Tailoring of cellular mechanical microenvironments to rescue age-related impairments in bone regeneration

定制细胞机械微环境以挽救与年龄相关的骨再生损伤

• 批准号: 10708034
• 负责人: Elise F Morgan
• 金额: $ 73.31万
• 依托单位: BOSTON UNIVERSITY (CHARLES RIVER CAMPUS)
• 依托单位国家: 美国
• 财政年份: 2022
• 资助国家: 美国
• 起止时间: 2022-09-30 至 2027-05-31
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10708034
• 关键词: Address; Age; Aging; Animals; Architecture; Area; Bioreactors; Bone Injury; Bone Matrix; Bone Regeneration; Cell Differentiation process; Cell Proliferation; Cells; Ceramics; Characteristics; Clinical; Clinical Data; Cues; Data; Data Element; Defect; Elements; Fluorescence; Foundations; Gait; Gene Expression; Generations; Heterogeneity; Histology; Immunohistochemistry; Impairment; Implant; In Vitro; Individual; Injury; Knowledge; Laboratory Study; Light; Liquid substance; Marrow; Mechanical Stimulation; Mechanics; Methods; Modeling; Monitor; Mus; Osteoblasts; Osteogenesis; Outcome; Porosity; Printing; Proliferating; Regenerative response; Research Personnel; Risk; Risk Factors; Role; Site; Stimulus; Stromal Cell-Derived Factor 1; Stromal Cells; Techniques; Technology; Testing; Vascularization; Work; age related; aged; analytical tool; bone; bone cell; bone healing; bone repair; bone strength; bone toughness; cell age; cell behavior; design; digital; healing; in vivo; innovation; leptin receptor; manufacture; mechanical load; mechanical signal; mechanical stimulus; microCT; mineralization; novel; osteoblast differentiation; osteogenic; pressure; protein expression; recruit; response; restoration; scaffold; shear stress; skeletal injury; skeletal stem cell; success; tibia; time use; transcriptome sequencing; transcriptomics

Aging impairs both the responsiveness of bone cells to mechanical loading and the success of bone healing following injury. Growing evidence indicates that these two phenomena are related: local mechanical cues present in the cellular microenvironment (“mechanical microenvironment”) regulate numerous aspects of bone healing, including recruitment and osteoblastic differentiation of marrow stromal cells (MSCs). Importantly, studies by multiple groups of investigators have indicated that aged cells remain mechanosensitive, but require higher stimulus magnitudes. Therefore, the focus of this project is on directly manipulating the mechanical microenvironment during bone healing, via customization of the architecture of additively manufactured (AM), osteoinductive, bioceramic scaffolds, in order to identify how the cellular responses to local mechanical cues differ with age. The hypothesis of this work is that tailoring of cellular mechanical microenvironments through advanced AM scaffold design can rescue age-related impairments in bone regeneration. This work builds on preliminary data demonstrating use of an innovative AM method to print mechanically robust ceramic scaffolds of exceptionally tunable architectures with high porosity (>80%) and pore sizes large enough to facilitate vascularization and osteogenesis in vivo. In Aim 1, we will compare the osteogenic responses of young (12-week-old) vs. mature (77-week-old) vs. aged (104-week-old) murine MSCs to the mechanical microenvironment within mechanically loaded scaffolds in vitro. The local mechanical cues present in these scaffolds will be determined using finite element modeling and mechanical testing, and the cellular responses evaluated using a novel combination of techniques including spatial assessment of the progression of osteogenesis at the single-cell level. Aim 2 will leverage these analytical tools as well, and will compare the bone regeneration responses to tailored mechanical microenvironments within scaffolds implanted in young and aged mice. Together, these two aims address an area of high clinical need and will fill critical gaps in knowledge regarding age-related changes in bone mechano- responsiveness during healing. The outcomes of this work will lay the foundation for a new generation of bone repair technologies that can accommodate alterations in cell behavior with aging and harness cell mechano-sensitivity to promote osteogenic differentiation, bone tissue formation, and ultimately, restoration of bone function following injury.

衰老会损害骨细胞对机械负荷的反应性和骨的成功 受伤后愈合。越来越多的证据表明这两种现象是相关的： 细胞微环境（“机械微环境”）中存在的机械线索调节 骨愈合的许多方面，包括骨髓的募集和成骨细胞分化 基质细胞（MSC）。重要的是，多组研究人员的研究表明，老年人 细胞保持机械敏感性，但需要更高的刺激强度。因此，本次重点 该项目是关于在骨愈合过程中直接操纵机械微环境，通过 定制增材制造 (AM)、骨诱导、生物陶瓷的架构 支架，以确定细胞对局部机械信号的反应如何随着年龄的变化而变化。这 这项工作的假设是通过先进的增材制造来定制细胞机械微环境 支架设计可以挽救与年龄相关的骨再生损伤。这项工作建立在 初步数据证明使用创新的增材制造方法来打印机械坚固的陶瓷 具有高孔隙率 (>80%) 且孔径足够大的可调节结构的支架 促进体内血管形成和成骨。在目标 1 中，我们将比较成骨反应 年轻（12 周龄）与成熟（77 周龄）与老年（104 周龄）小鼠 MSC 的比较 体外机械加载支架内的机械微环境。局部机械线索 这些支架中的存在将使用有限元建模和机械测试来确定，并且 使用新颖的技术组合评估细胞反应，包括空间评估 单细胞水平上成骨的进展。目标 2 也将利用这些分析工具， 并将骨再生反应与定制的机械微环境进行比较 支架植入年轻和老年小鼠体内。这两个目标共同解决了一个高临床领域 需要并将填补有关骨力学与年龄相关变化的知识的关键空白 愈合过程中的反应能力。这项工作的成果将为新一代奠定基础 骨修复技术可以适应细胞行为随衰老和利用的变化 细胞机械敏感性促进成骨分化、骨组织形成，并最终， 损伤后骨功能的恢复。