Dataset Information

Escape from neutralization by the respiratory syncytial virus-specific neutralizing monoclonal antibody palivizumab is driven by changes in on-rate of binding to the fusion protein.

ABSTRACT: The role of binding kinetics in determining neutralizing potency for antiviral antibodies is poorly understood. While it is believed that increased steady-state affinity correlates positively with increased virus-neutralizing activity, the relationship between association or dissociation rate and neutralization potency is unclear. We investigated the effect of naturally-occurring antibody resistance mutations in the RSV F protein on the kinetics of binding to palivizumab. Escape from palivizumab-mediated neutralization of RSV occurred with reduced association rate (Kon) for binding to RSV F protein, while alteration of dissociation rate (Koff) did not significantly affect neutralizing activity. Interestingly, linkage of reduced Kon with reduced potency mirrored the effect of increased Kon found in a high-affinity enhanced potency palivizumab variant (motavizumab). These data suggest that association rate is the dominant factor driving neutralization potency for antibodies to RSV F protein antigenic site A and determines the potency of antibody somatic variants or efficiency of escape of viral glycoprotein variants.

SUBMITTER: Bates JT

PROVIDER: S-EPMC4004766 | biostudies-literature | 2014 Apr

REPOSITORIES: biostudies-literature

ACCESS DATA

Publications

Escape from neutralization by the respiratory syncytial virus-specific neutralizing monoclonal antibody palivizumab is driven by changes in on-rate of binding to the fusion protein.

Bates John T JT Keefer Christopher J CJ Slaughter James C JC Kulp Daniel W DW Schief William R WR Crowe James E JE

Virology 20140303

The role of binding kinetics in determining neutralizing potency for antiviral antibodies is poorly understood. While it is believed that increased steady-state affinity correlates positively with increased virus-neutralizing activity, the relationship between association or dissociation rate and neutralization potency is unclear. We investigated the effect of naturally-occurring antibody resistance mutations in the RSV F protein on the kinetics of binding to palivizumab. Escape from palivizumab ...[more]

PMID: 24725940

Similar Datasets

Project description:Middle East respiratory syndrome coronavirus (MERS-CoV) causes a highly lethal pulmonary infection with ∼35% mortality. The potential for a future pandemic originating from animal reservoirs or health care-associated events is a major public health concern. There are no vaccines or therapeutic agents currently available for MERS-CoV. Using a probe-based single B cell cloning strategy, we have identified and characterized multiple neutralizing monoclonal antibodies (MAbs) specifically binding to the receptor-binding domain (RBD) or S1 (non-RBD) regions from a convalescent MERS-CoV-infected patient and from immunized rhesus macaques. RBD-specific MAbs tended to have greater neutralizing potency than non-RBD S1-specific MAbs. Six RBD-specific and five S1-specific MAbs could be sorted into four RBD and three non-RBD distinct binding patterns, based on competition assays, mapping neutralization escape variants, and structural analysis. We determined cocrystal structures for two MAbs targeting the RBD from different angles and show they can bind the RBD only in the "out" position. We then showed that selected RBD-specific, non-RBD S1-specific, and S2-specific MAbs given prophylactically prevented MERS-CoV replication in lungs and protected mice from lethal challenge. Importantly, combining RBD- and non-RBD MAbs delayed the emergence of escape mutations in a cell-based virus escape assay. These studies identify MAbs targeting different antigenic sites on S that will be useful for defining mechanisms of MERS-CoV neutralization and for developing more effective interventions to prevent or treat MERS-CoV infections.IMPORTANCE MERS-CoV causes a highly lethal respiratory infection for which no vaccines or antiviral therapeutic options are currently available. Based on continuing exposure from established reservoirs in dromedary camels and bats, transmission of MERS-CoV into humans and future outbreaks are expected. Using structurally defined probes for the MERS-CoV spike glycoprotein (S), the target for neutralizing antibodies, single B cells were sorted from a convalescent human and immunized nonhuman primates (NHPs). MAbs produced from paired immunoglobulin gene sequences were mapped to multiple epitopes within and outside the receptor-binding domain (RBD) and protected against lethal MERS infection in a murine model following passive immunization. Importantly, combining MAbs targeting distinct epitopes prevented viral neutralization escape from RBD-directed MAbs. These data suggest that antibody responses to multiple domains on CoV spike protein may improve immunity and will guide future vaccine and therapeutic development efforts.

Project description:Human astroviruses (HAstVs) cause severe diarrhea and represent an important health problem in children under two years of age. Despite their medical importance, the study of these pathogens has been neglected. To better understand the astrovirus antigenic structure and the basis of protective immunity, in this work we produced a panel of neutralizing monoclonal antibodies (Nt-MAbs) to HAstV serotypes 1, 2, and 8 and identified the mutations that allow the viruses to escape neutralization. We first tested the capacity of the recombinant HAstV capsid core and spike domains to elicit Nt-Abs. Hyperimmunization of animals with the two domains showed that although both induced a potent immune response, only the spike was able to elicit antibodies with neutralizing activity. Based on this finding, we used a mixture of the recombinant spike domains belonging to the three HAstV serotypes to immunize mice. Five Nt-MAbs were isolated and characterized; all of them were serotype specific, two were directed to HAstV-1, one was directed to HAstV-2, and two were directed to HAstV-8. These antibodies were used to select single and double neutralization escape variant viruses, and determination of the amino acid changes that allow the viruses to escape neutralization permitted us to define the existence of four potentially independent neutralization epitopes on the HAstV capsid. These studies provide the basis for development of subunit vaccines that induce neutralizing antibodies and tools to explore the possibility of developing a specific antibody therapy for astrovirus disease. Our results also establish a platform to advance our knowledge on HAstV cell binding and entry.IMPORTANCE Human astroviruses (HAstVs) are common etiological agents of acute gastroenteritis in children, the elderly, and immunocompromised patients; some virus strains have also been associated with neurological disease. Despite their medical importance, the study of these pathogens has advanced at a slow pace. In this work, we produced neutralizing antibodies to the virus and mapped the epitopes they recognize on the virus capsid. These studies provide the basis for development of subunit vaccines that induce neutralizing antibodies, as well as tools to explore the development of a specific antibody therapy for astrovirus disease. Our results also establish a platform to advance our knowledge on HAstV cell binding and entry.

Project description:Monoclonal antibodies are increasingly used for the prevention and/or treatment of viral infections. One caveat of their use is the ability of viruses to evolve resistance to antibody binding and neutralization. Computational strategies to identify viral mutations that may disrupt antibody binding would leverage the wealth of viral genomic sequence data to monitor for potential antibody-resistant mutations. The respiratory syncytial virus is an important pathogen for which monoclonal antibodies against the fusion (F) protein are used to prevent severe disease in high-risk infants. In this study, we used an approach that combines molecular dynamics simulations with FoldX to estimate changes in free energy in F protein folding and binding to the motavizumab antibody upon each possible amino acid change. We systematically selected 8 predicted escape mutations and tested them in an infectious clone. Consistent with our F protein stability predictions, replication-effective viruses were observed for each selected mutation. Six of the eight variants showed increased resistance to neutralization by motavizumab. Flow cytometry was used to validate the estimated (model-predicted) effects on antibody binding to F. Using surface plasmon resonance, we determined that changes in the on-rate of motavizumab binding were associated with the reduced affinity for two novel escape mutations. Our study empirically validated the accuracy of our molecular modeling approach and emphasized the role of biophysical protein modeling in predicting viral resistance to antibody-based therapeutics that can be used to monitor the emergence of resistant viruses and to design improved therapeutic antibodies. IMPORTANCE Respiratory syncytial virus (RSV) causes severe disease in young infants, particularly those with heart or lung diseases or born prematurely. Because no vaccine is currently available, monoclonal antibodies are used to prevent severe RSV disease in high-risk infants. While it is known that RSV evolves to avoid recognition by antibodies, screening tools that can predict which changes to the virus may lead to antibody resistance are greatly needed.

Dataset Information

Escape from neutralization by the respiratory syncytial virus-specific neutralizing monoclonal antibody palivizumab is driven by changes in on-rate of binding to the fusion protein.

Publications

Escape from neutralization by the respiratory syncytial virus-specific neutralizing monoclonal antibody palivizumab is driven by changes in on-rate of binding to the fusion protein.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets