Department of Reseach Center, Plastic Surgery Hospital, Chinese Academy of Medical Sciences, Peking Union Medical College, 100144 Peking, China.
Anat Rec (Hoboken). 2012 Jul;295(7):1109-16. doi: 10.1002/ar.22500. Epub 2012 May 30.
For the application of bone marrow stromal cells (BMSCs) in cartilage tissue engineering, it is imperative to develop efficient strategies for their chondrogenic differentiation. In this study, the conditioned media derived from chondrocyte/scaffold constructs were used to direct chondrogenic differentiation of BMSCs. The porcine articular chondrocytes were seeded on the PGA/PLA scaffolds to form chondrocyte/scaffold constructs and were cultured to form engineered cartilage in vitro. The culture media were collected as conditioned media and used for chondrogenic induction of BMSC pellets (experimental group, Exp.). The chondrocyte pellets and BMSC pellets were cultured routinely as positive control (PC) and negative control (NC), respectively. After 4 weeks, the wet weight and GAG content in Exp. group and PC group were significantly higher than that in NC group. Histological and immunohistochemical analysis showed that cartilaginous tissue was formed with typical cartilage lacuna structure and positive staining of collagen Type II (Col II) in the peripheral area of the BMSC pellets in Exp. group. Gene expression of Sox9, Col II, and COMP in Exp. group and PC group were significantly higher than that in NC group. The growth factors in the conditioned media derived from human costal chondrocytes-scaffold constructs were tested by protein microassay. The conditioned media contained low levels of TGF-β1,2,3, IGF-1 and high levels of IGF-2, FGF-4, and IGFBP4,6, and so forth. The soluble factors derived from the engineered cartilage can induce chondrogenic differentiation of BMSCs independently. Many cytokines may function in chondrogenesis in a coordinated way.
为了将骨髓基质细胞（BMSCs）应用于软骨组织工程，必须开发有效的方法来诱导其向软骨分化。在本研究中，我们使用软骨细胞/支架构建物的条件培养基来指导 BMSCs 的软骨分化。将猪关节软骨细胞接种到 PGA/PLA 支架上，形成软骨细胞/支架构建物，并在体外培养以形成工程化软骨。收集培养的培养基作为条件培养基，用于诱导 BMSC 球状体（实验组，Exp.）的软骨分化。将软骨细胞球状体和 BMSC 球状体分别作为阳性对照（PC）和阴性对照（NC）进行常规培养。4 周后，Exp.组和 PC 组的湿重和 GAG 含量明显高于 NC 组。组织学和免疫组织化学分析显示，Exp.组 BMSC 球状体的外周区域形成了具有典型软骨陷窝结构的软骨组织，且 Collagen Type II（Col II）染色阳性。Exp.组和 PC 组 Sox9、Col II 和 COMP 的基因表达明显高于 NC 组。通过蛋白质微阵列分析了人肋软骨-支架构建物来源的条件培养基中的生长因子。该条件培养基中含有低水平的 TGF-β1、2、3、IGF-1 和高水平的 IGF-2、FGF-4、IGFBP4、6 等。工程化软骨中分泌的可溶性因子可独立诱导 BMSCs 的软骨分化。许多细胞因子可能以协调的方式发挥作用。
