title: Coprecipitation of DNA-lipid complexes with apatite and comparison with superficial adsorption for gene transfer applications.
abstract: Apatite can mediate gene transfer into cells by serving as a safe and biocompatible immobilization matrix for DNA and transfection reagents. Recently, an apatite layer that immobilized DNA-lipid complexes was prepared by a coprecipitation process in a supersaturated calcium phosphate solution. This composite layer (DNA-lipid-apatite layer) showed a higher gene transfer capability than an apatite layer with superficially adsorbed DNA-lipid complexes (DNA-lipid-adsorbed apatite layer). In this study, the DNA-lipid-apatite layer and the DNA-lipid-adsorbed apatite layer were compared for their physicochemical properties and gene transfer capabilities. The higher gene transfer capability of the DNA-lipid-apatite layer compared with that of the DNA-lipid-adsorbed apatite layer was reconfirmed by a luciferase assay using epithelial-like CHO-K1 cells. Physicochemical structure analyses showed that the DNA-lipid-apatite layer possessed a larger capacity for DNA-lipid complexes than the DNA-lipid-adsorbed apatite layer. The DNA-lipid-apatite layer released DNA-lipid complexes in a slow and sustained manner, whereas the DNA-lipid-adsorbed apatite layer released them in short bursts. Consequently, the release of DNA-lipid complexes from the DNA-lipid-apatite layer was larger in amount and longer in duration than release from the DNA-lipid-adsorbed apatite layer. This difference in release profiles may be responsible for the higher gene transfer capability of the DNA-lipid-apatite layer compared with that of the DNA-lipid-adsorbed apatite layer. The coprecipitation process and the resulting DNA-lipid-apatite layer have many applications in tissue engineering.
authors.affiliation: 1Research Institute for Science and Engineering, Waseda University, Shinjuku, Tokyo, Japan.
authors.forename: Yushin
authors.initials: Y
authors.lastname: Yazaki
authors.forename: Ayako
authors.initials: A
authors.lastname: Oyane
authors.forename: Hideo
authors.initials: H
authors.lastname: Tsurushima
authors.forename: Hiroko
authors.initials: H
authors.lastname: Araki
authors.forename: Yu
authors.initials: Y
authors.lastname: Sogo
authors.forename: Atsuo
authors.initials: A
authors.lastname: Ito
authors.forename: Atsushi
authors.initials: A
authors.lastname: Yamazaki
mesh_terms: D000327:Adsorption; D000818:Animals; D001031:Apatites / Q000737:chemistry*; D016466:CHO Cells; D006224:Cricetinae; D003412:Cricetulus; D004247:DNA / Q000737:chemistry*; D018014:Gene Transfer Techniques; D008055:Lipids / Q000737:chemistry*; D008855:Microscopy, Electron, Scanning; D014961:X-Ray Diffraction
chemical_list: D001031:Apatites; D008055:Lipids; D004247:DNA
keywords: DNA; Lipid; apatite; composite; gene transfer