Antibody Screening Results for Anti-Nucleocapsid Antibodies Toward the Development of a Lateral Flow Assay to Detect SARS-CoV-2 Nucleocapsid Protein

Cate, David M.; Bishop, Joshua D.; Hsieh, Helen V.; Glukhova, Veronika A.; Alonzo, Luis F.; Hermansky, H. Gleda; Barrios-Lopez, Brianda; Grant, Benjamin D.; Anderson, Caitlin E.; Spencer, Ethan; Kuhn, Samantha; Gallagher, Ryan; Rivera, Rafael; Bennett, Crissa; Byrnes, Samantha A.; Connelly, John T.; Dewan, Puneet K.; Boyle, David S.; Weigl, Bernhard H.; Nichols, Kevin P.

[Image: see text] The global COVID-19 pandemic has created an urgent demand for large numbers of inexpensive, accurate, rapid, point-of-care diagnostic tests. Analyte-based assays are suitably rapid and inexpensive and can be rapidly mass-produced, but for sufficiently accurate performance, they require highly optimized antibodies and assay conditions. We used an automated liquid handling system, customized to handle arrays of lateral flow (immuno)assays (LFAs) in a high-throughput screen, to identify anti-nucleocapsid antibodies that will perform optimally in an LFA. We tested 1021 anti-nucleocapsid antibody pairs as LFA capture and detection reagents with the goal of highlighting pairs that have the greatest affinity for the nucleocapsid protein of SARS-CoV-2 within the LFA format. In contrast to traditional antibody screening methods (e.g., ELISA, bio-layer interferometry), the method described here integrates real-time reaction kinetics with transport in, and immobilization directly onto, nitrocellulose. We have identified several candidate antibody pairs that are suitable for further development of an LFA for SARS-CoV-2.