DNA origami vaccines program antigen-focused germinal centers
Anna Romanov, Grant A. Knappe, Larance Ronsard, Christopher A. Cottrell, Yiming J. Zhang, Heikyung Suh, Lauren Duhamel, Marjan Omer, Asheley P. Chapman, Katie Spivakovsky, Patrick Skog, Claudia T. Flynn, Jeong Hyun Lee, Kalyuzhniy Oleksandr, Alessia Liguori, Molly F. Parsons, Vanessa Lewis, Josue Canales, Boris Reizis, Ryan Tingle, Torben Schiffner, William R. Schief, Daniel Lingwood, Mark Bathe, DJ Irvine
Abstract
Priming rare subdominant precursor B cells in germinal centers (GCs) is a central goal of vaccination to generate broadly neutralizing antibodies (bnAbs) against HIV. Multivalent immunogen display on protein nanoparticle scaffolds can promote such responses, but it also generates scaffold-specific B cells that could theoretically limit bnAb precursor expansion in GCs. We rationally designed DNA origami-based virus-like particles (DNA-VLPs) displaying a germline-targeting HIV envelope protein immunogen, which elicited no scaffold-specific antibody responses. Compared with a state-of-the-art clinical protein nanoparticle, these DNA-VLPs increased the expansion of epitope-specific GC B cells relative to off-target B cells and enhanced expansion of bnAb-lineage B cells in a humanized mouse model of CD4 binding site priming. Thus, minimizing off-target responses enhances bnAb priming and indicates that DNA-VLPs are a promising vaccine platform.