In Situ Hardening Cell-Laden Constructs for Osteochondral Tissue Engineering

用于骨软骨组织工程的原位硬化细胞负载结构

• 批准号: 9326813
• 负责人: ANTONIOS G. MIKOS
• 金额: $ 33.36万
• 依托单位: RICE UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2015
• 资助国家: 美国
• 起止时间: 2015-09-15 至 2020-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9326813
• 关键词: Acrylates; Address; Aldehydes; Amination; Amines; Articulation; Behavior; Bone Regeneration; Cartilage; Cations; Cell Communication; Cell Transplantation; Cell-Matrix Junction; Cells; Characteristics; Chemicals; Chondrocytes; Chondrogenesis; Chondroitin Sulfate A; Chondroitin Sulfates; Coculture Techniques; Coupled; Crosslinker; Custom; Defect; Development; Diamines; Dose; Encapsulated; Engineering; Formulation; Gel; Glycolates; Goals; Hydrogels; In Situ; In Vitro; Injectable; Joints; Kinetics; Laboratories; Lactones; Lysine; Mechanics; Mesenchymal Stem Cells; Minerals; Modeling; Modification; N-isopropylacrylamide; Natural regeneration; Oryctolagus cuniculus; Osteogenesis; Patients; Physical condensation; Population; Property; Signal Pathway; Signal Transduction; Site; Societies; Stem cells; Structure; Swelling; Synovial joint; System; Technology; Time; Tissue Adhesives; Tissue Engineering; Tissues; Transplantation; Vertebral column; Work; acrylic acid; base; bone; butyrolactone; cartilage regeneration; cartilage repair; chemical addition; crosslink; design; dosage; hydrophilicity; implantation; improved; in vivo; innovation; mechanical properties; novel; osteochondral repair; osteochondral tissue; osteogenic; poly-N-isopropylacrylamide; repaired; tissue regeneration; tissue repair

Project Summary/Abstract The ultimate goal of this proposal is to develop an innovative and modular technology for osteochondral tissue repair comprising injectable, thermally responsive, in situ forming, and biodegradable hydrogel constructs capable of sustaining the delivery of encapsulated chondrogenic and osteogenic cell populations in a spatially directed fashion to promote native tissue regeneration. We hypothesize that a cytocompatible hydrogel system consisting of non-shrinking, injectable hydrogels with fully soluble degradation products will be formed through the combination of custom poly(N-isopropylacrylamide)-based thermogelling macromers and lysine-based crosslinking macromers that also contain sites for covalent attachment of chondroitin sulfate (CS) to enhance the integration of resultant constructs. Additionally, we hypothesize that the incorporation of poly(L-lysine) (PLL) within the thermogelling hydrogel will enhance the chondrogenic capacity of co-encapsulated articular chondrocyte and mesenchymal stem cell (AC-MSC) cocultures via the induction of developmentally relevant condensation signals. Finally, we hypothesize that a bilayered construct combining the CS-modified chondrogenic hydrogel layer with an osteogenic hydrogel layer of designer mineralizing capability will be leveraged to promote effective osteochondral tissue repair. Three Specific Aims are proposed to address these hypotheses. First, a lysine-based polyesterurethane macromer comprising a biodegradable poly(DL-lactic-co- glycolic acid) mid-block and chemically crosslinkable diamine functionalities will be developed, covalently modified with CS, combined with the thermogelling macromer and thoroughly assessed to establish structure- property relationships. Second, PLL will be incorporated into the hydrogels and its effects on the chondrogenesis of encapsulated AC-MSC cocultures will be evaluated. Further, the combined effects of PLL presentation, AC-MSC coculture, and CS-modification of hydrogel constructs on cartilage tissue integration will be also evaluated ex vivo. Third, the hydrogels developed in Specific Aim 1 and optimized for chondrogenic potential in Specific Aim 2 will be merged with hydrogel formulations with high mineralizing capability to yield bilayered hydrogel constructs comprising chondrogenic and osteogenic layers for the effective repair of osteochondral defects. The potential synergistic effects of encapsulated cells in the osteogenic and chondrogenic layers with PLL delivery will be evaluated in vitro and in vivo to determine the most effective configuration for osteochondral tissue repair in a well-established rabbit osteochondral defect model. The proposed system will address persisting significant challenges associated with osteochondral defect repair by enabling stable integration of the construct with the surrounding native cartilage tissue through a highly modular two-component design, while promoting the chondrogenic and osteogenic differentiation of respective cell populations delivered to effect both cartilage and bone regeneration, respectively.

项目概要/摘要 该提案的最终目标是开发一种用于骨软骨组织的创新和模块化技术 修复包括可注射、热响应、原位形成和可生物降解的水凝胶结构 能够在空间上维持封装的软骨形成和成骨细胞群的递送 引导时尚促进天然组织再生。我们假设细胞相容性水凝胶系统 由不收缩、可注射的水凝胶组成，具有完全可溶的降解产物，将通过以下方式形成 基于定制聚（N-异丙基丙烯酰胺）的热凝胶大分子单体和基于赖氨酸的组合 交联大分子单体还含有硫酸软骨素 (CS) 共价连接位点，以增强 所得结构的整合。此外，我们假设聚（L-赖氨酸）的掺入 热凝胶水凝胶内的PLL（PLL）将增强共封装关节的软骨形成能力 通过诱导发育相关的软骨细胞和间充质干细胞（AC-MSC）共培养 冷凝信号。最后，我们假设结合 CS 修饰的双层结构 软骨形成水凝胶层与具有设计师矿化能力的成骨水凝胶层将是 用于促进有效的骨软骨组织修复。提出了三个具体目标来解决这些问题 假设。首先，基于赖氨酸的聚酯聚氨酯大分子单体包含可生物降解的聚(DL-乳酸-共- 乙醇酸）中间嵌段和可化学交联的二胺官能团将被开发，共价 用 CS 进行修饰，与热凝胶大分子单体相结合，并进行彻底评估以建立结构- 财产关系。其次，PLL将被纳入水凝胶及其对水凝胶的影响 将评估封装的 AC-MSC 共培养物的软骨形成。此外，PLL的综合效果 演示、AC-MSC 共培养以及水凝胶结构对软骨组织整合的 CS 修饰将 也可以进行离体评估。第三，在特定目标 1 中开发并针对软骨形成进行优化的水凝胶 具体目标 2 中的潜力将与具有高矿化能力的水凝胶配方合并，以产生 包含软骨层和成骨层的双层水凝胶结构，用于有效修复 骨软骨缺陷。封装细胞在成骨和成骨细胞中的潜在协同作用 将在体外和体内评估具有 PLL 递送的软骨形成层，以确定最有效的 在完善的兔骨软骨缺损模型中进行骨软骨组织修复的配置。这 拟议的系统将解决与骨软骨缺损修复相关的持续重大挑战 通过高度的作用使结构与周围的天然软骨组织稳定整合 模块化双组件设计，同时促进各自的软骨形成和成骨分化 递送的细胞群分别影响软骨和骨再生。