In Vitro and In Vivo Fitness of Respiratory Syncytial Virus Monoclonal Antibody Escape Mutants

ABSTRACT Respiratory syncytial virus (RSV) is the only infectious disease for which a monoclonal antibody (MAb) is used in humans. Palivizumab (PZ) is a humanized murine MAb to the F protein of RSV. PZ-resistant viruses appear after in vitro and in vivo growth of RSV in the presence of PZ. Fitness for replication could be a determinant of the likelihood of dissemination of resistant viruses. We assessed the fitness of two PZ-resistant viruses (F212 and MP4). F212 grew less well in cell culture than the parent A2 virus and was predicted to be less fit than A2. Equal amounts of F212 and A2 were mixed and passaged in cell culture. F212 disappeared from the viral population, indicating it was less fit than the A2 virus. The MP4 virus grew as well as A2 in culture and in cotton rats. A2/MP4 virus input ratios of 1:1, 10:1, 100:1, and 1,000:1 were compared in competitive replication. For all input ratios except 1,000:1, the MP4 virus became dominant, supplanting the A2 virus. The MP4 virus also dominated the A2 virus during growth in cotton rats. Thus, the mutant MP4 virus was more fit than A2 virus in both in vitro and in vivo competitive replication. Whether this fitness difference was due to the identified nucleotide substitutions in the F gene or to mutations elsewhere in the genome is unknown. Understanding the mechanisms by which mutant virus fitness increased or decreased could prove useful for consideration in attenuated vaccine design efforts.

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Monoclonal antibody based in vitro potency assay as a predictor of antigenic integrity and in vivo immunogenicity of a Respiratory Syncytial Virus post-fusion F-protein based vaccine

Vaccine ◽

10.1016/j.vaccine.2018.01.055 ◽

2018 ◽

Vol 36 (12) ◽

pp. 1673-1680

Author(s):

Matieyendou Didier Djagbare ◽

Li Yu ◽

Arun Parupudi ◽

Jenny Sun ◽

Melissa L. Coughlin ◽

...

Keyword(s):

Monoclonal Antibody ◽

Respiratory Syncytial Virus ◽

Potency Assay ◽

F Protein ◽

Syncytial Virus

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RFI-641, a Potent Respiratory Syncytial Virus Inhibitor

Antimicrobial Agents and Chemotherapy ◽

10.1128/aac.46.3.841-847.2002 ◽

2002 ◽

Vol 46 (3) ◽

pp. 841-847 ◽

Cited By ~ 48

Author(s):

Clayton C. Huntley ◽

William J. Weiss ◽

Anna Gazumyan ◽

Aron Buklan ◽

Boris Feld ◽

...

Keyword(s):

Respiratory Syncytial Virus ◽

Respiratory Tract Infections ◽

Syncytium Formation ◽

Therapeutic Window ◽

Monkey Model ◽

Cotton Rats ◽

Syncytial Virus ◽

Tract Infections

ABSTRACT Human respiratory syncytial virus (RSV), a paramyxovirus, is a major cause of acute upper and lower respiratory tract infections in infants, young children, and adults. RFI-641 is a novel anti-RSV agent with potent in vitro and in vivo activity. RFI-641 is active against both RSV type A and B strains. The viral specificity and the large therapeutic window of RFI-641 (>100-fold) indicate that the antiviral activity of the compound is not due to adverse effects on normal cells. The potent in vitro activity of RFI-641 can be translated to efficacy in vivo: RFI-641 is efficacious when administered prophylactically by the intranasal route in mice, cotton rats, and African green monkeys. RFI-641 is also efficacious when administered therapeutically (24 h postinfection) in the monkey model. Mechanism of action studies indicate that RFI-641 blocks viral F protein-mediated fusion and cell syncytium formation.

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Development of a Humanized Monoclonal Antibody (MEDI‐493) with Potent In Vitro and In Vivo Activity against Respiratory Syncytial Virus

The Journal of Infectious Diseases ◽

10.1086/514115 ◽

1997 ◽

Vol 176 (5) ◽

pp. 1215-1224 ◽

Cited By ~ 406

Author(s):

Syd Johnson ◽

Cynthia Oliver ◽

Gregory A. Prince ◽

Val G. Hemming ◽

David S. Pfarr ◽

...

Keyword(s):

Monoclonal Antibody ◽

Respiratory Syncytial Virus ◽

Humanized Monoclonal Antibody ◽

Syncytial Virus

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Cloning of the transmembrane glycoproteins G and F from a Brazilian isolate of bovine respiratory syncytial virus in a prokaryotic system

Arquivo Brasileiro de Medicina Veterinária e Zootecnia ◽

10.1590/s0102-09352011000300003 ◽

2011 ◽

Vol 63 (3) ◽

pp. 552-558

Author(s):

L.H.A. Silva ◽

K.C. Cardoso ◽

M.J. Silva ◽

F.R. Spilki ◽

C.W. Arns

Keyword(s):

Respiratory Syncytial Virus ◽

Biological Effects ◽

Bovine Respiratory Syncytial Virus ◽

Brazilian Isolate ◽

Nucleotide Substitutions ◽

Respiratory Syncytial Viruses ◽

Syncytial Virus

The aim of this work was the cloning of those transmembrane glycoproteins G and F from an isolate bovine respiratory syncytial viruses (BRSV) - a Brazilian isolate of BRSV, named BRSV-25-BR in previous studies, in a prokaryotic system to proceed the sequencing of larger genomic fragments. The nucleotide substitutions were confirmed and these clones may also be used in further studies regarding the biological effects of those proteins in vitro and in vivo.

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

Virologica Sinica ◽

10.1007/s12250-021-00345-3 ◽

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.

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

Viruses ◽

10.3390/v13040548 ◽

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.

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Recombinant subtype A and B human respiratory syncytial virus clinical isolates co-infect the respiratory tract of cotton rats

Journal of General Virology ◽

10.1099/jgv.0.001471 ◽

2020 ◽

Vol 101 (10) ◽

pp. 1056-1068

Author(s):

Linda J. Rennick ◽

Sham Nambulli ◽

Ken Lemon ◽

Grace Y. Olinger ◽

Nicholas A. Crossland ◽

...

Keyword(s):

Respiratory Syncytial Virus ◽

Respiratory Tract ◽

Reverse Genetics ◽

Fluorescent Protein ◽

Human Respiratory Syncytial Virus ◽

Subtype B ◽

Cotton Rats ◽

Syncytial Virus ◽

Subtype A

Human respiratory syncytial virus (HRSV) is an important respiratory pathogen causing a spectrum of illness, from common cold-like symptoms, to bronchiolitis and pneumonia requiring hospitalization in infants, the immunocompromised and the elderly. HRSV exists as two antigenic subtypes, A and B, which typically cycle biannually in separate seasons. There are many unresolved questions in HRSV biology regarding the interactions and interplay of the two subtypes. Therefore, we generated a reverse genetics system for a subtype A HRSV from the 2011 season (A11) to complement our existing subtype B reverse genetics system. We obtained the sequence (HRSVA11) directly from an unpassaged clinical sample and generated the recombinant (r) HRSVA11. A version of the virus expressing enhanced green fluorescent protein (EGFP) from an additional transcription unit in the fifth (5) position of the genome, rHRSVA11EGFP(5), was also generated. rHRSVA11 and rHRSVA11EGFP(5) grew comparably in cell culture. To facilitate animal co-infection studies, we derivatized our subtype B clinical isolate using reverse genetics toexpress the red fluorescent protein (dTom)-expressing rHRSVB05dTom(5). These viruses were then used to study simultaneous in vivo co-infection of the respiratory tract. Following intranasal infection, both rHRSVA11EGFP(5) and rHRSVB05dTom(5) infected cotton rats targeting the same cell populations and demonstrating that co-infection occurs in vivo. The implications of this finding on viral evolution are important since it shows that inter-subtype cooperativity and/or competition is feasible in vivo during the natural course of the infection.

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

Viruses ◽

10.3390/v13081630 ◽

2021 ◽

Vol 13 (8) ◽

pp. 1630 ◽

Cited By ~ 1

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.

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Assessing Uncertainty in A2 Respiratory Syncytial Virus Viral Dynamics

Computational and Mathematical Methods in Medicine ◽

10.1155/2015/567589 ◽

2015 ◽

Vol 2015 ◽

pp. 1-9 ◽

Cited By ~ 15

Author(s):

Gilberto González-Parra ◽

Hana M. Dobrovolny

Keyword(s):

Respiratory Syncytial Virus ◽

Human Subjects ◽

Respiratory Illness ◽

The United States ◽

Viral Kinetics ◽

Phase Duration ◽

Syncytial Virus ◽

Parameter Values

Respiratory syncytial virus (RSV) is the most common cause of bronchiolitis and pneumonia in children younger than 1 year of age in the United States. Moreover, RSV is being recognized more often as a significant cause of respiratory illness in older adults. Although RSV has been studied both clinically and in vitro, a quantitative understanding of the infection dynamics is still lacking. In this paper, we study the effect of uncertainty in the main parameters of a viral kinetics model of RSV. We first characterize the RSV replication cycle and extract parameter values by fitting the mathematical model to in vivo data from eight human subjects. We then use Monte Carlo numerical simulations to determine how uncertainty in the parameter values will affect model predictions. We find that uncertainty in the infection rate, eclipse phase duration, and infectious lifespan most affect the predicted dynamics of RSV. This study provides the first estimate of in vivo RSV infection parameters, helping to quantify RSV dynamics. Our assessment of the effect of uncertainty will help guide future experimental design to obtain more precise parameter values.

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