DNA origami vaccine nanoparticles improve humoral and cellular immune responses to infectious diseases

Current SARS-CoV-2 (severe acute respiratory syndrome coronavirus 2) vaccines have shown 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 repurpose our DNA origami vaccine nanotechnology DoriVac to target infectious viruses, namely, SARS-CoV-2, HIV and Ebola. The DNA origami nanoparticle, conjugated with infectious-disease-specific heptad repeat 2 peptides, which act as highly conserved antigens, and CpG adjuvant at precise nanoscale spacing, induces 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 validate that DoriVac, when conjugated with antigenic peptides or proteins, induces promising cellular and humoral immune responses in human cells. Moreover, DoriVac bearing full-length SARS-CoV-2 spike protein achieves 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 future use.