Noyola
- Center for Research in Health Sciences and Biomedicine, Autonomous University of San Luis Potosí, San Luis Potosí 78210, Mexico
- Department of Microbiology, School of Medicine, Autonomous University of San Luis Potosí, San Luis Potosí 78210, Mexico
| | - Rosa María Wong-Chew
- Research Division, School of Medicine, National Autonomous University of Mexico, Mexico City 04360, Mexico
| | - Andreu Comas-García
- Department of Microbiology, School of Medicine, Autonomous University of San Luis Potosí, San Luis Potosí 78210, Mexico
| | - Mauricio Comas-Garcia
- High-Resolution Microscopy Section, Center for Research in Health Sciences and Biomedicine, Autonomous University of San Luis Potosí, San Luis Potosí 78210, Mexico
- Science Department, Autonomous University of San Luis Potosí, San Luis Potosí 78210, Mexico
- Molecular and Translation Medicine Section, Center for Research in Health Sciences and Biomedicine, Autonomous University of San Luis Potosí, San Luis Potosí 78210, Mexico
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Abstract
PURPOSE OF REVIEW Respiratory syncytial virus (RSV) continues to be a major cause of severe lower respiratory tract infection in infants, young children, and older adults. In this review, changes in the epidemiology of RSV during the coronavirus disease 2019 (COVID-19) pandemic are highlighted together with the role which increased molecular surveillance efforts will have in future in assessing the efficacy of vaccines and therapeutics. RECENT FINDINGS The introduction of nonpharmaceutical intervention (NPIs) strategies during the COVID-19 pandemic between 2020 and 2022 resulted in worldwide disruption to the epidemiology of RSV infections, especially with respect to the timing and peak case rate of annual epidemics. Increased use of whole genome sequencing along with efforts to better standardize the nomenclature of RSV strains and discrimination of RSV genotypes will support increased monitoring of relevant antigenic sites in the viral glycoproteins. Several RSV vaccine candidates based on subunit, viral vectors, nucleic acid, or live attenuated virus strategies have shown efficacy in Phase 2 or 3 clinical trials with vaccines using RSVpreF protein currently the closest to approval and use in high-risk populations. Finally, the recent approval and future use of the extended half-life human monoclonal antibody Nirsevimab will also help to alleviate the morbidity and mortality burden caused by annual epidemics of RSV infections. SUMMARY The ongoing expansion and wider coordination of RSV molecular surveillance efforts via whole genome sequencing will be crucial for future monitoring of the efficacy of a new generation of vaccines and therapeutics.
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Affiliation(s)
- Martin Ludlow
- Research Center for Emerging Infections and Zoonoses, University of Veterinary Medicine Hannover, Hannover, Germany
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8
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Bergeron HC, Tripp RA. RSV Replication, Transmission, and Disease Are Influenced by the RSV G Protein. Viruses 2022; 14:v14112396. [PMID: 36366494 PMCID: PMC9692685 DOI: 10.3390/v14112396] [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: 09/26/2022] [Revised: 10/24/2022] [Accepted: 10/28/2022] [Indexed: 01/31/2023] Open
Abstract
It is important to understand the features affecting virus replication, fitness, and transmissibility as they contribute to the outcome of infection and affect disease intervention approaches. Respiratory syncytial virus (RSV) is a major contributor to respiratory disease, particularly in the infant and elderly populations. Although first described over 60 years ago, there are no approved vaccines and there are limited specific antiviral treatments due in part to our incomplete understanding of the features affecting RSV replication, immunity, and disease. RSV studies have typically focused on using continuous cell lines and conventional RSV strains to establish vaccine development and various antiviral countermeasures. This review outlines how the RSV G protein influences viral features, including replication, transmission, and disease, and how understanding the role of the G protein can improve the understanding of preclinical studies.
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Roe MK, Perez MA, Hsiao HM, Lapp SA, Sun HY, Jadhao S, Young AR, Batista YS, Reed RC, Taz A, Piantadosi A, Chen X, Liang B, Koval M, Snider TA, Moore ML, Anderson EJ, Anderson LJ, Stobart CC, Rostad CA. An RSV Live-Attenuated Vaccine Candidate Lacking G Protein Mucin Domains Is Attenuated, Immunogenic, and Effective in Preventing RSV in BALB/c Mice. J Infect Dis 2022; 227:50-60. [PMID: 36281651 PMCID: PMC9796166 DOI: 10.1093/infdis/jiac382] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2022] [Revised: 09/09/2022] [Accepted: 10/31/2022] [Indexed: 01/19/2023] Open
Abstract
BACKGROUND Respiratory syncytial virus (RSV) is a leading viral respiratory pathogen in infants. The objective of this study was to generate RSV live-attenuated vaccine (LAV) candidates by removing the G-protein mucin domains to attenuate viral replication while retaining immunogenicity through deshielding of surface epitopes. METHODS Two LAV candidates were generated from recombinant RSV A2-line19F by deletion of the G-protein mucin domains (A2-line19F-G155) or deletion of the G-protein mucin and transmembrane domains (A2-line19F-G155S). Vaccine attenuation was measured in BALB/c mouse lungs by fluorescent focus unit (FFU) assays and real-time polymerase chain reaction (RT-PCR). Immunogenicity was determined by measuring serum binding and neutralizing antibodies in mice following prime/boost on days 28 and 59. Efficacy was determined by measuring RSV lung viral loads on day 4 postchallenge. RESULTS Both LAVs were undetectable in mouse lungs by FFU assay and elicited similar neutralizing antibody titers compared to A2-line19F on days 28 and 59. Following RSV challenge, vaccinated mice showed no detectable RSV in the lungs by FFU assay and a significant reduction in RSV RNA in the lungs by RT-PCR of 560-fold for A2-line19F-G155 and 604-fold for A2-line19F-G155S compared to RSV-challenged, unvaccinated mice. CONCLUSIONS Removal of the G-protein mucin domains produced RSV LAV candidates that were highly attenuated with retained immunogenicity.
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Affiliation(s)
- Molly K Roe
- Department of Biological Sciences, Butler University, Indianapolis, Indiana, USA
| | - Maria A Perez
- Department of Pediatrics, Emory University School of Medicine, Atlanta, Georgia, USA,Center for Childhood Infections and Vaccines, Children's Healthcare of Atlanta and Emory University School of Medicine, Atlanta, Georgia, USA
| | - Hui-Mien Hsiao
- Department of Pediatrics, Emory University School of Medicine, Atlanta, Georgia, USA,Center for Childhood Infections and Vaccines, Children's Healthcare of Atlanta and Emory University School of Medicine, Atlanta, Georgia, USA
| | - Stacey A Lapp
- Department of Pediatrics, Emory University School of Medicine, Atlanta, Georgia, USA,Center for Childhood Infections and Vaccines, Children's Healthcare of Atlanta and Emory University School of Medicine, Atlanta, Georgia, USA
| | - He-Ying Sun
- Department of Pediatrics, Emory University School of Medicine, Atlanta, Georgia, USA,Center for Childhood Infections and Vaccines, Children's Healthcare of Atlanta and Emory University School of Medicine, Atlanta, Georgia, USA
| | - Samadhan Jadhao
- Department of Pediatrics, Emory University School of Medicine, Atlanta, Georgia, USA,Center for Childhood Infections and Vaccines, Children's Healthcare of Atlanta and Emory University School of Medicine, Atlanta, Georgia, USA
| | - Audrey R Young
- Department of Biological Sciences, Butler University, Indianapolis, Indiana, USA
| | - Yara S Batista
- Department of Biological Sciences, Butler University, Indianapolis, Indiana, USA
| | - Ryan C Reed
- Department of Medicine, Emory University School of Medicine, Atlanta, Georgia, USA
| | - Azmain Taz
- Department of Medicine, Emory University School of Medicine, Atlanta, Georgia, USA
| | - Anne Piantadosi
- Department of Medicine, Emory University School of Medicine, Atlanta, Georgia, USA
| | - Xuemin Chen
- Department of Pediatrics, Emory University School of Medicine, Atlanta, Georgia, USA,Center for Childhood Infections and Vaccines, Children's Healthcare of Atlanta and Emory University School of Medicine, Atlanta, Georgia, USA
| | - Bo Liang
- Department of Biochemistry, Emory University School of Medicine, Atlanta, Georgia, USA
| | - Michael Koval
- Department of Medicine, Emory University School of Medicine, Atlanta, Georgia, USA
| | - Timothy A Snider
- Department of Veterinary Pathobiology, Oklahoma State University, Stillwater, Oklahoma, USA
| | | | - Evan J Anderson
- Department of Pediatrics, Emory University School of Medicine, Atlanta, Georgia, USA,Center for Childhood Infections and Vaccines, Children's Healthcare of Atlanta and Emory University School of Medicine, Atlanta, Georgia, USA,Department of Medicine, Emory University School of Medicine, Atlanta, Georgia, USA
| | - Larry J Anderson
- Department of Pediatrics, Emory University School of Medicine, Atlanta, Georgia, USA,Center for Childhood Infections and Vaccines, Children's Healthcare of Atlanta and Emory University School of Medicine, Atlanta, Georgia, USA
| | | | - Christina A Rostad
- Correspondence: Christina A. Rostad, MD, Emory Children's Center, 2015 Uppergate Drive NE, Atlanta, GA 30322 ()
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10
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Brakel KA, Ma Y, Binjawadagi R, Harder O, Watts M, Li J, Binjawadagi B, Niewiesk S. Codon-optimization of the respiratory syncytial virus (RSV) G protein expressed in a vesicular stomatitis virus (VSV) vector improves immune responses in a cotton rat model. Virology 2022; 575:101-110. [PMID: 36096069 DOI: 10.1016/j.virol.2022.08.017] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2022] [Revised: 08/17/2022] [Accepted: 08/31/2022] [Indexed: 10/14/2022]
Abstract
Respiratory syncytial virus is an important cause of pneumonia in children, the elderly, and immunocompromised individuals. The attachment (G) protein of RSV generates neutralizing antibodies in natural RSV infection which correlate with protection against disease. The immune response to RSV is typically short-lived, which may be related to the heavy glycosylation of RSV-G. In order to improve its immunogenicity, we expressed G protein mutants in a vesicular stomatitis virus (VSV) vector system and tested their ability to protect cotton rats from RSV challenge. We found that the most protective construct was codon-optimized RSV-G, followed by wild-type G and membrane-bound G. Constructs which expressed the G protein with reduced glycosylation or the secreted G protein provided either partial or no protection. Our results demonstrate that modifications to the G protein are not advantageous in a VSV vector system, and that an intact, codon-optimized G is a superior vaccine candidate.
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Affiliation(s)
- Kelsey A Brakel
- Department of Veterinary Biosciences, College of Veterinary Medicine, The Ohio State University, Columbus, OH, United States
| | - Yuanmei Ma
- Department of Veterinary Biosciences, College of Veterinary Medicine, The Ohio State University, Columbus, OH, United States
| | - Rashmi Binjawadagi
- Department of Veterinary Biosciences, College of Veterinary Medicine, The Ohio State University, Columbus, OH, United States
| | - Olivia Harder
- Department of Veterinary Biosciences, College of Veterinary Medicine, The Ohio State University, Columbus, OH, United States
| | - Mauria Watts
- Department of Veterinary Clinical Sciences, College of Veterinary Medicine, The Ohio State University, Columbus, OH, United States
| | - Jianrong Li
- Department of Veterinary Biosciences, College of Veterinary Medicine, The Ohio State University, Columbus, OH, United States
| | - Basavaraj Binjawadagi
- Department of Veterinary Biosciences, College of Veterinary Medicine, The Ohio State University, Columbus, OH, United States; Ceva Sante Animale, Lenexa, KS, United States
| | - Stefan Niewiesk
- Department of Veterinary Biosciences, College of Veterinary Medicine, The Ohio State University, Columbus, OH, United States.
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11
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Baraldi E, Checcucci Lisi G, Costantino C, Heinrichs JH, Manzoni P, Riccò M, Roberts M, Vassilouthis N. RSV disease in infants and young children: Can we see a brighter future? Hum Vaccin Immunother 2022; 18:2079322. [PMID: 35724340 DOI: 10.1080/21645515.2022.2079322] [Citation(s) in RCA: 22] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
Respiratory syncytial virus (RSV) is a highly contagious seasonal virus and the leading cause of Lower Respiratory Tract Infections (LRTI), including pneumonia and bronchiolitis in children. RSV-related LRTI cause approximately 3 million hospitalizations and 120,000 deaths annually among children <5 years of age. The majority of the burden of RSV occurs in previously healthy infants. Only a monoclonal antibody (mAb) has been approved against RSV infections in a restricted group, leaving an urgent unmet need for a large number of children potentially benefiting from preventive measures. Approaches under development include maternal vaccines to protect newborns, extended half-life monoclonal antibodies to provide rapid long-lasting protection, and pediatric vaccines. RSV has been identified as a major global priority but a solution to tackle this unmet need for all children has yet to be implemented. New technologies represent the avenue for effectively addressing the leading-cause of hospitalization in children <1 years old.
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Affiliation(s)
- Eugenio Baraldi
- Department of Women's and Children's Health, University Hospital of Padova, Padova, Italy
| | | | - Claudio Costantino
- Department of Health Promotion Sciences, Maternal and Infant Care, Internal Medicine and Medical Specialties (PROMISE) "G. D'Alessandro", University of Palermo, Palermo, Italy
| | | | - Paolo Manzoni
- Department of Pediatrics and Neonatology, University Hospital Degli Infermi, Biella, Italy
| | - Matteo Riccò
- Dipartimento di Sanità Pubblica, Servizio di Prevenzione e Sicurezza Negli Ambienti di Lavoro (SPSAL), AUSL-IRCCS di Reggio Emilia, Reggio Emilia, Italy
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12
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Xu Q, Li L, Shen L, Huang X, Lu M, Hu C. Development and external validation of a simple nomogram for predicting apnea in children hospitalized with bronchiolitis. Front Pediatr 2022; 10:922226. [PMID: 36340712 PMCID: PMC9627176 DOI: 10.3389/fped.2022.922226] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/19/2022] [Accepted: 09/23/2022] [Indexed: 11/26/2022] Open
Abstract
BACKGROUND Apnea is one of the most life-threatening complications of bronchiolitis in children. This study aimed to determine early predictors of apnea in children hospitalized with bronchiolitis and develop a simple nomogram to identify patients at risk of apnea. METHODS This retrospective, observational study included children hospitalized with bronchiolitis in two hospitals in China. Demographic and clinical characteristics, laboratory results, pathogens, and pulmonary iconography results were recorded. A training cohort of 759 patients (one hospital) was used to identify early predictors of apnea during hospitalization. The least absolute shrinkage and selection operator (LASSO) regression analysis method was used to optimize variable selection. The nomogram was developed visually based on the variables selected by multivariable logistic regression analysis. Discrimination (concordance index, C-index), calibration, and decision curve analysis (DCA) were used to assess the model performance and clinical effectiveness. RESULTS A total of 1,372 children hospitalized with bronchiolitis were retrospectively evaluated, 133 (9.69%) of whom had apnea. Apnea was observed in 80 of the 759 patients with bronchiolitis in the training cohort and 53 of the 613 patients in the external validation cohort. Underlying diseases, feeding difficulties, tachypnea, retractions and pulmonary atelectasis in the training cohort were independent risk factors for apnea and were assembled into the nomogram. The nomogram exhibited good discrimination with a C-index of 0.883 (95% CI: 0.839-0.927) and good calibration. The DCA showed that the nomogram was clinically useful in estimating the net benefit to patients. CONCLUSION We developed a nomogram that is convenient to use and able to identify the individualized prediction of apnea risk in patients with bronchiolitis. These patients might benefit from early triage and more intensive monitoring.
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Affiliation(s)
- Qiuyan Xu
- Department of Pediatrics, Suzhou Science / Technology Town Hospital, Suzhou, China
| | - Linlin Li
- Department of Respiratory Medicine, Children's Hospital of Nanjing Medical University, Nanjing, China
| | - Li Shen
- Department of Pharmacy, Suzhou Science / Technology Town Hospital, Suzhou, China
| | - Xia Huang
- Department of Respiratory Medicine, Children's Hospital of Nanjing Medical University, Nanjing, China
| | - Min Lu
- Department of Pediatrics, Suzhou Science / Technology Town Hospital, Suzhou, China
| | - Chunxia Hu
- Department of Respiratory Medicine, Children's Hospital of Wujiang District, Children's Hospital of Soochow University, Suzhou, China
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Mallampalli RK, Adair J, Elhance A, Farkas D, Chafin L, Long ME, De M, Mora AL, Rojas M, Peters V, Bednash JS, Tsai M, Londino JD. Interferon Lambda Signaling in Macrophages Is Necessary for the Antiviral Response to Influenza. Front Immunol 2021; 12:735576. [PMID: 34899695 PMCID: PMC8655102 DOI: 10.3389/fimmu.2021.735576] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2021] [Accepted: 11/04/2021] [Indexed: 01/14/2023] Open
Abstract
Interferon lambda (IFNλ) signaling is a promising therapeutic target against viral infection in murine models, yet little is known about its molecular regulation and its cognate receptor, interferon lambda receptor 1 (IFNLR1) in human lung. We hypothesized that the IFNλ signaling axis was active in human lung macrophages. In human alveolar macrophages (HAMs), we observed increased IFNLR1 expression and robust increase in interferon-stimulated gene (ISG) expression in response to IFNλ ligand. While human monocytes express minimal IFNLR1, differentiation of monocytes into macrophages with macrophage colony-stimulating factor (M-CSF) or granulocyte-macrophage colony-stimulating factor (GM-CSF) increased IFNLR1 mRNA, IFNLR1 protein expression, and cellular response to IFNλ ligation. Conversely, in mice, M-CSF or GM-CSF stimulated macrophages failed to produce ISGs in response to related ligands, IFNL2 or IFNL3, suggesting that IFNLR1 signaling in macrophages is species-specific. We next hypothesized that IFNλ signaling was critical in influenza antiviral responses. In primary human airway epithelial cells and precision-cut human lung slices, influenza infection substantially increased IFNλ levels. Pretreatment of both HAMs and differentiated human monocytes with IFNL1 significantly inhibited influenza infection. IFNLR1 knockout in the myeloid cell line, THP-1, exhibited reduced interferon responses to either direct or indirect exposure to influenza infection suggesting the indispensability of IFNLR1 for antiviral responses. These data demonstrate the presence of IFNλ - IFNLR1 signaling axis in human lung macrophages and a critical role of IFNλ signaling in combating influenza infection.
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Affiliation(s)
- Rama K. Mallampalli
- Department of Internal Medicine, Division of Pulmonary, Critical Care, and Sleep Medicine, Davis Heart and Lung Research Institute, Columbus, Ohio, United States
| | - Jessica Adair
- Department of Internal Medicine, Division of Pulmonary, Critical Care, and Sleep Medicine, Davis Heart and Lung Research Institute, Columbus, Ohio, United States
| | - Ajit Elhance
- Department of Internal Medicine, Division of Pulmonary, Critical Care, and Sleep Medicine, Davis Heart and Lung Research Institute, Columbus, Ohio, United States
| | - Daniela Farkas
- Department of Internal Medicine, Division of Pulmonary, Critical Care, and Sleep Medicine, Davis Heart and Lung Research Institute, Columbus, Ohio, United States
| | - Lexie Chafin
- Department of Internal Medicine, Division of Pulmonary, Critical Care, and Sleep Medicine, Davis Heart and Lung Research Institute, Columbus, Ohio, United States
| | - Matthew E. Long
- Department of Internal Medicine, Division of Pulmonary, Critical Care, and Sleep Medicine, Davis Heart and Lung Research Institute, Columbus, Ohio, United States,Department of Microbial Infection and Immunity, The Ohio State University Wexner Medical Center, Columbus, Ohio, United States
| | - Mithu De
- Department of Internal Medicine, Division of Pulmonary, Critical Care, and Sleep Medicine, Davis Heart and Lung Research Institute, Columbus, Ohio, United States
| | - Ana L. Mora
- Department of Internal Medicine, Division of Pulmonary, Critical Care, and Sleep Medicine, Davis Heart and Lung Research Institute, Columbus, Ohio, United States
| | - Mauricio Rojas
- Department of Internal Medicine, Division of Pulmonary, Critical Care, and Sleep Medicine, Davis Heart and Lung Research Institute, Columbus, Ohio, United States
| | - Victor Peters
- Department of Internal Medicine, Division of Pulmonary, Critical Care, and Sleep Medicine, Davis Heart and Lung Research Institute, Columbus, Ohio, United States
| | - Joseph S. Bednash
- Department of Internal Medicine, Division of Pulmonary, Critical Care, and Sleep Medicine, Davis Heart and Lung Research Institute, Columbus, Ohio, United States
| | - MuChun Tsai
- Department of Internal Medicine, Division of Pulmonary, Critical Care, and Sleep Medicine, Davis Heart and Lung Research Institute, Columbus, Ohio, United States
| | - James D. Londino
- Department of Internal Medicine, Division of Pulmonary, Critical Care, and Sleep Medicine, Davis Heart and Lung Research Institute, Columbus, Ohio, United States,*Correspondence: James D. Londino,
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Brakel KA, Binjawadagi B, French-Kim K, Watts M, Harder O, Ma Y, Li J, Niewiesk S. Coexpression of respiratory syncytial virus (RSV) fusion (F) protein and attachment glycoprotein (G) in a vesicular stomatitis virus (VSV) vector system provides synergistic effects against RSV infection in a cotton rat model. Vaccine 2021; 39:6817-6828. [PMID: 34702618 PMCID: PMC8595748 DOI: 10.1016/j.vaccine.2021.10.042] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2021] [Revised: 10/11/2021] [Accepted: 10/19/2021] [Indexed: 11/20/2022]
Abstract
Respiratory syncytial virus (RSV) is one of the most important causes of respiratory disease in infants, immunocompromised individuals, and the elderly. Natural infection does not result in long-term immunity, and there is no licensed vaccine. Vesicular stomatitis virus (VSV) is a commonly used vaccine vector platform against infectious diseases, and has been used as a vector for a licensed Ebola vaccine. In this study, we expressed the RSV fusion (F) protein, the RSV F protein stabilized in either a pre-fusion or a post-fusion configuration, the attachment glycoprotein (G), or the G and F proteins of RSV in combination in a VSV vector. Cotton rats were immunized with these recombinants intranasally or subcutaneously to test immunogenicity. RSV F stabilized in either a pre-fusion or a post-fusion configuration proved to be poorly immunogenic and protective when compared to unmodified F. RSV G provided partial protection and moderate levels of neutralizing antibody production, both of which improved with intranasal administration compared to subcutaneous inoculation. The most successful vaccine vector was VSV expressing both the G and F proteins after intranasal inoculation. Immunization with this recombinant induced neutralizing antibodies and provided protection from RSV challenge in the upper and lower respiratory tract for at least 80 days. Our results demonstrate that co-expression of F and G proteins in a VSV vector provides synergistic effects in inducing RSV-specific neutralizing antibodies and protection against RSV infection.
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Affiliation(s)
- Kelsey A Brakel
- Department of Veterinary Biosciences, College of Veterinary Medicine, The Ohio State University, Columbus, OH, United States.
| | - Basavaraj Binjawadagi
- Department of Veterinary Biosciences, College of Veterinary Medicine, The Ohio State University, Columbus, OH, United States; Ceva Sante Animale, Lenexa, KS, United States
| | - Kristen French-Kim
- Department of Veterinary Biosciences, College of Veterinary Medicine, The Ohio State University, Columbus, OH, United States
| | - Mauria Watts
- Department of Veterinary Clinical Sciences, College of Veterinary Medicine, The Ohio State University, Columbus, OH, United States
| | - Olivia Harder
- Department of Veterinary Biosciences, College of Veterinary Medicine, The Ohio State University, Columbus, OH, United States
| | - Yuanmei Ma
- Department of Veterinary Biosciences, College of Veterinary Medicine, The Ohio State University, Columbus, OH, United States
| | - Jianrong Li
- Department of Veterinary Biosciences, College of Veterinary Medicine, The Ohio State University, Columbus, OH, United States
| | - Stefan Niewiesk
- Department of Veterinary Biosciences, College of Veterinary Medicine, The Ohio State University, Columbus, OH, United States
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Shang Z, Tan S, Ma D. Respiratory syncytial virus: from pathogenesis to potential therapeutic strategies. Int J Biol Sci 2021; 17:4073-4091. [PMID: 34671221 PMCID: PMC8495404 DOI: 10.7150/ijbs.64762] [Citation(s) in RCA: 29] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2021] [Accepted: 09/18/2021] [Indexed: 01/23/2023] Open
Abstract
Respiratory syncytial virus (RSV) is one of the most important viral pathogens causing respiratory tract infection in infants, the elderly and people with poor immune function, which causes a huge disease burden worldwide every year. It has been more than 60 years since RSV was discovered, and the palivizumab monoclonal antibody, the only approved specific treatment, is limited to use for passive immunoprophylaxis in high-risk infants; no other intervention has been approved to date. However, in the past decade, substantial progress has been made in characterizing the structure and function of RSV components, their interactions with host surface molecules, and the host innate and adaptive immune response to infection. In addition, basic and important findings have also piqued widespread interest among researchers and pharmaceutical companies searching for effective interventions for RSV infection. A large number of promising monoclonal antibodies and inhibitors have been screened, and new vaccine candidates have been designed for clinical evaluation. In this review, we first briefly introduce the structural composition, host cell surface receptors and life cycle of RSV virions. Then, we discuss the latest findings related to the pathogenesis of RSV. We also focus on the latest clinical progress in the prevention and treatment of RSV infection through the development of monoclonal antibodies, vaccines and small-molecule inhibitors. Finally, we look forward to the prospects and challenges of future RSV research and clinical intervention.
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Affiliation(s)
- Zifang Shang
- Institute of Pediatrics, Shenzhen Children's Hospital, 518026 Shenzhen, Guangdong Province, China.,CAS Key Laboratory of Pathogenic Microbiology and Immunology, Institute of Microbiology, Chinese Academy of Sciences, 100101Beijing, China
| | - Shuguang Tan
- CAS Key Laboratory of Pathogenic Microbiology and Immunology, Institute of Microbiology, Chinese Academy of Sciences, 100101Beijing, China
| | - Dongli Ma
- Institute of Pediatrics, Shenzhen Children's Hospital, 518026 Shenzhen, Guangdong Province, China
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Anderson LJ, Jadhao SJ, Paden CR, Tong S. Functional Features of the Respiratory Syncytial Virus G Protein. Viruses 2021; 13:1214. [PMID: 34372490 PMCID: PMC8310105 DOI: 10.3390/v13071214] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2021] [Revised: 05/28/2021] [Accepted: 06/18/2021] [Indexed: 12/20/2022] Open
Abstract
Respiratory syncytial virus (RSV) is a major cause of serious lower respiratory tract infections in children <5 years of age worldwide and repeated infections throughout life leading to serious disease in the elderly and persons with compromised immune, cardiac, and pulmonary systems. The disease burden has made it a high priority for vaccine and antiviral drug development but without success except for immune prophylaxis for certain young infants. Two RSV proteins are associated with protection, F and G, and F is most often pursued for vaccine and antiviral drug development. Several features of the G protein suggest it could also be an important to vaccine or antiviral drug target design. We review features of G that effect biology of infection, the host immune response, and disease associated with infection. Though it is not clear how to fit these together into an integrated picture, it is clear that G mediates cell surface binding and facilitates cellular infection, modulates host responses that affect both immunity and disease, and its CX3C aa motif contributes to many of these effects. These features of G and the ability to block the effects with antibody, suggest G has substantial potential in vaccine and antiviral drug design.
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Affiliation(s)
- Larry J. Anderson
- Department of Pediatrics, Emory University School of Medicine and Children’s Healthcare of Atlanta, Atlanta, GA 30322, USA;
| | - Samadhan J. Jadhao
- Department of Pediatrics, Emory University School of Medicine and Children’s Healthcare of Atlanta, Atlanta, GA 30322, USA;
| | - Clinton R. Paden
- Division of Viral Diseases, National Center for Immunization and Respiratory Diseases, Centers for Disease Control and Prevention, Atlanta, GA 30322, USA; (C.R.P.); (S.T.)
| | - Suxiang Tong
- Division of Viral Diseases, National Center for Immunization and Respiratory Diseases, Centers for Disease Control and Prevention, Atlanta, GA 30322, USA; (C.R.P.); (S.T.)
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