Researchers at the University of Pennsylvania reported a redesign of ionizable lipids that produced aromatic, bioreducible LNPs (aroLNPs) which reduce liver accumulation and enhance delivery to lymph nodes in mice. The best aroLNP formulations sent roughly tenfold less mRNA to the liver while maintaining lymph node tropism, improving antigen presentation at immune training sites. The study, published in JACS, used aromatic scaffolds and disulfide bonds for biodegradability; lymph node‑targeted delivery could boost vaccine potency and reduce systemic side effects.