TY - JOUR T1 - Optimizing CpG spatial distribution with DNA origami for Th1-polarized therapeutic vaccination JF - bioRxiv DO - 10.1101/2022.06.08.495340 SP - 2022.06.08.495340 AU - Yang C. Zeng AU - Olivia J. Young AU - Christopher M. Wintersinger AU - Frances M. Anastassacos AU - James I. MacDonald AU - Giorgia Isinelli AU - Maxence O. Dellacherie AU - Miguel Sobral AU - Haiqing Bai AU - Amanda R. Graveline AU - Andyna Vernet AU - Melinda Sanchez AU - Kathleen Mulligan AU - Youngjin Choi AU - Thomas C. Ferrante AU - Derin B. Keskin AU - Geoffrey G. Fell AU - Donna Neuberg AU - Catherine J. Wu AU - David J. Mooney AU - Ick Chan Kwon AU - Ju Hee Ryu AU - William M. Shih Y1 - 2022/01/01 UR - http://biorxiv.org/content/early/2022/08/27/2022.06.08.495340.abstract N2 - Multivalent presentation of ligands often enhances receptor activation and downstream signaling. DNA origami offers precise nanoscale spacing of ligands, a potentially useful feature for therapeutic nanoparticles. Here we introduce a “square block” DNA origami platform to explore the importance of spacing of CpG oligonucleotides, which engage Toll-like receptors and thereby act as danger signals for dendritic cells. Through in vitro cell-culture studies and in vivo tumor-treatment models, we demonstrate that square blocks induce Th1 immune polarization when CpG is spaced at 3.5 nm. We observe that this DNA origami vaccine enhances DC activation, antigen cross-presentation, CD8 T cell activation, Th1-polarized CD4 activation and NK cell activation. The vaccine also synergizes effectively with anti-PD-L1 for improved cancer immunotherapy in melanoma and lymphoma models and induces long-term T cell memory. Our results suggest that DNA origami may serve as an advanced vaccine platform for controlling adjuvant spacing and co-delivering antigens.One Sentence Summary This study developed a DNA origami-based cancer vaccine (DoriVac) that co-delivers antigen and CpG immune adjuvant with an optimal spacing for Th1 immune polarization.Competing Interest StatementW.M.S, J.H.R. and Y.C.Z. are inventors on U.S. patent application PCT/US2020/036281 held by Dana-Farber Cancer Institute, Korea Institute of Science & Technology, and Wyss Institute (filed on 6/5/2020) partially based on this work. All other authors declare that they have no competing interests. ER -