LIPS Method for the Detection of SARS-CoV-2 Antibodies to Spike and Nucleocapsid Proteins

Eur J Immunol. 2020 Jun 25. doi: 10.1002/eji.202048715. Online ahead of print.

Abstract

Profiling antibodies to SARS-CoV-2 can help to assess potential immune response after COVID-19 disease. Luciferase IP system (LIPS) assay is a sensitive method for quantitative detection of antibodies to antigens in their native conformation. We here describe LIPS to detect antibody responses to SARS-CoV-2 spike (S) and nucleocapsid (N) proteins in COVID-19 patients. The antibodies targeted both S and N fragments and gave a high assay sensitivity by identifying 26 out of 26 COVID-19 patients with N antigen or with three protein fragments when combined into a single reaction. The assay correlated well with ELISA method and was specific to COVID-19 as we saw no reactivity among uninfected healthy controls. Our results show that LIPS is a rapid and measurable method to screen antibody responses against SARS-CoV-2 antigens.

Keywords: COVID-19; LIPS; SARS-CoV-2; antibodies; luciferase immunoprecipitation.