Intranasal and intrapulmonary vaccination with an M protein-deficient respiratory syncytial virus (RSV) vaccine improves clinical signs and reduces viral replication in infant baboons after an RSV challenge infection

The mechanism of respiratory syncytial virus (RSV)-induced inflammation in the airways of infants and children is not fully understood. We hypothesized that RSV directly induces interleukin (IL)-8 gene expression in airway epithelial cells, independent of IL-1 beta and tumor necrosis factor-alpha (TNF-alpha) production. Exposure of A549 cells (an airway epithelial cell line) to RSV resulted in increased IL-8 mRNA expression and IL-8 protein release from the cells as early as 2 h after treatment. Neither IL-1 beta nor TNF-alpha (mRNA or protein) were detected. Viral replication was not necessary for the effects of RSV on IL-8 mRNA expression and protein release early in the infectious process. However, sustained levels of increased IL-8 production required RSV replication. A dose-response relationship was observed between the multiplicity of infection and IL-8 production with both active and nonreplicative RSV at the 2-h time point. Both active RSV and nonreplicative RSV increased the transcriptional activity of the 1.6-kb 5' flanking region of the IL-8 gene. Neither active RSV nor nonreplicative RSV increased the stability of the IL-8 mRNA in A549 cells. We conclude that RSV increases IL-8 gene expression in A549 cells in a biphasic pattern independent of viral replication early (2 h) but dependent on viral replication late (24 h).

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Respiratory syncytial virus-A dynamics and the effects of lumicitabine, a nucleoside viral replication inhibitor, in experimentally infected humans

Journal of Antimicrobial Chemotherapy ◽

10.1093/jac/dky415 ◽

2018 ◽

Vol 74 (2) ◽

pp. 442-452 ◽

Cited By ~ 3

Author(s):

Kashyap Patel ◽

Carl M Kirkpatrick ◽

Keith A Nieforth ◽

Sushmita Chanda ◽

Qingling Zhang ◽

...

Keyword(s):

Respiratory Syncytial Virus ◽

Viral Replication ◽

Replication Inhibitor ◽

Syncytial Virus

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Supplementing a Saccharomyces cerevisiae fermentation product modulates innate immune function and ameliorates bovine respiratory syncytial virus infection in neonatal calves

Journal of Animal Science ◽

10.1093/jas/skaa252 ◽

2020 ◽

Vol 98 (8) ◽

Author(s):

Asmaa H A Mahmoud ◽

Jamison R Slate ◽

Suyeon Hong ◽

Ilkyu Yoon ◽

Jodi L McGill

Keyword(s):

Saccharomyces Cerevisiae ◽

Respiratory Syncytial Virus ◽

Immune Function ◽

Clinical Signs ◽

Bovine Respiratory Syncytial Virus ◽

Dairy Calves ◽

Lung Pathology ◽

Fermentation Products ◽

Supplementation Period ◽

Syncytial Virus

Abstract The objectives of this study were to determine the effects of oral supplementation with Saccharomyces cerevisiae fermentation products (SCFP; SmartCare and NutriTek; Diamond V, Cedar Rapids, IA) on immune function and bovine respiratory syncytial virus (BRSV) infection in preweaned dairy calves. Twenty-four Holstein × Angus, 1- to 2-d-old calves (38.46 ± 0.91 kg initial body weight [BW]) were assigned two treatment groups: control or SCFP treated, milk replacer with 1 g/d SCFP (SmartCare) and calf starter top-dressed with 5 g/d SCFP (NutriTek). The study consisted of one 31-d period. On days 19 to 21 of the supplementation period, calves were challenged via aerosol inoculation with BRSV strain 375. Calves were monitored twice daily for clinical signs, including rectal temperature, cough, nasal and ocular discharge, respiration effort, and lung auscultation. Calves were euthanized on day 10 postinfection (days 29 to 31 of the supplementation period) to evaluate gross lung pathology and pathogen load. Supplementation with SCFP did not affect BW (P = 0.762) or average daily gain (P = 0.750), percentages of circulating white blood cells (P < 0.05), phagocytic (P = 0.427 for neutrophils and P = 0.460 for monocytes) or respiratory burst (P = 0.119 for neutrophils and P = 0.414 for monocytes) activity by circulating leukocytes either before or following BRSV infection, or serum cortisol concentrations (P = 0.321) after BRSV infection. Calves receiving SCFP had reduced clinical disease scores compared with control calves (P = 0.030), reduced airway neutrophil recruitment (P < 0.002), reduced lung pathology (P = 0.031), and a reduced incidence of secondary bacterial infection. Calves receiving SCFP shed reduced virus compared with control calves (P = 0.049) and tended toward lower viral loads in the lungs (P = 0.051). Immune cells from the peripheral blood of SCFP-treated calves produced increased (P < 0.05) quantities of interleukin (IL)-6 and tumor necrosis factor-alpha in response to toll-like receptor stimulation, while cells from the bronchoalveolar lavage (BAL) of SCFP-treated calves secreted less (P < 0.05) proinflammatory cytokines in response to the same stimuli. Treatment with SCFP had no effect on virus-specific T cell responses in the blood but resulted in reduced (P = 0.045) virus-specific IL-17 secretion by T cells in the BAL. Supplementing with SCFP modulates both systemic and mucosal immune responses and may improve the outcome of an acute respiratory viral infection in preweaned dairy calves.

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The Interferon Type I/III Response to Respiratory Syncytial Virus Infection in Airway Epithelial Cells Can Be Attenuated or Amplified by Antiviral Treatment

Journal of Virology ◽

10.1128/jvi.02417-15 ◽

2015 ◽

Vol 90 (4) ◽

pp. 1705-1717 ◽

Cited By ~ 6

Author(s):

K. M. McCutcheon ◽

R. Jordan ◽

M. E. Mawhorter ◽

S. L. Noton ◽

J. G. Powers ◽

...

Keyword(s):

Life Cycle ◽

Respiratory Syncytial Virus ◽

Epithelial Cells ◽

Viral Replication ◽

Airway Epithelial Cells ◽

Therapeutic Interventions ◽

Airway Epithelial ◽

Antiviral Activities ◽

Syncytial Virus ◽

Interferon Responses

ABSTRACTHuman respiratory syncytial virus (RSV) is a single-stranded RNA virus that causes acute, and occasionally fatal, lower respiratory illness in young infants, the elderly, and immunocompromised patients. Therapeutic interventions able to cut short viral replication and quickly return the airways to normal function are needed. An understanding of antiviral activities and their effects on host defense mechanisms is important for the design of safe and effective therapy. We targeted functionally and temporally distinct steps within the viral life cycle using small-molecule RSV inhibitors and studied their antiviral activities and their effects on innate interferon responses of airway epithelial cellsin vitro. Antivirals acting upstream of RSV polymerase activity (i.e., compounds targeting the fusion protein or the nucleoprotein) reduced viral load immediately postinfection and partially attenuated interferon responses. In contrast, antivirals directed to the RSV polymerase demonstrated activity throughout the viral replication cycle and specifically modulated the RIG-I/mitochondrial antiviral signaling protein (MAVS)/TBK1/IRF3/interferon-stimulated gene (ISG) axis, causing either an upregulation or a downregulation of interferon responses, depending on the mechanism of polymerase inhibition. Notably, polymerase inhibition leading to the accumulation of abortive RNA products correlated with the amplification of interferon-stimulated genes to up to 10 times above normal infection levels. Understanding how antiviral activities and their modulation of innate immunity may affect recovery from RSV infection will help guide the development of safe and effective therapies.IMPORTANCERSV circulates seasonally, causing acute lower respiratory disease. Therapeutic interventions with efficacy throughout the viral replication cycle, rapid viral clearance, and prevention of potentially harmful inflammatory responses are desirable. Compounds targeting the RSV polymerase inhibited virus replication late in the viral life cycle and, depending on the functional domain targeted, either attenuated or amplified RIG-I and downstream interferon pathways in infected cells. These data will help guide the development of safe and effective therapies by providing new molecular evidence that the mechanism of inhibition by an antiviral compound can directly impact innate antiviral immune responses in the airway epithelium.

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Prolonged viral replication and longitudinal viral dynamic differences among respiratory syncytial virus infected infants

Pediatric Research ◽

10.1038/pr.2017.173 ◽

2017 ◽

Vol 82 (5) ◽

pp. 872-880 ◽

Cited By ~ 12

Author(s):

Monica E Brint ◽

Joshua M Hughes ◽

Aditya Shah ◽

Chelsea R Miller ◽

Lisa G Harrison ◽

...

Keyword(s):

Respiratory Syncytial Virus ◽

Viral Replication ◽

Viral Dynamic ◽

Syncytial Virus

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Respiratory Syncytial Virus–Induced Chemokine Production: Linking Viral Replication to Chemokine Production In Vitro and In Vivo

The Journal of Infectious Diseases ◽

10.1086/382958 ◽

2004 ◽

Vol 189 (8) ◽

pp. 1419-1430 ◽

Cited By ~ 125

Author(s):

Allison L. Miller ◽

Terry L. Bowlin ◽

Nicholas W. Lukacs

Keyword(s):

Respiratory Syncytial Virus ◽

Viral Replication ◽

Chemokine Production ◽

Syncytial Virus

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Experimental Bovine Respiratory Tract Disease with Haemophilus somnus

Veterinary Pathology ◽

10.1177/030098588802500204 ◽

1988 ◽

Vol 25 (2) ◽

pp. 124-130 ◽

Cited By ~ 21

Author(s):

L. N. D. Potgieter ◽

R. G. Helman ◽

W. Greene ◽

M. A. Breider ◽

E. T. Thurber ◽

...

Keyword(s):

Respiratory Syncytial Virus ◽

Respiratory Tract ◽

Disease Control ◽

Clinical Signs ◽

Bovine Respiratory Syncytial Virus ◽

Respiratory Tract Disease ◽

Naturally Occurring ◽

Haemophilus Somnus ◽

Syncytial Virus ◽

Tract Disease

Eight calves were inoculated into the bronchus with H. somnus. Thirteen calves were inoculated with bovine respiratory syncytial virus (BRSV) and 8 days later with H. somnus. All calves developed necrotizing, suppurative, lobular bronchopneumonia and pleuritis. Clinical signs of disease and pneumonic lesions were significantly more severe in calves that were sequentially inoculated with BRSV followed by H. somnus. Pneumonic lesions in the inoculated calves were similar to those described for naturally occurring H. somnus-associated respiratory tract disease. Control calves inoculated with BRSV alone or sham-inoculated with medium did not develop clinical signs of respiratory tract disease. The BRSV-inoculated control calves developed minimal pneumonic lesions.

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Host Transcription Profiles upon Primary Respiratory Syncytial Virus Infection

Journal of Virology ◽

10.1128/jvi.02220-06 ◽

2007 ◽

Vol 81 (11) ◽

pp. 5958-5967 ◽

Cited By ~ 42

Author(s):

Riny Janssen ◽

Jeroen Pennings ◽

Hennie Hodemaekers ◽

Annemarie Buisman ◽

Marijke van Oosten ◽

...

Keyword(s):

Immune Response ◽

Respiratory Syncytial Virus ◽

Lymph Nodes ◽

Viral Replication ◽

Transcriptional Level ◽

Type I ◽

Lung Pathology ◽

Transcription Profiles ◽

Rsv Infection ◽

Syncytial Virus

ABSTRACT Respiratory syncytial virus (RSV) is a common cause of severe lower respiratory tract infection in children. Severe RSV disease is related to an inappropriate immune response to RSV resulting in enhanced lung pathology which is influenced by host genetic factors. To gain insight into the early pathways of the pathogenesis of and immune response to RSV infection, we determined the transcription profiles of lungs and lymph nodes on days 1 and 3 after infection of mice. Primary RSV infection resulted in a rapid but transient innate, proinflammatory response, as exemplified by the induction of a large number of type I interferon-regulated genes and chemokine genes, genes involved in inflammation, and genes involved in antigen processing. Interestingly, this response is much stronger on day 1 than on day 3 after infection, indicating that the strong transcriptional response in the lung precedes the peak of viral replication. Surprisingly, the set of down-regulated genes was small and none of these genes displayed strong down-regulation. Responses in the lung-draining lymph nodes were much less prominent than lung responses and are suggestive of NK cell activation. Our data indicate that at time points prior to the peak of viral replication and influx of inflammatory cells, the local lung response, measured at the transcriptional level, has already dampened down. The processes and pathways induced shortly after RSV infection can now be used for the selection of candidate genes for human genetic studies of children with severe RSV infection.

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Human respiratory syncytial virus methyl transferase: a potential antiviral target?

F1000Research ◽

10.12688/f1000research.18800.1 ◽

2019 ◽

Vol 8 ◽

pp. 750

Author(s):

Raj Kalkeri ◽

Govinda Bhisetti ◽

Nagraj Mani

Keyword(s):

Respiratory Syncytial Virus ◽

Viral Replication ◽

Sequence Similarity ◽

Human Respiratory Syncytial Virus ◽

Methyl Transferase ◽

Mtase Activity ◽

Literature Reviews ◽

Host Innate Immune Response ◽

Syncytial Virus

Human respiratory syncytial virus (HRSV) causes bronchiolitis and pneumonia. The role of methyltransferase (MTase) activity of HRSV polymerase in viral replication is unknown. Literature reviews of similar viral MTases and homology- modeling of RSV MTase bound to GTP and S-adenosylmethionine (SAM) have shown sequence similarity and the conserved catalytic residues (K-D-K-E) and the SAM-binding (GXGXG) domain. Combined with the recent reports of the importance of 2’O methylation of viral RNAs in the host innate immune response evasion, and its proposed role in viral replication, HRSV MTase holds promise as a potential antiviral target. Further biological validation of HRSV MTase could facilitate the discovery of novel HRSV antivirals targeting MTase enzyme activity.

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M Protein-Deficient Respiratory Syncytial Virus (RSV) Vaccine Protects Infant Baboons Against RSV Challenge

Open Forum Infectious Diseases ◽

10.1093/ofid/ofx163.755 ◽

2017 ◽

Vol 4 (suppl_1) ◽

pp. S321-S321

Author(s):

Robert C Welliver ◽

Antonius Oomens ◽

Roman Wolf ◽

James Papin ◽

Vadim Ivanov ◽

...

Keyword(s):

Viral Replication ◽

Neutralizing Antibody ◽

Airway Disease ◽

Antibody Responses ◽

M Protein ◽

Arterial Oxygen ◽

Human Infants ◽

Rsv Infection ◽

Syncytial Virus ◽

Lymphocyte Responses

Abstract Background RSV bronchiolitis is the most common cause of hospitalization of infants in the US, and may lead to the development of long-term airway disease. Inactivated vaccines may lead to enhanced disease, while replicating vaccines have caused unacceptable degrees of illness, and may revert back to wild type. We developed an RSV vaccine lacking the gene for the M protein (Mnull RSV). The M protein is responsible for reassembly of the virus after it infects cells and expresses its proteins. Infant baboons vaccinated intranasally (IN) with Mnull RSV develop serum neutralizing antibody (NA) responses, but the virus does not replicate. Methods 2-week-old baboons (n = 12) were primed IN with 107 vaccine units of Mnull RSV or a control preparation, and a similar booster dose was given 4 weeks later. Mnull RSV vaccination did not cause tachypnea, airway inflammation or other signs of illness when compared with sham-vaccinated controls. Two weeks after boosting, all infants were challenged intratracheally with human RSV A2. We continuously monitored respiratory rates and levels of overall activity. On various days following challenge, we obtained BAL fluids for leukocyte counts and degree of virus replication, and evaluated alveolar-arterial oxygen gradients (A-a O2). Results Vaccinated animals (vs. unvaccinated controls) had lower respiratory rates (P = 0.0014), improved A-a O2 (P = 0.0063) and reduced viral replication (P = 0.0014). Activity scores were higher in vaccine recipients than in unvaccinated animals. Vaccine recipients also were primed for earlier serum and secretory neutralizing antibody responses, and greater airway lymphocyte responses. Airway lymphocyte numbers (but not antibody responses) were associated with lower respiratory rates and reduced viral replication (P < 0.01). Conclusion Vaccination intranasally with Mnull RSV protected infant baboons against an RSV challenge without causing respiratory disease or enhanced illness, and is a promising candidate for use in human infants. Lymphocyte responses to vaccination may play an equal or greater role in protection against RSV infection than antibody responses. Disclosures All authors: No reported disclosures.

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