Pleiotropic functions of magnetic nanoparticles for ex vivo gene transfer.
Gene transfer technique has various applications, ranging from cellular biology to medical treatments for diseases. Although nonviral vectors, such as episomal vectors, have been developed, it is necessary to improve their gene transfer efficacy. Therefore, we attempted to develop a highly efficient gene delivery system combining an episomal vector with magnetic nanoparticles (MNPs). In comparison with the conventional method using transfection reagents, polyethylenimine-coated MNPs introduced episomal vectors more efficiently under a magnetic field and could express the gene in mammalian cells with higher efficiency and for longer periods. This novel in vitro separation method of gene-introduced cells utilizing the magnetic property of MNPs significantly facilitated the separation of cells of interest. Transplanted cells in vivo were detected using magnetic resonance. These results suggest that MNPs play multifunctional roles in ex vivo gene transfer, such as improvement of gene transfer efficacy, separation of cells, and detection of transplanted cells.


BACKGROUND
This study convincingly demonstrates enhanced efficiency of gene transfer via magnetic nanoparticles. The method also enables magnetic sorting of cells positive for the transferred gene, and in vivo monitoring of the process with MRI.
Department of Regenerative Medicine, Kyoto Prefectural University of Medicine, Kyoto, Japan.
Daisuke
D
Kami
Department of Regenerative Medicine, Kyoto Prefectural University of Medicine, Kyoto, Japan.
Tomoya
T
Kitani
Department of Immunology, Kyoto Prefectural University of Medicine, Kyoto, Japan.
Tsunao
T
Kishida
Department of Immunology, Kyoto Prefectural University of Medicine, Kyoto, Japan.
Osam
O
Mazda
Department of Vascular Medicine, Tokyo Metropolitan Institute of Gerontology, Tokyo, Japan.
Masashi
M
Toyoda
Department of Materials Science and Engineering, University of Washington, Seattle, WA, USA.
Asahi
A
Tomitaka
Faculty of Engineering, Yokohama National University, Kanagawa, Japan.
Satoshi
S
Ota
Department of Reproductive Biology and Pathology, National Institute of Child Health and Development, Tokyo, Japan.
Ryuga
R
Ishii
Faculty of Engineering, Yokohama National University, Kanagawa, Japan.
Yasushi
Y
Takemura
Faculty of Engineering, Yokohama National University, Kanagawa, Japan.
Masatoshi
M
Watanabe
Department of Reproductive Biology and Pathology, National Institute of Child Health and Development, Tokyo, Japan.
Akihiro
A
Umezawa
Department of Regenerative Medicine, Kyoto Prefectural University of Medicine, Kyoto, Japan. Electronic address: gojos@koto.kpu-m.ac.jp.
Satoshi
S
Gojo
D000818:Animals; D002469:Cell Separation / Q000379:methods*; D002478:Cells, Cultured; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods*; D058185:Magnetite Nanoparticles / Q000032:analysis / Q000737:chemistry*; D010957:Plasmids / Q000008:administration & dosage*; D011094:Polyethyleneimine / Q000737:chemistry; D014162:Transfection / Q000379:methods*
D058185:Magnetite Nanoparticles; D011094:Polyethyleneimine
Episomal vector; Ex vivo gene transfer; In vitro cell separation; Magnetic nanoparticles; Magnetic resonance imaging