SARS-CoV-2 Vaccines Elicit Durable Immune Responses in Infant Rhesus Macaques

Garrado, C. G.; Curtis, A. D.; Dennis, M.; Pathak, S. H.; Gao, H.; Montefiori, D.; Tomai, M.; Fox, C. B.; Kozlowski, P. A.; Scobey, T.; Munt, J. E.; Mallory, M. L.; Saha, P. T.; Hudgens, M. G.; Lindesmith, L. C.; Baric, R. S.; Abiona, O. M.; Corbett, K. S.; Edwards, D.; Carfi, A.; Fouda, G.; Van Rompay, K. K. A.; De Paris, K.; Permar, S. R.

doi:10.1101/2021.04.05.438479

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bioRxiv · 10.1101/2021.04.05.438479

SARS-CoV-2 Vaccines Elicit Durable Immune Responses in Infant Rhesus Macaques

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Abstract

Early life SARS-CoV-2 vaccination has the potential to provide lifelong protection and achieve herd immunity. To evaluate SARS-CoV-2 infant vaccination, we immunized two groups of 8 infant rhesus macaques (RMs) at weeks 0 and 4 with stabilized prefusion SARS-CoV-2 S-2P spike (S) protein, either encoded by mRNA encapsulated in lipid nanoparticles (mRNA-LNP) or mixed with 3M-052-SE, a TLR7/8 agonist in a squalene emulsion (Protein+3M-052-SE). Neither vaccine induced adverse effects. High magnitude S-binding IgG and neutralizing infectious dose 50 (ID50) >103 were elicited by both vaccines. S-specific T cell responses were dominated by IL-17, IFN-{gamma}, or TNF-. Antibody and cellular responses were stable through week 22. The S-2P mRNA-LNP and Protein-3M-052-SE vaccines are promising pediatric SARS-CoV-2 vaccine candidates to achieve durable protective immunity. One-Sentence SummarySARS-CoV-2 vaccines are well-tolerated and highly immunogenic in infant rhesus macaques

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Garrado, C. G., Curtis, A. D., Dennis, M., Pathak, S. H., Gao, H., Montefiori, D., Tomai, M., Fox, C. B., Kozlowski, P. A., Scobey, T., Munt, J. E., Mallory, M. L., Saha, P. T., Hudgens, M. G., Lindesmith, L. C., Baric, R. S., Abiona, O. M., Corbett, K. S., Edwards, D., Carfi, A., Fouda, G., Van Rompay, K. K. A., De Paris, K., Permar, S. R.. 2021-04-06. SARS-CoV-2 Vaccines Elicit Durable Immune Responses in Infant Rhesus Macaques. https://doi.org/10.1101/2021.04.05.438479

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