Osteoblast differentiation in vitro and in vivo promoted by Osterix.

C3H10T1/2/Osx, a stably transfected cell line with Osterix (Osx), was produced and chondrocytic and osteoblastic differentiation were studied in vitro. Osx promoted osteoblastic lineage that was dexamethasone dependent. Furthermore, in vivo, Osx induced ectopic mineralization in a heterotopic mouse muscle model.

A calcium phosphate-based gene delivery system.

Although nonviral vectors have lower transfection efficiency than viral vectors, the excellent safety profile of nonviral vectors is appealing for gene therapy. An efficient, simple nonviral vector gene delivery system has been designed that includes plasmid DNA-calcium phosphate precipitates (pDNA-CaP) and porous collagen spheres (Cultispherestrade mark). The hypothesis for this study was the pDNA-CaP would achieve efficient plasmid DNA transfection and the porous collagen spheres would provide a suitable delivery carrier system for three-dimensional (3D) administration.