Neutralizing Antibody Assay Service
Overview
In the rapidly evolving landscape of therapeutic nucleic acid development, evaluating the efficacy of vaccine candidates is paramount. Central to this evaluation is the measurement of the humoral immune response, specifically the induction of neutralizing antibodies (NAbs). Unlike binding antibodies that simply attach to a pathogen, NAbs are functional proteins that block the entry of viruses into host cells, thereby preventing infection.
At CD BioGlyco, we offer the precision required to quantify protective immunity across preclinical phases. By integrating advanced virology techniques with high-throughput bioanalysis, we help researchers validate the immunogenicity of mRNA-lipid nanoparticle (mRNA-LNP) formulations and ensure that therapeutic candidates meet the stringent requirements.
Key Technologies
- Pseudovirus Neutralization Assay (pVNA)
We utilize non-replicating viral particles engineered to express the surface glycoproteins of the target pathogen, such as the SARS-CoV-2 spike protein. It allows for high-throughput screening in biosafety level 2 (BSL2) environments while maintaining high correlation with live virus assays. - Plaque Reduction Neutralization Test (PRNT)
PRNT measures the ability of a sample to reduce the formation of "plaques" or areas of cell death in a monolayer of susceptible cells. It provides an absolute quantification of viral neutralization. - Surrogate Virus Neutralization Test (sVNT)
This enzyme-linked immunosorbent assay (ELISA)-based competitive method mimics the virus-host interaction by measuring the inhibition of binding between the receptor-binding domain (RBD) and the host cell receptor (e.g., ACE2).
Empowering mRNA Vaccine Efficacy with Precision Neutralization Analytics
As part of our therapeutic nucleic acid development platform, CD BioGlyco offers an end-to-end suite of analysis services dedicated to the characterization of mRNA-elicited immune responses. Our service scope includes:
- Quantitative Titer Determination
Precise measurement of 50% neutralizing dose (ND50) or half-maximal inhibitory concentration (IC50) values in serum or plasma samples. - Cross-Variant Analysis
Evaluating the breadth of the immune response by testing NAb efficacy against multiple viral variants of concern (VOCs) is a critical step in modern mRNA vaccine design. - Isotype-Specific Neutralization
Assessing the contribution of different antibody classes (e.g., IgG, IgA) to the overall neutralizing activity.
Workflow
Project Consultation
We begin by discussing your specific mRNA candidate and target pathogen. Our experts define the most appropriate assay format (e.g., pVNA vs. PRNT) and select the relevant cell lines and viral strains to meet your research objectives.
Sample Quality Control
Samples (serum, plasma, or purified antibodies) are received and undergo strict quality control (QC) to ensure integrity. We verify sample stability and prepare standardized aliquots for analysis.
Preparation of Viral/Pseudoviral Stocks
We produce and titrate high-quality viral or pseudoviral stocks. For mRNA vaccine projects, we customize these stocks to express specific mutant glycoproteins relevant to your study.
Neutralization Reaction and Incubation
Serial dilutions of the test samples are co-incubated with a defined concentration of the virus. This step allows the neutralizing antibodies (NAbs) to bind to the viral surface and neutralize the infectious particles before they reach the target cells.
Cell Infection and Signal Detection
The virus-antibody mixture is added to target cell monolayers. After a specified incubation period, we measure the extent of infection using reporter systems (e.g., luciferase, GFP) or traditional staining methods.
Data Interpretation and Reporting
Sophisticated statistical models are used to calculate neutralizing titers. We provide a comprehensive report including raw data, neutralization curves, and comparative analysis against reference standards.
Publication Data
DoI: 10.1038/s41467-020-17892-0.
Journal: Nature Communications
IF: 15.7
Published: 2020
Results: This study develops a high-throughput fluorescence-based neutralization assay for SARS-CoV-2 using a reporter virus (mNG SARS-CoV-2) at ORF7. The assay quantifies neutralizing antibodies by measuring fluorescent cell reduction after serum-virus incubation, yielding NT50 values. Testing 60 COVID-19 patient sera and 60 pre-pandemic controls, it showed 100% specificity and high sensitivity, with patient NT50 ranging 35-5711. Results strongly correlate with the gold-standard PRNT (R2=0.85) and offer faster turnaround. The assay is specific, showing no cross-reactivity with sera from other infections or interfering substances. Suitable for 96-1536-well formats, it supports large-scale serodiagnosis, convalescent plasma screening, and vaccine evaluation, though it requires BSL-3 containment.
Fig.1 A high-throughput neutralizing antibody assay for COVID-19 diagnosis. (Muruato, et al., 2020)
Applications
mRNA Vaccine Immunogenicity Assessment
Critical for evaluating the protective potential of mRNA-based candidates. CD BioGlyco provides quantitative data on NAb induction, allowing researchers to optimize sequence design and LNP formulations for maximum protective efficacy.
Proclinical Monitoring
We support proclinical studies by providing longitudinal data on NAb persistence and decay. This is essential for determining dosing schedules and the potential requirement for booster doses.
Therapeutic Antibody Screening
Our platform facilitates the discovery and characterization of monoclonal antibodies (mAbs) intended for passive immunization. We help identify the most potent candidates by assessing their viral entry inhibition across diverse strains.
Epidemiological Surveillance
By analyzing NAb levels, we help track the evolution of "immune escape" variants, providing vital data for the development of next-generation multivalent mRNA vaccines.
Advantages
Versatile Assay Services
We offer a wide range of formats, including PRNT and pVNA. This flexibility ensures that we handle various viral targets and safety requirements, providing the most appropriate methodology for your specific project needs.
Unmatched Sensitivity and Specificity
Our optimized protocols and high-quality reagents minimize background noise and matrix interference. This results in highly sensitive assays capable of detecting low-titer NAb responses.
High-Throughput Capabilities
Leveraging automated liquid handling and advanced detection systems, CD BioGlyco processes thousands of samples simultaneously. This significantly reduces turnaround times.
Customized Viral Engineering
We specialize in the rapid generation of pseudoviruses carrying specific mutations. This enables our clients to stay ahead of viral evolution and test their mRNA vaccine candidates against emerging variants in real-time.
Frequently Asked Questions
Customer Review
The team at CD BioGlyco provided exceptional support for our mRNA vaccine candidate evaluation. Their pseudovirus neutralization assay was highly reproducible and gave us the critical data needed to select our lead LNP formulation.
— A.R., Senior Scientist
We were impressed by the rapid turnaround of the variant-specific NAb titers. CD BioGlyco engineers new spike proteins so quickly.
— R.S., Director of Immunology
The depth of the final report was outstanding. Having the validation data and statistical analysis saved us significant time and internal resources.
— A.R., Head of Regulatory Affairs
Associated Services
CD BioGlyco is committed to advancing the field of mRNA-based vaccine development by providing the most accurate and reliable neutralizing antibody assay service available. Our integration of advanced technology, high-throughput efficiency, and scientific expertise makes us the ideal partner for your bioanalysis needs. Please feel free to contact us to design a study that meets your specific requirements.
Reference
- Muruato, A.E.; et al. A high-throughput neutralizing antibody assay for COVID-19 diagnosis and vaccine evaluation. Nature Communications. 2020, 11: 4059. (Open Access)