Modulating the Mechanical and Biological Properties of Hybrid Decellularized Adipose Extracellular Matrix Biomaterials

1403301海斯，丹尼尔来自活跃、健康和相对年轻的受试者的骨组织通常不能用于收获和捐赠。由于潜在的供体仍然仅限于与其相关的疾病的临终患者，获得和获得现成、低成本、容易获得和可获得的能够加速和促进颅面、牙科、矫形和整形/重建外科手术的骨修复的人类组织来源的供体材料仍将是临床医生面临的一个挑战。作为一种替代方案，皮下脂肪组织提供了一个容易获得的人类供体材料来源，因为许多健康的人选择性地寻找整形和重建手术，通过抽脂或腹部成形术移除不需要的组织。虽然皮下脂肪提供了大量的人体供体材料，可能适合于再生医学的许多应用，但由于缺乏合适的机械和生物学特性，目前在骨修复方面的应用受到限制。为了解决这一问题，人们开发了一种脂肪组织脱细胞和化学修饰的方法，以提供具有可调机械性能的具有生物活性的细胞外基质(ECM)。本项目将探索该材料是否适合支持骨组织的生长和修复，无论是在体外还是在小鼠模型中，作为材料交联度和机械硬度的函数。来自脂肪组织的脱细胞ECM已被证明可以加速软组织的再生，但缺乏体内可预测的力学性能和完整性限制了这些类型的材料在骨科重建中的应用。该项目将解决用于肌肉骨骼重建的大量临床可用的同种异体材料的需求。作为一个主要目标，该项目将展示合成-脱细胞脂肪ECM(AdECM)生物可降解支架具有控制机械和生物学特性、调节祖细胞和干细胞命运的潜力。第二个目标是建立活体供体的吸脂物作为修复骨和相关组织的潜在同种异体移植来源。这项研究将为以下方面提供重要的见解：(1)基质/干细胞分化和功能中基质力学的作用；(2)与ECM含量相关的杂化支架的力学特性、结构完整性和生物降解性；(3)利用小鼠脊柱融合模型进行adECM和合成杂交物在骨再生中的临床前应用。在所提出的体系中，碱催化的硫醇-丙烯酸酯Michael加成反应将为杂化合成/adecm水凝胶提供基础。该系统提供了具有广泛的机械性能但几乎相同的化学成分的支架。该项目的具体研究任务是：(1)确定合成/adECM杂化支架的力学性能和相对于adECM含量的完整性。(2)研究脂肪来源的基质/干细胞(ASC)、骨髓来源的MSC(BMSC)或基质血管成分(SVF)在体外培养条件下，复合ADECM支架的组成和力学性能与ASC、BMSC和SVF的去向和行为的关系。(3)单独或与ASC、BMSC或SVF复合，检测复合ADECM修复小鼠脊柱融合模型的成骨特性。

1403301 Hayes, Daniel Bone tissue from active, healthy, and relatively young subjects is not routinely available for harvest and donation. As the pool of potential donors remains limited to patients at end of life with its associated infirmities, access to and availability of off-the-shelf, low cost, readily accessible and procurable human tissue-derived donor materials that can accelerate and promote bone repair for craniofacial, dental, orthopaedic, and plastic/reconstructive surgical procedures will remain a challenge for clinicians. As an alternative subcutaneous adipose tissue provides a readily accessible source of human donor material as many healthy individuals electively seek out plastic and reconstructive surgery to remove unwanted tissue via liposuction or abdominoplasty. While subcutaneous adipose provides a large volume of human donor material, potentially suited to many applications in regenerative medicine, the application to bone repair is currently limited by its lack of suitable mechanical and biological properties. To address this issue a process for adipose tissue decelluralization and chemical modification has been developed to provide a biologically active extra cellular matrix (ECM) with tunable mechanical properties. This project will explore the suitability of this material to support bone tissue growth and repair, both ex-vivo and in a mouse model as a function of the material crosslinking and mechanical stiffness.Acellular ECM from adipose tissue has been demonstrated to accelerate the regeneration of soft tissues but a lack of predictable mechanical properties and integrity in vivo limit the application of these types of material for orthopaedic reconstruction. This project will address the need for a high volume, clinically available allogenic material for use in musculoskeletal reconstruction. As a primary objective the project will demonstrate that hybrid synthetic-acellular adipose ECM (adECM) biodegradable scaffolds have the potential to provide control over mechanical and biological properties modulating progenitor and stem cell fate. A secondary objective is establishing lipoaspirates from living donors as a potential allograft resource for repair of bone and related tissues. This research will provide critical insight into: (1) the role of substrate mechanics in stromal/stem cell differentiation and function; (2) mechanical characteristics, structural integrity and biodegradability of hybrid scaffolds with respect to ECM content; (3) pre-clinical utility of adECM and synthetic hybrids in bone regeneration using a murine spinal fusion model. In the proposed system, a well-described base catalyzed thiol-acrylate Michael addition will provide the basis for the hybrid synthetic/adECM hydrogel. This system provides for scaffolds with a wide range of mechanical properties but nearly identical chemical composition. The detailed research tasks of the project are: (1) determine the mechanical properties and integrity of hybrid synthetic/adECM scaffolds with respect to adECM content. (2) Correlate hybrid adECM scaffold composition and mechanical properties with the fate and behavior of adipose derived stromal/stem cells (ASC), bone marrow derived MSC (BMSC) or stromal vascular fraction (SVF) in vitro. (3) Determine the osteogenic properties of hybrid adECM to repair a murine spinal fusion model in vivo either alone or in combination with ASC, BMSC or SVF.