Rapid determination of SARS-CoV-2 antibody neutralization titer using Bio-Rad Bio-Plex correlates strongly with pseudovirus-determined neutralization titer

• Published in: Journal of virological methods Vol. 316; p. 114726
• Main Authors: Heaps, Amy L., Sobolewski, Michele D., Jacobs, Jana L., Gordon, Kelley C., Haidar, Ghady, Mellors, John W., Parikh, Urvi M.
• Format: Journal Article
• Language: English
• Published: Netherlands Elsevier B.V 01.06.2023; Published by Elsevier B.V
• Subjects: ACE2 competitive assay; Angiotensin-Converting Enzyme 2; Antibodies, Neutralizing; Antibodies, Viral; Bio-Plex; COVID-19 - diagnosis; Humans; Neutralizing antibody; Neutralizing titer (NT50); Pseudovirus assay; RNA Viruses; SARS-CoV-2; Bio-Plex; SARS-CoV-2; PSV; NT50; RBD; ACE2 competitive assay; Pseudovirus assay; BSL-3; Neutralizing titer (NT50); Neutralizing antibody; nAb
• ISSN: 0166-0934; 1879-0984
• DOI: 10.1016/j.jviromet.2023.114726

Accurate and rapid evaluation of SARS-CoV-2 half-maximal neutralizing antibody (nAb) titer (NT50) is an important research tool for measuring nAb responses after prophylaxis or therapeutics for COVID-19 prevention and management. Compared with ACE2-competitive enzyme immunoassays for nAb detection, pseudovirus assays remain low-throughput and labor intensive. A novel application of the Bio-Rad Bio-Plex Pro Human SARS-CoV-2 D614G S1 Variant nAb Assay was used to determine NT50 from COVID-19-vaccinated individuals and showed strong correlation to a laboratory-developed SARS-CoV-2 pseudovirus nAb assay. The Bio-Plex nAb assay could provide a rapid, high-throughput, culture-free method for NT50 determination in sera. •50 % neutralizing antibody titer (NT50) can be rapidly determined in an ACE2-competitive format.•NT50 determined using Bio-Plex or pseudovirus (PSV) are strongly correlated.•Bio-Plex is approximately 3-fold less sensitive than PSV for neutralizing antibody when concentrations are low.