AAV8-mediated CasRx delivery and expression in the cochlea and cochlear nucleus of mice

CRISPR/Cas9-based genome editing has made substantial progress in recent years and has enabled the treatment of a variety of genetic diseases, including hearing loss in congenitally deaf mice. However, successful gene editing for hereditary deafness may still induce off-target mutations in genomic DNA, which limits its clinical translation. CasRx, also known as RfxCas13d, is a compact RNA-targeting CRISPR effector that can be packaged into AAV vectors for in vivo delivery. CasRx, a recently identified member of the type VI CRISPR system, modulates target RNA expression without altering DNA sequences, thereby avoiding permanent off-target mutations and offering broad therapeutic potential. Here, we used adeno-associated virus serotype 8 (AAV8) to deliver CasRx into the cochlea and cochlear nucleus (CN) of C57BL/6J mice and evaluated its expression pattern and short-term safety. Two weeks after viral injection, the number and morphology of neurons and other cell types in the CN remained normal. Importantly, auditory brainstem response (ABR) thresholds were unchanged after viral delivery, indicating that AAV8-mediated CasRx expression did not detectably impair auditory function during the short observation period. In conclusion, this study demonstrates the feasibility and short-term safety of AAV8-mediated CasRx delivery and expression in the cochlea and cochlear nucleus, providing a delivery platform for future guide RNA-directed transcript-modulation studies in auditory disorders.

Abstract from PubMed Central (PMID 43022808, PMC13756184). This entry was added automatically by our daily literature monitor because it matches the topics we follow; read the full paper at the original source.