DNA origami vaccine (DoriVac) nanoparticles improve both humoral and cellular immune responses to infectious diseases

Current SARS-CoV-2 vaccines have demonstrated robust induction of neutralizing antibodies and CD4+ T cell activation, however CD8+ responses are variable, and the duration of immunity and protection against variants are limited. Here we repurposed our DNA origami vaccine nanotechnology, DoriVac, for targeting infectious viruses, namely SARS-CoV-2, HIV, and Ebola. The DNA origami nanoparticle, conjugated with infectious-disease-specific heptad repeat 2 (HR2) peptides, which act as highly conserved antigens, and CpG adjuvant at precise nanoscale spacing, induced neutralizing antibodies, Th1 CD4+ T cells, and CD8+ T cells in naive mice, with significant improvement over a bolus control. Pre-clinical studies using lymph-node-on-a-chip systems validated that DoriVac, when conjugated with antigenic peptides or proteins, induced promising cellular and humoral immune responses in human cells. Moreover, DoriVac bearing full-length SARS-CoV-2 spike protein achieved immune responses comparable to current mRNA vaccine platforms while potentially reducing storage constraints. These results suggest that DoriVac holds potential as a versatile, modular vaccine platform, capable of inducing both humoral and cellular immunities, underscoring its potential utility in addressing future pandemics.