1. Titers of antibodies against ancestral SARS-CoV-2 correlate with levels of neutralizing antibodies to multiple variants.
- Author
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Tran, Trung The, Vaage, Eline Benno, Mehta, Adi, Chopra, Adity, Tietze, Lisa, Kolderup, Anette, Anthi, Aina, König, Marton, Nygaard, Gro, Lind, Andreas, Müller, Fredrik, Nissen-Meyer, Lise Sofie, Magnus, Per, Trogstad, Lill, Mjaaland, Siri, Søraas, Arne, Midtvedt, Karsten, Åsberg, Anders, Barratt-Due, Andreas, and Medhus, Asle W.
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ANTIBODY titer ,IMMUNOGLOBULINS ,SARS-CoV-2 Omicron variant ,SARS-CoV-2 ,PROTEIN domains ,COVID-19 vaccines - Abstract
Diagnostic assays currently used to monitor the efficacy of COVID-19 vaccines measure levels of antibodies to the receptor-binding domain of ancestral SARS-CoV-2 (RBDwt). However, the predictive value for protection against new variants of concern (VOCs) has not been firmly established. Here, we used bead-based arrays and flow cytometry to measure binding of antibodies to spike proteins and receptor-binding domains (RBDs) from VOCs in 12,000 serum samples. Effects of sera on RBD-ACE2 interactions were measured as a proxy for neutralizing antibodies. The samples were obtained from healthy individuals or patients on immunosuppressive therapy who had received two to four doses of COVID-19 vaccines and from COVID-19 convalescents. The results show that anti-RBDwt titers correlate with the levels of binding- and neutralizing antibodies against the Alpha, Beta, Gamma, Delta, Epsilon and Omicron variants. The benefit of multiplexed analysis lies in the ability to measure a wide range of anti-RBD titers using a single dilution of serum for each assay. The reactivity patterns also yield an internal reference for neutralizing activity and binding antibody units per milliliter (BAU/ml). Results obtained with sera from vaccinated healthy individuals and patients confirmed and extended results from previous studies on time-dependent waning of antibody levels and effects of immunosuppressive agents. We conclude that anti-RBDwt titers correlate with levels of neutralizing antibodies against VOCs and propose that our method may be implemented to enhance the precision and throughput of immunomonitoring. [ABSTRACT FROM AUTHOR]
- Published
- 2022
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