Allele-Selective Suppression of Mutant Huntingtin in Primary Human Blood Cells
AuthorsMiller, James R. C.
Pfister, Edith L.
Kennington, Lori A.
Ostroff, Gary R.
Tabrizi, Sarah J.
UMass Chan AffiliationsProgram in Molecular Medicine
RNA Therapeutics Institute
Department of Medicine
Document TypeJournal Article
KeywordsDiseases of the nervous system
Innate immune cells
Immunoprophylaxis and Therapy
Nervous System Diseases
MetadataShow full item record
AbstractPost-transcriptional gene silencing is a promising therapy for the monogenic, autosomal dominant, Huntington's disease (HD). However, wild-type huntingtin (HTT) has important cellular functions, so the ideal strategy would selectively lower mutant HTT while sparing wild-type. HD patients were genotyped for heterozygosity at three SNP sites, before phasing each SNP allele to wild-type or mutant HTT. Primary ex vivo myeloid cells were isolated from heterozygous patients and transfected with SNP-targeted siRNA, using glucan particles taken up by phagocytosis. Highly selective mRNA knockdown was achieved when targeting each allele of rs362331 in exon 50 of the HTT transcript; this selectivity was also present on protein studies. However, similar selectivity was not observed when targeting rs362273 or rs362307. Furthermore, HD myeloid cells are hyper-reactive compared to control. Allele-selective suppression of either wild-type or mutant HTT produced a significant, equivalent reduction in the cytokine response of HD myeloid cells to LPS, suggesting that wild-type HTT has a novel immune function. We demonstrate a sequential therapeutic process comprising genotyping and mutant HTT-linkage of SNPs, followed by personalised allele-selective suppression in a small patient cohort. We further show that allele-selectivity in ex vivo patient cells is highly SNP-dependent, with implications for clinical trial target selection.
SourceSci Rep. 2017 Apr 24;7:46740. doi: 10.1038/srep46740. Link to article on publisher's site
Permanent Link to this Itemhttp://hdl.handle.net/20.500.14038/40335
RightsCopyright © 2017, The Author(s)