Lymph node-targeted DNA engages TBK1/IFN-I-driven innate immunity to induce potent T cell responses and durable memory in mice and NHPs.

Adjuvants are immunoactivators capable of shaping the magnitude and quality of antigen-specific immune responses induced by subunit immunization. Presently, there is an acute need for effective adjuvants that safely induce durable and balanced humoral and cellular responses. Here, we engineered a class of Amphiphile (AMP)-modified, immunostimulatory DNA adjuvants designed for targeted delivery to lymph nodes and enhanced stimulation of TANK-binding kinase 1 (TBK1)-mediated danger-sensing pathways to generate strong adaptive immunity and long-term memory with potent recall potential. AMP-DNA adjuvants induced robust interferon type-I (IFN-I)-driven inflammatory environments in mouse and nonhuman primate (NHP) lymph nodes, leading to significantly enhanced cytokine secretion by polyfunctional CD8+ and CD4+ T cells in multiple tissues, as well as strongly elevated T helper cell 1 (TH1)-associated and neutralizing antibody responses, in the absence of systemic toxicity. These results demonstrate that AMP modification enables lymph node-targeted DNA adjuvants to potently activate IFN-I signaling to generate substantial cellular and humoral responses crucial for vaccine efficacy.