CRISPR/Cas9 delivery by NIR-responsive biomimetic nanoparticles for targeted HBV therapy

Background: Currently, there are no curative drugs for hepatitis B virus (HBV). Complete elimination of HBV covalently closed circular DNA (cccDNA) is key to the complete cure of hepatitis B virus infection. The CRISPR/Cas9 system can directly destroy HBV cccDNA. However, a CRISPR/Cas9 delivery system with low immunogenicity and high efficiency has not yet been established. Moreover, effective implementation of precise remote spatiotemporal operations in CRISPR/Cas9 is a major limitation. Results: In this work, we designed NIR-responsive biomimetic nanoparticles (UCNPs-Cas9@CM), which could effectively deliver Cas9 RNP to achieve effective genome editing for HBV therapy. HBsAg, HBeAg, HBV pgRNA and HBV DNA along with cccDNA in HBV-infected cells were found to be inhibited. These findings were confirmed in HBV-Tg mice, which did not exhibit significant cytotoxicity and minimal off-target DNA damage. Conclusions: The UCNPs-based biomimetic nanoplatforms achieved the inhibition of HBV replication via CRISPR therapy and it is a potential system for efficient treatment of human HBV diseases.