A homogeneous split-luciferase assay for rapid and sensitive detection of anti-SARS CoV-2 antibodies

Better diagnostic tools are needed to combat the ongoing COVID-19 pandemic. Here, to meet this urgent demand, we report a homogeneous immunoassay to detect IgG antibodies against SARS-CoV-2. This serological assay, called SATiN, is based on a tri-part Nanoluciferase (tNLuc) approach, in which the spike protein of SARS-CoV-2 and protein G, fused respectively to two different tNLuc tags, are used as antibody probes. Target engagement of the probes allows reconstitution of a functional luciferase in the presence of the third tNLuc component. The assay is performed directly in the liquid phase of patient sera and enables rapid, quantitative and low-cost detection. We show that SATiN has a similar sensitivity to ELISA, and its readouts are consistent with various neutralizing antibody assays. This proof-of-principle study suggests potential applications in diagnostics, as well as disease and vaccination management. Serological tests are important diagnostic and disease surveillance tools for addressing the COVID-19 pandemic. Here, the authors present a tri-part Nanoluciferase based assay to detect antibodies against SARS-CoV-2.

Automated summary

A tri-part Nanoluciferase-based assay named SATiN is developed for detecting antibodies against SARS-CoV-2, showing similar sensitivity to ELISA and consistent results with various neutralizing antibody assays. This assay, performed directly in patient sera, offers rapid, quantitative, and cost-effective detection, suggesting potential applications in diagnostics and disease management.