Cartilage storage solution for chondrocyte viability and biomaterial preservation

描述（由申请人提供）：冷保存的同种异体骨软骨移植物用于关节软骨表面修复，用于临床修复创伤和骨关节炎引起的关节软骨表面损伤。移植关节软骨的软骨细胞活力被认为是同种异体骨软骨移植后预后的决定因素之一。在临床使用软骨之前，需要仔细评估用于软骨储存的冷藏储存方法，因为在储存期间组织可能会经历临床上显著的恶化。我们最近研究了软骨细胞在培养基和储存溶液中储存时的活力和基质通透性，发现它们在用于临床程序的时间框架内都会恶化。在冷冷藏条件下最能保持软骨细胞活力的培养基不能保持基质的渗透性，反之亦然，营养不足的溶液可以保持基质的渗透性，但细胞的活力明显降低。这一目标将分为三个具体目标。在这些目标中，将研究两种溶液配方，一种基于细胞内环境设计，另一种基于细胞外环境设计。软骨细胞活力、化学、生物材料特性和基因表达将在猪软骨储存期间进行比较。基因表达研究将确定哪种配方能维持Sox9、聚集蛋白、II型胶原（相对于去分化标志物I型胶原）、软骨寡聚物基质、基质吸收标志物加上蛋白质和肥厚标记基因的正常软骨表达。在接下来的II期SBIR应用中，将选择能够提供最长时间的软骨细胞保存和正常未经处理的软骨细胞表型，且软骨生物材料变化最小的解决方案进行进一步的体内研究，并将其转化为人体软骨。

DESCRIPTION (provided by applicant): Resurfacing of articular cartilage with cold stored osteochondral allografts is employed clinically for repair of trauma and osteoarthritis-induced articular cartilage surface damage. Chondrocyte viability of transplanted articular cartilage is accepted as one of the determinants of outcome following osteochondral allograft transplantation. Refrigerated storage methods used for cartilage storage prior to clinical cartilage utilization need to be carefully evaluated because the tissue may be experiencing clinically significant deterioration during storage. We have recently investigated cartilage cell viability and matrix permeability during storage in culture medium, as well as storage solutions, and found that both deteriorate within the time frames that they are utilized for clinical procedures. Culture medium that preserves chondrocyte viability best under cold refrigerated storage conditions does not preserve matrix permeability and, vice versa, nutritionally deficient solutions that preserve matrix permeability have significantly less cell viability. This objective ill be developed in three specific aims. In these aims two solution formulations, one based on intracellular and the other on extracellular milieu designs will be investigated. Chondrocyte viability, chemistry, biomaterial properties and gene expression will be compared over time during porcine cartilage storage. The gene expression studies will determine which formulation maintains normal untreated cartilage expression of Sox9, aggrecan, collagen type II (versus dedifferentiation marker collagen type I), cartilage oligomeric matrix, a matrix resorption marker plus protein and hypertrophic marker genes. The solution that provides the longest preservation of chondrocytes with a normal untreated chondrocyte phenotype with minimal if any cartilage biomaterial changes will be selected for further investigation in vivo and translation to human cartilage in a subsequent Phase II SBIR application.