Protein-based RBD-C-tag COVID-19 Vaccination Candidate Elicits Protection Activity against SARS-COV-2 Variant Infection

Herrmann, A.; Subramani, J.; Shaabani, N.; Shetty, D.; Wu, H.; Kwon, S.; Li, W.; Yue, C.; Lahtz, C.; Ramirez-Torres, A.; Zhou, H.; Zhang, Y.; Allen, R. D.; Farley, B.; Emalfarb, M.; Tchelet, R.; Markku, S.; Marika, V.; Wiebe, M.; Huuskonen, A.; Ben-artzi, H.; Avigdor, A.; Ji, H.

doi:10.1101/2021.08.17.456704

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bioRxiv · 10.1101/2021.08.17.456704

Protein-based RBD-C-tag COVID-19 Vaccination Candidate Elicits Protection Activity against SARS-COV-2 Variant Infection

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Abstract

The identification of a vaccination candidate against COVID-19 providing protecting activity against emerging SARS-COV-2 variants remains challenging. Here, we report protection activity against a spectrum of SARS-COV-2 and variants by immunization with protein-based recombinant RBD-C-tag administered with aluminum-phosphate adjuvant intramuscularly. Immunization of C57BL/6 mice with RBD-C-tag resulted in the in vivo production of IgG antibodies recognizing the immune-critical spike protein of the SARS-COV-2 virus as well as the SARS-COV-2 variants alpha ("United Kingdom"), beta ("South Africa"), gamma ("Brazil/Japan"), and delta ("India") as well as wt-spike protein. RBD-C-tag immunization led to a desired Th1 polarization of CD4 T cells producing IFN{gamma}. Importantly, RBD-C-tag immunization educated IgG production delivers antibodies that exert neutralizing activity against the highly transmissible SARS-COV-2 virus strains "Washington", "South Africa" (beta), and "India" (delta) as determined by conservative infection protection experiments in vitro. Hence, the protein-based recombinant RBD-C-tag is considered a promising vaccination candidate against COVID-19 and a broad range of emerging SARS-COV-2 virus variants.

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Herrmann, A., Subramani, J., Shaabani, N., Shetty, D., Wu, H., Kwon, S., Li, W., Yue, C., Lahtz, C., Ramirez-Torres, A., Zhou, H., Zhang, Y., Allen, R. D., Farley, B., Emalfarb, M., Tchelet, R., Markku, S., Marika, V., Wiebe, M., Huuskonen, A., Ben-artzi, H., Avigdor, A., Ji, H.. 2021-08-18. Protein-based RBD-C-tag COVID-19 Vaccination Candidate Elicits Protection Activity against SARS-COV-2 Variant Infection. https://doi.org/10.1101/2021.08.17.456704

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