Encapsulation of plasmid DNA in calcium phosphate nanoparticles: stem cell uptake and gene transfer efficiency.
BACKGROUND
The purpose of this study was to develop calcium phosphate nanocomposite particles encapsulating plasmid DNA (CP-pDNA) nanoparticles as a nonviral vector for gene delivery.


METHODS
CP-pDNA nanoparticles employing plasmid transforming growth factor beta 1 (TGF-β1) were prepared and characterized. The transfection efficiency and cell viability of the CP-pDNA nanoparticles were evaluated in mesenchymal stem cells, which were identified by immunofluorescence staining. Cytotoxicity of plasmid TGF-β1 and calcium phosphate to mesenchymal stem cells were evaluated by MTT assay.


RESULTS
The integrity of TGF-β1 encapsulated in the CP-pDNA nanoparticles was maintained. The well dispersed CP-pDNA nanoparticles exhibited an ultralow particle size (20-50 nm) and significantly lower cytotoxicity than Lipofectamine™ 2000. Immunofluorescence staining revealed that the cultured cells in this study were probably mesenchymal stem cells. The cellular uptake and transfection efficiency of the CP-pDNA nanoparticles into the mesenchymal stem cells were higher than that of needle-like calcium phosphate nanoparticles and a standard calcium phosphate transfection kit. Furthermore, live cell imaging and confocal laser microscopy vividly showed the transportation process of the CP-pDNA nanoparticles in mesenchymal stem cells. The results of a cytotoxicity assay found that both plasmid TGF-β1 and calcium phosphate were not toxic to mesenchymal stem cells.


CONCLUSIONS
CP-pDNA nanoparticles can be developed into an effective alternative as a nonviral gene delivery system that is highly efficient and has low cytotoxicity.
Department of Pharmaceutics, School of Pharmacy, and Center for Nano Drug/Gene Delivery and Tissue Engineering, Jiangsu University, Jingkou District, Zhenjiang, People's Republic of China.
Xia
X
Cao
Wenwen
W
Deng
Yuan
Y
Wei
Weiyan
W
Su
Yan
Y
Yang
Yawei
Y
Wei
Jiangnan
J
Yu
Ximing
X
Xu
D002130:Calcium Phosphates / Q000737:chemistry*; D018014:Gene Transfer Techniques; D006801:Humans; D059630:Mesenchymal Stem Cells / Q000166:cytology / Q000502:physiology; D053769:Nanocapsules / Q000008:administration & dosage* / Q000737:chemistry* / Q000648:ultrastructure; D010316:Particle Size; D010957:Plasmids / Q000008:administration & dosage* / Q000737:chemistry; D013234:Stem Cells / Q000166:cytology / Q000502:physiology*; D014162:Transfection / Q000379:methods*
D002130:Calcium Phosphates; D053769:Nanocapsules; C020243:calcium phosphate