title: Bone marrow mesenchymal stem cells combined with calcium alginate gel modified by hTGF-β1 for the construction of tissue-engineered cartilage in three-dimensional conditions.
abstract: The aim of this study was to investigate the feasibility of Ad-hTGF-β1-transfected bone marrow mesenchymal stem cells (BMMSCs) combined with calcium alginate gel for the construction of tissue-engineered cartilage under three-dimensional conditions. Rat BMMSCs were divided into three groups: the Ad-hTGF-β1 transfection group, the Ad-EGFP transfection group and the control group. The BMMSCs in the Ad-hTGF-β1 transfection group were continually grown. The compound of cell-calcium alginate gel was cultured in a constant temperature incubator. The morphology of cells was examined, and the proliferation of cells was detected by MTT assay. The results from real-time PCR showed that the average relative ratio of TGF-β1 and transcriptional coactivator with PDZ-binding motif (TAZ) in the Ad-hTGF-β1 group was comparable to that of the control group (P<0.05). Using western blotting and immunohistochemistry, strong expression of collagen II in the Ad-hTGF-β1 group was detected. The results from western blotting showed that the expression of TGF-β1 in the Ad-hTGF-β1 group was significantly increased compared with that of the other two groups. The differentiation of BMMSCs was induced by Ad-hTGF-β1 transfection into chondrocytes. TGF-β1 may promote the differentiation of BMMSCs into chondrocytes by TAZ. BMMSCs transfected by Ad-hTGF-β1 could be induced into chondrocytes. These three-dimensional conditions could preferably mimic cell growth patterns in vivo.
authors.affiliation: Department of Micro-Orthopedics, Zhongnan Hospital, Wuhan University, Wuhan 430071,  P.R. China.
authors.forename: Shaobo
authors.initials: S
authors.lastname: Zhu
authors.forename: Tao
authors.initials: T
authors.lastname: Zhang
authors.forename: Chen
authors.initials: C
authors.lastname: Sun
authors.forename: Aixi
authors.initials: A
authors.lastname: Yu
authors.forename: Baiwen
authors.initials: B
authors.lastname: Qi
authors.forename: Hao
authors.initials: H
authors.lastname: Cheng