title: Intrathecal delivery of frataxin mRNA encapsulated in lipid nanoparticles to dorsal root ganglia as a potential therapeutic for Friedreich's ataxia.
abstract: In Friedreich's ataxia (FRDA) patients, diminished frataxin (FXN) in sensory neurons is thought to yield the predominant pathology associated with disease. In this study, we demonstrate successful usage of RNA transcript therapy (RTT) as an exogenous human FXN supplementation strategy in vitro and in vivo, specifically to dorsal root ganglia (DRG). Initially, 293 T cells were transfected with codon optimized human FXN mRNA, which was translated to yield FXN protein. Importantly, FXN was rapidly processed into the mature functional form of FXN (mFXN). Next, FXN mRNA, in the form of lipid nanoparticles (LNPs), was administered intravenously in adult mice. Examination of liver homogenates demonstrated efficient FXN LNP uptake in hepatocytes and revealed that the mitochondrial maturation machinery had efficiently processed all FXN protein to mFXN in ~24 h in vivo. Remarkably, greater than 50% mFXN protein derived from LNPs was detected seven days after intravenous administration of FXN LNPs, suggesting that the half-life of mFXN in vivo exceeds one week. Moreover, when FXN LNPs were delivered by intrathecal administration, we detected recombinant human FXN protein in DRG. These observations provide the first demonstration that RTT can be used for the delivery of therapeutic mRNA to DRG.
authors.affiliation: Rare Disease Research Unit, Pfizer, 610 Main Street, Cambridge, MA 02139, USA.
authors.forename: Joseph F
authors.initials: JF
authors.lastname: Nabhan
authors.affiliation: Global Biotherapeutics, Pfizer, 610 Main Street, Cambridge, MA 02139, USA.
authors.forename: Kristy M
authors.initials: KM
authors.lastname: Wood
authors.affiliation: Comparative Medicine, Pfizer, 1 Burtt Rd, Andover, MA 01810, USA.
authors.forename: Varada P
authors.initials: VP
authors.lastname: Rao
authors.affiliation: Comparative Medicine, Pfizer, 1 Burtt Rd, Andover, MA 01810, USA.
authors.forename: Jeffrey
authors.initials: J
authors.lastname: Morin
authors.affiliation: Drug Safety Research and Development, Pfizer, 1 Burtt Rd, Andover, MA 01810, USA.
authors.forename: Surya
authors.initials: S
authors.lastname: Bhamidipaty
authors.affiliation: Drug Safety Research and Development, Pfizer, 1 Burtt Rd, Andover, MA 01810, USA.
authors.forename: Timothy P
authors.initials: TP
authors.lastname: LaBranche
authors.affiliation: Rare Disease Research Unit, Pfizer, 610 Main Street, Cambridge, MA 02139, USA.
authors.forename: Renea L
authors.initials: RL
authors.lastname: Gooch
authors.affiliation: Rare Disease Research Unit, Pfizer, 610 Main Street, Cambridge, MA 02139, USA.
authors.forename: Fazli
authors.initials: F
authors.lastname: Bozal
authors.affiliation: Rare Disease Research Unit, Pfizer, 610 Main Street, Cambridge, MA 02139, USA.
authors.forename: Christine E
authors.initials: CE
authors.lastname: Bulawa
authors.affiliation: Global Biotherapeutics, Pfizer, 610 Main Street, Cambridge, MA 02139, USA.
authors.forename: Braydon C
authors.initials: BC
authors.lastname: Guild
mesh_terms: D000818:Animals; D004195:Disease Models, Animal; D005260:Female; D005621:Friedreich Ataxia / Q000175:diagnosis / Q000235:genetics* / Q000378:metabolism / Q000628:therapy; D005727:Ganglia, Spinal / Q000378:metabolism*; D015870:Gene Expression; D017930:Genes, Reporter; D006801:Humans; D007278:Injections, Spinal; D033862:Iron-Binding Proteins / Q000235:genetics* / Q000378:metabolism; D008055:Lipids / Q000737:chemistry; D008099:Liver / Q000378:metabolism; D008163:Luminescent Measurements; D051379:Mice; D057054:Molecular Imaging; D053758:Nanoparticles / Q000008:administration & dosage / Q000737:chemistry; D014176:Protein Biosynthesis; D012333:RNA, Messenger / Q000008:administration & dosage / Q000737:chemistry; D015398:Signal Transduction; D014162:Transfection; D000096923:Frataxin
chemical_list: D033862:Iron-Binding Proteins; D008055:Lipids; D012333:RNA, Messenger; D000096923:Frataxin