scholarly journals 2385 Role of the antioxidant enzyme catalase in respiratory syncytial virus infection

2018 ◽  
Vol 2 (S1) ◽  
pp. 26-26
Author(s):  
Maria Ansar ◽  
Jeffrey M. Chambliss ◽  
Naryana Komaravelli ◽  
Teodora Ivanciuc ◽  
Antonella Casola ◽  
...  
Keyword(s):  
Respiratory Syncytial Virus ◽  
Antioxidant Enzyme ◽  
Catalase Activity ◽  
Immune Cell ◽  
Patient Treatment ◽  
Rsv Infection ◽  
Syncytial Virus ◽  
Antioxidant Enzyme Catalase ◽  
Disease Parameters

OBJECTIVES/SPECIFIC AIMS: The goal of this study is to further evaluate underlying disease parameters in respiratory syncytial virus (RSV) infection, that is reduction in antioxidant potential, and determining if supplementation of the antioxidant enzyme catalase could be employed as a potential therapeutic. METHODS/STUDY POPULATION: Nasopharyngeal secretions were obtained from patients (<2 years old) verified for RSV infection, and assessed for catalase activity and correlated with disease parameters. In addition, the BALB/c animal model of RSV infection was utilized to directly study the effect of supplemental catalase on RSV-related disease parameters in vivo. The catalase formulation used in these studies is pegylated, and has been tested to provide long-term increased catalase activity in vivo. We are also currently working on designing an in vitro model of catalase supplementation in A549 bronchial epithelial cells. RESULTS/ANTICIPATED RESULTS: Our preliminary data shows that patients with more severe disease (based on hospitalization, oxygen supplementation) have significantly lower levels of catalase activity (p<0.02). Additionally, when pegylated-Catalase (PG-CAT) treatment is utilized in RSV infection of mice, there is significant improvement in several disease parameters. PG-CAT-treated mice show an attenuated body weight loss (p<0.001) and clinical disease (p<0.02), and also have lower levels of key pro-inflammatory cytokines including CXCL1 and TNF-α. PG-CAT treatment also resulted in a minor decrease in viral titer, which is being further evaluated. In addition, PG-CAT treatment resulted in an improvement in airway hyperresponsiveness observed at baseline, we are further characterizing this improvement and also conducting methacholine challenges. Currently, we are working to determine the underlying mechanism through which PG-CAT results in these improvements, and whether it is through changes in immune cell populations, cellular signaling or apoptosis signaling pathways (i.e., caspases). DISCUSSION/SIGNIFICANCE OF IMPACT: RSV is the leading cause of viral pneumonia and bronchiolitis in infants, with no vaccines or effective therapeutics available currently. Our study indicates that catalase activity could be used as a potential correlate for disease severity and be used as an indicator of disease during patient treatment. Additionally, and more importantly supplementation of catalase could be used as a potential therapeutic for treatment of RSV.

scholarly journals Evaluation of the Safety and Immune Efficacy of Recombinant Human Respiratory Syncytial Virus Strain Long Live Attenuated Vaccine Candidates

2021 ◽  
Author(s):  
Li-Nan Wang ◽  
Xiang-Lei Peng ◽  
Min Xu ◽  
Yuan-Bo Zheng ◽  
Yue-Ying Jiao ◽  
...  
Keyword(s):  
Respiratory Syncytial Virus ◽  
Gene Deletion ◽  
Human Respiratory Syncytial Virus ◽  
Temperature Sensitive ◽  
T7 Promoter ◽  
Vaccine Candidates ◽  
Rsv Infection ◽  
Syncytial Virus

AbstractHuman respiratory syncytial virus (RSV) infection is the leading cause of lower respiratory tract illness (LRTI), and no vaccine against LRTI has proven to be safe and effective in infants. Our study assessed attenuated recombinant RSVs as vaccine candidates to prevent RSV infection in mice. The constructed recombinant plasmids harbored (5′ to 3′) a T7 promoter, hammerhead ribozyme, RSV Long strain antigenomic cDNA with cold-passaged (cp) mutations or cp combined with temperature-sensitive attenuated mutations from the A2 strain (A2cpts) or further combined with SH gene deletion (A2cptsΔSH), HDV ribozyme (δ), and a T7 terminator. These vectors were subsequently co-transfected with four helper plasmids encoding N, P, L, and M2-1 viral proteins into BHK/T7-9 cells, and the recovered viruses were then passaged in Vero cells. The rescued recombinant RSVs (rRSVs) were named rRSV-Long/A2cp, rRSV-Long/A2cpts, and rRSV-Long/A2cptsΔSH, respectively, and stably passaged in vitro, without reversion to wild type (wt) at sites containing introduced mutations or deletion. Although rRSV-Long/A2cpts and rRSV-Long/A2cptsΔSH displayed  temperature-sensitive (ts) phenotype in vitro and in vivo, all rRSVs were significantly attenuated in vivo. Furthermore, BALB/c mice immunized with rRSVs produced Th1-biased immune response, resisted wtRSV infection, and were free from enhanced respiratory disease. We showed that the combination of ΔSH with attenuation (att) mutations of cpts contributed to improving att phenotype, efficacy, and gene stability of rRSV. By successfully introducing att mutations and SH gene deletion into the RSV Long parent and producing three rRSV strains, we have laid an important foundation for the development of RSV live attenuated vaccines.

scholarly journals Inhibitory Effect of Sargassum fusiforme and Its Components on Replication of Respiratory Syncytial Virus In Vitro and In Vivo

Viruses ◽  
2021 ◽  
Vol 13 (4) ◽  
pp. 548
Author(s):  
Kiramage Chathuranga ◽  
Asela Weerawardhana ◽  
Niranjan Dodantenna ◽  
Lakmal Ranathunga ◽  
Won-Kyung Cho ◽  
...  
Keyword(s):  
Respiratory Syncytial Virus ◽  
Antiviral Agent ◽  
Active Components ◽  
Sargassum Fusiforme ◽  
Antiviral Effects ◽  
Improve Life Expectancy ◽  
Rsv Infection ◽  
Syncytial Virus

Sargassum fusiforme, a plant used as a medicine and food, is regarded as a marine vegetable and health supplement to improve life expectancy. Here, we demonstrate that S. fusiforme extract (SFE) has antiviral effects against respiratory syncytial virus (RSV) in vitro and in vivo mouse model. Treatment of HEp2 cells with a non-cytotoxic concentration of SFE significantly reduced RSV replication, RSV-induced cell death, RSV gene transcription, RSV protein synthesis, and syncytium formation. Moreover, oral inoculation of SFE significantly improved RSV clearance from the lungs of BALB/c mice. Interestingly, the phenolic compounds eicosane, docosane, and tetracosane were identified as active components of SFE. Treatment with a non-cytotoxic concentration of these three components elicited similar antiviral effects against RSV infection as SFE in vitro. Together, these results suggest that SFE and its potential components are a promising natural antiviral agent candidate against RSV infection.

RESPIRATORY SYNCYTIAL VIRUS LUNG INFECTION IN INFANTS: IMMUNOREGULATORY ROLE OF INFECTED ALVEOLAR MACROPHAGES

PEDIATRICS ◽  
1995 ◽  
Vol 96 (2) ◽  
pp. 391-391
Author(s):  
Leon S. Greos
Keyword(s):  
Immune Response ◽  
Respiratory Syncytial Virus ◽  
Lung Injury ◽  
Alveolar Macrophages ◽  
Lung Infection ◽  
Local Immune Response ◽  
Rsv Infection ◽  
Syncytial Virus

Alveolar macrophages are infected by RSV in vivo and coexpress potent immunomodulatory molecules that potentially regulate local immune response or lung injury caused by RSV infection.

scholarly journals Lentiviral and AAV-mediated Expression of Palivizumab Offer protection against Respiratory Syncytial Virus infection

2021 ◽  
Author(s):  
Agata Antepowicz ◽  
Omar Habib ◽  
Freja Kirsebom ◽  
Cecilia Johansson ◽  
Deborah R. Gill ◽  
...  
Keyword(s):  
Respiratory Syncytial Virus ◽  
Vulnerable Populations ◽  
The Elderly ◽  
Complete Protection ◽  
Adeno Associated Virus ◽  
Common Cause ◽  
Immunodeficiency Virus ◽  
Rsv Infection ◽  
Syncytial Virus

Abstract Respiratory syncytial virus (RSV) infection is a common cause of hospitalisation in infants and the elderly. Palivizumab prophylaxis is the only approved treatment modality but is costly and only offered to select vulnerable populations. Here, we investigated gene delivery approaches via recombinant adeno-associated virus (rAAV2/8) and simian immunodeficiency virus (rSIV.F/HN) vectors to achieve sustained in vivo production of palivizumab in a murine model. Delivery of palivizumab-expressing vectors 28 days prior to RSV challenge resulted in complete protection from RSV-induced weight loss. This approach offers prophylaxis against RSV infection, allowing for wider use and reduction in treatment costs in vulnerable populations.

scholarly journals Exacerbation of Influenza A Virus Disease Severity by Respiratory Syncytial Virus Co-Infection in a Mouse Model

Viruses ◽  
2021 ◽  
Vol 13 (8) ◽  
pp. 1630 ◽  
Author(s):  
Junu A. George ◽  
Shaikha H. AlShamsi ◽  
Maryam H. Alhammadi ◽  
Ahmed R. Alsuwaidi
Keyword(s):  
T Cells ◽  
Respiratory Syncytial Virus ◽  
Influenza A Virus ◽  
Influenza A ◽  
Immune Cell ◽  
Virus Disease ◽  
Viral Loads ◽  
Syncytial Virus

Influenza A virus (IAV) and respiratory syncytial virus (RSV) are leading causes of childhood infections. RSV and influenza are competitive in vitro. In this study, the in vivo effects of RSV and IAV co-infection were investigated. Mice were intranasally inoculated with RSV, with IAV, or with both viruses (RSV+IAV and IAV+RSV) administered sequentially, 24 h apart. On days 3 and 7 post-infection, lung tissues were processed for viral loads and immune cell populations. Lung functions were also evaluated. Mortality was observed only in the IAV+RSV group (50% of mice did not survive beyond 7 days). On day 3, the viral loads in single-infected and co-infected mice were not significantly different. However, on day 7, the IAV titer was much higher in the IAV+RSV group, and the RSV viral load was reduced. CD4 T cells were reduced in all groups on day 7 except in single-infected mice. CD8 T cells were higher in all experimental groups except the RSV-alone group. Increased airway resistance and reduced thoracic compliance were demonstrated in both co-infected groups. This model indicates that, among all the infection types we studied, infection with IAV followed by RSV is associated with the highest IAV viral loads and the most morbidity and mortality.

scholarly journals Pathogenesis of Respiratory Syncytial Virus Infection in BALB/c Mice Differs Between Intratracheal and Intranasal Inoculation

Viruses ◽  
2019 ◽  
Vol 11 (6) ◽  
pp. 508 ◽  
Author(s):  
Elisabeth A. van Erp ◽  
Anke J. Lakerveld ◽  
H. Lie Mulder ◽  
Willem Luytjes ◽  
Gerben Ferwerda ◽  
...  
Keyword(s):  
Respiratory Syncytial Virus ◽  
Animal Models ◽  
Antiviral Agents ◽  
Mouse Strains ◽  
Immunological Parameters ◽  
Intranasal Inoculation ◽  
Rsv Infection ◽  
Syncytial Virus ◽  
Tract Disease

Human respiratory syncytial virus (RSV) is a major cause of severe lower respiratory tract disease requiring hospitalization in infants. There are no market-approved vaccines or antiviral agents available, but a growing number of vaccines and therapeutics are in (pre)clinical stages of development. Reliable animal models are crucial to evaluate new vaccine concepts, but in vivo RSV research is hampered by the lack of well-characterized animal models that faithfully mimic the pathogenesis of RSV infection in humans. Mice are frequently used in RSV infection and vaccination studies. However, differences in the use of mouse strains, RSV subtypes, and methodology often lead to divergent study outcomes. To our knowledge, a comparison between different RSV inoculation methods in mice has not been described in the literature, even though multiple methods are being used across different studies. In this study, we evaluated various pathological and immunological parameters in BALB/c mice after intratracheal or intranasal inoculation with RSV-A2. Our study reveals that intranasal inoculation induces robust pathology and inflammation, whereas this is not the case for intratracheal inoculation. As immunopathology is an important characteristic of RSV disease in infants, these data suggest that in mice intranasal inoculation is a more appropriate method to study RSV infection than intratracheal inoculation. These findings will contribute to the rational experimental design of future in vivo RSV experiments.

scholarly journals Eosinophils contribute to innate antiviral immunity and promote clearance of respiratory syncytial virus

Blood ◽  
2007 ◽  
Vol 110 (5) ◽  
pp. 1578-1586 ◽  
Author(s):  
Simon Phipps ◽  
Chuan En Lam ◽  
Suresh Mahalingam ◽  
Matthew Newhouse ◽  
Ruben Ramirez ◽  
...  
Keyword(s):  
Respiratory Syncytial Virus ◽  
Host Defense ◽  
No Production ◽  
Wild Type ◽  
Interleukin 5 ◽  
Virus Clearance ◽  
Lung Dysfunction ◽  
Rsv Infection ◽  
Syncytial Virus

AbstractEosinophils are recruited to the lungs in response to respiratory syncytial virus (RSV) infection; however, their role in promoting antiviral host defense remains unclear. Here, we demonstrate that eosinophils express TLRs that recognize viral nucleic acids, are activated and degranulate after single-stranded RNA (ssRNA) stimulation of the TLR-7–MyD88 pathway, and provide host defense against RSV that is MyD88 dependent. In contrast to wild-type mice, virus clearance from lung tissue was more rapid in hypereosinophilic (interleukin-5 transgenic) mice. Transfer of wild-type but not MyD88-deficient eosinophils to the lungs of RSV-infected wild-type mice accelerated virus clearance and inhibited the development of airways hyperreactivity. Similar responses were observed when infected recipient mice were MyD88 deficient. Eosinophils isolated from infected hypereosinophilic MyD88-sufficient but not MyD88-deficient mice expressed greater amounts of IFN regulatory factor (IRF)–7 and eosinophil-associated ribonucleases EAR-1 and EAR-2. Hypereosinophilia in the airways of infected mice also correlated with increased expression of IRF-7, IFN-β, and NOS-2, and inhibition of NO production with the NOS-2 inhibitor L-NMA partially reversed the accelerated virus clearance promoted by eosinophils. Collectively, our results demonstrate that eosinophils can protect against RSV in vivo, as they promote virus clearance and may thus limit virus-induced lung dysfunction.

scholarly journals Targeting the Respiratory Syncytial Virus N0-P Complex with Constrained α-Helical Peptides in Cells and Mice

2020 ◽  
Vol 64 (10) ◽  
Author(s):  
Marie Galloux ◽  
Nadège Gsponer ◽  
Vanessa Gaillard ◽  
Brice Fenner ◽  
Thibaut Larcher ◽  
...  
Keyword(s):  
Respiratory Syncytial Virus ◽  
Small Molecules ◽  
Mechanisms Of Action ◽  
Rsv Infection ◽  
Macrocyclic Peptides ◽  
Escape Mutants ◽  
Severe Respiratory Infection ◽  
Syncytial Virus

ABSTRACT Respiratory syncytial virus (RSV) is the main cause of severe respiratory infection in young children worldwide, and no therapies have been approved for the treatment of RSV infection. Data from recent clinical trials of fusion or L polymerase inhibitors for the treatment of RSV-infected patients revealed the emergence of escape mutants, highlighting the need for the discovery of inhibitors with novel mechanisms of action. Here we describe stapled peptides derived from the N terminus of the phosphoprotein (P) that act as replication inhibitors. We demonstrate that these peptides inhibit RSV replication in vitro and in vivo by preventing the formation of the N0-P complex. The present strategy provides a novel means of targeting RSV replication with constrained macrocyclic peptides or small molecules and is broadly applicable to other viruses of the Mononegavirales order.

scholarly journals Role of G2-S16 Polyanionic Carbosilane Dendrimer in the Prevention of Respiratory Syncytial Virus Infection In Vitro and In Vivo in Mice

Polymers ◽  
2021 ◽  
Vol 13 (13) ◽  
pp. 2141
Author(s):  
Ignacio Rodriguez-Izquierdo ◽  
Rafael Ceña-Diez ◽  
Maria Jesús Serramia ◽  
Rosa Rodriguez-Fernández ◽  
Isidoro Martínez ◽  
...  
Keyword(s):  
Respiratory Syncytial Virus ◽  
Cell Surface ◽  
Host Cells ◽  
Carbosilane Dendrimer ◽  
Rsv Infection ◽  
Host Cell Surface ◽  
Syncytial Virus

The respiratory syncytial virus (RSV) causes respiratory infection and bronchiolitis, requiring hospitalization mainly in infants. The interaction between RSV, envelope glycoproteins G and F, and cell surface heparan sulfate proteoglycans (HSPG) is required for binding and entry into the host cells. A G2-S16 polyanionic carbosilane dendrimer was identified as a possible RSV inhibitor. We speculated that the G2-S16 dendrimer adheres to the host cell-surface HSPG, acts through binding to HS receptors, and prevents further RSV infection. The G2-S16 dendrimer was non-toxic when applied intranasally to Balb/c mice, and interestingly enough, this G2-S16 dendrimer inhibits 85% RSV. Therefore, our G2-S16 dendrimer could be a candidate for developing a new possible therapy against RSV infection.

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