Objective: To invest the repair effect of articular cartilage defects by transplantation of PLGA compounded with mesenchymal stem cells modified by hIGF-1 gene.Methods: After the amplification by polymerase chain reaction(PCR) from pcDNA3.1-hIGF-1,the human insulin-like growth factor-1(hIGF-1) fragment was inserted to plasmid pIRES2-EGFP to get recombinated vector pIRES2-EGFP-hIGF-1,which followed by transfection of restructured vectors to mesenchymal stem cells and determination the expression of hIGF-1 gene.The gene-modified MSCs were compounded with PLGA and then cultured in standard condition.Then,the transplantation of graft to the defect positon of articular cartilage was performed.After the transplantation,the specimens was obtained in different time and the repair was inspected.Results: The reconstructed vector contained hIGF-1 and GFP genes was constructed successfully and high efficiency expression of hIGF-1 was detected in target cells.Compared to the control groups,the group of transplantation of graft compounded with MSCs modified hIGF-1 greatly improved the effect of articular cartilage defects.Conclusions: IGF-1 gene is one of the ideal candidate genes for the gene modification of MSCs,the seed cells of cartilage tissue engineering and the gene-modified MSCs can improved effective the repair of articular cartilage defects.

BACKGROUND: Compared to those original viruses systems, adeasy adenovirus, a recombinant adenoviral system widely used in recent years, based on viruses with a deletion of both El and E3, reported by T.C. He in 1998, is an improved one. It simplifies the generation and production of such viruses and expedite the process of generating and testing recombinant adenoviruses using homologous recombination in bacteria rather than in eukaryotic cells. Moreover, it can be conveniently followed with the aid of green fluorescent protein encoded by EGFP gene incorporated into the viral backbone.OBJECTIVE: To construct the recombinant adenovirus and to evaluate them by transfect them to mesenchymal stem cells (MSCs)and detect the expression of target gene hlGF-I at gene and protein levels.DESIGN: Repetitive measurement wail.SETTING: The Institute of Pediatric Research, Chongqing University of Medical Science.METHODS: The study was performed at the Institute of Pediatric Research, Chongqing University of Medical Science from November 2004 to March 2005. After the amplification of truncated hlGF-1 gene from pcDNA3.l-hlGF-I by polymerase chain reaction (PCR), the gene fragment was inserted into the shuttle plasmid pAdtrack-CMV for homologous recombination with backbone plasmid pAdeasy-I in bacteria BJ5183 to get adenovirus.Ad-hlGF-1. The high titer adenovirus supernatant was obtained by repeated transducing of HEK 293 cells by adenovirus harvested after confirmation of the adenovirus structure. As target cells,MSCs were infected with adenovirus earned target gene, hIGF-1, to determine the expression of hlGF-1 gene.MAIN OUTCOME MEASURES: ① The construction of recombinant adenovirus vector;② the expression of target gene hIGF-1 in HEK 293 cells and the proper multiplicity of infection (MOI); ③ hIGF-1 gene expression in MSCs.RESULTS: The adenovirus vector based on adeasy system was constructed successfully and the Ad-hlGF transducing was successfully or efficiently expressed in MSCs cells. The ideal expression of harvested recombinant adenovirus in MSCs was detected by fluorescence microscope, RT-PCR, immunocytochemistry, and Western Blot.CONCLUSION: Adenovirus vector is an effective vector tools for gene expression and wansfection of MSCs. MSCs transduced with Ad-hIGF-1 maybe another option to gene-modified seed cells for articular cartilage tissue engineering.

The purpose of this study is to investigate the effect of superparamagnetic chitosan FGF-2 gelatin microspheres (SPCFGM) on the proliferation and differentiation of mouse mesenchymal stem cells. The superparamagnetic iron oxide chitosan nanoparticles (SPIOCNs) were synthesized by means of chemical co-precipitation, combined with FGF-2. Then The SPCFGM and superparamagnetic chitosan gelatin microspheres (SPCGM) were prepared by means of crosslinking-emulsion. The properties of SPCFGM and SPIONs were measured by laser diffraction particle size analyser and transmisson electron microscopy. The SPCFGM were measured for drug loading capacity, encapsulation efficiency and release pharmaceutical properties in vitro. The C3H10 cells were grouped according to the different ingredients being added to the culture medium: SPCFGM group, SPCGM group and DMEM as control group. Cell apoptosis was analyzed by DAPI staining. The protein expression level of FGF-2 was determined by Western blot. The proliferation activity and cell cycle phase of C3H10 were examined by CCK8 and flow cytometry. The results demonstrated that both of the SPIOCNs and SPCFGM were exhibited structure of spherical crystallization with a diameter of (25 ± 9) nm and (140 ± 12) μm, respectively. There were no apoptosis cells in the three group cells. Both the protein expression level of FGF-2 and cell proliferation activity increased significantly in the SPCFGM group cells (P < 0.05). The SPCFGM is successfully constructed and it can controlled-release FGF-2, remained the biological activity of FGF-2, which can promote proliferation activity of C3H10 cells, and are non-toxic to the cell.
Animals ; Cell Differentiation ; Cell Line ; Cell Proliferation ; Chitosan ; Fibroblast Growth Factor 2 ; pharmacology ; Gelatin ; Magnetite Nanoparticles ; Mesenchymal Stromal Cells ; drug effects ; Mice ; Microspheres ; Plasmids