20 results match your criteria titers pre-f

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RSV Specific Antibodies in Pregnant Women and Subsequent Risk of RSV Hospitalization in Young Infants.

J Infect Dis 2021 Jun 15. Epub 2021 Jun 15.

Helsinki University Hospital and University of Helsinki, Children's Hospital, Helsinki, Finland.

Background: The fusion (F) glycoprotein of respiratory syncytial virus (RSV) represents the major neutralizing antigen, and antibodies against the pre-F conformation have the most potent neutralizing activity. This study aimed to assess the correlation between maternal antibody (Ab) titers against the pre-F, post-F and G glycoproteins and the child's risk of developing severe RSV bronchiolitis early in infancy.

Methods: We identified previously healthy term infants less than 3 months of age hospitalized with RSV bronchiolitis from December 2015 to March 2016. Read More

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Level of maternal respiratory syncytial virus (RSV) F antibodies in hospitalized children and correlates of protection.

Int J Infect Dis 2021 Aug 10;109:56-62. Epub 2021 Jun 10.

Biomedical Research Center, Qatar University, Qatar; College of Health Sciences, Qatar University, Qatar. Electronic address:

Background: Respiratory syncytial virus (RSV) is a major cause of lower respiratory infection among children and no vaccine is available. The stabilized form of the fusion (F) protein - pre-F - is a leading vaccine candidate to target different populations, including pregnant women. This study aimed to determine the magnitude and nature of RSV-directed maternal antibodies (matAbs) in hospitalized children with RSV infection. Read More

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Prevention of Respiratory Syncytial Virus Infection in Healthy Adults by a Single Immunization of Ad26.RSV.preF in a Human Challenge Study.

J Infect Dis 2021 Jan 5. Epub 2021 Jan 5.

Janssen Vaccines & Prevention BV, Leiden, The Netherlands.

Background: Respiratory syncytial virus (RSV) is a significant cause of severe lower respiratory tract disease in children and older adults, but has no approved vaccine. This study assessed the potential of Ad26.RSV. Read More

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January 2021

A Parainfluenza Virus Vector Expressing the Respiratory Syncytial Virus (RSV) Prefusion F Protein Is More Effective than RSV for Boosting a Primary Immunization with RSV.

J Virol 2020 12 22;95(2). Epub 2020 Dec 22.

RNA Viruses Section, Laboratory of Infectious Diseases, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland, USA

Live-attenuated pediatric vaccines for intranasal administration are being developed for human respiratory syncytial virus (RSV), an important worldwide pediatric respiratory pathogen that lacks a licensed vaccine or suitable antiviral drug. We evaluated a prime-boost strategy in which primary immunization with RSV was boosted by secondary immunization with RSV or with a chimeric recombinant bovine/human parainfluenza virus type 3 (rB/HPIV3) vector expressing the RSV fusion F protein. The vector-expressed F protein had been engineered (DS-Cav1 mutations) for increased stability in the highly immunogenic prefusion (pre-F) conformation, with or without replacement of its transmembrane and cytoplasmic tail domains with their counterparts from bovine parainfluenza virus type 3 (BPIV3) F protein to direct incorporation into the vector virion for increased immunogenicity. Read More

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December 2020

Phase 1 Safety and Immunogenicity Study of a Respiratory Syncytial Virus Vaccine With an Adenovirus 26 Vector Encoding Prefusion F (Ad26.RSV.preF) in Adults Aged ≥60 Years.

J Infect Dis 2020 08;222(6):979-988

Janssen Vaccines & Prevention, Leiden, the Netherlands.

Background: Despite the high disease burden of respiratory syncytial virus (RSV) in older adults, there is no approved vaccine. We evaluated the experimental RSV vaccine, Ad26.RSV. Read More

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Development of a Stable Respiratory Syncytial Virus Pre-Fusion Protein Powder Suitable for a Core-Shell Implant with a Delayed Release in Mice: A Proof of Concept Study.

Pharmaceutics 2019 Oct 3;11(10). Epub 2019 Oct 3.

Department of Pharmaceutical Technology and Biopharmacy, University of Groningen, Antonius Deusinglaan 1, 9713 AV Groningen, The Netherlands.

Currently, there is an increasing interest to apply pre-fusion (pre-F) protein of respiratory syncytial virus (RSV) as antigen for the development of a subunit vaccine. A pre-F-containing powder would increase the flexibility regarding the route of administration. For instance, a pre-F-containing powder could be incorporated into a single-injection system releasing a primer, and after a lag time, a booster. Read More

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October 2019

Alternative Virus-Like Particle-Associated Prefusion F Proteins as Maternal Vaccines for Respiratory Syncytial Virus.

J Virol 2019 12 13;93(23). Epub 2019 Nov 13.

Department of Microbiology and Physiological Systems, University of Massachusetts Medical School, Worcester, Massachusetts, USA

Maternal vaccination may be the most effective and safest approach to the protection of infants from respiratory syncytial virus (RSV) infection, a severe acute lower respiratory tract disease in infants and young children worldwide. We previously compared five different virus-like particle (VLP)-associated, mutation-stabilized prefusion F (pre-F) proteins, including the prototype DS-Cav1 F VLPs. We showed that alternative versions of prefusion F proteins have different conformations and induce different populations of anti-F protein antibodies. Read More

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December 2019

The Optimal Concentration of Formaldehyde is Key to Stabilizing the Pre-Fusion Conformation of Respiratory Syncytial Virus Fusion Protein.

Viruses 2019 07 8;11(7). Epub 2019 Jul 8.

National Institute of Diagnostics and Vaccine Development in Infectious Diseases, School of Life Sciences, Xiamen University, Xiamen, Fujian 361005, China.

Background: To date, there is no licensed vaccine available to prevent respiratory syncytial virus (RSV) infection. The valuable pre-fusion conformation of the fusion protein (pre-F) is prone to lose high neutralizing antigenic sites. The goals of this study were to stabilize pre-F protein by fixatives and try to find the possibility of developing an inactivated RSV vaccine. Read More

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Effect of Previous Respiratory Syncytial Virus Infection on Murine Immune Responses to F and G Protein-Containing Virus-Like Particles.

J Virol 2019 05 17;93(9). Epub 2019 Apr 17.

Department of Microbiology and Physiological Systems Program in Immunology, University of Massachusetts Medical School, Worcester, Massachusetts, USA

Most individuals are infected with respiratory syncytial virus (RSV) by age two, but infection does not result in long-term protective immunity to subsequent infections. Previous RSV infection may, however, impact responses to an RSV vaccine. The goal of these studies was to explore the effect of previous RSV infection on murine antibody responses to RSV F and G protein-containing virus-like particles (VLP), comparing responses to those resulting from VLP immunization of RSV-naive animals. Read More

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Inferior immunogenicity and efficacy of respiratory syncytial virus fusion protein-based subunit vaccine candidates in aged versus young mice.

PLoS One 2017 28;12(11):e0188708. Epub 2017 Nov 28.

Department of Infectious Diseases/Vaccines, MedImmune, Gaithersburg, Maryland, United States of America.

Respiratory syncytial virus (RSV) is recognized as an important cause of lower and upper respiratory tract infections in older adults, and a successful vaccine would substantially lower morbidity and mortality in this age group. Recently, two vaccine candidates based on soluble purified glycoprotein F (RSV F), either alone or adjuvanted with glucopyranosyl lipid A formulated in a stable emulsion (GLA-SE), failed to reach their primary endpoints in clinical efficacy studies, despite demonstrating the desired immunogenicity profile and efficacy in young rodent models. Here, one of the RSV F vaccine candidates (post-fusion conformation, RSV post-F), and a stabilized pre-fusion form of RSV F (RSV pre-F, DS-Cav1) were evaluated in aged BALB/c mice. Read More

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December 2017

Adjuvants and the vaccine response to the DS-Cav1-stabilized fusion glycoprotein of respiratory syncytial virus.

PLoS One 2017 26;12(10):e0186854. Epub 2017 Oct 26.

Vaccine Research Center, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland, United States of America.

Appropriate adjuvant selection may be essential to optimize the potency and to tailor the immune response of subunit vaccines. To induce protective responses against respiratory syncytial virus (RSV)-a highly prevalent childhood pathogen without a licensed vaccine-we previously engineered a pre-fusion-stabilized trimeric RSV F (pre-F) "DS-Cav1" immunogen, which induced high titer RSV-neutralizing antibodies, in mice and non-human primates, when formulated with adjuvants Poly (I:C) and Poly (IC:LC), respectively. To assess the impact of different adjuvants, here we formulated RSV F DS-Cav1 with multiple adjuvants and assessed immune responses. Read More

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December 2017

Attenuated Human Parainfluenza Virus Type 1 Expressing the Respiratory Syncytial Virus (RSV) Fusion (F) Glycoprotein from an Added Gene: Effects of Prefusion Stabilization and Packaging of RSV F.

J Virol 2017 11 27;91(22). Epub 2017 Oct 27.

RNA Viruses Section, Laboratory of Infectious Diseases, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland, USA

Human respiratory syncytial virus (RSV) is the most prevalent worldwide cause of severe respiratory tract infection in infants and young children. Human parainfluenza virus type 1 (HPIV1) also causes severe pediatric respiratory illness, especially croup. Both viruses lack vaccines. Read More

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November 2017

The importance of RSV F protein conformation in VLPs in stimulation of neutralizing antibody titers in mice previously infected with RSV.

Hum Vaccin Immunother 2017 12 12;13(12):2814-2823. Epub 2017 Jun 12.

a Department of Microbiology and Physiological Systems, Sherman Center , University of Massachusetts Medical School , Worcester , MA , USA.

Respiratory syncytial virus (RSV) is a significant respiratory pathogen but no vaccine is available. RSV infections present 2 major, unique problems. First, humans can experience repeated infections caused by the same virus sero-group indicating that protective memory responses to RSV infection are defective. Read More

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December 2017

Improved Prefusion Stability, Optimized Codon Usage, and Augmented Virion Packaging Enhance the Immunogenicity of Respiratory Syncytial Virus Fusion Protein in a Vectored-Vaccine Candidate.

J Virol 2017 08 12;91(15). Epub 2017 Jul 12.

RNA Viruses Section, Laboratory of Infectious Diseases, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland, USA

Respiratory syncytial virus (RSV) is the most important viral agent of severe pediatric respiratory tract disease worldwide, but it lacks a licensed vaccine or suitable antiviral drug. A live attenuated chimeric bovine/human parainfluenza virus type 3 (rB/HPIV3) was developed previously as a vector expressing RSV fusion (F) protein to confer bivalent protection against RSV and HPIV3. In a previous clinical trial in virus-naive children, rB/HPIV3 was well tolerated but the immunogenicity of wild-type RSV F was unsatisfactory. Read More

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Discovery of a Prefusion Respiratory Syncytial Virus F-Specific Monoclonal Antibody That Provides Greater Protection than the Murine Precursor of Palivizumab.

J Virol 2017 08 12;91(15). Epub 2017 Jul 12.

State Key Laboratory of Molecular Vaccinology and Molecular Diagnostics, School of Public Health, Xiamen University, Xiamen, Fujian, People's Republic of China

Palivizumab, a humanized murine monoclonal antibody that recognizes antigenic site II on both the prefusion (pre-F) and postfusion (post-F) conformations of the respiratory syncytial virus (RSV) F glycoprotein, is the only prophylactic agent approved for use for the treatment of RSV infection. However, its relatively low neutralizing potency and high cost have limited its use to a restricted population of infants at high risk of severe disease. Previously, we isolated a high-potency neutralizing antibody, 5C4, that specifically recognizes antigenic site Ø at the apex of the pre-F protein trimer. Read More

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Immunization with Low Doses of Recombinant Postfusion or Prefusion Respiratory Syncytial Virus F Primes for Vaccine-Enhanced Disease in the Cotton Rat Model Independently of the Presence of a Th1-Biasing (GLA-SE) or Th2-Biasing (Alum) Adjuvant.

J Virol 2017 04 29;91(8). Epub 2017 Mar 29.

Department of Infectious Disease/Vaccines, Medimmune, Gaithersburg, Maryland, USA.

Respiratory syncytial virus (RSV) infection of children previously immunized with a nonlive, formalin-inactivated (FI)-RSV vaccine has been associated with serious enhanced respiratory disease (ERD). Consequently, detailed studies of potential ERD are a critical step in the development of nonlive RSV vaccines targeting RSV-naive children and infants. The fusion glycoprotein (F) of RSV in either its postfusion (post-F) or prefusion (pre-F) conformation is a target for neutralizing antibodies and therefore an attractive antigen candidate for a pediatric RSV subunit vaccine. Read More

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Packaging and Prefusion Stabilization Separately and Additively Increase the Quantity and Quality of Respiratory Syncytial Virus (RSV)-Neutralizing Antibodies Induced by an RSV Fusion Protein Expressed by a Parainfluenza Virus Vector.

J Virol 2016 Nov 14;90(21):10022-10038. Epub 2016 Oct 14.

RNA Viruses Section, Laboratory of Infectious Diseases, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland, USA

Human respiratory syncytial virus (RSV) and human parainfluenza virus type 3 (HPIV3) are major pediatric respiratory pathogens that lack vaccines. A chimeric bovine/human PIV3 (rB/HPIV3) virus expressing the unmodified, wild-type (wt) RSV fusion (F) protein from an added gene was previously evaluated in seronegative children as a bivalent intranasal RSV/HPIV3 vaccine, and it was well tolerated but insufficiently immunogenic for RSV F. We recently showed that rB/HPIV3 expressing a partially stabilized prefusion form (pre-F) of RSV F efficiently induced "high-quality" RSV-neutralizing antibodies, defined as antibodies that neutralize RSV in vitro without added complement (B. Read More

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November 2016

Structure-Based Design of Head-Only Fusion Glycoprotein Immunogens for Respiratory Syncytial Virus.

PLoS One 2016 27;11(7):e0159709. Epub 2016 Jul 27.

Vaccine Research Center, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland, 20892, United States of America.

Respiratory syncytial virus (RSV) is a significant cause of severe respiratory illness worldwide, particularly in infants, young children, and the elderly. Although no licensed vaccine is currently available, an engineered version of the metastable RSV fusion (F) surface glycoprotein-stabilized in the pre-fusion (pre-F) conformation by "DS-Cav1" mutations-elicits high titer RSV-neutralizing responses. Moreover, pre-F-specific antibodies, often against the neutralization-sensitive antigenic site Ø in the membrane-distal head region of trimeric F glycoprotein, comprise a substantial portion of the human response to natural RSV infection. Read More

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Cotton rat immune responses to virus-like particles containing the pre-fusion form of respiratory syncytial virus fusion protein.

J Transl Med 2015 Nov 5;13:350. Epub 2015 Nov 5.

Department of Microbiology and Physiological Systems, University of Massachusetts Medical School, Worcester, MA, 01655, USA.

Background: Virus-like particles (VLPs) based on Newcastle disease virus (NDV) core proteins, M and NP, and containing two chimera proteins, F/F and H/G, composed of the respiratory syncytial virus (RSV) fusion protein (F) and glycoprotein (G) ectodomains fused to the transmembrane and cytoplasmic domains of the NDV F and HN proteins, respectively, stimulate durable, protective anti-RSV neutralizing antibodies in mice. Furthermore, immunization of mice with a VLP containing a F/F chimera protein with modifications previously reported to stabilize the pre-fusion form of the RSV F protein resulted in significantly improved neutralizing antibody titers over VLPs containing the wild type F protein. The goal of this study was to determine if VLPs containing the pre-fusion form of the RSV F protein stimulated protective immune responses in cotton rats, a more RSV permissive animal model than mice. Read More

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November 2015

Murine immune responses to virus-like particle-associated pre- and postfusion forms of the respiratory syncytial virus F protein.

J Virol 2015 Jul 22;89(13):6835-47. Epub 2015 Apr 22.

Department of Microbiology and Physiological Systems, Program in Immunology and Microbiology, University of Massachusetts Medical School, Worcester, Massachusetts, USA

Unlabelled: Virus-like particles (VLPs) built on the Newcastle disease virus (NDV) core proteins, NP and M, and containing two chimeric proteins, F/F and H/G, composed of respiratory syncytial virus (RSV) fusion protein (F) and glycoprotein (G) ectodomains fused to the transmembrane and cytoplasmic domains of the NDV F and HN proteins, respectively, stimulate durable, protective RSV neutralizing antibodies in mice. Here, we report the properties of VLPs constructed to contain mutant RSV F protein ectodomains stabilized in prefusion (pre-F/F) or postfusion (post-F/F) configurations. The structures of the chimeric proteins assembled into VLPs were verified immunologically by their reactivities with a conformationally restricted anti-F protein monoclonal antibody. Read More

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