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bioRxiv · 10.1101/2021.08.13.456164

Comparison of Wild Type DNA Sequence of Spike Protein from SARS-CoV-2 with Optimized Sequence on The Induction of Protective Responses Against SARS-Cov-2 Challenge in Mouse Model

Abstract

COVID-19 caused by SARS-CoV-2 has been spreading worldwide. To date, several vaccine candidates moved into EUA or CA applications. Although DNA vaccine is on phase III clinical trial, it is a promised technology platform with many advantages. Here, we showed that the pGX9501 DNA vaccine encoded the spike full-length protein-induced strong humoral and cellular immune responses in mice with higher neutralizing antibodies, blocking the hACE2-RBD binding against live virus infection in vitro. Importantly, higher levels of IFN-{gamma} expression in CD8+ and CD4+ T cell and specific cytotoxic lymphocyte (CTL) killings effect were also observed in the pGX9501-immunized group. It provided subsequent protection against virus challenges in the hACE2 transgenic mouse model. Overall, pGX9501 was a promising DNA vaccine candidate against COVID-19, inducing strong humoral immunity and cellular immunity that contributed to the vaccines protective effects.

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Jiang, S., Wu, S., Zhao, G., He, Y., Bao, L., Liu, J., Qin, C., Hou, J., Ding, Y., Wu, J., Yan, J., Humeau, L., Patella, A., Weiner, D. B., Broderick, K., Wang, B.. 2021-08-16. Comparison of Wild Type DNA Sequence of Spike Protein from SARS-CoV-2 with Optimized Sequence on The Induction of Protective Responses Against SARS-Cov-2 Challenge in Mouse Model. https://doi.org/10.1101/2021.08.13.456164

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