Laboratory of Molecular Biology of Cartilage, Division of Rheumatology, Department of Clinical Medicine, State University of Campinas.
Clinics (Sao Paulo). 2011;66(3):487-92. doi: 10.1590/s1807-59322011000300022.
Numerous experimental efforts have been undertaken to induce the healing of lesions within articular cartilage by re-establishing competent repair tissue. Adult mesenchymal stem cells have attracted attention as a source of cells for cartilage tissue engineering. The purpose of this study was to investigate chondrogenesis employing periosteal mesenchymal cells.
Periosteum was harvested from patients who underwent orthopedic surgeries. Mesenchymal stem cells were characterized through flow cytometry using specific antibodies. The stem cells were divided into four groups. Two groups were stimulated with transforming growth factor β3 (TGF-β3), of which one group was cultivated in a monolayer culture and the other was cultured in a micromass culture. The remaining two groups were cultivated in monolayer or micromass cultures in the absence of TGF-β3. Cell differentiation was verified through quantitative reverse transcription-polymerase chain reaction (RT-PCR) and using western blot analysis.
In the groups cultured without TGF-β3, only the cells maintained in the micromass culture expressed type II collagen. Both the monolayer and the micromass groups that were stimulated with TGF-β3 expressed type II collagen, which was observed in both quantitative RT-PCR and western blot analysis. The expression of type II collagen was significantly greater in the micromass system than in the monolayer system.
The results of this study demonstrate that the interactions between the cells in the micromass culture system can regulate the proliferation and differentiation of periosteal mesenchymal cells during chondrogenesis and that this effect is enhanced by TGF-β3.
为了通过重新建立有能力的修复组织来诱导关节软骨内病变的愈合，已经进行了许多实验研究。成体间充质干细胞作为软骨组织工程细胞的来源引起了人们的关注。本研究旨在通过研究骨膜间充质细胞来研究软骨生成。
从接受骨科手术的患者中采集骨膜。通过使用特异性抗体的流式细胞术对间充质干细胞进行特征描述。将干细胞分为四组。两组用转化生长因子β3（TGF-β3）刺激，其中一组在单层培养中培养，另一组在微团培养中培养。其余两组在无 TGF-β3 的情况下在单层或微团培养中培养。通过定量逆转录聚合酶链反应（RT-PCR）和 Western blot 分析来验证细胞分化。
在未添加 TGF-β3 的培养组中，只有在微团培养中维持的细胞表达 II 型胶原。用 TGF-β3 刺激的单层和微团培养组均表达 II 型胶原，这在定量 RT-PCR 和 Western blot 分析中均观察到。在微团系统中，II 型胶原的表达明显高于单层系统。
本研究结果表明，微团培养系统中细胞之间的相互作用可以调节骨膜间充质细胞在软骨生成过程中的增殖和分化，并且 TGF-β3 增强了这种作用。
