Decellularized Matrix and Cartilage Regeneration

项目摘要 关节软骨修复仍然是一个挑战，因为缺乏血液供应和伴随 创伤后炎症尽管自体软骨细胞移植（ACT）是一种选择， 细胞来源的限制阻碍了这种方法在临床上的广泛应用。最近，越来越多的 有证据表明，成体干细胞是有前途的细胞来源，特别是来自于 滑膜（SDSC），由于其较高的软骨形成潜力和较低的肥大。一个小的活组织检查 关节镜只能提供有限数量的SDSC用于组织再生，因此体外细胞扩增是 不幸的是，在塑料烧瓶上进行常规扩增会导致细胞衰老和细胞凋亡。 增殖和分化能力。我们最近的报道表明脱细胞细胞外基质 SDSC沉积的dECM可增强扩增干细胞的增殖和软骨形成能力。在 我们的中心假设是，SDSC沉积的dECM可以提供一种上级组织特异性的 基质微环境用于软骨再生中人成年SDSC的最佳复壮， 缺陷修复为了实现这一假设，我们想确定SDSC沉积的dECM是否提供了 与来自脂肪的基质相比，用于人成人SDSC再生的上级基质微环境- 来源的干细胞（ADSC）、尿来源的干细胞（UDSC）或真皮成纤维细胞（DF）（目的1）。我们也 计划通过确定负责以下方面的具体矩阵组成部分，探索潜在的恢复活力机制 软骨形成能力的恢复通过触发关键的整合素受体的激活， 扩展的SDSC（目标2）。最后，转化动物模型将用于评价SDSC/dECM修复 战略（目标3）。我们的目的是确定这种新的细胞扩增系统在提供一种新的细胞扩增系统中的功效。 大量高质量的SDSC用于治疗软骨缺损。这一目标与我们的 长期目标是确定改善骨关节炎患者软骨缺损修复的策略 使用自体干细胞。我们预期的研究结果的主要影响将是重要的，不仅在 推进新一代基于干细胞的软骨工程方法的开发， 再生，但也提供了关于干细胞之间的相互作用的基本新知识， 和基质微环境以及潜在的机制，干细胞再生的基础上， 周围的干细胞基质我们的dECM方法还可以为开发其他 组织再生方法。

Project Summary Articular cartilage repair remains a challenge because of the lack of blood supply and accompanying posttraumatic inflammation. Despite the fact that autologous chondrocyte transplantation (ACT) is an option, cell source limitations retard the broad application of this approach clinically. Recently, there is increasing evidence indicating that adult stem cells are promising cell sources, particularly for stem cells derived from synovium (SDSCs), owing to its higher chondrogenic potential and lower hypertrophy. A small biopsy through arthroscopy can only provide a limited number of SDSCs for tissue regeneration, thus in vitro cell expansion is necessary; unfortunately, conventional expansion on plastic flasks causes cell senescence and loss of proliferation and differentiation capacity. Our recent reports indicated that decellularized extracellular matrix (dECM) deposited by SDSCs could enhance expanded stem cells' proliferation and chondrogenic potential. In this proposal, our central hypothesis is that dECM deposited by SDSCs can provide a superior tissue-specific matrix microenvironment for the optimal rejuvenation of human adult SDSCs in cartilage regeneration and defect repair. To achieve this hypothesis, we want to determine whether dECM deposited by SDSCs provides a superior matrix microenvironment for human adult SDSC rejuvenation compared to matrices from adipose- derived stem cells (ADSCs), urine-derived stem cells (UDSCs), or dermal fibroblasts (DFs) (Aim 1). We also plan to explore potential rejuvenation mechanisms by identifying specific matrix component(s) responsible for the rejuvenation of chondrogenic capacity via triggering the activation of critical integrin receptor(s) in expanded SDSCs (Aim 2). Lastly, a translational animal model will be used to evaluate SDSC/dECM repair strategies (Aim 3). Our objective is to determine the efficacy of this novel cell expansion system in providing a high quantity of high-quality SDSCs for the treatment of cartilage defects. This objective is consistent with our long-term goal which is to identify strategies for improved repair of cartilage defects in osteoarthritic patients using autologous stem cells. The primary impact of our expected findings would be significant not only in advancing the development of new generations of stem cell-based approaches for cartilage engineering and regeneration, but also in providing fundamental new knowledge regarding the interaction between stem cell and matrix microenvironment as well as potential mechanisms underlying stem cell rejuvenation by the surrounding stem cell matrix. Our dECM approach may also provide an excellent model for developing other tissue regeneration approaches.