Comparative Orthopaedic Laboratory, University of Missouri, Columbia, USA.
Am J Sports Med. 2012 Nov;40(11):2542-8. doi: 10.1177/0363546512458575. Epub 2012 Sep 12.
Osteochondral allografts (OCAs) are currently preserved at 4°C and used within 28 days of donor harvest. The window of opportunity for implantation is limited to 14 days due to a 2-week disease testing protocol.
Osteochondral allograft tissues stored at 37°C will have significantly higher chondrocyte viability, as well as superior biochemical and biomechanical properties, than those stored at 4°C.
Controlled laboratory study.
Osteochondral allografts from 15 adult canine cadavers were aseptically harvested within 4 hours of death. Medial and lateral femoral condyles were stored in Media 1, similar to the current standard, or Media 2, an anti-inflammatory and chondrogenic media containing dexamethasone and transforming growth factor-β3, at 4°C or 37°C for up to 56 days. Chondrocyte viability, glycosaminoglycan (GAG) and collagen (hydroxyproline [HP]) content, biomechanical properties, and collagen II and aggrecan content were assessed at days 28 and 56. Five femoral condyles were stored overnight and assessed the next day to serve as controls.
Storage in Media 1 at 37°C maintained chondrocyte viability at significantly higher levels than in any other media-temperature combination and at levels not significantly different from controls. Osteochondral allografts stored in either media at 4°C showed a significant decrease in chondrocyte viability throughout storage. Glycosaminoglycan and HP content were maintained through 56 days of storage in OCAs in Media 1 at 37°C. There were no significant differences in elastic or dynamic moduli among groups at day 56. Qualitative immunohistochemistry demonstrated the presence of collagen II and aggrecan throughout all layers of cartilage.
Osteochondral allograft viability, matrix content and composition, and biomechanical properties were maintained at "fresh" levels through 56 days of storage in Media 1 at 37°C. Osteochondral allografts stored at 4°C were unable to maintain viability or matrix integrity through 28 days of storage. These findings suggest that storage of OCAs in a defined media at 37°C is superior to current protocols (4°C) for tissue preservation prior to transplantation.
Storage of OCAs in serum-free chemically defined media at 37°C can increase the "window of opportunity" for implantation of optimal tissue from 14 days to 42 days after disease testing clearance.
目前，异体骨软骨移植物（OCAs）在 4°C 下保存，并在供体采集后 28 天内使用。由于有为期两周的疾病检测协议，植入的机会窗口仅限于 14 天。
在 37°C 下储存的异体骨软骨移植物组织的软骨细胞活力将显著更高，并且生化和生物力学特性也将优于在 4°C 下储存的组织。
对照实验室研究。
在死后 4 小时内，从 15 只成年犬尸体中无菌采集骨软骨移植物。内侧和外侧股骨髁分别在 Media 1 中（类似于当前的标准）或 Media 2 中（一种含有地塞米松和转化生长因子-β3 的抗炎和软骨形成介质）储存，在 4°C 或 37°C 下储存长达 56 天。在第 28 天和第 56 天评估软骨细胞活力、糖胺聚糖（GAG）和胶原蛋白（羟脯氨酸[HP]）含量、生物力学特性以及胶原蛋白 II 和聚集蛋白的含量。五个股骨髁储存过夜，第二天进行评估作为对照。
在 Media 1 中 37°C 下储存可保持显著更高水平的软骨细胞活力，高于任何其他介质-温度组合，且与对照组无显著差异。在 4°C 下储存的任何介质中的异体骨软骨移植物均表现出在整个储存过程中软骨细胞活力的显著下降。在 37°C 下储存的 Media 1 中的 OCAs 中，GAG 和 HP 含量可维持 56 天。在第 56 天，各组之间的弹性和动态模量没有显著差异。定性免疫组织化学显示所有软骨层均存在胶原蛋白 II 和聚集蛋白。
在 37°C 的 Media 1 中储存 56 天可保持异体骨软骨移植物的活力、基质含量和组成以及生物力学特性达到“新鲜”水平。在 4°C 下储存的异体骨软骨移植物无法在 28 天的储存期内保持活力或基质完整性。这些发现表明，在移植前，将 OCAs 储存在无血清的化学定义培养基中 37°C 下的储存优于当前的（4°C）组织保存方案。
在无血清的化学定义培养基中 37°C 下储存 OCAs 可将优化组织的“机会窗口”从疾病检测清除后的 14 天增加到 42 天。
