A High-throughput Automated ELISA Assay for Detection of IgG Antibodies to the SARS-CoV-2 Spike Protein

Juliana Conkright-Fincham; Chieri Tomomori-Sato; Rich McGhee; Ella M Leslie; Carolyn J Beucher; Lauren E Weems; Shigeo Sato; William B Redwine; Kyle J Weaver; Brandon D Miller; Kym M Delventhal; John J Kary; Andrew B Koebbe; Alexander Dean; Jessica L Witt; Laura M Remy; Tari J Parmely; Chongbei Zhao; Yan Wang; Joan W Conaway; Jay R Unruh

doi:10.21769/BioProtoc.4301

A High-throughput Automated ELISA Assay for Detection of IgG Antibodies to the SARS-CoV-2 Spike Protein

Bio Protoc. 2022 Jan 20;12(2):e4301. doi: 10.21769/BioProtoc.4301.

Authors

Juliana Conkright-Fincham¹, Chieri Tomomori-Sato¹, Rich McGhee¹, Ella M Leslie¹, Carolyn J Beucher¹, Lauren E Weems¹, Shigeo Sato¹, William B Redwine¹, Kyle J Weaver¹, Brandon D Miller¹, Kym M Delventhal¹, John J Kary², Andrew B Koebbe³, Alexander Dean^{1

4}, Jessica L Witt¹, Laura M Remy¹, Tari J Parmely¹, Chongbei Zhao¹, Yan Wang¹, Joan W Conaway⁵, Jay R Unruh¹

Affiliations

¹ Stowers Institute for Medical Research, Kansas City, Missouri, USA.
² Kary Software LLC, Lawrence, Kansas, USA.
³ Checkout 51 Inc, Toronto, Ontario, Canada.
⁴ Zan Consulting LLC, Erie, Colorado, USA.
⁵ University of Texas, Southwestern, Dallas, Texas, USA.

Abstract

The SARS-CoV-2 pandemic and vaccination campaign has illustrated the need for high throughput serological assays to quantitatively measure antibody levels. Here, we present a protocol for a high-throughput colorimetric ELISA assay to detect IgG antibodies against the SARS-CoV-2 spike protein. The assay robustly distinguishes positive from negative samples, while controlling for potential non-specific binding from serum samples. To further eliminate background contributions, we demonstrate a computational pipeline for fitting ELISA titration curves, that produces an extremely sensitive antibody signal metric for quantitative comparisons across samples and time.

Keywords: COVID-19; ELISA; SARS-CoV-2; Serology; Spike protein.