Ice Free Vitrification and nanowarming of large cartilage samples for transplantation

临床上采用冷保存的同种异体骨软骨移植物进行关节软骨表面置换， 创伤和骨关节炎引起的关节软骨表面损伤。移植软骨细胞活性 关节软骨被认为是骨软骨移植后结果的决定因素之一 移植我们以前已经开发了一种无冰玻璃化冷冻保存方法， 在动物模型和人关节软骨中保持优异的软骨细胞活力。软骨细胞 由于在1- 3 mL样品的冷却和加热期间没有冰形成，因此能够在玻璃化中存活。 然而，由于复温过程中的冰成核， 导致软骨细胞活力丧失。该提案的创新涉及一种新的复温方法， 不存在边界对流加热的局限性，边界对流加热应对高达50 mL的样品有效 在数量上。这种复温方法利用磁性铁纳米颗粒的射频诱导加热。我们 将优化全层骨软骨储存的预处理， 和细胞外基质的完整性。这一目标将分为两个具体目标， 变量和规模从5 mL到30- 50 mL体积。纳米武装的软骨细胞活力、化学和 将生物材料性能与未处理的新鲜对照组织进行比较。这些条件是 提供了软骨细胞的最佳保存， 选择用于进一步的体内研究，并在随后的II期SBIR中转化为人软骨 应用程序.

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. We have previously developed an ice-free vitrification method of cryopreservation that maintains excellent chondrocyte viability in animal model and human articular cartilage. The chondrocytes survive vitrification due to the absence of ice formation during cooling and warming of 1-3mL samples. However, it has not been possible to rewarm larger samples due to ice nucleation during rewarming that results in loss of chondrocyte viability. The innovation in this proposal relates to a new rewarming method that does not have the limitations of boundary convection warming that should be effective for samples up to 50mL in volume. This rewarming method utilizes radio frequency induced heating of magnetic iron nanoparticles. We will optimize nanowarming of full thickness osteocartilage storage for maintenance of both chondrocyte viability and extracellular matrix integrity. This objective will be developed in two specific aims to optimize nanowarming variables and scaleup from 5mL to 30-50mL volumes. Nanowarmed chondrocyte viability, chemistry, and biomaterial properties will be compared with untreated fresh control tissue. The nanowarming conditions that provides the best preservation of chondrocytes 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.