Optimization of engineered endplates to improve in vivo integration of atissue engineered intervertebral disc

优化工程终板以改善组织工程椎间盘的体内整合

• 批准号: 10624249
• 负责人: SARAH E GULLBRAND
• 金额: --
• 依托单位: PHILADELPHIA VA MEDICAL CENTER
• 依托单位国家: 美国
• 财政年份: 2019
• 资助国家: 美国
• 起止时间: 2019-12-01 至 2023-09-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10624249
• 关键词: Address; Adult; Aging; Alkaline Phosphatase; Animal Model; Animals; Area; Back Pain; Biological; Biological Assay; Biological Process; Biomechanics; Blood Vessels; Caring; Cartilage; Clinical; Clinical Treatment; Convection; Deposition; Development; Diffusion; Economic Burden; Engineering; Fibrocartilages; General Population; Genes; Geometry; Goals; Growth Factor; Histologic; Histology; Homeostasis; Human; Hyaline Cartilage; Hydrogels; Hydroxyapatites; Image; Implant; In Vitro; Injections; Injury; Intervertebral disc structure; Label; Lesion; Location; Low Back Pain; Magnetic Resonance Imaging; Mechanics; Mesenchymal Stem Cells; Microcapsules drug delivery system; Microfils; Microspheres; Minerals; Modification; Molds; Monitor; Motion; Nutrient; Operative Surgical Procedures; Oryctolagus cuniculus; Osteogenesis; Outcome; Pathology; Patients; Performance; Physiological; Play; Polymers; Procedures; Process; Reaction; Rehabilitation therapy; Research; Role; Sodium Chloride; Speed; Spinal; Structure; Surface; System; Technology; Testing; Thinness; Tissue Engineering; Tissues; Torsion; Translations; Tube; United States; Vascular Endothelial Growth Factors; Vascularization; Vertebral Bone; Vertebral column; Veterans; Weight-Bearing state; Work; active duty; analog; bone; caprolactone; cell growth; chronic pain; contrast enhanced; cortical bone; design; disability; disc regeneration; fluorexon; implantation; improved; in vivo; insight; interfacial; intervertebral disk degeneration; military veteran; mineralization; neovascularization; nucleus pulposus; nutrition; osteogenic; release factor; restoration; scaffold; small molecule; social; spine bone structure; translational goal; treatment strategy; vertebra body

Low back pain, most commonly caused by degeneration of the intervertebral disc, places a significant social and economic burden on the general public, active duty military and veterans alike. Current clinical treatments for disc degeneration are limited in that they do not restore disc structure or function. To address this, our group has developed a whole, tissue engineered intervertebral disc composite (eDAPS) composed of engineered annulus fibrosus, nucleus pulposus and endplate regions. The endplate component, composed of an acellular porous polymer foam, is a critical aspect of the design that forms the interface between the engineered disc and native vertebral bone, but has yet to be optimized to promote the accelerated development of a vascularized, boney interface. The purpose of this study is to generate design modifications to the endplate region of the eDAPS that will accelerate integration following in vivo implantation. We will achieve this translational goal through two Aims: Aim 1: Modify the composition and geometry of the endplate region of the eDAPS to enhance osteogenesis and neovascularization. In this Aim, poly(ε-caprolactone) (PCL) endplates will be fabricated via a salt-leaching procedure with various design modifications to promote osteogenesis and neovascularization. PDMS molds will first be used to create macroscopic channel geometries within the endplates. Endplates will be further modified via hydroxyapatite deposition, and the incorporation of microspheres containing vascular endothelial growth factor (VEGF). The potential for mesenchymal stem cell osteogenesis on the hydroxyapatite modified scaffolds will be established in vitro, via the alkaline phosphatase assay, qPCR analysis of osteogenic genes, and histology. The bioactivity of the VEGF released from the microsphere containing scaffolds will also be assessed in vitro using the tube formation assay. Aim 2: Determine the effect of optimized endplate design on the in vivo integration and nutrition of a whole tissue engineered disc construct. In this Aim, optimized endplates will be utilized in eDAPS to be implanted in vivo in the rabbit lumbar spine for 10 or 20 weeks. New bone and vascular formation in the endplates following in vivo implantation will be assessed via calcein and alizarin labelling and microFil enhanced µCT, respectively. Small molecule trans-endplate diffusion into the engineered disc implants will be assessed via post-contrast enhanced MRI. Integration strength of the eDAPS with the native vertebral bodies will be assessed via tension, compression and torsional mechanical testing at physiologic loads. Animal functional rehabilitation following eDAPS implantation will be assessed via activity monitoring using the Motionwatch-8R, and ground reaction force mapping during ambulation using a Tekscan system. The proposed work will advance the state-of-the art in the field of intervertebral disc tissue-engineering, and provide insights that will speed translation of the eDAPS technology towards clinical use.

腰痛，最常见的是椎间盘变性引起的， 将重要的社会和经济伯恩恩放在公众现役 军人和退伍军人。当前的椎间盘变性临床治疗受到限制 因为它们不会恢复光盘的结构或功能。为了解决这个问题，我们的小组有 开发了整个组织设计的椎间盘复合材料（EDAPS）组成 工程的环形纤维，底核和终板区域端板 由细胞多孔聚合物泡沫组成的成分是 设计的设计形成工程盘和本地椎骨之间的接口， 但尚未优化以促进血管化的加速发展 Boney界面。这项研究的目的是为 EDAPS的端板区域将加速在体内集成之后的集成 植入。我们将通过两个目标实现这一翻译目标：目标1：修改 EDAPS的终板区域的组成和几何形状以增强 成骨和新血管形成。在此目的中，聚（ε-二烯酮）（PCL）终结物 将通过盐浸泡程序制造，并进行各种设计修改 促进成骨和新血管形成。 PDMS模具将首先用于创建 终结物中的宏观通道几何形状。终结将进一步修改 通过羟基磷灰石沉积，并掺入含有血管的微球 内皮生长因子（VEGF）。间充质干细胞成骨的潜力 在氢氧化石上修饰的支架将在体外通过合金建立 磷酸酶测定，成骨基因的QPCR分析和组织学。生物活性 从包含脚手架的微球释放的VEGF也将在 使用管形成测定法。 AIM 2：确定优化端板的效果 整个组织工程盘的体内整合和营养的设计 构造。在此目标中，将在EDAPS中使用优化的终结板将植入 兔腰椎体内10或20周。新骨和血管形成 体内植入后的终结物将通过钙钙蛋白酶和艾他林进行评估 标记和缩影增强了µCT。小分子式式板 扩散到工程圆盘的凹痕将通过后对比增强进行评估 MRI。将评估EDAPS与天然椎体的集成强度 通过张力，压缩和扭转机械测试在生理负荷下。动物 EDAPS植入后的功能康复将通过活动评估 使用MotionWatch-8R进行监视，并在 使用TekScan系统的行走。拟议的工作将推动最先进 在椎间盘组织工程领域 将EDAPS技术转换为临床使用。