e-Article
Development and evaluation of low-volume tests to detect and characterize antibodies to SARS-CoV-2
Document Type
article
Author
Alice Halliday; Anna E. Long; Holly E. Baum; Amy C. Thomas; Kathryn L. Shelley; Elizabeth Oliver; Kapil Gupta; Ore Francis; Maia Kavanagh Williamson; Natalie Di Bartolo; Matthew J. Randell; Yassin Ben-Khoud; Ilana Kelland; Georgina Mortimer; Olivia Ball; Charlie Plumptre; Kyla Chandler; Ulrike Obst; Massimiliano Secchi; Lorenzo Piemonti; Vito Lampasona; Joyce Smith; Michaela Gregorova; Lea Knezevic; Jane Metz; Rachael Barr; Begonia Morales-Aza; Jennifer Oliver; Lucy Collingwood; Benjamin Hitchings; Susan Ring; Linda Wooldridge; Laura Rivino; Nicholas Timpson; Jorgen McKernon; Peter Muir; Fergus Hamilton; David Arnold; Derek N. Woolfson; Anu Goenka; Andrew D. Davidson; Ashley M. Toye; Imre Berger; Mick Bailey; Kathleen M. Gillespie; Alistair J. K. Williams; Adam Finn
Source
Frontiers in Immunology, Vol 13 (2022)
Subject
Language
English
ISSN
1664-3224
Abstract
Low-volume antibody assays can be used to track SARS-CoV-2 infection rates in settings where active testing for virus is limited and remote sampling is optimal. We developed 12 ELISAs detecting total or antibody isotypes to SARS-CoV-2 nucleocapsid, spike protein or its receptor binding domain (RBD), 3 anti-RBD isotype specific luciferase immunoprecipitation system (LIPS) assays and a novel Spike-RBD bridging LIPS total-antibody assay. We utilized pre-pandemic (n=984) and confirmed/suspected recent COVID-19 sera taken pre-vaccination rollout in 2020 (n=269). Assays measuring total antibody discriminated best between pre-pandemic and COVID-19 sera and were selected for diagnostic evaluation. In the blind evaluation, two of these assays (Spike Pan ELISA and Spike-RBD Bridging LIPS assay) demonstrated >97% specificity and >92% sensitivity for samples from COVID-19 patients taken >21 days post symptom onset or PCR test. These assays offered better sensitivity for the detection of COVID-19 cases than a commercial assay which requires 100-fold larger serum volumes. This study demonstrates that low-volume in-house antibody assays can provide good diagnostic performance, and highlights the importance of using well-characterized samples and controls for all stages of assay development and evaluation. These cost-effective assays may be particularly useful for seroprevalence studies in low and middle-income countries.