Immunoassays for COVID-19 research and vaccine R&D
The emergence of the COVID-19 pandemic resulting from the spread of the SARS-CoV-2 virus has ignited intensive efforts to develop diagnostic tests to measure viral infections and antibody responses, together with vaccines and therapeutics.
As a result, the availability of serology assays that detect antibodies to SARS-CoV-2 in human serum is critical to understanding SARS-CoV-2 immune responses, measuring the impact of the virus on public health, and to supporting the development of effective vaccines and therapeutics.
Detection of SARS-CoV-2 antibodies in human serum
These time-critical efforts have put into focus the need for high-performance immunoassays to determine the levels of SARS-CoV-2 antibodies in human serum. To meet this need, a three-step bridging Gyrolab SARS-CoV-2 antibody immunoassay is now available. This assay has a broad dynamic range for qualitative detection of total antibodies generated against the receptor binding domain (RBD) of the spike (S) protein of SARS-CoV-2 in human serum samples.1
Cross-sectional model of coronavirus
The RBD of the S protein is directly involved in SARS-CoV binding to the human angiotensin-converting enzyme 2 (ACE2) receptor to enable viral entry into host cells and is a key target for vaccine and therapeutics development.
The three-step bridging Gyrolab SARS-CoV-2 antibody immunoassay utilizes a Gyrolab Bioaffy™ CD. The method encompasses a biotinylated SARS-CoV-2, Spike RBD-His recombinant protein as the capture molecule, and SARS‑CoV-2 Spike RBD-Fc recombinant protein labeled with Alexa Fluor® 647 as the detection molecule. The assay detects IgG, IgA and IgM antibody subtypes in human serum.
Dynamic range of Gyrolab SARS-CoV-2 antibody immunoassay
A series of standard samples was prepared to determine the immunoassay dynamic range. The assay dynamic range is 40 ng/mL to 200 µg/mL.
Average responses obtained for a negative control (NC) and positive controls ranging from 40 ng/mL to 200 µg/mL (in neat serum) in Rexxip H containing 25% human serum. Rabbit polyclonal anti-SARS-CoV-2 Spike RBD antibody was used as positive control.
Gyrolab immunoassays for vaccine development
Bioanalysis during vaccine development presents many challenges, including diversity of assay complexity, sample matrices, analyte types, and demands on workflow efficiency. There is an additional demand for rapid data generation as project timelines for COVID-19 vaccine development are compressed to shorten development time with the goal to combat the pandemic.
Immunoassay speed is maximized with Gyrolab platform, since the long incubation times for manual ELISAs are eliminated.
Customer example of improvements in analysis time, dynamic range, sample savings, and assay development time when transitioning from ELISA to Gyrolab immunoassay.
Immunoassays are used in vaccine development to characterize vaccine titer, purity, affinity, and potency, as well as their immunogenic response in both animals and humans. Gyrolab assay flexibility enables multiple assays to be run on a single Gyrolab Bioaffy CD as in the example below.
Immunogenicity responses in a preclinical mouse study detecting IgG antibody subtypes simultaneously in a single run were analyzed with Gyrolab immunoassays to screen responses from different formulations.
Read the Spin Blog posts to learn about better tools for vaccine bioanalysis:
Gyrolab PK immunoassays for COVID-19 antibody therapeutics
The repurposing of currently approved antibody therapeutics for COVID-19 is an intense area of interest, since approved drugs have already been shown to be safe in humans and clinical trial timelines are dramatically shortened to reach patients. One target for treatment is the prevention of cytokine storms that can lead to acute respiratory distress syndrome (ARDS) in COVID-19 patients.
Cytokine storms, or high-level immune responses with the rapid release of inflammatory cytokines, is a possible mechanism for development of critical respiratory distress syndrome causing serious illness. Since IL-6 is one of the pro-inflammatory cytokines released, Actembra® (tocilizumab), an FDA-approved IL-6 inhibitor, is currently being evaluated in a Phase III clinical trial as a potential therapeutic intervention in hospitalized adult patients with severe COVID-19 pneumonia.
To accelerate immunoassay bioanalysis for IL-6 inhibitor development, a Gyrolab tocilizumab PK assay protocol is now available.
For more information, Contact Us and one of our scientists would be glad to help you.
Learn more about Gyrolab immunoassays technology
Centrifugal force and a flow-through affinity microcolumn format eliminates lengthy incubations and minimizes matrix interference in Gyrolab immunoassays. The nanoliter-scale format saves reagents and samples, resulting in a cost effective and highly reproducible immunoassay that produces quality data over broad dynamic ranges. Gyrolab Bioaffy™ CDs combined with Gyrolab automated systems dramatically reduce hands-on time and shorten processing times, leading to considerable gains in productivity.