Articular cartilage stem cells

描述(申请人提供)：成人关节软骨被发现实际上含有一小部分具有有限分化潜力的常驻干细胞： 当这些细胞被放置在与MSCs成为软骨内软骨细胞完全相同的条件下时，这些细胞成为永久软骨细胞。是什么使得这些常驻干细胞的分化途径不同于MSCs，以及似乎所有其他已经测试过软骨生成的干细胞？我们假设关节软骨干细胞(ACSCs)的谱系限制是由RNA表达的差异所驱动的。检验这一假说的具体目的是确定关节软骨之间转录的差异。 干细胞和间充质干细胞以及它们分化成的永久软骨细胞和软骨内软骨细胞。下一代RNA测序技术将用于比较ACSCs和MSCs的转录本以及从这两种干细胞类型分化的软骨细胞的转录本。控制ACSCs和MSCs分化的途径将被确定。分析将包括microRNA，我们的目标是确定参与调节这两种干细胞类型的分化潜力以及永久和软骨内软骨细胞分化的那些RNA。目前还没有定义ACSC群体的标记。尽管有几个小组建议细胞表面标志物可以定义ACSCs，但这些还没有得到严格的检验。到目前为止，还没有对标志物进行全面的筛查。我们假设可以像对其他干细胞类型所做的那样为ACSC群体确定标记的组合。表面标记阵列技术将用于搜索可用于定义ACSC种群的标记组合。然后，这些标记可以用于有效地分离永久软骨生成干细胞，用于组织工程，并评估软骨病理不同阶段的干细胞水平。

DESCRIPTION (provided by applicant): Adult articular cartilage has been found to actually contain a small population of resident stem cells that have a restricted differentiation potential: these cells become permanent chondrocytes when placed in exactly the same conditions under which MSCs become endochondral chondrocytes. What makes the differentiation pathway for these resident stem cells different from MSCs, and seemingly all other stem cells for which chondrogenesis has been tested? We hypothesize that the lineage restriction of articular cartilage stem cells (ACSCs) is driven by differences in RNA expression. The specific aim to test this hypothesis is to define the differences in the transcriptomes between articular cartilage stem cells and mesenchymal stem cells and the permanent and endochondral chondrocytes they differentiate into. Next generation RNA sequencing techniques will be used to compare the transcriptomes of ACSCs and MSCs and the transcriptomes of the chondrocytes differentiated from these two stem cell types. Pathways that control the differential differentiation of ACSCs and MSCs will be identified. The analysis will include microRNAs and we aim to identify those involved in the regulation of the differentiation potential of the two stem cell types as well as permanent and endochondral chondrocyte differentiation. There are presently no markers that define the ACSC population. Although several groups have suggested cell surface markers can define ACSCs, these have not been rigorously examined. To-date, no comprehensive screen for markers has been conducted. We hypothesize that a combination of markers can be determined for the ACSC population in the manner done for other stem cell types. Surface marker array technology will be used to search for a combination of markers that can be used to define the ACSC population. Such markers can then be used to efficiently isolate permanent cartilage-producing stem cells for tissue engineering, and assess the level of stem cells in different stages of cartilage pathologies.