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Loaiza RA, Ramírez RA, Sepúlveda-Alfaro J, Ramírez MA, Andrade CA, Soto JA, González PA, Bueno SM, Kalergis AM. A molecular perspective for the development of antibodies against the human respiratory syncytial virus. Antiviral Res 2024; 222:105783. [PMID: 38145755 DOI: 10.1016/j.antiviral.2023.105783] [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: 10/07/2023] [Revised: 12/11/2023] [Accepted: 12/12/2023] [Indexed: 12/27/2023]
Abstract
The human respiratory syncytial virus (hRSV) is the leading etiologic agent causing respiratory infections in infants, children, older adults, and patients with comorbidities. Sixty-seven years have passed since the discovery of hRSV, and only a few successful mitigation or treatment tools have been developed against this virus. One of these is immunotherapy with monoclonal antibodies against structural proteins of the virus, such as Palivizumab, the first prophylactic approach approved by the Food and Drug Administration (FDA) of the USA. In this article, we discuss different strategies for the prevention and treatment of hRSV infection, focusing on the molecular mechanisms against each target that underly the rational design of antibodies against hRSV. At the same time, we describe the latest results regarding currently approved therapies against hRSV and the challenges associated with developing new candidates.
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Affiliation(s)
- Ricardo A Loaiza
- Millennium Institute on Immunology and Immunotherapy, Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Chile
| | - Robinson A Ramírez
- Millennium Institute on Immunology and Immunotherapy, Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Chile
| | - Javiera Sepúlveda-Alfaro
- Millennium Institute on Immunology and Immunotherapy, Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Chile
| | - Mario A Ramírez
- Millennium Institute on Immunology and Immunotherapy, Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Chile
| | - Catalina A Andrade
- Millennium Institute on Immunology and Immunotherapy, Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Chile
| | - Jorge A Soto
- Millennium Institute on Immunology and Immunotherapy, Departamento de Ciencias Biológicas, Facultad de Ciencias de La Vida, Universidad Andrés Bello, Santiago, Chile
| | - Pablo A González
- Millennium Institute on Immunology and Immunotherapy, Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Chile
| | - Susan M Bueno
- Millennium Institute on Immunology and Immunotherapy, Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Chile
| | - Alexis M Kalergis
- Millennium Institute on Immunology and Immunotherapy, Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Chile; Departamento de Endocrinología, Facultad de Medicina, Pontificia Universidad Católica de Chile, Chile.
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2
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da Silva RP, Thomé BL, da Souza APD. Exploring the Immune Response against RSV and SARS-CoV-2 Infection in Children. BIOLOGY 2023; 12:1223. [PMID: 37759622 PMCID: PMC10525162 DOI: 10.3390/biology12091223] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/10/2023] [Revised: 09/01/2023] [Accepted: 09/06/2023] [Indexed: 09/29/2023]
Abstract
Viral respiratory tract infections are a significant public health concern, particularly in children. RSV is a prominent cause of lower respiratory tract infections among infants, whereas SARS-CoV-2 has caused a global pandemic with lower overall severity in children than in adults. In this review, we aimed to compare the innate and adaptive immune responses induced by RSV and SARS-CoV-2 to better understand differences in the pathogenesis of infection. Some studies have demonstrated that children present a more robust immune response against SARS-CoV-2 than adults; however, this response is dissimilar to that of RSV. Each virus has a distinctive mechanism to escape the immune response. Understanding the mechanisms underlying these differences is crucial for developing effective treatments and improving the management of pediatric respiratory infections.
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Affiliation(s)
| | | | - Ana Paula Duarte da Souza
- Laboratory of Clinical and Experimental Immunology, Pontifical Catholic University of Rio Grande do Sul, Porto Alegre 90619-900, Brazil; (R.P.d.S.); (B.L.T.)
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3
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Singh S, Maheshwari A, Namazova I, Benjamin JT, Wang Y. Respiratory Syncytial Virus Infections in Neonates: A Persisting Problem. NEWBORN (CLARKSVILLE, MD.) 2023; 2:222-234. [PMID: 38348152 PMCID: PMC10860331 DOI: 10.5005/jp-journals-11002-0073] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 02/15/2024]
Abstract
Respiratory syncytial virus (RSV) is the most common cause of lower respiratory tract infections in young infants. It is an enveloped, single-stranded, nonsegmented, negative-strand RNA virus, a member of the family Pneumoviridae. Globally, RSV is responsible for 2.3% of deaths among neonates 0-27 days of age. Respiratory syncytial virus infection is most common in children aged below 24 months. Neonates present with cough and fever. Respiratory syncytial virus-associated wheezing is seen in 20% infants during the first year of life of which 2-3% require hospitalization. Reverse transcriptase polymerase chain reaction (RT-PCR) gives fast results and has higher sensitivity compared with culture and rapid antigen tests and are not affected by passively administered antibody to RSV. Therapy for RSV infection of the LRT is mainly supportive, and preventive measures like good hygiene and isolation are the mainstay of management. Standard precautions, hand hygiene, breastfeeding and contact isolation should be followed for RSV-infected newborns. Recent AAP guidelines do not recommend pavilizumab prophylaxis for preterm infants born at 29-35 weeks without chronic lung disease, hemodynamically significant congenital heart disease and coexisting conditions. RSV can lead to long-term sequelae such as wheezing and asthma, associated with increased healthcare costs and reduced quality of life.
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Affiliation(s)
- Srijan Singh
- Neonatologist, Kailash Hospital, Noida, Uttar Pradesh, India
- Global Newborn Society (https://www.globalnewbornsociety.org/)
| | - Akhil Maheshwari
- Global Newborn Society (https://www.globalnewbornsociety.org/)
- Department of Pediatrics, Louisiana State University, Shreveport, Louisiana, United States of America
| | - Ilhama Namazova
- Global Newborn Society (https://www.globalnewbornsociety.org/)
- Department of Pediatrics, Azerbaijan Tibb Universiteti, Baku, Azerbaijan
| | - John T Benjamin
- Global Newborn Society (https://www.globalnewbornsociety.org/)
- Department of Pediatrics, Vanderbilt University Medical Center, Nashville, Tennessee, United States of America
| | - Yuping Wang
- Department of Obstetrics and Gynaecology, Louisiana State University, Shreveport, Louisiana, United States of America
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4
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Michalaki C, Dean C, Johansson C. The Use of Precision‐Cut Lung Slices for Studying Innate Immunity to Viral Infections. Curr Protoc 2022; 2:e505. [PMID: 35938685 PMCID: PMC9545600 DOI: 10.1002/cpz1.505] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Precision‐cut lung slices (PCLS) are a novel tool to study cells of the lower airways. As PCLS retain the integrity and architecture of the lung, they constitute a robust model for studying the cells of the lower respiratory tract. Use of PCLS for imaging has been previously documented; however, other applications and techniques can also be applied to PCLS to increase their use and therefore decrease the number of animals needed for each experiment. We present a detailed protocol for generating PCLS from the murine lung. We show that cultured PCLS remain viable up to at least 8 days of culture, that RNA can be isolated from the tissue, and that flow cytometry can be carried out on the cells obtained from the PCLS. Furthermore, we demonstrate that cytokines and chemokines can be detected in the culture supernatants of PCLS exposed to viruses. Overall, these protocols expand the use of PCLS, especially for infection studies. © 2022 The Authors. Current Protocols published by Wiley Periodicals LLC. Basic Protocol 1: Precision‐cut lung slices (PCLS) Basic Protocol 2: PCLS culture and viability Basic Protocol 3: RNA isolation from PCLS, cDNA conversion, and RT‐qPCR Basic Protocol 4: Staining of cells from PCLS for flow cytometry Basic Protocol 5: In vivo RSV administration and ex vivo PCLS RSV exposure
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Affiliation(s)
- Christina Michalaki
- Section of Respiratory Infections, National Heart and Lung Institute Imperial College London London United Kingdom
| | - Charlotte Dean
- Cardio Respiratory Interface Section, National Heart and Lung Institute Imperial College London London United Kingdom
| | - Cecilia Johansson
- Section of Respiratory Infections, National Heart and Lung Institute Imperial College London London United Kingdom
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5
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Prediction of the Active Components and Mechanism of Forsythia suspensa Leaf against Respiratory Syncytial Virus Based on Network Pharmacology. EVIDENCE-BASED COMPLEMENTARY AND ALTERNATIVE MEDICINE 2022; 2022:5643345. [PMID: 35911158 PMCID: PMC9328944 DOI: 10.1155/2022/5643345] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/08/2022] [Revised: 05/20/2022] [Accepted: 05/31/2022] [Indexed: 11/18/2022]
Abstract
Objective Forsythia suspensa leaf (FSL) has been used as a health tea in China for centuries. Previous experiments have proved that FSL extract has a good effect on the antirespiratory syncytial virus (RSV) in vitro, but its exact mechanism is not clear. Therefore, this study aims to determine the active components and targets of FSL and further explore its anti-RSV mechanism. Methods UPLC-Q-Exactive-MS was used to analyze the main chemical components of FSL. The compound disease target network, PPI, GO, and KEGG were used to obtain key targets and potential ways. Then, the molecular docking was verified by Schrödinger Maestro software. Next, the cell model of RSV infection was established, and the inhibitory effect of each drug on RSV was detected. Finally, western blotting was used to detect the effect of the active components of FSL on the expression of PI3K/AKT signaling pathway-related protein. Results UPLC-Q-Exactive-MS analysis showed that there were 67 main chemical constituents in FSL, while network pharmacological analysis showed that there were 169 anti-RSV targets of the active components in FSL, involving 177 signal pathways, among which PI3K/AKT signal pathway played an important role in the anti-RSV process of FSL. The results of molecular docking showed that cryptochlorogenic acid, phillyrin, phillygenin, rutin, and rosmarinic acid had higher binding activities to TP53, STAT3, MAPK1, AKT1, and MAPK3, respectively. In vitro experiments showed that phillyrin and rosmarinic acid could effectively improve the survival rate of RSV-infected cells, increase the expression level of PI3K, and decrease the expression level of AKT. Conclusion The active ingredients of FSL, phillyrin, and rosmarinic acid can play an anti-RSV role by inhibiting PI3K/AKT signaling pathway. This study provides reliable theoretical and experimental support for the anti-RSV treatment of FSL.
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Zhang D, Zhao Y, Wang L, You X, Li J, Zhang G, Hou Y, Wang H, He S, Li E. Axl Mediates Resistance to Respiratory Syncytial Virus Infection Independent of Cell Attachment. Am J Respir Cell Mol Biol 2022; 67:227-240. [PMID: 35548971 DOI: 10.1165/rcmb.2021-0362oc] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
Respiratory syncytial virus (RSV) is a leading cause of severe lower respiratory tract infections in infants and young children. Axl, a TAM family receptor tyrosine kinase (RTK), has been demonstrated as a receptor mediating enveloped virus infection. Here we show that Axl functions as a suppressor of antiviral response during RSV infection. Knockdown of Axl expression in human cells resulted in cell resistance to RSV infection although the treatment did not significantly affect RSV binding or cell entry. Mice deficiency of Axl showed resistance to RSV infection including reduction in viral load and in pulmonary injury. Although T lymphocyte and macrophage infiltration was reduced, more IFN-γ producing cells were present in BALF in Axl-/- mice. Less alternatively activated alveolar macrophages were found in the lungs of Axl-/- mice. Axl-/- MEF cells and siRNA-treated human cells had more robust IFN-β and ISG induction of antiviral genes. Furthermore, re-expression of Axl using Ad-mediated Axl delivery repressed ISG induction in Axl-null MEF cells by RSV infection. The results suggest that Axl, independent of being a virus entry receptor of RSV infection, negatively regulates interferon signaling to modulate host antiviral response against RSV infection.
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Affiliation(s)
- Dan Zhang
- State Key Laboratory of Pharmaceutical Biotechnology, 384750, Medical School, Nanjing University, Nanjing, China.,Jiangsu Key Laboratory for Molecular Medicine, 571478, Medical School, Nanjing University, Nanjing, China.,Yancheng Medical Research Center, Medical School, Nanjing University, Nanjing, China
| | - Yuanhui Zhao
- Jiangsu Key Laboratory for Molecular Medicine, 571478, Medical School, Nanjing University, Nanjing, China.,Institute of Medical Virology, Nanjing Drum Tower Hospital, Medical School, Nanjing University, Nanjing, China
| | - Lingling Wang
- State Key Laboratory of Pharmaceutical Biotechnology, 384750, Medical School, Nanjing University, Nanjing, China.,Jiangsu Key Laboratory for Molecular Medicine, 571478, Medical School, Nanjing University, Nanjing, China.,Institute of Medical Virology, Nanjing Drum Tower Hospital, Medical School, Nanjing University, Nanjing, China
| | - Xiaoxin You
- Jiangsu Key Laboratory for Molecular Medicine, 571478, Medical School, Nanjing University, Nanjing, China.,Institute of Medical Virology, Nanjing Drum Tower Hospital, Medical School, Nanjing University, Nanjing, China
| | - Jingjing Li
- State Key Laboratory of Pharmaceutical Biotechnology, 384750, Medical School, Nanjing University, Nanjing, China.,Jiangsu Key Laboratory for Molecular Medicine, 571478, Medical School, Nanjing University, Nanjing, China
| | - Guohai Zhang
- State Key Laboratory of Pharmaceutical Biotechnology, 384750, Medical School, Nanjing University, Nanjing, China.,State Key Laboratory for Chemistry and Molecular Engineering of Medicinal Resources, School of Chemistry and Pharmaceutical Sciences, Guangxi Normal University, Guangxi, China
| | - Yayi Hou
- State Key Laboratory of Pharmaceutical Biotechnology, 384750, Medical School, Nanjing University, Nanjing, China.,Jiangsu Key Laboratory for Molecular Medicine, 571478, Medical School, Nanjing University, Nanjing, China
| | - Hongwei Wang
- Jiangsu Key Laboratory for Molecular Medicine, 571478, Medical School, Nanjing University, Nanjing, China
| | - Susu He
- State Key Laboratory of Pharmaceutical Biotechnology, 384750, Medical School, Nanjing University, Nanjing, China.,Jiangsu Key Laboratory for Molecular Medicine, 571478, Medical School, Nanjing University, Nanjing, China.,Yancheng Medical Research Center, Medical School, Nanjing University, Nanjing, China
| | - Erguang Li
- State Key Laboratory of Pharmaceutical Biotechnology, 384750, Medical School, Nanjing University, Nanjing, China.,Jiangsu Key Laboratory for Molecular Medicine, 571478, Medical School, Nanjing University, Nanjing, China.,Institute of Medical Virology, Nanjing Drum Tower Hospital, Medical School, Nanjing University, Nanjing, China.,Shenzhen Research Institute, Nanjing University, Nanjing, China;
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7
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Varese A, Nakawesi J, Farias A, Kirsebom FCM, Paulsen M, Nuriev R, Johansson C. Type I interferons and MAVS signaling are necessary for tissue resident memory CD8+ T cell responses to RSV infection. PLoS Pathog 2022; 18:e1010272. [PMID: 35108347 PMCID: PMC8843175 DOI: 10.1371/journal.ppat.1010272] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2021] [Revised: 02/14/2022] [Accepted: 01/12/2022] [Indexed: 01/15/2023] Open
Abstract
Respiratory syncytial virus (RSV) can cause bronchiolitis and viral pneumonia in young children and the elderly. Lack of vaccines and recurrence of RSV infection indicate the difficulty in eliciting protective memory immune responses. Tissue resident memory T cells (TRM) can confer protection from pathogen re-infection and, in human experimental RSV infection, the presence of lung CD8+ TRM cells correlates with a better outcome. However, the requirements for generating and maintaining lung TRM cells during RSV infection are not fully understood. Here, we use mouse models to assess the impact of innate immune response determinants in the generation and subsequent expansion of the TRM cell pool during RSV infection. We show that CD8+ TRM cells expand independently from systemic CD8+ T cells after RSV re-infection. Re-infected MAVS and MyD88/TRIF deficient mice, lacking key components involved in innate immune recognition of RSV and induction of type I interferons (IFN-α/β), display impaired expansion of CD8+ TRM cells and reduction in antigen specific production of granzyme B and IFN-γ. IFN-α treatment of MAVS deficient mice during primary RSV infection restored TRM cell expansion upon re-challenge but failed to recover TRM cell functionality. Our data reveal how innate immunity, including the axis controlling type I IFN induction, instructs and regulates CD8+ TRM cell responses to RSV infection, suggesting possible mechanisms for therapeutic intervention.
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Affiliation(s)
- Augusto Varese
- Respiratory Infections Section, St Mary’s campus, National Heart and Lung Institute, Imperial College London, London, United Kingdom
| | - Joy Nakawesi
- Respiratory Infections Section, St Mary’s campus, National Heart and Lung Institute, Imperial College London, London, United Kingdom
| | - Ana Farias
- Respiratory Infections Section, St Mary’s campus, National Heart and Lung Institute, Imperial College London, London, United Kingdom
| | - Freja C. M. Kirsebom
- Respiratory Infections Section, St Mary’s campus, National Heart and Lung Institute, Imperial College London, London, United Kingdom
| | - Michelle Paulsen
- Respiratory Infections Section, St Mary’s campus, National Heart and Lung Institute, Imperial College London, London, United Kingdom
| | - Rinat Nuriev
- Respiratory Infections Section, St Mary’s campus, National Heart and Lung Institute, Imperial College London, London, United Kingdom
| | - Cecilia Johansson
- Respiratory Infections Section, St Mary’s campus, National Heart and Lung Institute, Imperial College London, London, United Kingdom
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8
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Johansson C, Kirsebom FCM. Neutrophils in respiratory viral infections. Mucosal Immunol 2021; 14:815-827. [PMID: 33758367 PMCID: PMC7985581 DOI: 10.1038/s41385-021-00397-4] [Citation(s) in RCA: 52] [Impact Index Per Article: 17.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2020] [Revised: 11/16/2020] [Accepted: 11/18/2020] [Indexed: 02/04/2023]
Abstract
Viral respiratory infections are a common cause of severe disease, especially in infants, people who are immunocompromised, and in the elderly. Neutrophils, an important innate immune cell, infiltrate the lungs rapidly after an inflammatory insult. The most well-characterized effector mechanisms by which neutrophils contribute to host defense are largely extracellular and the involvement of neutrophils in protection from numerous bacterial and fungal infections is well established. However, the role of neutrophils in responses to viruses, which replicate intracellularly, has been less studied. It remains unclear whether and, by which underlying immunological mechanisms, neutrophils contribute to viral control or confer protection against an intracellular pathogen. Furthermore, neutrophils need to be tightly regulated to avoid bystander damage to host tissues. This is especially relevant in the lung where damage to delicate alveolar structures can compromise gas exchange with life-threatening consequences. It is inherently less clear how neutrophils can contribute to host immunity to viruses without causing immunopathology and/or exacerbating disease severity. In this review, we summarize and discuss the current understanding of how neutrophils in the lung direct immune responses to viruses, control viral replication and spread, and cause pathology during respiratory viral infections.
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Affiliation(s)
- Cecilia Johansson
- National Heart and Lung Institute, Imperial College London, London, UK.
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9
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Arias AV, Lucas DJ, Shafi NI. Respiratory Syncytial Virus Bronchiolitis Complicated by Necrotizing Enterocolitis: A Case Series. Pediatrics 2021; 147:peds.2020-022707. [PMID: 33824182 DOI: 10.1542/peds.2020-022707] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 12/12/2020] [Indexed: 11/24/2022] Open
Abstract
In rare instances, severe respiratory syncytial virus (RSV) infections of the lower respiratory tract can cause life-threatening extrapulmonary complications. In this report, we describe 4 previously healthy, term and late-preterm infants admitted to the PICU with respiratory failure due to RSV bronchiolitis who developed necrotizing enterocolitis shortly after admission. All infants exhibited progressive abdominal distention, had typical radiographic findings, and developed simple or complex ascites. In addition to being managed with broad-spectrum antibiotics and bowel rest, 1 infant was treated with colon resection and ileostomy, 2 had peritoneal drainage procedures for ascites, and one of those later developed small bowel strictures treated with delayed resection and anastomosis. Three were discharged from the hospital without further complications; 1 died of septic shock. In this case series, we describe development of necrotizing enterocolitis in otherwise healthy neonates with severe RSV disease in the absence of traditional risk factors. We hypothesize that a dysregulated proinflammatory response associated with severe RSV disease may alter intestinal blood flow and compromise barriers to bacterial translocation. Enteral feeding intolerance, septic ileus, and/or complex ascites may represent important clinical corollaries in these patients.
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Affiliation(s)
- Anita V Arias
- Division of Pediatric Critical Care, University of Tennessee Health Science Center and Le Bonheur Children's Hospital, Memphis, Tennessee;
| | - Donald J Lucas
- Division of Pediatric Surgery, Naval Medical Center San Diego, California; and.,Department of Surgery, Uniformed Services University of the Health Sciences, Bethesda, Maryland
| | - Nadeem I Shafi
- Division of Pediatric Critical Care, University of Tennessee Health Science Center and Le Bonheur Children's Hospital, Memphis, Tennessee
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10
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Paulsen M, Varese A, Pinpathomrat N, Kirsebom FCM, Paulsen M, Johansson C. MAVS Deficiency Is Associated With a Reduced T Cell Response Upon Secondary RSV Infection in Mice. Front Immunol 2020; 11:572747. [PMID: 33123150 PMCID: PMC7573121 DOI: 10.3389/fimmu.2020.572747] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2020] [Accepted: 09/16/2020] [Indexed: 11/17/2022] Open
Abstract
Infections with respiratory syncytial virus (RSV) occurs repeatedly throughout life because sustained, protective memory responses fail to develop. Why this occurs is not known. During RSV infection the recognition of the virus via the cytosolic RIG-I like receptors and signaling via the adaptor protein MAVS is crucial for mounting an innate immune response. However, if this signaling pathway is important for T cell responses during primary infection and during re-infection is not fully elucidated. We describe a second peak of pro-inflammatory mediators during the primary immune response to RSV that coincides with the arrival of T cells into the lung. This second peak of cytokines/chemokines is regulated differently than the early peak and is largely independent of signaling via MAVS. This was concurrent with Mavs−/− mice mounting a strong T cell response to primary RSV infection, with robust IFN-γ; and Granzyme B production. However, after RSV re-infection, Mavs−/− mice showed fewer CD4+ and CD8+ short term memory T cells and their capacity to produce IFN-γ; and Granzyme B, was decreased. In sum, cytosolic recognition of RSV is important not only for initiating innate anti-viral responses but also for generating or maintaining efficient, short term T cell memory responses.
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Affiliation(s)
- Michelle Paulsen
- Respiratory Infections Section, St Mary's Campus, National Heart and Lung Institute, Imperial College London, London, United Kingdom
| | - Augusto Varese
- Respiratory Infections Section, St Mary's Campus, National Heart and Lung Institute, Imperial College London, London, United Kingdom
| | - Nawamin Pinpathomrat
- Respiratory Infections Section, St Mary's Campus, National Heart and Lung Institute, Imperial College London, London, United Kingdom
| | - Freja C M Kirsebom
- Respiratory Infections Section, St Mary's Campus, National Heart and Lung Institute, Imperial College London, London, United Kingdom
| | - Malte Paulsen
- Respiratory Infections Section, St Mary's Campus, National Heart and Lung Institute, Imperial College London, London, United Kingdom
| | - Cecilia Johansson
- Respiratory Infections Section, St Mary's Campus, National Heart and Lung Institute, Imperial College London, London, United Kingdom
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11
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Melatonin potentials against viral infections including COVID-19: Current evidence and new findings. Virus Res 2020; 287:198108. [PMID: 32768490 PMCID: PMC7405774 DOI: 10.1016/j.virusres.2020.198108] [Citation(s) in RCA: 66] [Impact Index Per Article: 16.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2020] [Revised: 07/30/2020] [Accepted: 07/31/2020] [Indexed: 12/14/2022]
Abstract
Viral infections are dangerous diseases for human health worldwide, which lead to significant morbidity and mortality each year. Because of their importance and the lack of effective therapeutic approaches, further attempts should be made to discover appropriate alternative or complementary treatments. Melatonin, a multifunctional neurohormone mainly synthesized and secreted by the pineal gland, plays some roles in the treatment of viral infections. Regarding a deadly outbreak of COVID-19 across the world, we decided to discuss melatonin functions against various viral infections including COVID-19. Therefore, in this review, we summarize current evidence on melatonin therapy for viral infections with focus on possible underlying mechanisms of melatonin actions.
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12
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Cunningham S, Piedra PA, Martinon-Torres F, Szymanski H, Brackeva B, Dombrecht E, Detalle L, Fleurinck C. Nebulised ALX-0171 for respiratory syncytial virus lower respiratory tract infection in hospitalised children: a double-blind, randomised, placebo-controlled, phase 2b trial. THE LANCET RESPIRATORY MEDICINE 2020; 9:21-32. [PMID: 33002427 DOI: 10.1016/s2213-2600(20)30320-9] [Citation(s) in RCA: 63] [Impact Index Per Article: 15.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/24/2020] [Revised: 05/28/2020] [Accepted: 06/11/2020] [Indexed: 02/02/2023]
Abstract
BACKGROUND Respiratory syncytial virus (RSV) is the most common cause of severe lower respiratory tract infection, with a high global health burden. There are no effective treatments available. ALX-0171 is a novel trivalent Nanobody with antiviral properties against RSV. We aimed to assess the safety and antiviral activity of nebulised ALX-0171 in children admitted to hospital with RSV lower respiratory tract infection. METHODS This double-blind, randomised, placebo-controlled, phase 2b trial was done in 50 hospital paediatric departments across 16 countries. Previously healthy children aged between 28 days to younger than 24 months who were admitted to hospital with RSV acute severe lower respiratory tract infection were randomly assigned in three sequential safety cohorts (3:1) to receive nebulised ALX-0171 (cohort 1 received 3 mg/kg, cohort 2 received 6 mg/kg, and cohort 3 received 9 mg/kg) or placebo once daily for 3 days using web-based randomisation in the sequential safety part (first block size 12, subsequently four). In a parallel part of the study, participants (cohort 4) were randomly assigned (parallel 1:1:1:1) to receive nebulised ALX-0171 3 mg/kg, 6 mg/kg, 9 mg/kg, or placebo (blocks of eight by restricted randomisation). Study drug masking was by two consecutive nebulisations (each either ALX-0171 or placebo) depending on assigned treatment group. The primary outcome was to evaluate time for the RSV viral load to drop to below quantifiable limit, measured by plaque assay on mid-turbinate nasal swabs. Safety, clinical efficacy, pharmacokinetics, viral load by RT-qPCR, and immunogenicity were secondary outcomes. Analysis, including of the primary outcome, was by modified intention to treat (participants receiving at least one dose of study drug as assigned), and safety was assessed in all children who received at least one administration of study drug, as treated. This trial is registered with EudraCT, 2016-001651-49. FINDINGS Between Jan 10, 2017, and April 26, 2018, 175 children (median age 4·8 months [IQR 2·0-10·8]), received at least one dose of study drug (45 received 3 mg/kg of ALX-0171, 43 received 6 mg/kg of ALX-0171, 45 received 9 mg/kg of ALX-0171, and 42 received placebo; the modified intention-to-treat population) commencing at a mean 3·3 days (SD 1·1) from symptom onset. Median time for the viral load to drop to below quantifiable limit on plaque assay was significantly faster for the 3 mg/kg group (median 14·2 h [IQR 5·0-28·0]), 6 mg/kg group (5·1 h [4·7-28·5]), and 9 mg/kg group (5·1 h [4·6-5·9]) than the placebo group (46·1 h [25·2-116·7]; hazard ratio [HR] all ALX-0171 groups vs placebo 2·6 [1·7-3·9]; p<0·0001). Median time for the viral load to drop below quantification limit with RT-qPCR was 95·9 h (IQR 26·7 to not estimable) for the placebo group (n=35) versus 49·4 h (25·1 to 351·4) for all ALX-0171 groups (n=118). Clinical outcomes were not improved by ALX-0171 compared with placebo, with no difference in time to clinical response (oxygen saturation >92% for 4 h in room air and adequate oral feeding) in ALX-0171 groups and the placebo group (median 43·8 h [IQR 21·7-68·5] vs 47·9 h [22·5-76·4]; HR 1·1 [95% CI 0·8-1·6]) or change in the global severity score from baseline to 5 h post-dose on day 2 (-4 [IQR -6 to -2] vs -4 [-6 to -1]; difference in least-squares mean -0·45 [95% CI -1·39 to 0·49]). Serum concentrations of ALX-0171 on day 2 exceeded the concentration estimated to give full RSV neutralisation in the lung at 6 mg/kg and 9 mg/kg doses. Treatment-emergent antidrug antibodies were detected at day 14 in 46 (34%) of 135 patients who received ALX-0171 and ten (26%) of 39 patients who received placebo. Serious adverse events were reported in five (13%) of 40 children in the placebo group and ten (7%) of 135 children in all ALX-0171 groups, leading to study drug discontinuation in three children (two in the 3 mg/kg group and one in the 6 mg/kg group). 13 of 15 serious adverse events (three of four in the 3 mg/kg group, two of three in the 6 mg/kg group, three of three in the 9 mg/kg group, and five of five in the placebo group) were related to worsening respiratory status, and none were considered to be related to the study drug. INTERPRETATION Antivirals against RSV might be unable to improve clinical course once RSV lower respiratory tract infection is established. Future studies of RSV antivirals should focus on earlier intervention and more precise measurement of objective outcomes before the onset of significant lower respiratory tract inflammation. FUNDING Ablynx, a Sanofi Company.
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Affiliation(s)
- Steve Cunningham
- Centre for Inflammation Research, University of Edinburgh, Edinburgh, UK.
| | - Pedro A Piedra
- Department of Molecular Virology and Microbiology and Department of Pediatrics, Baylor College of Medicine, Houston, TX, USA
| | - Federico Martinon-Torres
- Genetics, Vaccines and Pediatric Infectious Diseases Research Group, Instituto de Investigación Sanitaria de Santiago, and Translational Pediatrics and Infectious Diseases, Department of Pediatrics, Hospital Clinico Universitario de Santiago de Compostela, Santiago de Compostela, Spain
| | - Henryk Szymanski
- Department of Paediatrics, St Hedwig of Silesia Hospital, Trzebnica, Poland
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Stambas J, Lu C, Tripp RA. Innate and adaptive immune responses in respiratory virus infection: implications for the clinic. Expert Rev Respir Med 2020; 14:1141-1147. [PMID: 32762572 DOI: 10.1080/17476348.2020.1807945] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
INTRODUCTION The innate immune response is the first line of defense and consists of physical, chemical and cellular defenses. The adaptive immune response is the second line of defense and is pathogen-specific. Innate immunity occurs immediately while adaptive immunity develops upon pathogen exposure, and is long-lasting, highly specific, and sustained by memory T cells. Respiratory virus infection typically induces effective immunity but over-exuberant responses are associated with pathophysiology. Cytokines expressed in response to viral infection can enhance biological responses, activate, and trigger signaling pathways leading to adaptive immunity Vaccines induce immunity, specifically B and T cell responses. Vaccination is generally efficacious, but for many viruses, our understanding of vaccination strategies and immunity is incomplete or in its infancy. Studies that examine innate and adaptive immune responses to respiratory virus infection will aid vaccine development and may reduce the burden of respiratory viral disease. AREAS COVERED A literature search was performed using PubMed. The search covered: innate, adaptive, respiratory virus, vaccine development, B cell, and T cell. EXPERT OPINION Immunity rests on two pillars, i.e. the innate and adaptive immune system, which function together on different tasks to maintain homeostasis. a better understanding of immunity is necessary for disease prevention and intervention.
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Affiliation(s)
- John Stambas
- School of Medicine, Deakin University , Melbourne, Australia
| | - Chunni Lu
- School of Medicine, Deakin University , Melbourne, Australia
| | - Ralph A Tripp
- Department of Infectious Diseases, University of Georgia , Athens, GA, USA
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14
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Comparative Therapeutic Potential of ALX-0171 and Palivizumab against Respiratory Syncytial Virus Clinical Isolate Infection of Well-Differentiated Primary Pediatric Bronchial Epithelial Cell Cultures. Antimicrob Agents Chemother 2020; 64:AAC.02034-19. [PMID: 31767728 DOI: 10.1128/aac.02034-19] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2019] [Accepted: 11/20/2019] [Indexed: 01/09/2023] Open
Abstract
Respiratory syncytial virus (RSV) causes severe lower respiratory tract infections in young infants. There are no RSV-specific treatments available. Ablynx has been developing an anti-RSV F-specific nanobody, ALX-0171. To characterize the therapeutic potential of ALX-0171, we exploited our well-differentiated primary pediatric bronchial epithelial cell (WD-PBEC)/RSV infection model, which replicates several hallmarks of RSV disease in vivo Using 2 clinical isolates (BT2a and Memphis 37), we compared the therapeutic potential of ALX-0171 with that of palivizumab, which is currently prescribed for RSV prophylaxis in high-risk infants. ALX-0171 treatment (900 nM) at 24 h postinfection reduced apically released RSV titers to near or below the limit of detection within 24 h for both strains. Progressively lower doses resulted in concomitantly diminished RSV neutralization. ALX-0171 was approximately 3-fold more potent in this therapeutic RSV/WD-PBEC model than palivizumab (mean 50% inhibitory concentration [IC50] = 346.9 to 363.6 nM and 1,048 to 1,090 nM for ALX-0171 and palivizumab, respectively), irrespective of the clinical isolate. The number of viral genomic copies (GC) was determined by quantitative reverse transcription-PCR (RT-qPCR), and the therapeutic effect of ALX-0171 treatment at 300 and 900 nM was found to be considerably lower and the number of GCs reduced only moderately (0.62 to 1.28 log10 copies/ml). Similar findings were evident for palivizumab. Therefore, ALX-0171 was very potent at neutralizing RSV released from apical surfaces but had only a limited impact on virus replication. The data indicate a clear disparity between viable virus neutralization and GC viral load, the latter of which does not discriminate between viable and neutralized RSV. This report validates the RSV/WD-PBEC model for the preclinical evaluation of RSV antivirals.
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Kirsebom F, Michalaki C, Agueda-Oyarzabal M, Johansson C. Neutrophils do not impact viral load or the peak of disease severity during RSV infection. Sci Rep 2020; 10:1110. [PMID: 31980667 PMCID: PMC6981203 DOI: 10.1038/s41598-020-57969-w] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2019] [Accepted: 01/07/2020] [Indexed: 11/30/2022] Open
Abstract
Lung and airway neutrophils are a hallmark of severe disease in infants with respiratory syncytial virus (RSV)-induced lower respiratory tract infections. Despite their abundance in the lungs during RSV infection of both mice and man, the role of neutrophils in viral control and in immune pathology is not clear. Here, antibody mediated neutrophil depletion was used to investigate the degree to which neutrophils impact the lung immune environment, the control of viral replication and the peak severity of disease after RSV infection of mice. Neutrophil depletion did not substantially affect the levels of inflammatory mediators such as type I interferons, IL-6, TNF-α or IL-1β in response to RSV. In addition, the lack of neutrophils did not change the viral load during RSV infection. Neither neutrophil depletion nor the enhancement of lung neutrophils by administration of the chemoattractant CXCL1 during RSV infection affected disease severity as measured by weight loss. Therefore, in this model of RSV infection, lung neutrophils do not offer obvious benefits to the host in terms of increasing anti-viral inflammatory responses or restricting viral replication and neutrophils do not contribute to disease severity.
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Affiliation(s)
- Freja Kirsebom
- National Heart and Lung Institute, Imperial College London, London, UK
| | | | | | - Cecilia Johansson
- National Heart and Lung Institute, Imperial College London, London, UK.
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16
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Wethington D, Harder O, Uppulury K, Stewart WCL, Chen P, King T, Reynolds SD, Perelson AS, Peeples ME, Niewiesk S, Das J. Mathematical modelling identifies the role of adaptive immunity as a key controller of respiratory syncytial virus in cotton rats. J R Soc Interface 2019; 16:20190389. [PMID: 31771450 DOI: 10.1098/rsif.2019.0389] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Respiratory syncytial virus (RSV) is a common virus that can have varying effects ranging from mild cold-like symptoms to mortality depending on the age and immune status of the individual. We combined mathematical modelling using ordinary differential equations (ODEs) with measurement of RSV infection kinetics in primary well-differentiated human bronchial epithelial cultures in vitro and in immunocompetent and immunosuppressed cotton rats to glean mechanistic details that underlie RSV infection kinetics in the lung. Quantitative analysis of viral titre kinetics in our mathematical model showed that the elimination of infected cells by the adaptive immune response generates unique RSV titre kinetic features including a faster timescale of viral titre clearance than viral production, and a monotonic decrease in the peak RSV titre with decreasing inoculum dose. Parameter estimation in the ODE model using a nonlinear mixed effects approach revealed a very low rate (average single-cell lifetime > 10 days) of cell lysis by RSV before the adaptive immune response is initiated. Our model predicted negligible changes in the RSV titre kinetics at early times post-infection (less than 5 dpi) but a slower decay in RSV titre in immunosuppressed cotton rats compared to that in non-suppressed cotton rats at later times (greater than 5 dpi) in silico. These predictions were in excellent agreement with the experimental results. Our combined approach quantified the importance of the adaptive immune response in suppressing RSV infection in cotton rats, which could be useful in testing RSV vaccine candidates.
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Affiliation(s)
- Darren Wethington
- Battelle Center for Mathematical Medicine, The Research Institute at the Nationwide Children's Hospital, 700 Children's Drive, Columbus, OH 43205, USA
| | - Olivia Harder
- College of Veterinary Medicine, The Ohio State University, Columbus, OH 43210, USA
| | - Karthik Uppulury
- Battelle Center for Mathematical Medicine, The Research Institute at the Nationwide Children's Hospital, 700 Children's Drive, Columbus, OH 43205, USA
| | - William C L Stewart
- Battelle Center for Mathematical Medicine, The Research Institute at the Nationwide Children's Hospital, 700 Children's Drive, Columbus, OH 43205, USA.,Department of Pediatrics, The Ohio State University, Columbus, OH 43210, USA.,Department of Statistics, The Ohio State University, Columbus, OH 43210, USA
| | - Phylip Chen
- Vaccines and Immunity, Abigail Wexner Research Institute at the Nationwide Children's Hospital, 700 Children's Drive, Columbus, OH 43205, USA
| | - Tiffany King
- Vaccines and Immunity, Abigail Wexner Research Institute at the Nationwide Children's Hospital, 700 Children's Drive, Columbus, OH 43205, USA.,Biomedical Sciences Graduate Program, The Ohio State University, Columbus, OH 43210, USA
| | - Susan D Reynolds
- Center for Perinatal Research, Abigail Wexner Research Institute at the Nationwide Children's Hospital, 700 Children's Drive, Columbus, OH 43205, USA.,Department of Pediatrics, The Ohio State University, Columbus, OH 43210, USA
| | - Alan S Perelson
- Theoretical Biology and Biophysics, Los Alamos National Laboratory, Los Alamos, NM 87545, USA
| | - Mark E Peeples
- Vaccines and Immunity, Abigail Wexner Research Institute at the Nationwide Children's Hospital, 700 Children's Drive, Columbus, OH 43205, USA.,Department of Pediatrics, The Ohio State University, Columbus, OH 43210, USA.,Biomedical Sciences Graduate Program, The Ohio State University, Columbus, OH 43210, USA
| | - Stefan Niewiesk
- College of Veterinary Medicine, The Ohio State University, Columbus, OH 43210, USA
| | - Jayajit Das
- Battelle Center for Mathematical Medicine, The Research Institute at the Nationwide Children's Hospital, 700 Children's Drive, Columbus, OH 43205, USA.,Department of Pediatrics, The Ohio State University, Columbus, OH 43210, USA.,Department of Physics, The Ohio State University, Columbus, OH 43210, USA.,Biophysics Graduate Program, The Ohio State University, Columbus, OH 43210, USA
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Abstract
Respiratory syncytial virus (RSV) can cause severe lower respiratory tract infections especially in infants, immunocompromised individuals and the elderly and is the most common cause of infant hospitalisation in the developed world. The immune responses against RSV are crucial for viral control and clearance but, if dysregulated, can also result in immunopathology and impaired gas exchange. Lung immunity to RSV and other respiratory viruses begins with the recruitment of immune cells from the bloodstream into the lungs. This inflammatory process is controlled largely by chemokines, which are small proteins that are produced in response to innate immune detection of the virus or the infection process. These chemokines serve as chemoattractants for granulocytes, monocytes, lymphocytes and other leukocytes. In this review, we highlight recent advances in the field of RSV infection and disease, focusing on how chemokines regulate virus-induced inflammation.
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Affiliation(s)
- Rinat Nuriev
- National Heart and Lung Institute, Imperial College London, London, UK.,I. Mechnikov Research Institute for Vaccines and Sera, Moscow, Russian Federation
| | - Cecilia Johansson
- National Heart and Lung Institute, Imperial College London, London, UK
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18
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Heykers A, Leemans A, Van der Gucht W, De Schryver M, Cos P, Delputte P. Differences in Susceptibility of Human and Mouse Macrophage Cell Lines to Respiratory Syncytial Virus Infection. Intervirology 2019; 62:134-144. [PMID: 31533107 DOI: 10.1159/000502674] [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: 12/11/2018] [Accepted: 08/12/2019] [Indexed: 11/19/2022] Open
Abstract
OBJECTIVES Differences have been observed in the susceptibility of macrophage cell lines to respiratory syncytial virus (RSV) infection. In this study, we evaluated whether the type of macrophage cell line and RSV strain used have an influence on the infectivity and production of progeny virus. METHODS Both human and murine macrophage-like cell lines were infected with different RSV strains, both lab strains as well as clinical isolates. The infection was evaluated after 24 and 72 h by immunofluorescence staining and microscopic analysis, and the production of new virus particles was determined by plaque assay. RESULTS Susceptibility of macrophages to RSV was influenced by the RSV strain used but was mostly dependent on the macrophage cell line. Numbers of infected cells and virus production were generally very low or absent in murine cell lines. In human cell lines, clear infection was observed associated with production of new virus particles. CONCLUSION Differences in susceptibility of macrophage cell lines to RSV infection are primarily related to the species of origin of the cell line but are also influenced by the RSV strain.
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Affiliation(s)
- Annick Heykers
- Laboratory of Microbiology, Parasitology and Hygiene, University of Antwerp, Antwerp, Belgium
| | - Annelies Leemans
- Laboratory of Microbiology, Parasitology and Hygiene, University of Antwerp, Antwerp, Belgium
| | - Winke Van der Gucht
- Laboratory of Microbiology, Parasitology and Hygiene, University of Antwerp, Antwerp, Belgium
| | - Marjorie De Schryver
- Laboratory of Microbiology, Parasitology and Hygiene, University of Antwerp, Antwerp, Belgium
| | - Paul Cos
- Laboratory of Microbiology, Parasitology and Hygiene, University of Antwerp, Antwerp, Belgium
| | - Peter Delputte
- Laboratory of Microbiology, Parasitology and Hygiene, University of Antwerp, Antwerp, Belgium,
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Carvajal JJ, Avellaneda AM, Salazar-Ardiles C, Maya JE, Kalergis AM, Lay MK. Host Components Contributing to Respiratory Syncytial Virus Pathogenesis. Front Immunol 2019; 10:2152. [PMID: 31572372 PMCID: PMC6753334 DOI: 10.3389/fimmu.2019.02152] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2019] [Accepted: 08/27/2019] [Indexed: 12/22/2022] Open
Abstract
Respiratory syncytial virus (RSV) is the most prevalent viral etiological agent of acute respiratory tract infection. Although RSV affects people of all ages, the disease is more severe in infants and causes significant morbidity and hospitalization in young children and in the elderly. Host factors, including an immature immune system in infants, low lymphocyte levels in patients under 5 years old, and low levels of RSV-specific neutralizing antibodies in the blood of adults over 65 years of age, can explain the high susceptibility to RSV infection in these populations. Other host factors that correlate with severe RSV disease include high concentrations of proinflammatory cytokines such as interleukins (IL)-6, IL-8, tumor necrosis factor (TNF)-α, and thymic stromal lymphopoitein (TSLP), which are produced in the respiratory tract of RSV-infected individuals, accompanied by a strong neutrophil response. In addition, data from studies of RSV infections in humans and in animal models revealed that this virus suppresses adaptive immune responses that could eliminate it from the respiratory tract. Here, we examine host factors that contribute to RSV pathogenesis based on an exhaustive review of in vitro infection in humans and in animal models to provide insights into the design of vaccines and therapeutic tools that could prevent diseases caused by RSV.
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Affiliation(s)
- Jonatan J. Carvajal
- Departamento de Biotecnología, Facultad de Ciencias del Mar y Recursos Biológicos, Universidad de Antofagasta, Antofagasta, Chile
| | - Andrea M. Avellaneda
- Departamento de Biotecnología, Facultad de Ciencias del Mar y Recursos Biológicos, Universidad de Antofagasta, Antofagasta, Chile
| | - Camila Salazar-Ardiles
- Departamento de Biotecnología, Facultad de Ciencias del Mar y Recursos Biológicos, Universidad de Antofagasta, Antofagasta, Chile
| | - Jorge E. Maya
- Departamento de Biotecnología, Facultad de Ciencias del Mar y Recursos Biológicos, Universidad de Antofagasta, Antofagasta, Chile
| | - Alexis M. Kalergis
- Millennium Institute on Immunology and Immunotherapy, Departamento de Genética Molecular y Microbiología, Facultad de Ciencias Biológicas, Pontificia Universidad de Chile, Santiago, Chile
- Departamento de Endocrinología, Facultad de Medicina, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Margarita K. Lay
- Departamento de Biotecnología, Facultad de Ciencias del Mar y Recursos Biológicos, Universidad de Antofagasta, Antofagasta, Chile
- Millennium Institute on Immunology and Immunotherapy, Departamento de Genética Molecular y Microbiología, Facultad de Ciencias Biológicas, Pontificia Universidad de Chile, Santiago, Chile
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20
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de Souza GF, Muraro SP, Santos LD, Monteiro APT, da Silva AG, de Souza APD, Stein RT, Bozza PT, Porto BN. Macrophage migration inhibitory factor (MIF) controls cytokine release during respiratory syncytial virus infection in macrophages. Inflamm Res 2019; 68:481-491. [PMID: 30944975 DOI: 10.1007/s00011-019-01233-z] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2018] [Revised: 03/15/2019] [Accepted: 03/29/2019] [Indexed: 01/01/2023] Open
Abstract
OBJECTIVE AND DESIGN Respiratory syncytial virus (RSV) is the major cause of infection in children up to 2 years old and reinfection is very common among patients. Tissue damage in the lung caused by RSV leads to an immune response and infected cells activate multiple signaling pathways and massive production of inflammatory mediators like macrophage migration inhibitory factor (MIF), a pro-inflammatory cytokine. Therefore, we sought to investigate the role of MIF during RSV infection in macrophages. METHODS We evaluated MIF expression in BALB/c mice-derived macrophages stimulated with different concentrations of RSV by Western blot and real-time PCR. Additionally, different inhibitors of signaling pathways and ROS were used to evaluate their importance for MIF expression. Furthermore, we used a specific MIF inhibitor, ISO-1, to evaluate the role of MIF in viral clearance and in RSV-induced TNF-α, MCP-1 and IL-10 release from macrophages. RESULTS We showed that RSV induces MIF expression dependently of ROS, 5-LOX, COX and PI3K activation. Moreover, viral replication is necessary for RSV-triggered MIF expression. Differently, p38 MAPK in only partially needed for RSV-induced MIF expression. In addition, MIF is important for the release of TNF-α, MCP-1 and IL-10 triggered by RSV in macrophages. CONCLUSIONS In conclusion, we demonstrate that MIF is expressed during RSV infection and controls the release of pro-inflammatory cytokines from macrophages in an in vitro model.
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Affiliation(s)
- Gabriela F de Souza
- Laboratory of Clinical and Experimental Immunology, Infant Center, School of Medicine, Pontifical Catholic University of Rio Grande do Sul (PUCRS), Porto Alegre, RS, Brazil
| | - Stéfanie P Muraro
- Laboratory of Clinical and Experimental Immunology, Infant Center, School of Medicine, Pontifical Catholic University of Rio Grande do Sul (PUCRS), Porto Alegre, RS, Brazil
| | - Leonardo D Santos
- Laboratory of Clinical and Experimental Immunology, Infant Center, School of Medicine, Pontifical Catholic University of Rio Grande do Sul (PUCRS), Porto Alegre, RS, Brazil
| | - Ana Paula T Monteiro
- Laboratory of Immunopharmacology, Oswaldo Cruz Institute, Oswaldo Cruz Foundation (FIOCRUZ), Rio de Janeiro, RJ, Brazil
| | - Amanda G da Silva
- Laboratory of Clinical and Experimental Immunology, Infant Center, School of Medicine, Pontifical Catholic University of Rio Grande do Sul (PUCRS), Porto Alegre, RS, Brazil
| | - Ana Paula D de Souza
- Laboratory of Clinical and Experimental Immunology, Infant Center, School of Medicine, Pontifical Catholic University of Rio Grande do Sul (PUCRS), Porto Alegre, RS, Brazil
| | - Renato T Stein
- Laboratory of Pediatric Respirology, Infant Center, School of Medicine, Pontifical Catholic University of Rio Grande do Sul (PUCRS), Porto Alegre, RS, Brazil
| | - Patrícia T Bozza
- Laboratory of Immunopharmacology, Oswaldo Cruz Institute, Oswaldo Cruz Foundation (FIOCRUZ), Rio de Janeiro, RJ, Brazil
| | - Bárbara N Porto
- Laboratory of Clinical and Experimental Immunology, Infant Center, School of Medicine, Pontifical Catholic University of Rio Grande do Sul (PUCRS), Porto Alegre, RS, Brazil.
- Program in Translational Medicine, The Hospital for Sick Children, Toronto, ON, Canada.
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21
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Kirsebom FCM, Kausar F, Nuriev R, Makris S, Johansson C. Neutrophil recruitment and activation are differentially dependent on MyD88/TRIF and MAVS signaling during RSV infection. Mucosal Immunol 2019; 12:1244-1255. [PMID: 31358860 PMCID: PMC6778055 DOI: 10.1038/s41385-019-0190-0] [Citation(s) in RCA: 40] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2018] [Revised: 06/14/2019] [Accepted: 06/29/2019] [Indexed: 02/04/2023]
Abstract
Respiratory syncytial virus (RSV) is a leading cause of severe lower respiratory tract infections, especially in infants. Lung neutrophilia is a hallmark of RSV disease but the mechanism by which neutrophils are recruited and activated is unclear. Here, we investigate the innate immune signaling pathways underlying neutrophil recruitment and activation in RSV-infected mice. We show that MyD88/TRIF signaling is essential for lung neutrophil recruitment while MAVS signaling, leading to type I IFN production, is necessary for neutrophil activation. Consistent with that notion, administration of type I IFNs to the lungs of RSV-infected Mavs-/- mice partially activates lung neutrophils recruited via the MyD88/TRIF pathway. Conversely, lack of neutrophil recruitment to the lungs of RSV-infected Myd88/Trif-/- mice can be corrected by administration of chemoattractants and those neutrophils become fully activated. Interestingly, Myd88/Trif-/- mice did not have increased lung viral loads during RSV infection, suggesting that neutrophils are dispensable for viral control. Thus, two distinct pathogen sensing pathways collaborate for neutrophil recruitment and full activation during RSV infection.
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Affiliation(s)
- Freja C. M. Kirsebom
- 0000 0001 2113 8111grid.7445.2National Heart and Lung Institute, Imperial College London, St Mary’s Hospital, Norfolk Place, London, W2 1PG UK
| | - Fahima Kausar
- 0000 0001 2113 8111grid.7445.2National Heart and Lung Institute, Imperial College London, St Mary’s Hospital, Norfolk Place, London, W2 1PG UK
| | - Rinat Nuriev
- 0000 0001 2113 8111grid.7445.2National Heart and Lung Institute, Imperial College London, St Mary’s Hospital, Norfolk Place, London, W2 1PG UK
| | - Spyridon Makris
- 0000 0001 2113 8111grid.7445.2National Heart and Lung Institute, Imperial College London, St Mary’s Hospital, Norfolk Place, London, W2 1PG UK ,0000000122478951grid.14105.31Present Address: MRC/UCL Lab for Molecular Cell Biology, London, UK
| | - Cecilia Johansson
- 0000 0001 2113 8111grid.7445.2National Heart and Lung Institute, Imperial College London, St Mary’s Hospital, Norfolk Place, London, W2 1PG UK
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22
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Muraro SP, De Souza GF, Gallo SW, Da Silva BK, De Oliveira SD, Vinolo MAR, Saraiva EM, Porto BN. Respiratory Syncytial Virus induces the classical ROS-dependent NETosis through PAD-4 and necroptosis pathways activation. Sci Rep 2018; 8:14166. [PMID: 30242250 PMCID: PMC6154957 DOI: 10.1038/s41598-018-32576-y] [Citation(s) in RCA: 101] [Impact Index Per Article: 16.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2018] [Accepted: 09/11/2018] [Indexed: 12/20/2022] Open
Abstract
Respiratory syncytial virus (RSV) is a major cause of diseases of the respiratory tract in young children and babies, being mainly associated with bronchiolitis. RSV infection occurs primarily in pulmonary epithelial cells and, once infection is established, an immune response is triggered and neutrophils are recruited. In this study, we investigated the mechanisms underlying NET production induced by RSV. We show that RSV induced the classical ROS-dependent NETosis in human neutrophils and that RSV was trapped in DNA lattices coated with NE and MPO. NETosis induction by RSV was dependent on signaling by PI3K/AKT, ERK and p38 MAPK and required histone citrullination by PAD-4. In addition, RIPK1, RIPK3 and MLKL were essential to RSV-induced NETosis. MLKL was also necessary to neutrophil necrosis triggered by the virus, likely promoting membrane-disrupting pores, leading to neutrophil lysis and NET extrusion. Finally, we found that RSV infection of alveolar epithelial cells or lung fibroblasts triggers NET-DNA release by neutrophils, indicating that neutrophils can identify RSV-infected cells and respond to them by releasing NETs. The identification of the mechanisms responsible to mediate RSV-induced NETosis may prove valuable to the design of new therapeutic approaches to treat the inflammatory consequences of RSV bronchiolitis in young children.
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Affiliation(s)
- Stéfanie P Muraro
- Laboratory of Clinical and Experimental Immunology, Infant Center, School of Medicine, Pontifical Catholic University of Rio Grande do Sul (PUCRS), Porto Alegre, RS, 90610-000, Brazil
| | - Gabriela F De Souza
- Laboratory of Clinical and Experimental Immunology, Infant Center, School of Medicine, Pontifical Catholic University of Rio Grande do Sul (PUCRS), Porto Alegre, RS, 90610-000, Brazil
| | - Stephanie W Gallo
- Laboratory of Immunology and Microbiology, School of Sciences, Pontifical Catholic University of Rio Grande do Sul (PUCRS), Porto Alegre, RS, 90610-000, Brazil
| | - Bruna K Da Silva
- Laboratory of Immunoinflammation, Department of Genetics, Evolution and Bioagents, Institute of Biology, University of Campinas (UNICAMP), Campinas, SP, 13083-862, Brazil
| | - Sílvia D De Oliveira
- Laboratory of Immunology and Microbiology, School of Sciences, Pontifical Catholic University of Rio Grande do Sul (PUCRS), Porto Alegre, RS, 90610-000, Brazil
| | - Marco Aurélio R Vinolo
- Laboratory of Immunoinflammation, Department of Genetics, Evolution and Bioagents, Institute of Biology, University of Campinas (UNICAMP), Campinas, SP, 13083-862, Brazil
| | - Elvira M Saraiva
- Laboratory of Immunobiology of Leishmaniasis, Department of Immunology, Institute of Microbiology Paulo de Góes, Federal University of Rio de Janeiro (UFRJ), Rio de Janeiro, RJ, 21941-902, Brazil
| | - Bárbara N Porto
- Laboratory of Clinical and Experimental Immunology, Infant Center, School of Medicine, Pontifical Catholic University of Rio Grande do Sul (PUCRS), Porto Alegre, RS, 90610-000, Brazil.
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23
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Interactive effects of age and respiratory virus on severe lower respiratory infection. Epidemiol Infect 2018; 146:1861-1869. [PMID: 30047350 DOI: 10.1017/s0950268818002017] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
We investigated risk factors for severe acute lower respiratory infections (ALRI) among hospitalised children 8 months were at greater risk from influenza-associated ICU admissions and long hospital stay. Children with ADV had increased LOS across all ages. In the first 2 years of life, the effects of different viruses on ALRI severity varies with age. Our findings help to identify specific ages that would most benefit from virus-specific interventions such as vaccines and antivirals.
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24
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Differential Responses by Human Respiratory Epithelial Cell Lines to Respiratory Syncytial Virus Reflect Distinct Patterns of Infection Control. J Virol 2018; 92:JVI.02202-17. [PMID: 29769339 DOI: 10.1128/jvi.02202-17] [Citation(s) in RCA: 40] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2017] [Accepted: 05/02/2018] [Indexed: 12/15/2022] Open
Abstract
Respiratory syncytial virus (RSV) infects small foci of respiratory epithelial cells via infected droplets. Infection induces expression of type I and III interferons (IFNs) and proinflammatory cytokines, the balance of which may restrict viral replication and affect disease severity. We explored this balance by infecting two respiratory epithelial cell lines with low doses of recombinant RSV expressing green fluorescent protein (rgRSV). A549 cells were highly permissive, whereas BEAS-2B cells restricted infection to individual cells or small foci. After infection, A549 cells expressed higher levels of IFN-β-, IFN-λ-, and NF-κB-inducible proinflammatory cytokines. In contrast, BEAS-2B cells expressed higher levels of antiviral interferon-stimulated genes, pattern recognition receptors, and other signaling intermediaries constitutively and after infection. Transcriptome analysis revealed that constitutive expression of antiviral and proinflammatory genes predicted responses by each cell line. These two cell lines provide a model for elucidating critical mediators of local control of viral infection in respiratory epithelial cells.IMPORTANCE Airway epithelium is both the primary target of and the first defense against respiratory syncytial virus (RSV). Whether RSV replicates and spreads to adjacent epithelial cells depends on the quality of their innate immune responses. A549 and BEAS-2B are alveolar and bronchial epithelial cell lines, respectively, that are often used to study RSV infection. We show that A549 cells are permissive to RSV infection and express genes characteristic of a proinflammatory response. In contrast, BEAS-2B cells restrict infection and express genes characteristic of an antiviral response associated with expression of type I and III interferons. Transcriptome analysis of constitutive gene expression revealed patterns that may predict the response of each cell line to infection. This study suggests that restrictive and permissive cell lines may provide a model for identifying critical mediators of local control of infection and stresses the importance of the constitutive antiviral state for the response to viral challenge.
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25
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Perk Y, Özdil M. Respiratory syncytial virüs infections in neonates and infants. TURK PEDIATRI ARSIVI 2018; 53:63-70. [PMID: 30116126 PMCID: PMC6089794 DOI: 10.5152/turkpediatriars.2018.6939] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/09/2017] [Accepted: 10/23/2017] [Indexed: 12/22/2022]
Abstract
Respiratory syncytial virus is one of the major causes of respiratory tract infections during infancy with high rates of hospitalization and mortality during the first years of life. It is the most common cause of acute bronchiolitis and viral pneumonia in children below two years of age and second the most common cause of postneonatal infant mortality all around the world following malaria. In addition, the virus has been causally linked to recurrent wheezing and associated with pediatric asthma. The respiratory syncytial virus infections tend to be severe in high risk patients such as patients below six months of age, with prematurity, congenital heart diseases, neuromuscular diseases and immune deficiencies. No specific treatment is available for respiratory syncytial virus infections to date. Severe cases require supportive therapy, mainly oxygen supplementation and hydration, and less frequently, ventilatory support. Because there is no vaccine to prevent respiratory syncytial virus infections or clinically effective treatment to administer to children with respiratory syncytial virus infection, immunoprophylaxis with palivizumab is currently the only method for reducing morbidity associated with severe respiratory syncytial virus in high-risk infants.
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Affiliation(s)
- Yıldız Perk
- Department of Pediatrics, Division of Neonatology, İstanbul University Cerrahpaşa School of Medicine, İstanbul, Turkey
| | - Mine Özdil
- Department of Pediatrics, Division of Neonatology, İstanbul University Cerrahpaşa School of Medicine, İstanbul, Turkey
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26
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Label-free quantitative proteomics reveals fibrinopeptide B and heparin cofactor II as potential serum biomarkers in respiratory syncytial virus-infected mice treated with Qingfei oral liquid formula. Chin J Nat Med 2018; 16:241-251. [DOI: 10.1016/s1875-5364(18)30054-2] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2017] [Indexed: 01/28/2023]
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27
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Yon DK, Min CY, Ha EK, Jee HM, Jung YH, Lee KS, Sheen YH, Han MY. Clinical characteristics and genetic variation in respiratory syncytial virus isolated from infants hospitalized due to acute bronchiolitis in Korea during winter season 2016–2017. ALLERGY ASTHMA & RESPIRATORY DISEASE 2018. [DOI: 10.4168/aard.2018.6.2.110] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Affiliation(s)
- Dong Keon Yon
- Department of Pediatrics, CHA Bundang Medical Center, CHA University School of Medicine, Seongnam, Korea
| | - Chae-Yeon Min
- Department of Pediatrics, CHA Bundang Medical Center, CHA University School of Medicine, Seongnam, Korea
| | - Eun Kyo Ha
- Department of Pediatrics, CHA Bundang Medical Center, CHA University School of Medicine, Seongnam, Korea
| | - Hye Mi Jee
- Department of Pediatrics, CHA Bundang Medical Center, CHA University School of Medicine, Seongnam, Korea
| | - Young-Ho Jung
- Department of Pediatrics, CHA Bundang Medical Center, CHA University School of Medicine, Seongnam, Korea
| | - Kyung Suk Lee
- Department of Pediatrics, CHA Bundang Medical Center, CHA University School of Medicine, Seongnam, Korea
| | - Youn Ho Sheen
- Department of Pediatrics, CHA Gangnam Medical Center, CHA University School of Medicine, Seoul, Korea
| | - Man Yong Han
- Department of Pediatrics, CHA Bundang Medical Center, CHA University School of Medicine, Seongnam, Korea
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28
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Tahamtan A, Samieipoor Y, Nayeri FS, Rahbarimanesh AA, Izadi A, Rashidi-Nezhad A, Tavakoli-Yaraki M, Farahmand M, Bont L, Shokri F, Mokhatri-Azad T, Salimi V. Effects of cannabinoid receptor type 2 in respiratory syncytial virus infection in human subjects and mice. Virulence 2017; 9:217-230. [PMID: 28992427 PMCID: PMC5955186 DOI: 10.1080/21505594.2017.1389369] [Citation(s) in RCA: 39] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
An accumulating body of evidence suggests that the endocannabinoid system plays a significant role in pathophysiological processes and impacts disease severity. Here we investigate the possible role of a cannabinoid receptor type 2 (CB2) functional variant in determining disease severity and the potential pharmacological therapeutic effects of CB2 activation in viral respiratory infection. The common missense variant (CAA/CGG; Q63R) of the gene-encoding CB2 receptor (CNR2) was evaluated in 90 inpatient and 90 outpatient children with acute respiratory tract infection (ARTI). The frequency distribution of respiratory syncytial virus (RSV)-the main cause of severe cases of bronchiolitis and pneumonia in children-was studied in all collected samples. The mechanism through which CB2 affects clinical outcomes in case of RSV infection was studied in Balb/c mice model using AM630 as a CB2 antagonist. The potential therapeutic effect of CB2 activation during RSV infection was studied using a selective agonist, JWH133. The CB2 Q63R variation was associated with increased risk of hospitalization in children with ARTI. Children carrying the QQ genotype were more prone to developing severe ARTI (OR = 3.275, 95% CI: 1.221–8.705; p = 0.019). Of all the children enrolled in the study, 83 patients (46.1%) were found positive for RSV infection. The associated risk of developing severe ARTI following RSV infection increased more than two-fold in children carrying the Q allele (OR = 2.148, 95% CI: 1.092–4.224; p = 0.026). In mice, the blockade of CB2 by AM630 during RSV infection enhanced the influx of BAL cells and production of cytokines/chemokines while exaggerating lung pathology. CB2 activation by JWH133 reduces the influx of BAL cells and production of cytokines/chemokines while alleviating lung pathology. Collectively, CB2 is associated with RSV severity during infancy and may serve as a therapeutic target in RSV infection through the alleviation of virus-associated immunopathology.
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Affiliation(s)
- Alireza Tahamtan
- a Department of Virology , School of Public Health, Tehran University of Medical Sciences , Tehran , Iran
| | - Yazdan Samieipoor
- a Department of Virology , School of Public Health, Tehran University of Medical Sciences , Tehran , Iran
| | - Fatemeh Sadat Nayeri
- b Fetal and Neonatal Research Center , Tehran University of Medical Sciences , Tehran , Iran
| | | | - Anahita Izadi
- c Bahrami Children Hospital , Tehran University of Medical Sciences , Tehran , Iran
| | - Ali Rashidi-Nezhad
- d Maternal, Fetal and Neonatal Research Center , Tehran University of Medical Sciences , Tehran , Iran
| | | | - Mohammad Farahmand
- a Department of Virology , School of Public Health, Tehran University of Medical Sciences , Tehran , Iran
| | - Louis Bont
- f University Medical Center Utrecht (UMCU), Wilhelmina Children's Hospital (WKZ) , Department of Pediatrics , Utrecht , The Netherlands
| | - Fazel Shokri
- g Department of Immunology , School of Public Health, Tehran University of Medical Sciences , Tehran , Iran
| | - Talat Mokhatri-Azad
- a Department of Virology , School of Public Health, Tehran University of Medical Sciences , Tehran , Iran
| | - Vahid Salimi
- a Department of Virology , School of Public Health, Tehran University of Medical Sciences , Tehran , Iran
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29
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Pulmonary Susceptibility of Neonates to Respiratory Syncytial Virus Infection: A Problem of Innate Immunity? J Immunol Res 2017; 2017:8734504. [PMID: 29250560 PMCID: PMC5700507 DOI: 10.1155/2017/8734504] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2017] [Accepted: 10/09/2017] [Indexed: 12/13/2022] Open
Abstract
Human respiratory syncytial virus (RSV) is a common and highly contagious viral agent responsible for acute lower respiratory infection in infants. This pathology characterized by mucus hypersecretion and a disturbed T cell immune response is one of the major causes of infant hospitalization for severe bronchiolitis. Although different risk factors are associated with acute RSV bronchiolitis, the immunological factors contributing to the susceptibility of RSV infection in infants are not clearly elucidated. Epidemiological studies have established that the age at initial infection plays a central role in the severity of the disease. Thus, neonatal susceptibility is intrinsically linked to the immunological characteristics of the young pulmonary mucosa. Early life is a critical period for the lung development with the first expositions to external environmental stimuli and microbiota colonization. Furthermore, neonates display a lung immune system that profoundly differs to those from adults, with the predominance of type 2 immune cells. In this review, we discuss the latest information about the lung immune environment in the early period of life at a steady state and upon RSV infection and how we can modulate neonatal susceptibility to RSV infection.
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