A Smart DNA-based Nanosystem Containing Ribosome-Regulating Sirna for Enhanced Mrna Transfection.

Abstract

Messenger RNA (mRNA) transfection is the prerequisite for the application of mRNA-based therapeutics. In hard-to-transfect cells, such as macrophages, the effective transfection of mRNA remains a long-standing challenge. Herein, we report a smart DNA-based nanosystem containing ribosome biogenesis-promoting siRNA, realizing efficient mRNA transfection in macrophages. Four monomers were copolymerized to form nanoframework (NF), including N-isopropylacrylamide (NIPAM) as skeleton, and Acrydite-DNA as initiator to trigger the cascade assembly of DNA hairpins (H1-polyT and H2-siRNA). By virtue of the phase transition characteristic of polymeric NIPAM, below the lower critical solution temperature (LCST, ∼34°C), NF swelled to expose polyT sequences to hybridize with the polyA tail of mRNA. Above the LCST, NF de-swelled to encapsulate mRNA. The disulfide bond in NF responded to glutathione, triggering the disassembly of the nanosystem; the siRNA and mRNA were released in response to triphosadenine and RNase H. The siRNA down-regulated the expression of heat shock protein 27, which up-regulated the expression of phosphorylated ribosomal protein S6. Our nanosystem showed satisfactory mRNA transfection and translation efficiency in a mouse model. We envision that our DNA-based nanosystem provides a promising carrier to deliver mRNA in hard-to-transfect cells, and promotes the development of mRNA-based therapeutics. This article is protected by copyright. All rights reserved.