Collagen turnover-stimulated gene delivery to enhance tissue repair

胶原蛋白周转刺激基因传递以增强组织修复

• 批准号: 1605130
• 负责人: Millicent Sullivan
• 金额: $ 42.5万
• 依托单位: University of Delaware
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2016
• 资助国家: 美国
• 起止时间: 2016-09-01 至 2022-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1605130&HistoricalAwards=false
• 关键词: Collagen; turnover; stimulated; gene; delivery

1605130 - SullivanThis project will develop new materials that can ultimately improve the speed and efficacy of healing in chronic wounds and other injured tissues. Many treatment approaches for difficult-to-heal wounds involve the topical application of healing factors such as growth factor (GF) proteins. However, GF proteins are needed at specific concentrations over a well-defined time course, and topical delivery regimens often fail to produce desired delivery profiles leading to incomplete repair. Accordingly, this project will develop and evaluate a fundamentally new gene delivery approach that will enable improved control over GF delivery. To accomplish this effect, the project will produce biomaterials in which gene particles are integrated into the fibers of collagen gels that are designed to degrade and release GFs at the right time at the local tissue healing site. Completion of the project will result in the acquisition of new scientific understanding at the interface of tissue repair biology and biomaterials engineering by illuminating the ways in which cellular repair mechanisms may be altered when cells encounter engineered materials that mimic native tissues. Ultimately, these material platforms can be applicable in multiple tissue engineering applications such as wound repair and implant functionalization. The efforts will also have broad impacts on bioengineering education and career development of underrepresented students, through new research, classroom, and career development opportunities to graduate students, undergraduates, and high school students. These activities will be facilitated through integration and leadership from the PIs in a variety of on-campus training and mentoring programs.Aberrant extracellular matrix (ECM) synthesis and turnover processes define the success or failure of healing in a wide variety of regenerative medicine applications. Accordingly, improved strategies to understand and manipulate ECM-driven cell growth and growth factor signaling would have enormous benefits in multiple tissue repair technologies. The investigators are developing an innovative approach to improve control over the dynamics and location of growth factor delivery by harnessing ECM remodeling to stimulate growth factor gene release and expression. In particular, investigators will exploit their expertise in designing collagen-mimetic peptide (CMP) nanostructures to engineer DNA polyplex-modified collagen scaffolds that induce localized, high efficiency GF expression coordinated with tissue repair kinetics. The development of CMP-linked gene delivery technologies has transformative potential through its ability to both harness as well as enrich and orchestrate the highly dynamic cellular repair cascades underlying healing. Furthermore, the studies provide unique opportunities to ask fundamental questions at the interface of regenerative biology and biomaterials engineering: (1) Does CMP-mediated integration of gene nanostructures within collagen scaffolds permit gene retention over time periods commensurate with the stability vs. turnover of the scaffold? Are native endocytic collagen processing pathways altered when nanostructures are integrated via triple-helical interactions with CMPs? and (2) Does integration of gene nanostructures within collagen enhance the stability of the genes in a manner akin to ECM-based stabilization of protein factors and viruses? These questions are addressed through two objectives aimed at (1) optimizing the localization and activity of CMP/polyplex-linked collagens for sequestration and delivery of active gene constructs over prolonged time periods, using both in vitro and in vivo repair models to express model genes; and (2) elucidating key design parameters controlling polyplex retention, CMP/polyplex/collagen processing, and improved activity of expressed growth factors such as PDGF. These approaches will ultimately be useful as a versatile biomaterials platform able to stimulate improved healing in a variety of regenerative medicine applications. The project will advance the use of collagen-mediated gene delivery in multiple tissue engineering applications such as wound repair and implant functionalization. The research activities will also serve as a catalyst to provide new research, classroom, and career development opportunities to graduate students, undergraduates, and high school students, particularly through integration and leadership from the investigators in a variety of on-campus training and mentoring programs.

1605130-Sullivan该项目将开发新材料，最终提高慢性伤口和其他受伤组织的愈合速度和效率。许多难以愈合的伤口的治疗方法包括局部应用愈合因子，如生长因子(GF)蛋白质。然而，在一个明确的时间过程中，需要特定浓度的GF蛋白，而局部给药方案往往无法产生所需的给药曲线，导致修复不完全。因此，该项目将开发和评估一种全新的基因传递方法，该方法将使对GF传递的控制得到改善。为了实现这一效果，该项目将生产生物材料，其中基因颗粒被整合到胶原胶原凝胶的纤维中，旨在适当的时间在局部组织愈合部位降解和释放GFS。该项目的完成将通过阐明细胞遇到模仿天然组织的工程材料时细胞修复机制可能发生变化的方式，在组织修复生物学和生物材料工程的界面上获得新的科学理解。最终，这些材料平台可以应用于多种组织工程应用，如伤口修复和植入功能化。这些努力还将通过为研究生、本科生和高中生提供新的研究、课堂和职业发展机会，对生物工程教育和未被充分代表的学生的职业发展产生广泛影响。这些活动将通过PI在各种校园培训和指导计划中的整合和领导来促进。在各种再生医学应用中，细胞外基质(ECM)的合成和周转过程决定着愈合的成败。因此，改进理解和操纵ECM驱动的细胞生长和生长因子信号的策略将在多种组织修复技术中产生巨大的好处。研究人员正在开发一种创新的方法，通过利用ECM重塑来刺激生长因子基因的释放和表达，来改善对生长因子传递的动态和位置的控制。特别是，研究人员将利用他们在设计胶原模拟多肽(CMP)纳米结构方面的专业知识来设计DNA多链修饰的胶原支架，以诱导局部、高效的GF表达，并与组织修复动力学相协调。CMP相关基因传递技术的发展具有变革性的潜力，因为它既能够利用，也能够丰富和协调在愈合基础上的高度动态的细胞修复级联。此外，这些研究提供了在再生生物学和生物材料工程的界面上提出基本问题的独特机会：(1)在胶原支架中，由CMP介导的基因纳米结构整合是否允许基因在与支架的稳定性和周转性相称的一段时间内保留？当纳米结构通过与CMPS的三螺旋相互作用整合时，天然的内细胞性胶原加工途径是否发生了变化？以及(2)基因纳米结构在胶原中的整合是否以一种类似于基于ECM的蛋白质因子和病毒稳定的方式增强了基因的稳定性？这些问题通过两个目标来解决，旨在(1)通过使用体外和体内修复模型来表达模型基因，优化CMP/Polyplex连接的胶原蛋白的定位和活性，以在较长的时间内隔离和传递活性基因构建体；(2)阐明控制Polyplex保留、CMP/Polyplex/胶原蛋白加工和提高表达的生长因子(如PDGF)活性的关键设计参数。这些方法最终将是有用的，作为一个多功能的生物材料平台，能够在各种再生医学应用中刺激改善愈合。该项目将推进胶原介导的基因传递在多种组织工程应用中的使用，如伤口修复和植入功能化。研究活动还将成为催化剂，为研究生、本科生和高中生提供新的研究、课堂和职业发展机会，特别是通过调查人员在各种校园培训和指导计划中的整合和领导。