Influence of transforming growth factor-β2 on differentiation of mesenchymal stem cells into osteoblasts

Objective To investigate the ability of transforming growth factor (TGF)-β2 to differentiate the bone marrow mesenchymal stem cells (BMSCs) into bone cells in vitro.Methods BMSCs of 3rd generation were seeded in 3.5 × 103/pore density culture plate and divided into three groups:A,B and C.Group A received no treatment.Groups B and C received the culture medium containing 5 μg/L TGF-β1 and 5 μg/L TGF-β2 respectively,200 μL per well of each of the four holes.On 7th day,alkaline phosphatase (ALP) activity assay and Western blotting method were applied to detect the expression of collagen Ⅰ.BMSCs of 3rd generation were seeded in six well plates at a density of 5 × 107/L,grouping and treatment principle were performed as described before,and the calcium salts were observed by Von Kassa at the 21st day.Results The ALP activity values in groups A,B and C on 7th day were 1.15 ± 0.16,4.26 ± 0.39 and 4.34 ± 0.14 respectively (P ＜ 0.05).The stained area and depth of ALP and Von kossa staining for calcified nodules were increased in group C as compared with groups A and B,and those in group B were increased as compared with group A.Collagen Ⅰ expression in group C was highest among the groups and lowest in group A.Conclusion Under above mentioned conditions,TGF-β2 induced BMSCs osteogenic capacity significantly stronger than TGF-β1 and the control. Key words: Transforming growth factor-β2;  Transforming growth factor-β1 ;  Bone marrow mesenchymal stem cells;  Osteoblast