Determination of optimum levels of binding antibody units (BAU) of new quantitative chemiluminescent immuno-assay (CLIA) in COVID-19 vaccinated volunteer blood donors

Aseem Kumar Tiwari; Geet Aggarwal; Pratibha Kale; Neeti Yadav; Virendra Kumar; Gargi Singh; K Cheirmaraj; K Krishnan

doi:10.1016/j.transci.2024.103937

Determination of optimum levels of binding antibody units (BAU) of new quantitative chemiluminescent immuno-assay (CLIA) in COVID-19 vaccinated volunteer blood donors

Transfus Apher Sci. 2024 Apr 24;63(3):103937. doi: 10.1016/j.transci.2024.103937. Online ahead of print.

Authors

Aseem Kumar Tiwari¹, Geet Aggarwal², Pratibha Kale³, Neeti Yadav², Virendra Kumar⁴, Gargi Singh⁵, K Cheirmaraj⁶, K Krishnan⁷

Affiliations

¹ Department of Transfusion Medicine Medanta-The Medicity, Sector-38, Gurgaon, India. Electronic address: draseemtiwari@gmail.com.
² Department of Transfusion Medicine Medanta-The Medicity, Sector-38, Gurgaon, India.
³ Department of Clinical Microbiology Institute of Liver and Biliary Sciences, New Delhi, India.
⁴ Department of Microbiology College of Life Sciences, Jiwaji University Gwalior, India.
⁵ Medanta Institute of Education and Research Medanta-The Medicity, Sector-38, Gurgaon, India.
⁶ Independent Laboratory Consultant, Chennai, Tamil Nadu, India.
⁷ Laboratory Medicine, Thane West, Mumbai 400606, India.

PMID: 38678985
DOI: 10.1016/j.transci.2024.103937

Abstract

Background: For assessment of COVID-19 vaccine efficacy, neutralization activity of anti-SARS-CoV-2 antibody is measured. This study was undertaken to determine optimum levels of binding antibody units (BAU/ml) in new quantitative chemiluminescent assay (CLIA) that corresponded to neutralizing potential (30% inhibition) of sVNT assay.

Methods: Ninety-one blood samples were analyzed by CLIA and sVNT assays. Test samples (n = 75) were collected from blood donors post-2nd vaccination dose, while control samples (n = 16) were archived pre-COVID donor samples. Correlation between CLIA and sVNT was calculated and receiver operating characteristic (ROC) curve was drawn and analyzed.

Results: Results indicated excellent correlation between 57.5 BAU/ml on CLIA and 30%inhibition on sVNT assay. ROC curve analysis revealed that the area under the curve (AUC) was 0.971.

Discussion: The present study determined that 57.5 BAU/ml on CLIA corresponded to 30% inhibition on sVNT assay. Periodic quantitative analysis.

Keywords: IgG antibodies; Immunoassay; Neutralization; Quantitative CLIA; SVNT.