Crosslinked ionizable lipids reprogram dendritic cell metabolism for potent mRNA vaccination.

Modulating metabolism in immune cells is an effective approach to induce desired immune responses. Here we develop a lipid nanoparticle (LNP) capable of metabolic reprogramming of dendritic cells for mRNA vaccine applications. Using imidoester-based conjugation chemistry, we design a crosslinked ionizable lipid, C12-2aN, which possesses intrinsic metabolic modulatory properties. This multifunctional ionizable lipid not only promotes effective mRNA expression by facilitating endosomal escape but also stimulates glycolysis through mTORC2 pathway activation. As both an mRNA carrier and a metabolic modulator, C12-2aN LNPs lead to potent vaccine efficacy in both SARS-CoV-2 and OVA cancer vaccine models, resulting in stronger neutralization of pseudovirus infection and improved survival rates, respectively, compared with control LNPs without the crosslinker. Moreover, C12-2aN LNPs outperformed FDA-approved LNPs in terms of reduced off-target delivery and lower immunogenicity. Overall, the integration of mRNA delivery and metabolic reprogramming induced by the ionizable lipid component presents significant potential for next-generation mRNA LNP vaccines.