title: In vivo messenger RNA introduction into the central nervous system using polyplex nanomicelle.
abstract: Messenger RNA (mRNA) introduction is a promising approach to produce therapeutic proteins and peptides without any risk of insertion mutagenesis into the host genome. However, it is difficult to introduce mRNA in vivo mainly because of the instability of mRNA under physiological conditions and its strong immunogenicity through the recognition by Toll-like receptors (TLRs). We used a novel carrier based on self-assembly of a polyethylene glycol (PEG)-polyamino acid block copolymer, polyplex nanomicelle, to administer mRNA into the central nervous system (CNS). The nanomicelle with 50 nm in diameter has a core-shell structure with mRNA-containing inner core surrounded by PEG layer, providing the high stability and stealth property to the nanomicelle. The functional polyamino acids possessing the capacity of pH-responsive membrane destabilization allows smooth endosomal escape of the nanomicelle into the cytoplasm. After introduction into CNS, the nanomicelle successfully provided the sustained protein expression in the cerebrospinal fluid for almost a week. Immune responses after mRNA administration into CNS were effectively suppressed by the use of the nanomicelle compared with naked mRNA introduction. In vitro analyses using specific TLR-expressing HEK293 cells confirmed that the nanomicelle inclusion prevented mRNA from the recognition by TLRs. Thus, the polyplex nanomicelle is a promising system that simultaneously resolved the two major problems of in vivo mRNA introduction, the instability and immunogenicity, opening the door to various new therapeutic strategies using mRNA.
authors: Division of Clinical Biotechnology, Center for Disease Biology and Integrative Medicine, Graduate School of Medicine, The University of Tokyo, Bunkyo-ku, Tokyo, Japan.
authors: Satoshi
authors: S
authors: Uchida
authors: Keiji
authors: K
authors: Itaka
authors: Hirokuni
authors: H
authors: Uchida
authors: Kentaro
authors: K
authors: Hayakawa
authors: Toru
authors: T
authors: Ogata
authors: Takehiko
authors: T
authors: Ishii
authors: Shigeto
authors: S
authors: Fukushima
authors: Kensuke
authors: K
authors: Osada
authors: Kazunori
authors: K
authors: Kataoka
mesh_terms: D000596:Amino Acids / Q000737:chemistry; D000818:Animals; D045744:Cell Line, Tumor; D002490:Central Nervous System / Q000378:metabolism*; D005260:Female; D015870:Gene Expression; D049452:Green Fluorescent Proteins / Q000235:genetics / Q000378:metabolism; D057809:HEK293 Cells; D006801:Humans; D007278:Injections, Spinal; D008156:Luciferases / Q000235:genetics / Q000378:metabolism; D051379:Mice; D008807:Mice, Inbred BALB C; D008823:Micelles; D008856:Microscopy, Fluorescence; D049329:Nanostructures / Q000008:administration & dosage / Q000737:chemistry; D011092:Polyethylene Glycols / Q000737:chemistry; D011108:Polymers / Q000737:chemistry; D012333:RNA, Messenger / Q000008:administration & dosage* / Q000737:chemistry / Q000235:genetics*; D051381:Rats; D017207:Rats, Sprague-Dawley; D020133:Reverse Transcriptase Polymerase Chain Reaction; D051199:Toll-Like Receptor 7 / Q000235:genetics / Q000378:metabolism; D051217:Toll-Like Receptor 9 / Q000235:genetics / Q000378:metabolism
chemical_list: D000596:Amino Acids; D008823:Micelles; D011108:Polymers; D012333:RNA, Messenger; D051199:Toll-Like Receptor 7; D051217:Toll-Like Receptor 9; D049452:Green Fluorescent Proteins; D011092:Polyethylene Glycols; D008156:Luciferases