title: Intracellular delivery of proteins into mammalian living cells by polyethylenimine-cationization.
abstract: In the post-genomic era, there is pressing need for development of protein manipulation methodology to analyze functions of proteins in living cells. For this purpose, techniques to deliver functional proteins into living cells are currently being evaluated as alternative approaches to the introduction of transcriptionally active DNA. Here, we describe a novel method for efficient protein transduction into living cells in which a protein is simply cationized with polyethylenimine (PEI) by limited chemical conjugation. PEI-cationized proteins appear to adhere to the cell surface by ionic charge interaction and then internalize into cells in a receptor- and transporter-independent fashion. Since PEI is an organic macromolecule with a high cationic-charge density, limited coupling with PEI results in endowment of sufficient cationic charge to proteins without causing serious decline in their fundamental functions. A number of PEI-cationized proteins, such as ribonuclease (RNase), green fluorescent protein (GFP) and immunoglobulin (IgG), efficiently entered cells and functioned in the cytosol. Our results suggest that protein cationization techniques using PEI will be useful for the development of protein transduction technology.
authors.affiliation: Department of Bioscience and Biotechnology, Faculty of Engineering, Graduate School of Natural Science and Technology, Okayama University, Okayama 700-8530, Japan.
authors.forename: Junichiro
authors.initials: J
authors.lastname: Futami
authors.forename: Midori
authors.initials: M
authors.lastname: Kitazoe
authors.forename: Takashi
authors.initials: T
authors.lastname: Maeda
authors.forename: Emiko
authors.initials: E
authors.lastname: Nukui
authors.forename: Masakiyo
authors.initials: M
authors.lastname: Sakaguchi
authors.forename: Jun
authors.initials: J
authors.lastname: Kosaka
authors.forename: Masahiro
authors.initials: M
authors.lastname: Miyazaki
authors.forename: Megumi
authors.initials: M
authors.lastname: Kosaka
authors.forename: Hiroko
authors.initials: H
authors.lastname: Tada
authors.forename: Masaharu
authors.initials: M
authors.lastname: Seno
authors.forename: Junzo
authors.initials: J
authors.lastname: Sasaki
authors.forename: Nam-Hu
authors.initials: NH
authors.lastname: Huh
authors.forename: Masayoshi
authors.initials: M
authors.lastname: Namba
authors.forename: Hidenori
authors.initials: H
authors.lastname: Yamada
mesh_terms: D016475:3T3 Cells; D000818:Animals; D002412:Cations; D004058:Diffusion; D016503:Drug Delivery Systems / Q000379:methods*; D004705:Endocytosis / Q000502:physiology*; D007274:Injections, Intraperitoneal; D007424:Intracellular Fluid / Q000737:chemistry* / Q000378:metabolism*; D007668:Kidney / Q000737:chemistry / Q000378:metabolism; D008099:Liver / Q000737:chemistry / Q000378:metabolism; D008657:Metabolic Clearance Rate; D051379:Mice; D008810:Mice, Inbred C57BL; D009928:Organ Specificity; D011094:Polyethyleneimine / Q000737:chemistry*; D021381:Protein Transport / Q000502:physiology; D011506:Proteins / Q000008:administration & dosage / Q000737:chemistry* / Q000493:pharmacokinetics*; D055672:Static Electricity
chemical_list: D002412:Cations; D011506:Proteins; D011094:Polyethyleneimine