Correlation between SARS-COV-2 antibody screening by immunoassay and neutralizing antibody testing

Author(s):Show less -

Mendrone-Junior, Alfredo ^{[1, 2]} ; Dinardo, Carla Luana ^{[1, 3]} ; Ferreira, Suzete Cleuza ^[1] ; Nishya, Anna ^[1] ; Salles, Nanci Alves ^[1] ; de Almeida Neto, Cesar ^[1] ; Hamasaki, Debora Toshei ^[1] ; Facincani, Tila ^[1] ; de Oliveira Alves, Lucas Bassolli ^[4] ; Machado, Rafael Rahal Guaragna ^[5] ; Araujo, Danielle Bastos ^[5] ; Durigon, Edison Luiz ^{[5, 6]} ; Rocha, Vanderson ^{[1, 2, 4]} ; Sabino, Ester Cerdeira ^[3]

Affiliation

^[1] Undacao Pro Sangue Hemoctr Sao Paulo, Sao Paulo - Brazil

^[2] Univ Sao Paulo, Med Sch, Lab Med Invest Pathogenesis & Directed Therapy On, HCFMUSP, Sao Paulo - Brazil

^[3] FMUSP, Inst Med Trop, Sao Paulo - Brazil

^[4] Serv Hematol Hemoterapia & Terapia Celular HCFMUS, Sao Paulo - Brazil

^[5] Univ Sao Paulo, Inst Ciencias Biomed, Dept Microbiol, Sao Paulo - Brazil

^[6] Sci Platform Pasteur USP, Sao Paulo - Brazil

• Document type: Journal article
• Source: Transfusion; v. 61, n. 4, p. 1181-1190, APR 2021.
• Web of Science Citations: 8

Abstract

Background The efficacy of convalescent plasma (CP), an alternative for the treatment of COVID-19, depends on high titers of neutralizing antibodies (nAbs), but assays for quantifying nAbs are not widely available. Our goal was to develop a strategy to predict high titers of nAbs based on the results of anti-SARS-CoV-2 immunoassays and the clinical characteristics of CP donors. Study Design and Methods A total of 214 CP donors were enrolled and tested for the presence of anti-SARS-CoV-2 antibodies (IgG) using two commercial immunoassays: EUROIMMUN (ELISA) and Abbott (Chemiluminescence). Quantification of nAbs was performed using the Cytopathic Effect-based Virus Neutralization test. Three criteria for identifying donors with nAbs >= 1:160 were tested: - C1: Curve ROC; - C2: Conditional decision tree considering only the IA results and - C3: Conditional decision tree including both the IA results and the clinical variables. Results The performance of the immunoassays was similar referring to both S/CO and predictive value for identifying nAbs titers >= 1:160. Regarding the studied criteria for identifying CP donors with high nAbs titers: (a) C1 showed 76.1% accuracy if S/CO = 4.65, (b) C2 presented 76.1% accuracy if S/CO >= 4.57 and (c) C3 had 71.6% accuracy if S/CO was >= 4.57 or if S/CO was between 2.68-4.57 and the last COVID-19-related symptoms were recent (within 19 days). Conclusion SARS-CoV-2 IgG immunoassays (S/CO) can be used to predict high anti-SARS-CoV-2 nAbs titers. This study has proposed different criteria for identifying donors with >= 1:160 nAbs titers, all with high efficacy. (AU)

• FAPESP's process: 16/20045-7 - Antigen discovery and development of serological diagnostic methods and vaccine approaches against the Zika Virus (ZIKV)
• Grantee: Luis Carlos de Souza Ferreira
• Support Opportunities: Research Projects - Thematic Grants
• FAPESP's process: 20/06409-1 - Evaluation of humoral immune response and inflammatory response in patients with confirmed diagnosis of COVID-19 at Hospital Sírio Libanês and correlation with disease severity
• Grantee: Edison Luiz Durigon
• Support Opportunities: Regular Research Grants
• FAPESP's process: 17/24769-2 - Zika virus in postpartum women and newborns: seroepidemiology and molecular characterization
• Grantee: Rafael Rahal Guaragna Machado
• Support Opportunities: Scholarships in Brazil - Doctorate (Direct)