Abstract
The accurate measurement of serological response to SARS-CoV-2 vaccination is needed to correlate responses with effective protective immunity. The World Health Organization (WHO) has created an international standard to allow harmonization of immune response assessment to an arbitrary unit across different commercial assays; however, the accuracy of reporting of SARS-CoV-2 spike antibody titers in international standard units (BAU or IU/mL) from commercial assays is not well studied. Here, we report the performance comparison of four quantitative commercial assays testing for SARS-CoV-2 spike immunoglobins using the WHO’s international standard. Sera, EDTA-plasma and heparinized plasma collected from individuals who are vaccine naïve or received BNT162b2 (Pfizer/BioNTech), mRNA-1273 (Moderna) or ChAdOx1-S (Oxford-AstraZeneca) were tested using Abbott Architect AdviseDx SARS-CoV-2 IgG II, DiaSorin LIAISON SARS-CoV-2 TrimericS IgG, Roche Elecsys Anti-SARS-CoV-2 S and GenScript cPass SARS-CoV-2 surrogate virus neutralization assays. The sensitivities ranged from 90% to 100%, and specificities from 88% to 100%. These four assays had excellent agreement (0.79-0.93) and correlation (0.87-0.97); however, Passing-Bablok regression analysis indicated that data generated by these assays were not comparable. Our data suggests that natural SARS-CoV-2 infection elicited a greater antibody response compared to vaccines, evident by a significantly higher neutralizing antibody titer in unvaccinated individuals who seroconverted.
Keywords: Antibodies; COVID-19; Immunoglobulin; Quantitative serological assays; SARS-CoV-2; WHO international standard.
【저자키워드】 COVID-19, antibodies, SARS-CoV-2, Immunoglobulin, WHO international standard., Quantitative serological assays, 【초록키워드】 IgG, Vaccine, immune response, Vaccines, mRNA-1273, SARS-COV-2 infection, Antibody Response, BNT162b2, sensitivity, specificity, Accuracy, protective immunity, BAU, response, International, Antibody titer, plasma, WHO, correlation, Roche, serological, Quantitative, SARS-CoV-2 IgG, SARS-CoV-2 vaccination, Moderna, Neutralizing antibody titer, SARS-CoV-2 spike, serological response, ChAdOx1-S, Pfizer/BioNTech, Oxford-AstraZeneca, LIAISON, Abbott, World Health Organization, regression analysis, individual, DiaSorin, naïve, Architect, virus neutralization assays, Genscript, effective, greater, tested, collected, indicated, seroconverted, significantly higher, comparable, the WHO, elicited, ranged, Elecsy, 【제목키워드】 antibody, Quantitative, SARS-CoV-2 spike, Standard, World Health Organization, unit,