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bioRxiv · 10.1101/2025.03.20.644395

Combining a rhesus cytomegalovirus/SIV vaccine with neutralizing antibody to protect against SIV challenge in rhesus macaques

Abstract

A vaccine is widely regarded as necessary for the control of the HIV pandemic and eventual eradication of AIDS. Neutralizing antibodies and MHC-E-restricted CD8+ T cells have both been shown capable of vaccine protection against the simian counterpart of HIV, SIV, in rhesus macaques. Here we provide preliminary evidence that combining these orthogonal antiviral mechanisms can provide increased protection against SIV challenge such that replication arrest observed following vaccination with a rhesus cytomegalovirus (RhCMV/SIV)-based vaccine was enhanced in the presence of passively administered incompletely protective levels of neutralizing antibody. The report invites studies involving larger cohorts of macaques and alternate routes of providing neutralizing antibody.

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BibTeXRIS

Coppola, J., Parren, M., Bastidas, R., Saye-Francisco, K., Malvin, J., Jardine, J. G., Gilbride, R. M., Ojha, S., Feltham, S., Morrow, D., Barber-Axthelm, A., Bochart, R., Fast, R., Oswald, K., Shoemaker, R., Lifson, J. D., Picker, L. J., Burton, D. R., Hansen, S. G.. 2025-03-25. Combining a rhesus cytomegalovirus/SIV vaccine with neutralizing antibody to protect against SIV challenge in rhesus macaques. https://doi.org/10.1101/2025.03.20.644395

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