An RNA-targeting CRISPR–Cas13d system alleviates disease-related phenotypes in Huntington’s disease models

• DOI: 10.1038/s41593-022-01207-1
• Publication Date: 2022-12-12T17:06:28Z
• Authors: Kathryn H. Morelli; Qian Wu; Maya L. Gosztyla; Hongshuai Liu; Minmin Yao; Chuangchuang Zhang; Jiaxu Chen; Ryan J. Marina; Kari Lee; Krysten L. Jones; Megan Y. Huang; Allison Li; Charlene Smith-Ge...; Leslie M. Thompson; Wenzhen Duan; Gene W. Yeo
• Keywords: Huntington's Disease; 0301 basic medicine; Medical Biotechnology; Messenger; 610; Neurodegenerative; Article; Mice; 03 medical and health sciences; Rare Diseases; Genetics; 2.1 Biological and endogenous factors; Psychology; Animals; Clustered Regularly Interspaced Short Palindromic Repeats; RNA, Messenger; Huntingtin Protein; Neurology & Neurosurgery; Biomedical and Clinical Sciences; Stem Cell Research - Induced Pluripotent Stem Cell - Human; Stem Cell Research - Induced Pluripotent Stem Cell; 5.2 Cellular and gene therapies; Animal; Neurosciences; 540; Stem Cell Research; Corpus Striatum; 3. Good health; Brain Disorders; Disease Models, Animal; Orphan Drug; Huntington Disease; Phenotype; Neurological; Disease Models; Biological psychology; RNA; Cognitive Sciences

AbstractHuntington’s disease (HD) is a fatal, dominantly inherited neurodegenerative disorder caused by CAG trinucleotide expansion in exon 1 of the huntingtin (HTT) gene. Since the reduction of pathogenic mutant HTT messenger RNA is therapeutic, we developed a mutant allele-sensitive CAGEX RNA-targeting CRISPR–Cas13d system (Cas13d–CAGEX) that eliminates toxic CAGEX RNA in fibroblasts derived from patients with HD and induced pluripotent stem cell-derived neurons. We show that intrastriatal delivery of Cas13d–CAGEX via an adeno-associated viral vector selectively reduces mutant HTT mRNA and protein levels in the striatum of heterozygous zQ175 mice, a model of HD. This also led to improved motor coordination, attenuated striatal atrophy and reduction of mutant HTT protein aggregates. These phenotypic improvements lasted for at least eight months without adverse effects and with minimal off-target transcriptomic effects. Taken together, we demonstrate proof of principle of an RNA-targeting CRISPR–Cas13d system as a therapeutic approach for HD, a strategy with implications for the treatment of other dominantly inherited disorders.