Total Joint Resurfacing

全关节表面重修

• 批准号: 8118205
• 负责人: JAMES E DENNIS
• 金额: $ 12.27万
• 依托单位: CASE WESTERN RESERVE UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2010
• 资助国家: 美国
• 起止时间: 2010-08-01 至 2013-07-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8118205
• 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; Follow-Up Studies; 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; 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; density; design; 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where the entire joint surface has deteriorated, the procedures for repair of focal cartilage defects are no longer applicable.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.

总接缝重铺 以往修复关节软骨的尝试主要集中在局部缺陷的修复上。其中一个 局灶性缺损修复的主要并发症是修复组织与周围天然组织的结合。 软骨不一致，通常很差，这使得修复部位的生物力学不稳定 临床疗效显著。如果是严重的骨关节炎，整个关节表面已经恶化， 修复局灶性软骨缺损的程序不再适用。对于严重的关节炎，全关节 替代是最后的选择，虽然总体上结果不错，但仍有长期的 并发症包括假体关节表面的侵蚀，以及假体的断裂或松动 假肢的柄。这些问题需要进行翻修手术，而翻修手术越来越困难，而且 很复杂。为了避免这个问题，我们建议设计和测试一种组织工程细胞基质。 用于关节或关节间隙的整体表面处理的复合材料，其设计目的是消除软骨到软骨 集成问题，并提供基于单元的选项，用于完全重新铺设接头，而无需完全 取而代之。 组织工程学的主要挑战关节的全软骨表面重建是制造 有活力的软骨组织，具有足够的厚度和表面积来覆盖整个关节，以产生软骨 具有适当的机械性能以支持体内的机械需求，并确保 构建物与下层骨的整合。这项提案的目标是生产功能齐全的 利用组织工程学原理构建自体软骨，其中自体细胞，如 间充质干细胞(MSCs)、耳廓或关节软骨细胞用于产生全层软骨细胞 替换软骨，然后融合，并允许整合到软骨下骨，因此完全 用自体工程化软骨替代退化的软骨。 这种方法是基于这样一个假设，即全厚度软骨植入物的生产 避免了外侧软骨整合的难题，功能性的长期修复将是 通过生产生物力学性能良好的自体软骨来完成。 这项建议的具体目标是： 1.构建可植入的组织工程化软骨：在兔模型中，MSCs 培养扩增的软骨细胞将用于生产全厚度(300微米)的软骨结构 有足够的面积覆盖整个肱骨髁部。要测试的变量包括使用耳穴或 关节软骨细胞或间充质干细胞；透明质酸或胶原基支架；以及培养条件的变化 如细胞接种密度、培养基流量以及添加生长因子如转化生长因子β1、转化生长因子β1、 BMPS和omega-3脂肪酸。 1.在软骨表面重建的体外模型中测试可植入的结构：植入物 将合成到适当厚度和表面积的材料固定在移植的兔肱骨上 髁状突采用四种粘接方法：一种是磷酸钙糊，一种是纤维蛋白胶，最后一种是零长粘合剂 交联剂1-乙基-3-{3-二甲氨基丙基]碳二亚胺和APTMS-MBA(aminopropyltrimethoxysilanemethylenebisacrylamide)， 一种无毒的聚合物粘合剂。这些粘合材料将进行测试，以确定其 在体外、器官培养和植入无菌小鼠宿主后的生物力学特性 6周。待测试的生物力学特性包括表面硬度图，以及 单轴拉伸和水平剪切(到破坏)。核磁共振成像，组织学检查，以及 将使用免疫化学方法来确定软骨厚度的一致性和与 软骨下骨。 2.在兔体内软骨表面重建模型中测试构建物：自体 工程化的软骨结构将被用来在兔的整个肱骨髁部表面进行重建。植入物 分别于植入后4周、12周、24周和48周取材，进行生物力学和组织学检查。 通过使用细胞、生物反应器和成像核心，这项提议的目标将更多 轻松高效地完成任务。核心组件非常适合此项目，因为有一个 对细胞(软骨细胞和间充质干细胞)的要求很高，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，后续研究将大量复制这些结果 动物临床前模型，如绵羊或山羊。这项研究的长期目标是提供一个 活体自体组织构成的重症腹泻性关节炎的替代疗法 它有望在需要完全关节置换之前提供多年的功能使用。