title: Influence of cationic lipid composition on gene silencing properties of lipid nanoparticle formulations of siRNA in antigen-presenting cells.
abstract: Lipid nanoparticles (LNPs) are currently the most effective in vivo delivery systems for silencing target genes in hepatocytes employing small interfering RNA. Antigen-presenting cells (APCs) are also potential targets for LNP siRNA. We examined the uptake, intracellular trafficking, and gene silencing potency in primary bone marrow macrophages (bmMΦ) and dendritic cells of siRNA formulated in LNPs containing four different ionizable cationic lipids namely DLinDAP, DLinDMA, DLinK-DMA, and DLinKC2-DMA. LNPs containing DLinKC2-DMA were the most potent formulations as determined by their ability to inhibit the production of GAPDH target protein. Also, LNPs containing DLinKC2-DMA were the most potent intracellular delivery agents as indicated by confocal studies of endosomal versus cytoplamic siRNA location using fluorescently labeled siRNA. DLinK-DMA and DLinKC2-DMA formulations exhibited improved gene silencing potencies relative to DLinDMA but were less toxic. In vivo results showed that LNP siRNA systems containing DLinKC2-DMA are effective agents for silencing GAPDH in APCs in the spleen and peritoneal cavity following systemic administration. Gene silencing in APCs was RNAi mediated and the use of larger LNPs resulted in substantially reduced hepatocyte silencing, while similar efficacy was maintained in APCs. These results are discussed with regard to the potential of LNP siRNA formulations to treat immunologically mediated diseases.
authors.affiliation: NanoMedicine Research Group, Department of Biochemistry and Molecular Biology Life Sciences Institute, University of British Columbia, Vancouver, British Columbia, Canada. gbasha@mail.ubc.ca
authors.forename: Genc
authors.initials: G
authors.lastname: Basha
authors.forename: Tatiana I
authors.initials: TI
authors.lastname: Novobrantseva
authors.forename: Nicole
authors.initials: N
authors.lastname: Rosin
authors.forename: Yuen Yi C
authors.initials: YY
authors.lastname: Tam
authors.forename: Ismail M
authors.initials: IM
authors.lastname: Hafez
authors.forename: Matthew K
authors.initials: MK
authors.lastname: Wong
authors.forename: Tsukasa
authors.initials: T
authors.lastname: Sugo
authors.forename: Vera M
authors.initials: VM
authors.lastname: Ruda
authors.forename: June
authors.initials: J
authors.lastname: Qin
authors.forename: Boris
authors.initials: B
authors.lastname: Klebanov
authors.forename: Marco
authors.initials: M
authors.lastname: Ciufolini
authors.forename: Akin
authors.initials: A
authors.lastname: Akinc
authors.forename: Ying K
authors.initials: YK
authors.lastname: Tam
authors.forename: Michael J
authors.initials: MJ
authors.lastname: Hope
authors.forename: Pieter R
authors.initials: PR
authors.lastname: Cullis
mesh_terms: D000818:Animals; D000938:Antigen-Presenting Cells / Q000378:metabolism*; D015153:Blotting, Western; D001853:Bone Marrow; D002412:Cations / Q000737:chemistry*; D002478:Cells, Cultured; D003713:Dendritic Cells / Q000166:cytology / Q000378:metabolism; D004705:Endocytosis; D005434:Flow Cytometry; D020868:Gene Silencing; D005987:Glyceraldehyde-3-Phosphate Dehydrogenases / Q000037:antagonists & inhibitors* / Q000235:genetics / Q000378:metabolism; D022781:Hepatocytes / Q000166:cytology / Q000378:metabolism; D017493:Leukocyte Common Antigens / Q000037:antagonists & inhibitors / Q000235:genetics / Q000378:metabolism; D008055:Lipids / Q000008:administration & dosage*; D008081:Liposomes; D008099:Liver / Q000378:metabolism; D008264:Macrophages / Q000166:cytology / Q000378:metabolism; D051379:Mice; D008810:Mice, Inbred C57BL; D053758:Nanoparticles / Q000008:administration & dosage* / Q000737:chemistry; D034622:RNA Interference; D034741:RNA, Small Interfering / Q000008:administration & dosage* / Q000235:genetics
chemical_list: D002412:Cations; D008055:Lipids; D008081:Liposomes; D034741:RNA, Small Interfering; D005987:Glyceraldehyde-3-Phosphate Dehydrogenases; D017493:Leukocyte Common Antigens; C516770:Ptprc protein, mouse