Hakim, Chady H.Kumar, Sandeep R. P.Pérez-López, Dennis O.Wasala, Nalinda B.Zhang, DongYue, YongpingTeixeira, JamesZhang, KeqingMillion, Emily D.Nelson, Christopher E.Metzger, SamanthaHan, JinLouderman, Jacqueline A.Schmidt, FlorianFeng, FengGrimm, DirkSmith, Bruce F.Yao, GangYang, N. NoraGersbach, Charles A.Chen, Shi-jieHerzog, Roland W.Duan, Dongsheng2024-04-242024-04-242021-11-24Hakim CH, Kumar SRP, Pérez-López DO, et al. Cas9-specific immune responses compromise local and systemic AAV CRISPR therapy in multiple dystrophic canine models. Nat Commun. 2021;12(1):6769. Published 2021 Nov 24. doi:10.1038/s41467-021-26830-7https://hdl.handle.net/1805/40175Adeno-associated virus (AAV)-mediated CRISPR-Cas9 editing holds promise to treat many diseases. The immune response to bacterial-derived Cas9 has been speculated as a hurdle for AAV-CRISPR therapy. However, immunological consequences of AAV-mediated Cas9 expression have thus far not been thoroughly investigated in large mammals. We evaluate Cas9-specific immune responses in canine models of Duchenne muscular dystrophy (DMD) following intramuscular and intravenous AAV-CRISPR therapy. Treatment results initially in robust dystrophin restoration in affected dogs but also induces muscle inflammation, and Cas9-specific humoral and cytotoxic T-lymphocyte (CTL) responses that are not prevented by the muscle-specific promoter and transient prednisolone immune suppression. In normal dogs, AAV-mediated Cas9 expression induces similar, though milder, immune responses. In contrast, other therapeutic (micro-dystrophin and SERCA2a) and reporter (alkaline phosphatase, AP) vectors result in persistent expression without inducing muscle inflammation. Our results suggest Cas9 immunity may represent a critical barrier for AAV-CRISPR therapy in large mammals.en-USAttribution 4.0 InternationalNeuromuscular diseaseCRISPR-Cas9 genome editingDuchenne muscular dystrophyArticle