1. Efficacy of an unmodified bivalent mRNA vaccine against SARS-CoV-2 variants in female small animal models.
- Author
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Corleis, Björn, Hoffmann, Donata, Rauch, Susanne, Fricke, Charlie, Roth, Nicole, Gergen, Janina, Kovacikova, Kristina, Schlottau, Kore, Halwe, Nico Joel, Ulrich, Lorenz, Schön, Jacob, Wernike, Kerstin, Widera, Marek, Ciesek, Sandra, Mueller, Stefan O., Mettenleiter, Thomas C., Maione, Domenico, Petsch, Benjamin, Beer, Martin, and Dorhoi, Anca
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SARS-CoV-2 ,T cells ,COVID-19 vaccines ,IMMUNOGLOBULINS ,MESSENGER RNA ,ANIMAL models in research ,LABORATORY rats ,MONOCLONAL antibodies - Abstract
Combining optimized spike (S) protein-encoding mRNA vaccines to target multiple SARS-CoV-2 variants could improve control of the COVID-19 pandemic. We compare monovalent and bivalent mRNA vaccines encoding B.1.351 (Beta) and/or B.1.617.2 (Delta) SARS-CoV-2 S-protein in a transgenic mouse and a Wistar rat model. The blended low-dose bivalent mRNA vaccine contains half the mRNA of each respective monovalent vaccine, but induces comparable neutralizing antibody titres, enrichment of lung-resident memory CD8
+ T cells, antigen-specific CD4+ and CD8+ responses, and protects transgenic female mice from SARS-CoV-2 lethality. The bivalent mRNA vaccine significantly reduces viral replication in both Beta- and Delta-challenged mice. Sera from bivalent mRNA vaccine immunized female Wistar rats also contain neutralizing antibodies against the B.1.1.529 (Omicron BA.1 and BA.5) variants. These data suggest that low-dose and fit-for-purpose multivalent mRNA vaccines encoding distinct S-proteins are feasible approaches for extending the coverage of vaccines for emerging and co-circulating SARS-CoV-2 variants. Here the authors show efficacy of a low-dose, unmodified, bivalent mRNA vaccine against SARS-CoV-2 variants in two female rodent models and find that combination of mRNA encoding Beta and Delta Spike sequences induces broadly neutralizing antibodies and robust T-cell responses. [ABSTRACT FROM AUTHOR]- Published
- 2023
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