Osteogenic differentiation of mesenchymal stem cells promoted by overexpression of connective tissue growth factor.
OBJECTIVE
Large segmental bone defect repair remains a clinical and scientific challenge with increasing interest focusing on combining gene transfection with tissue engineering techniques. The aim of this study is to investigate the effect of connective tissue growth factor (CTGF) on the proliferation and osteogenic differentiation of the bone marrow mesenchymal stem cells (MSCs).


METHODS
A CTGF-expressing plasmid (pCTGF) was constructed and transfected into MSCs. Then expressions of bone morphogenesis-related genes, proliferation rate, alkaline phosphatase activity, and mineralization were examined to evaluate the osteogenic potential of the CTGF gene-modified MSCs.


RESULTS
Overexpression of CTGF was confirmed in pCTGF-MSCs. pCTGF transfection significantly enhanced the proliferation rates of pCTGF-MSCs (P<0.05). CTGF induced a 7.5-fold increase in cell migration over control (P<0.05). pCTGF transfection enhanced the expression of bone matrix proteins, such as bone sialoprotein, osteocalcin, and collagen type I in MSCs. The levels of alkaline phosphatase (ALP) activities of pCTGF-MSCs at the 1st and 2nd weeks were 4.0- and 3.0-fold higher than those of MSCs cultured in OS-medium, significantly higher than those of mock-MSCs and normal control MSCs (P<0.05). Overexpression of CTGF in MSCs enhanced the capability to form mineralized nodules.


CONCLUSIONS
Overexpression of CTGF could improve the osteogenic differentiation ability of MSCs, and the CTGF gene-modified MSCs are potential as novel cell resources of bone tissue engineering.
Key Laboratory of Transplant Engineering and Immunology of Ministry of Health, West China Hospital, Sichuan University, Chengdu 610041, China.
Jin-jing
JJ
Wang
Feng
F
Ye
Li-jia
LJ
Cheng
Yu-jun
YJ
Shi
Ji
J
Bao
Huai-qiang
HQ
Sun
Wei
W
Wang
Peng
P
Zhang
Hong
H
Bu
D002454:Cell Differentiation; D002478:Cells, Cultured; D055513:Connective Tissue Growth Factor / Q000235:genetics / Q000378:metabolism*; D024861:Genetic Enhancement / Q000379:methods; D006801:Humans; D059630:Mesenchymal Stem Cells / Q000166:cytology* / Q000502:physiology*; D010006:Osteoblasts / Q000166:cytology* / Q000502:physiology*; D010012:Osteogenesis / Q000502:physiology*; D011401:Promoter Regions, Genetic / Q000235:genetics; D023822:Tissue Engineering / Q000379:methods*; D015854:Up-Regulation / Q000502:physiology
D055513:Connective Tissue Growth Factor