Publications by authors named "Whitener B"

The COVID-19 pandemic underscored the promise of monoclonal antibody-based prophylactic and therapeutic drugs and revealed how quickly viral escape can curtail effective options. When the SARS-CoV-2 Omicron variant emerged in 2021, many antibody drug products lost potency, including Evusheld and its constituent, cilgavimab. Cilgavimab, like its progenitor COV2-2130, is a class 3 antibody that is compatible with other antibodies in combination and is challenging to replace with existing approaches.

View Article and Find Full Text PDF

Most neutralizing anti-SARS-CoV-2 monoclonal antibodies (mAbs) target the receptor binding domain (RBD) of the spike (S) protein. Here, we characterize a panel of mAbs targeting the N-terminal domain (NTD) or other non-RBD epitopes of S. A subset of NTD mAbs inhibits SARS-CoV-2 entry at a post-attachment step and avidly binds the surface of infected cells.

View Article and Find Full Text PDF

MXRA8 is a receptor for chikungunya (CHIKV) and other arthritogenic alphaviruses with mammalian hosts. However, mammalian MXRA8 does not bind to alphaviruses that infect humans and have avian reservoirs. Here, we show that avian, but not mammalian, MXRA8 can act as a receptor for Sindbis, western equine encephalitis (WEEV), and related alphaviruses with avian reservoirs.

View Article and Find Full Text PDF
Article Synopsis
  • The study explores new mRNA vaccine strategies to enhance effectiveness against COVID-19, focusing on specific protein domains of the virus instead of the full-length spike protein.
  • The candidate vaccine mRNA-1283, combining the N-terminal domain and receptor binding domain, shows better antigen expression, stronger antibody responses, and improved stability compared to existing vaccines.
  • In animal tests, mRNA-1283 elicits equal or greater immune protection against various COVID-19 variants, supporting its advancement to clinical trials for further evaluation.
View Article and Find Full Text PDF

Currently circulating SARS-CoV-2 variants have acquired convergent mutations at hot spots in the receptor-binding domain (RBD) of the spike protein. The effects of these mutations on viral infection and transmission and the efficacy of vaccines and therapies remains poorly understood. Here we demonstrate that recently emerged BQ.

View Article and Find Full Text PDF
Article Synopsis
  • * Vaccine-induced antibodies interact with Fc gamma receptors (FcγRs) and have been linked to better clinical outcomes, although a direct cause-and-effect relationship hasn't been confirmed.
  • * Research using mouse models shows that effective immune response against SARS-CoV-2 variants, including Omicron, relies on FcγR engagement and the presence of alveolar macrophages for proper antibody-mediated protection.
View Article and Find Full Text PDF

Currently circulating SARS-CoV-2 variants acquired convergent mutations at receptor-binding domain (RBD) hot spots. Their impact on viral infection, transmission, and efficacy of vaccines and therapeutics remains poorly understood. Here, we demonstrate that recently emerged BQ.

View Article and Find Full Text PDF

Cleavage of the flavivirus premembrane (prM) structural protein during maturation can be inefficient. The contribution of partially mature flavivirus virions that retain uncleaved prM to pathogenesis during primary infection is unknown. To investigate this question, we characterized the functional properties of newly-generated dengue virus (DENV) prM-reactive monoclonal antibodies (mAbs) in vitro and using a mouse model of DENV disease.

View Article and Find Full Text PDF
Article Synopsis
  • - Emerging SARS-CoV-2 variants show antigenic changes in the spike protein that make them less susceptible to antibodies from vaccines like mRNA-1273 and BNT162b2, but these vaccines still protect against severe illness and death.
  • - The study investigates the role of Fc gamma receptors (FcγRs) in mediating antibody protection against infection, finding that vaccine-induced antibodies need Fc effector functions for effective neutralization of new variants.
  • - Research on mice reveals that without specific FcγRs and alveolar macrophages, the protective effects of the mRNA-1273 vaccine against variants like Omicron BA.5 are significantly reduced, highlighting the importance of these immune components in vaccine efficacy.
View Article and Find Full Text PDF

The COVID-19 pandemic underscored the promise of monoclonal antibody-based prophylactic and therapeutic drugs, but also revealed how quickly viral escape can curtail effective options. With the emergence of the SARS-CoV-2 Omicron variant in late 2021, many clinically used antibody drug products lost potency, including Evusheld and its constituent, cilgavimab. Cilgavimab, like its progenitor COV2-2130, is a class 3 antibody that is compatible with other antibodies in combination and is challenging to replace with existing approaches.

View Article and Find Full Text PDF
Article Synopsis
  • * Researchers tested two new bivalent vaccines (mRNA-1273.214 and mRNA-1273.222) in mice and found they produced stronger antibody responses against Omicron variants compared to the original vaccine.
  • * Administering these bivalent vaccines as boosters significantly improved immune protection and reduced lung infection severity in mice, highlighting their potential effectiveness against circulating strains.
View Article and Find Full Text PDF
Article Synopsis
  • The emergence of SARS-CoV-2 variants in the Omicron lineage has led to reduced vaccine effectiveness and ongoing virus transmission due to the spike protein's ability to evade antibodies.
  • Researchers evaluated two bivalent vaccines that include mRNAs for spike proteins from both the original virus and recent variants (BA.1 or BA.4/5) and found they produced stronger immune responses in mice compared to existing monovalent vaccines.
  • When used as a booster after initial vaccination, these bivalent vaccines not only generated a more robust antibody response but also provided greater protection against BA.5 infections and reduced inflammation in the lungs.
View Article and Find Full Text PDF
Article Synopsis
  • Researchers developed a new mRNA vaccine, mRNA-1283, targeting specific spike protein domains of the virus responsible for COVID-19.
  • This vaccine demonstrated enhanced antigen expression, antibody responses, and stability when stored in refrigerated conditions compared to the existing mRNA-1273 vaccine.
  • In preclinical tests, mRNA-1283 provided similar or better immune protection against various COVID-19 variants in mice, indicating its potential for human clinical trials.
View Article and Find Full Text PDF

Omicron variant strains encode large numbers of changes in the spike protein compared to historical SARS-CoV-2 isolates. Although in vitro studies have suggested that several monoclonal antibody therapies lose neutralizing activity against Omicron variants, the effects in vivo remain largely unknown. Here, we report on the protective efficacy against three SARS-CoV-2 Omicron lineage strains (BA.

View Article and Find Full Text PDF

Background: Since the emergence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in 2019, viral variants with greater transmissibility or immune-evasion properties have arisen, which could jeopardize recently deployed vaccine- and antibody-based countermeasures.

Methods: Here, we evaluated in mice and hamsters the efficacy of a pre-clinical version of the Moderna mRNA vaccine (mRNA-1273) and the Johnson & Johnson recombinant adenoviral-vectored vaccine (Ad26.COV2.

View Article and Find Full Text PDF
Article Synopsis
  • The emergence of new SARS-CoV-2 variants threatens the effectiveness of immunity from previous infections or vaccinations.
  • To tackle this issue, the NIH launched the SARS-CoV-2 Assessment of Viral Evolution (SAVE) program for real-time assessment of variant risks that might impact transmission and vaccine efficacy.
  • The program focuses on gathering and analyzing data on emerging variants and their effects on immunity, using animal models, while also addressing future challenges in monitoring rapidly evolving viruses.
View Article and Find Full Text PDF
Article Synopsis
  • The Omicron variant B.1.1.529 has raised concerns about its ability to evade vaccine protection and therapeutic antibodies.
  • Research using mice and hamsters revealed that B.1.1.529 caused less severe respiratory infections compared to previous SARS-CoV-2 variants, even though it binds strongly to mouse ACE2.
  • The findings indicate a milder disease response in rodents infected with B.1.1.529, which aligns with some early clinical observations in humans.
View Article and Find Full Text PDF

Despite the development and deployment of antibody and vaccine countermeasures, rapidly-spreading SARS-CoV-2 variants with mutations at key antigenic sites in the spike protein jeopardize their efficacy. The recent emergence of B.1.

View Article and Find Full Text PDF

Although mRNA vaccines encoding the spike protein of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) prevent COVID-19, the emergence of new viral variants jeopardizes their efficacy. Here, we assessed the immunogenicity and protective activity of historical (mRNA-1273, designed for Wuhan-1 spike protein) or modified (mRNA-1273.351, designed for B.

View Article and Find Full Text PDF

With the emergence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variants with increased transmissibility and potential resistance, antibodies and vaccines with broadly inhibitory activity are needed. Here, we developed a panel of neutralizing anti-SARS-CoV-2 monoclonal antibodies (mAbs) that bound the receptor binding domain of the spike protein at distinct epitopes and blocked virus attachment to its host receptor, human angiotensin converting enzyme-2 (hACE2). Although several potently neutralizing mAbs protected K18-hACE2 transgenic mice against infection caused by ancestral SARS-CoV-2 strains, others induced escape variants in vivo or lost neutralizing activity against emerging strains.

View Article and Find Full Text PDF

Although mRNA vaccines prevent COVID-19, variants jeopardize their efficacy as immunity wanes. Here, we assessed the immunogenicity and protective activity of historical (mRNA-1273, designed for Wuhan-1 spike) or modified (mRNA-1273.351, designed for B.

View Article and Find Full Text PDF

With the emergence of SARS-CoV-2 variants with increased transmissibility and potential resistance, antibodies and vaccines with broadly inhibitory activity are needed. Here we developed a panel of neutralizing anti-SARS-CoV-2 mAbs that bind the receptor binding domain of the spike protein at distinct epitopes and block virus attachment to cells and its receptor, human angiotensin converting enzyme-2 (hACE2). While several potently neutralizing mAbs protected K18-hACE2 transgenic mice against infection caused by historical SARS-CoV-2 strains, others induced escape variants in vivo and lost activity against emerging strains.

View Article and Find Full Text PDF

Although the fields of public health and health services research have much in common, public health practitioners--in their daily encounters with practical, frontline challenges--may not be aware of the quantity and the quality of information generated by health services research that is directly related to public health activities. We describe a number of health services research resources that public health practitioners may find useful, including an overview of these resources and several in-depth examples.

View Article and Find Full Text PDF