Molecular mechanism of the interaction between signals generated by BMP and mechanical stress in osteoblasts

骨和软骨是人体的支撑器官，同时它们也对物理刺激作出反应以维持骨骼组织。本研究旨在对机械应力在骨骼细胞功能调控中的作用进行分类，因此，从携带SV-40大t抗原基因的转基因小鼠中获得了来自承重组织——关节软骨的克隆细胞系。这种大的t抗原在33有活性，在37无活性。为了建立软骨细胞系，我们在低FBS浓度（0.5%）的条件下培养细胞。建立的TC-6细胞聚集体阿利新蓝和甲苯胺蓝染色阳性，表明软骨基质的产生。TC-6细胞也表达II型胶原蛋白、聚集蛋白和连接蛋白基因。外部压力通过细胞附着机制影响细胞。研究了TC-6细胞与细菌培养皿的附着情况，发现TC-6细胞能在培养皿中存活。因此，即使在非附着环境下，这些细胞也能高效地建立附着，这对于研究机械应力和通过附着机制进行的信号转导以及BMP等生长因子的作用是有用的。

Bone and cartilage are supporting organs of the body while they also respond to physical stimuli to maintain the skeletal tissues. This research aimed to classify the roles of mechanical stress in the regulation of skeletal cell function and, therefore, generated a clonel cell line derived from such weight bearing tissue, articular cartilage, from transgenic mice harboring SV-40 large-T antigen gene. This large T-antigen is active at 33ﾟ and inactive at 37ﾟ. To establish chondrocyte cell lines, we cultured the cells at 33ﾟ at a low FBS concentration (0.5%). The established TC-6 cell aggregates were stained positive for alcian blue and toluidine blue, indicating production of cartilage matrix. TC-6 cells also express type II collagen, aggrecan and link protein genes. Extermal stress affects cells via cell attachment machinery. TC-6 cells attachment to bacteriological dish was examined and we found that TC-6 cells can survive in these dish. Therefore, these cells are highly able to establish attachment efficiently even in non-attaching environment and are useful to study mechanical stress and signal transduction via attachment machinery as well as growth factor effects such as those of BMP.