An enzyme-based immunodetection assay to quantify SARS-CoV-2 infection.

Area of Science:

• Virology
• Immunology
• Biotechnology

Background:

• The COVID-19 pandemic, caused by SARS-CoV-2, necessitates efficient diagnostic and research tools.
• Current methods like plaque assays and PCR for detecting SARS-CoV-2 are often slow, labor-intensive, and costly.
• There is a need for high-throughput, rapid, and cost-effective assays for SARS-CoV-2 research.

Purpose of the Study:

• To develop and validate a novel enzyme-based immunodetection assay for quantifying SARS-CoV-2 infection.
• To establish a rapid, quantitative, and cost-effective method for detecting de novo synthesized viral spike protein within infected cells.
• To provide an alternative assay for determining viral titers, drug efficacy, and serum neutralization.

Main Methods:

• Development of an enzyme-linked immunosorbent assay (ELISA) performed directly within fixed and permeabilized cells (in-cell ELISA).
• The assay directly quantifies the amount of newly synthesized viral spike protein.
• Standard ELISA protocols were adapted for cell-based detection without requiring specialized instrumentation.

Main Results:

• The in-cell ELISA provides rapid and quantitative detection of SARS-CoV-2 infection.
• The assay is versatile, working with different virus isolates and cell types.
• It enables accurate determination of TCID50, IC50 values for antiviral drugs, and serum neutralization activity.

Conclusions:

• The developed in-cell spike ELISA is a promising alternative to existing methods for studying SARS-CoV-2 infection.
• This assay facilitates high sample throughput and rapid diagnostics for COVID-19 research.
• The method offers a cost-effective and efficient approach for evaluating antiviral strategies and immune responses.