Total Joint Resurfacing

全关节表面重修

• 批准号: 8309227
• 负责人: JAMES E DENNIS
• 金额: $ 11.77万
• 依托单位: CASE WESTERN RESERVE UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2011
• 资助国家: 美国
• 起止时间: 2011-08-01 至 2013-07-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8309227
• 关键词: Adhesives; Animals; Area; Arthritis; Autologous; Biomechanics; Bioreactors; Carbodiimides; Cartilage; Cell Culture Techniques; Cells; Chondrocytes; Collagen; Defect; Degenerative polyarthritis; Engineering; Ensure; Failure; Fibrin Tissue Adhesive; Goals; Goat; Growth Factor; Harvest; Histology; Hyaluronan; Image; Immunochemistry; Implant; In Vitro; Joints; Lateral; Length; Life; Magnetic Resonance Imaging; Maps; Measures; Mechanics; Mesenchymal Stem Cells; Methods; Modeling; Nude Mice; Omega-3 Fatty Acids; Operative Surgical Procedures; Organ Culture Techniques; Oryctolagus cuniculus; Outcome; Paste substance; Pre-Clinical Model; Procedures; Production; Property; Prosthesis; Replacement Arthroplasty; Sheep; Site; Surface; Testing; Thick; Tissue Engineering; Tissues; Variant; Wound Healing; adhesive polymer; alternative treatment; articular cartilage; base; bone; calcium phosphate; cartilage repair; density; design; follow-up; implant material; implantation; in vivo; in vivo Model; repaired; scaffold; sound; stem

Total Joint Resurfacing Previous attempts to repair articular cartilage have focused on the repair of focal defects. One of the main complications of focal defect repair is that integration of the repair tissue with the surrounding native cartilage is inconsistent and generally poor, which renders the repair site biomechanically unstable not clinically efficacious. In the case of severe osteoarthritis where the entire joint surface has deteriorated, the procedures for repair of focal cartilage defects are no longer applicable. For severe arthritis, total joint replacement is the final option which, although it has a generally good outcome, there are still long-term complications including, erosion of the articulating surface of the prostheses, and breaking or loosening of the prosthetic stem. These problems necessitate revision surgery which is progressively more difficult and complicated. To obviate this problem, we propose to design and test a tissue engineered cell-matrix composite for the total resurfacing of a joint or joint compartment, which is designed to eliminate cartilage-tocartilage integration problems and provide a cell-based option for totally resurfacing joints without totally replacing them. The primary challenges for tissue engineering the total cartilage resurfacing of a joint are to produce viable cartilage tissue of sufficient thickness and surface area to cover an entire joint, to produce cartilage that has appropriate mechanical properties to support the in vivo mechanical demands, and to ensure the integration of the construct with underlying bone. The goal of this proposal is to produce functional autologous cartilage constructs using tissue engineering principles wherein autologous cells, such as Mesenchymal Stem Cells (MSCs), auricular or articular chondrocytes are used to produce full-thickness replacement cartilage and that is then fused and allowed to integrate onto sub-chondral bone, thus totally replacing the deteriorated cartilage with autologous engineered cartilage. This approach is based on the hypothesis that the production of full-thickness cartilage implants obviates the intractable difficulty of lateral cartilage integration, and functional long-term repair will be accomplished by producing biomechanically sound autologous cartilage. The specific aims of this proposal are: 1. To produce implantation-ready tissue engineered cartilage constructs: In a rabbit model, MSCs and culture-expanded chondrocytes will be used to produce full-thickness (300 um) cartilage constructs of sufficient area to cover an entire humeral condyle. Variables to be tested include the use of auricular or articular chondrocytes or MSCs; hyaluronan- or collagen-based scaffolds; and variations in culture conditions such as cell seeding density, medium flow rate, and the addition of growth factors such as TGF-p1, TGFpS, BMPs, and omega-3 fatty acids. 1. To test implantation-ready constructs in an ex vivo model for cartilage resurfacing: Implant materials synthesized to the proper thickness and surface area will be fixed onto explanted rabbit humeral condyles using four adhesive methods: a calcium phosphate paste, fibrin glue, a final using the zero-length cross-linker1-Ethyl-3-{3-dimethylaminopropyl} carbodiimide, and APTMS-MBA (aminopropyltrimethoxysilanemethylenebisacrylamide), a non-toxic polymer adhesive. These adhesive materials will be tested for their biomechanical properties in vitro, in organ culture, and after implantation into athymic mouse hosts for up to 6 weeks. Biomechanical properties to be tested include a map of surface stiffness, and measures under uniaxial tension and horizontal shear (to failure). MRI imaging, histological examination, and immunochemistry will be used to determine the consistency of cartilage thickness and integration into subchondral bone. 2. To test constructs in an in vivo model of cartilage resurfacing in rabbits: Autologous engineered cartilage constructs will be used to resurface entire humeral condyles in rabbits. The implants will be harvested and examined for biomechanical properties and histology at 4, 12, 24 and 48 weeks post-implantation. Through the use of the Cell, Bioreactor and Imaging Cores, the goals of this proposal will be more easily and efficiently accomplished. The Core components are very appropriate for this project as there is a high demand for cells (chondrocytes and MSCs), bioreactors are need to fabricate cartilage tissue, and imaging is needed for outcome analysis. If these studies are successful, the follow-up study would be to reproduce these results in a large animal pre-clinical model such as in sheep or goats. The long-term objective of this study is to provide an alternative treatment for severe arthritis of diarthrodial joints that is composed of living autologous tissue which, hopefully, will provide many years of functional use before the need for total joint replacement.

全关节表面重修 先前修复关节软骨的尝试主要集中于修复局灶性缺损。中的一个 局灶性缺损修复的主要并发症是修复组织与周围原生组织的整合 软骨不一致且普遍较差，这使得修复部位在生物力学上不稳定 临床有效。如果是严重的骨关​​节炎，整个关节面都恶化了， 局部软骨缺损修复程序不再适用。对于严重关节炎，全关节 更换是最后的选择，虽然总体效果良好，但仍存在长期问题 并发症包括假体关节表面的侵蚀以及假体的断裂或松动 假体柄。这些问题需要进行修复手术，而修复手术变得越来越困难并且 复杂的。为了避免这个问题，我们建议设计并测试组织工程细胞基质 用于关节或关节室的完全表面重修的复合材料，旨在消除软骨间软骨 集成问题，并提供基于细胞的选项，用于完全重修关节，而无需完全 替换它们。 组织工程关节的全软骨表面重修的主要挑战是产生 具有足够厚度和表面积的活软骨组织，以覆盖整个关节，以产生软骨 具有适当的机械性能来支持体内机械需求，并确保 结构与底层骨骼的整合。该提案的目标是产生功能性的 使用组织工程原理构建自体软骨，其中自体细胞，例如 间充质干细胞 (MSC)、耳廓或关节软骨细胞用于产生全层软骨 替换软骨，然后融合并整合到软骨下骨上，从而完全 用自体工程软骨替换恶化的软骨。 该方法基于以下假设：全层软骨植入物的生产 消除了外侧软骨整合的棘手难题，功能性长期修复 通过生产生物力学上健全的自体软骨来实现。 该提案的具体目标是： 1. 生产可植入的组织工程软骨结构：在兔模型中，间充质干细胞 培养扩增的软骨细胞将用于生产全厚度（300 um）软骨结构 足够的面积覆盖整个肱骨髁。要测试的变量包括使用耳廓或 关节软骨细胞或间充质干细胞；基于透明质酸或胶原蛋白的支架；和培养条件的变化 例如细胞接种密度、培养基流速以及生长因子如TGF-p1、TGFpS的添加， BMP 和 omega-3 脂肪酸。 1. 在软骨表面重修的离体模型中测试可植入的结构：植入物 合成适当厚度和表面积的材料将被固定到移植的兔肱骨上 髁突使用四种粘合方法：磷酸钙糊、纤维蛋白胶、最后使用零长度 交联剂1-乙基-3-{3-二甲基氨基丙基}碳二亚胺和APTMS-MBA（氨基丙基三甲氧基硅烷亚甲基双丙烯酰胺）， 一种无毒的聚合物粘合剂。这些粘合材料将接受测试 体外、器官培养以及植入无胸腺小鼠宿主长达长达 6周。要测试的生物力学特性包括表面刚度图和测量值 单轴拉伸和水平剪切（直至失效）。 MRI 成像、组织学检查和 免疫化学将用于确定软骨厚度和整合的一致性 软骨下骨。 2. 在兔子体内软骨表面重建模型中测试构建体：自体 工程软骨结构将用于重塑兔子的整个肱骨髁表面。植入物 将在植入后 4、12、24 和 48 周收获并检查生物力学特性和组织学。 通过使用细胞、生物反应器和成像核心，该提案的目标将更加 轻松高效地完成。核心组件非常适合这个项目，因为有一个 对细胞（软骨细胞和间充质干细胞）的高需求，需要生物反应器来制造软骨组织，以及 结果分析需要成像。 如果这些研究成功，后续研究将在大规模中重现这些结果 动物临床前模型，例如绵羊或山羊。本研究的长期目标是提供 由活体自体组织组成的严重关节关节炎的替代疗法 希望在需要进行全关节置换之前，它能够提供多年的功能使用。