Controlled Release of Poly(U) via Acetalated Dextran Microparticles for Enhanced Vaccine Adjuvant Delivery.

Diverse drug delivery systems are needed to address challenges in delivering novel vaccine components and enhancing their efficacy. Poly(U) is a single-stranded RNA composed of uracil repeats that acts as a toll-like receptor (TLR) 7/8 agonist, stimulating the innate immune system. However, poly(U) is susceptible to ribonuclease degradation without a delivery carrier, and its negative charge hinders cellular uptake.