Institute for Clinical Microbiology and Hygiene, University Hospital Regensburg, 93053 Regensburg, Germany
Matthias Vogel
Institute for Clinical Microbiology and Hygiene, University Hospital Regensburg, 93053 Regensburg, Germany
Annelie Plentz
Institute for Clinical Microbiology and Hygiene, University Hospital Regensburg, 93053 Regensburg, Germany
Josef Köstler
Institute for Clinical Microbiology and Hygiene, University Hospital Regensburg, 93053 Regensburg, Germany
Bernd Salzberger
Department for Infection Control and Infectious Diseases, University Hospital Regensburg, 93053 Regensburg, Germany
Jürgen J. Wenzel
Institute for Medical Microbiology and Hygiene, University of Regensburg, 93040 Regensburg, Germany
Hans Helmut Niller
Institute for Medical Microbiology and Hygiene, University of Regensburg, 93040 Regensburg, Germany
Jonathan Jantsch
Institute for Clinical Microbiology and Hygiene, University Hospital Regensburg, 93053 Regensburg, Germany
Ralf Wagner
Institute for Clinical Microbiology and Hygiene, University Hospital Regensburg, 93053 Regensburg, Germany; Institute for Medical Microbiology and Hygiene, University of Regensburg, 93040 Regensburg, Germany
Barbara Schmidt
Institute for Clinical Microbiology and Hygiene, University Hospital Regensburg, 93053 Regensburg, Germany
Institute for Clinical Microbiology and Hygiene, University Hospital Regensburg, 93053 Regensburg, Germany; Institute for Medical Microbiology and Hygiene, University of Regensburg, 93040 Regensburg, Germany
David Peterhoff
Institute for Clinical Microbiology and Hygiene, University Hospital Regensburg, 93053 Regensburg, Germany; Institute for Medical Microbiology and Hygiene, University of Regensburg, 93040 Regensburg, Germany; Corresponding author
Summary: SARS-CoV-2 Omicron is the first pandemic variant of concern exhibiting an abrupt accumulation of mutations particularly in the receptor-binding domain that is a critical target of vaccination induced and therapeutic antibodies. Omicron's mutations did only marginally affect the binding of ACE2, and the two antibodies Sotrovimab and CR3022 but strongly impaired the binding of Casirivimab and Imdevimab. Moreover, as compared with Wuhan, there is reduced serum reactivity and a pronounced loss of competitive surrogate virus neutralization (sVN) against Omicron in naïve vaccinees and in COVID-19 convalescents after infection and subsequent vaccination. Finally, although the booster vaccination response conferred higher titers and better sVN, the effect was nonetheless significantly lower compared with responses against Wuhan. Overall, our data suggest that the antigenicity of Omicrons receptor binding motive has largely changed but antibodies such as Sotrovimab targeting other conserved sites maintain binding and therefore hold potential in prophylaxis and treatment of Omicron-induced COVID-19.
