Multiplexed Serum Antibody Screening Platform Using Virus Extracts from Endemic Coronaviridae and SARS-CoV-2

Fink, Simon; Ruoff, Felix; Stahl, Aaron; Becker, Matthias; Kaiser, Philipp; Traenkle, Bjoern; Junker, Daniel; Weise, Frank; Ruetalo, Natalia; Hörber, Sebastian; Peter, Andreas; Nelde, Annika; Walz, Juliane; Krause, Gérard; Baillot, Armin; Schenke-Layland, Katja; Joos, Thomas O.; Rothbauer, Ulrich; Schneiderhan-Marra, Nicole; Schindler, Michael; Templin, Markus F.

[Image: see text] The presence of antibodies against endemic coronaviruses has been linked to disease severity after SARS-CoV-2 infection. Assays capable of concomitantly detecting antibodies against endemic coronaviridae such as OC43, 229E, NL63, and SARS-CoV-2 may help to elucidate this question. We developed a serum screening platform using a bead-based Western blot system called DigiWest, capable of running hundreds of assays using microgram amounts of protein prepared directly from different viruses. Characterization of the immunoassay for detection of SARS-CoV-2 specific antibodies revealed a sensitivity of 90.3% and a diagnostic specificity of 98.1%. Concordance analysis with the SARS-CoV-2 immunoassays available by Roche, Siemens, and Euroimmun indicates comparable assay performances (Cohen’s κ ranging from 0.8874 to 0.9508). Analogous assays for OC43, 229E, and NL63 were established and combined into one multiplex with the SARS-CoV-2 assay. Seroreactivity for different coronaviruses was detected with high incidence, and the multiplex assay was adapted for serum screening.