A novel luciferase-based assay for quantifying coronavirus-induced syncytia

Area of Science:

• Virology
• Biochemistry
• Drug Discovery

Background:

• Coronaviruses induce cell-cell fusion, forming multinucleated syncytia via spike protein-receptor interactions.
• Quantifying syncytial formation is vital for antiviral drug screening.
• Existing methods for syncytia quantification are often low-throughput and labor-intensive.

Purpose of the Study:

• To develop a novel, high-throughput assay for quantifying coronavirus-induced syncytial formation.
• To enable efficient screening of antiviral compounds targeting feline coronavirus (FCoV) and SARS-CoV-2.

Main Methods:

• Development of a novel assay based on a split Gaussia luciferase (Gluc) system.
• Fusion of Gluc fragments to multimerizing Tau protein to reconstitute enzymatic activity upon cell fusion.
• Measurement of reconstituted luciferase activity in culture medium to quantify syncytial formation.

Main Results:

• The developed assay efficiently quantifies syncytial formation induced by FCoV and SARS-CoV-2.
• Demonstrated high-throughput capacity for syncytia quantification.
• Validated the assay's utility in measuring coronavirus-induced cell fusion.

Conclusions:

• The novel split luciferase assay provides an efficient and high-throughput method for quantifying coronavirus-induced syncytia.
• This assay can significantly accelerate the discovery and development of antiviral drugs targeting coronaviruses.