title: Improved cell viability of linear polyethylenimine through gamma-cyclodextrin inclusion for effective gene delivery.
abstract: A polypseudorotaxane consisting of a linear polyethylenimine with Mn of 22,000 (LPEI22k) and gamma-cyclodextrins (gamma-CDs; LPEI22k/gamma-CD) has been examined as a gene carrier. The polyplex formation with luciferase-encoding plasmid DNA (pDNA), intracellular trafficking of polyplex, cytotoxicity, and transfection efficiency were evaluated by various characteristic methods. LPEI22k/gamma-CD formed a pDNA polyplex at higher N/P ratios than LPEI22k; this suggests that the gamma-CD threading sterically interfered with the polyplex formation. In addition, the zeta potentials of the polyplex significantly decreased due to the reduction in charge density of LPEI22k caused by gamma-CD threading. The cellular uptake of pDNA in the LPEI22k/gamma-CD polyplex was enhanced by free gamma-CDs released from the polyplex that might accelerate the cellular uptake through enhanced membrane affinity. LPEI22k/gamma-CD significantly increased cell viability even at high N/P ratios, and the polyplex showed high transfection efficacy. The low cytotoxicity and high gene expression of LPEI22k/gamma-CD are advantageous to polyplex administration in vivo.
authors.affiliation: School of Materials Science and the 21st Century COE Program, Japan.
authors.forename: Atsushi
authors.initials: A
authors.lastname: Yamashita
authors.forename: Hak Soo
authors.initials: HS
authors.lastname: Choi
authors.forename: Tooru
authors.initials: T
authors.lastname: Ooya
authors.forename: Nobuhiko
authors.initials: N
authors.lastname: Yui
authors.forename: Hidetaka
authors.initials: H
authors.lastname: Akita
authors.forename: Kentaro
authors.initials: K
authors.lastname: Kogure
authors.forename: Hideyoshi
authors.initials: H
authors.lastname: Harashima
mesh_terms: D000818:Animals; D001692:Biological Transport / Q000502:physiology; D002470:Cell Survival; D004247:DNA / Q000737:chemistry / Q000378:metabolism; D005456:Fluorescent Dyes / Q000378:metabolism; D018014:Gene Transfer Techniques; D015316:Genetic Therapy / Q000379:methods; D046911:Macromolecular Substances; D051379:Mice; D041681:NIH 3T3 Cells; D011094:Polyethyleneimine / Q000737:chemistry* / Q000378:metabolism; D014162:Transfection; D047408:gamma-Cyclodextrins / Q000737:chemistry* / Q000378:metabolism
chemical_list: D005456:Fluorescent Dyes; D046911:Macromolecular Substances; D047408:gamma-Cyclodextrins; D011094:Polyethyleneimine; D004247:DNA