title: Construction and delivery of tissue-engineered human retinal pigment epithelial cell sheets, using magnetite nanoparticles and magnetic force.
abstract: Choroidal neovascularization (CNV) is the most severe form of age-related macular degeneration (AMD), which causes rapid visual loss. Transplantation of cultured retinal pigment epithelium (RPE) cell sheet by tissue engineering is a possible approach to the treatment of CNV. In the present study, we investigated the possibility of using magnetite nanoparticles and magnetic force to construct and deliver RPE cell sheets in vitro. When magnetite cationic liposomes (MCLs), having a positive charge at the surface, were added to ARPE-19 human RPE cells at a concentration of 25 or 50 pg of magnetite per cell, the cells took up 40 to 55% of the MCLs. The magnetically labeled ARPE-19 cells (8 x 10(3) cells/mm(2), which corresponds to 10-fold the confluent concentration against the culture area [4 mm(2)]) were seeded into an ultra-low-attachment plate and a magnet (4000 G) was placed under the well. The magnetically labeled ARPE-19 cells formed an approximately 15-layered cell sheet after a 24 h of culture. When the magnet was removed, the sheets were detached from the bottom of the plate and then harvested and transferred to a tissue culture dish, using a magnet. Subsequently, the cell sheets were attached onto the dish, and the cells growing on the sheets were observed. This novel methodology, termed "magnetic force-based tissue engineering" (Mag-TE), is a possible approach for CNV treatment.
authors.affiliation: Department of Biotechnology, School of Engineering, Nagoya University, Japan.
authors.forename: Akira
authors.initials: A
authors.lastname: Ito
authors.forename: Eri
authors.initials: E
authors.lastname: Hibino
authors.forename: Chiaki
authors.initials: C
authors.lastname: Kobayashi
authors.forename: Hiroko
authors.initials: H
authors.lastname: Terasaki
authors.forename: Hideaki
authors.initials: H
authors.lastname: Kagami
authors.forename: Minoru
authors.initials: M
authors.lastname: Ueda
authors.forename: Takeshi
authors.initials: T
authors.lastname: Kobayashi
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Honda
mesh_terms: D001705:Bioprosthesis; D002448:Cell Adhesion / Q000502:physiology; D018929:Cell Culture Techniques / Q000379:methods*; D002460:Cell Line; D002465:Cell Movement / Q000502:physiology; D016764:Cell Polarity / Q000502:physiology; D002478:Cells, Cultured; D005240:Feasibility Studies; D006801:Humans; D018189:Immunomagnetic Separation / Q000379:methods*; D008280:Magnetics; D008846:Micromanipulation / Q000379:methods*; D043942:Nanotubes; D010857:Pigment Epithelium of Eye / Q000166:cytology* / Q000502:physiology* / Q000637:transplantation; D013194:Staining and Labeling / Q000379:methods; D013314:Stress, Mechanical; D023822:Tissue Engineering / Q000379:methods*