
Asia Pacific Academy of Science Pte. Ltd. (APACSCI) specializes in international journal publishing. APACSCI adopts the open access publishing model and provides an important communication bridge for academic groups whose interest fields include engineering, technology, medicine, computer, mathematics, agriculture and forestry, and environment.

Sensitivity of serology assay in Covid-19 diagnosis: does the antigen matter?
Vol 35, Issue 3, 2021
Abstract
Since the spreading of Sar-CoV-2 in March 2020, many serologic tests have been developed to identify antibody responses. Indeed, different commercial kits are directed against different antigens and could utilise different methods thereby triggering confusion and criticism. Here, we compared two Food and Drug Administration (FDA)-approved automatized assays that detect IgG responses against spike or nucleocapsid protein of Sars-Cov-2 virus in 127 subjects among healthcare workers of IRCCS Policlinico San Donato (MI), Italy. We observed different kinetics of IgG responses, demonstrating the importance of timing of sampling to correctly interpret the results both for infection diagnosis and for epidemiologic studies. We observed that Anti-N response starts earlier than Anti-S1/S2 response but also decreases earlier, affecting the sensitivity of the tests at different time points. Combining two different assays, designed against different antigens, could reduce false negative results. Finally, we observed a patient who produced anti-nucleocapsid IgG, but not anti-spike IgG. In conclusion, we investigated antibody responses in Covid-19 disease, aiming to direct clinicians and laboratory scientists to correctly interpret serologic results by always paying attention to clinical history correlation, timing of sampling, methods and antigens used, to avoid false negative results and obtain relevant epidemiologic data.
Keywords
References
Supporting Agencies
Copyright (c) 2021 C Sitzia, L Pistelli, R Cardani, LV Renna, M Ranucci, M Carrara, S Borlini, P Clerici, B Rampoldi, M Cornetta, M Corsi-Romanelli
This site is licensed under a Creative Commons Attribution 4.0 International License (CC BY 4.0).

Medical Genetics, University of Torino Medical School, Italy

Department of Biomedical, Surgical and Dental Sciences, University of Milan, Italy