Single-Dilution COVID-19 Antibody Test with Qualitative and Quantitative Readouts

Area of Science:

• Immunology
• Virology
• Public Health

Background:

• The COVID-19 pandemic necessitates robust serological testing for surveillance and immune response assessment.
• Serology tests detect past SARS-CoV-2 exposure, complementing molecular tests for active infections, crucial for asymptomatic cases.
• Existing serological methods may have limitations in scalability or reagent availability.

Purpose of the Study:

• To develop and validate a sensitive and specific laboratory-developed antibody test for SARS-CoV-2 exposure.
• To enable quantification of IgG titers against the SARS-CoV-2 spike glycoprotein from a single sample measurement.
• To provide a cost-effective and adaptable serology assay for clinical deployment and public health surveillance.

Main Methods:

• Development of an enzyme-linked immunosorbent assay (ELISA) using research-grade reagents.
• Qualitative and quantitative detection of IgG and IgA antibodies against the SARS-CoV-2 spike glycoprotein.
• Validation of test sensitivity, specificity, and ability to estimate IgG titers from single measurements.

Main Results:

• The developed ELISA demonstrates high sensitivity and specificity in detecting SARS-CoV-2 exposure.
• The assay accurately estimates viral spike-specific IgG titers from a single sample measurement.
• The test is adaptable and cost-effective, suitable for high-throughput clinical environments.

Conclusions:

• The described ELISA is a valuable tool for serological surveillance of COVID-19.
• The test provides a simple, scalable method to measure individual immune responses to SARS-CoV-2 infection or vaccination.
• This accurate and cost-effective assay is well-suited for clinical deployment in the ongoing pandemic.