UNS: Collaborative Research: Stem Cell-inspired Nanotherapeutics for Regenerative Repair of Elastic Matrix

PI：Ramamurthi，Anand/Rao，Raj R提案编号：1508642/1509377将结构受损的软、弹性组织恢复到健康状态是困难的，因为成年细胞建立新的弹性纤维的能力很差，这使得组织能够拉伸和回缩。在这个项目中，研究人员建议识别和表征干细胞中对再生和修复弹性纤维组装和结构的影响因素。此外，这些研究的目标是使用可降解的聚合物颗粒以持续的方式传递因子，这些聚合物颗粒本身经过化学修饰，以刺激新的弹性纤维的形成并防止其破裂。然后，研究人员将测试这些颗粒在治疗腹主动脉瘤方面的有效性，腹主动脉瘤是一种以主要弹性血管(主动脉)结构崩溃为特征的疾病。未来，这一平台技术可以扩展到治疗其他需要结构修复的非血管弹性组织类型(如肺组织)。这项建议旨在开发创新的新方法，以实现在原位，仿生的弹性基质再生修复的软组织，弹性组织结构受损的蛋白水解性损伤。所提出的方法试图克服由稳定的成体细胞类型对破裂的弹性基质进行自我再生修复的固有缺陷。研究人员最近发现，骨髓间充质干细胞(BM-MSC)来源的平滑肌细胞(BM-SMCs)，但不是未分化的BM-MSCs，比成年血管SMCs(健康的，患病的)及其分泌的刺激弹性基质再生修复的SMCs(疾病的，基质组装受损的表型)显著更高。由于干细胞的物理输送面临一些挑战，该项目建议设计和测试一种干细胞启发的、但无细胞的再生方法，用于原位细胞外基质再生修复。该方法是基于持续的局部递送BM-SMC分泌体成分，这些成分被认为是从新型聚合物纳米载体获得的促弹性蛋白再生刺激所必需和充分的，这些新型聚合物纳米载体本身具有促弹性和抗蛋白降解特性。通过针对三个特定目标的实验，研究人员将检验以下假设：a)人骨髓间充质干细胞(HBM-MSCs)可以有效地分化为表现出独特的、决定弹性的表型状态的SMC(HbM-SMC)；b)HbM-SMC对腹主动脉瘤SMC的促弹性作用是由其分泌的营养因子(分泌组)介导的；c)HbM-SMC分泌组的关键成分单独或组合是促弹性和抗蛋白降解作用的必要条件和充分条件；以及d)将关键的HBM-SMC分泌组因子(S)与纳米载体整合将增加数量和AMP；ECM破坏的3-D组织空间中再生弹性基质修复的质量。该项目的广泛研究影响是基于其潜力，即一种新的纳米治疗方法可能使再生的弹性基质修复重现SC分泌物的再生效应。通过这个项目，研究人员将a)为几个教育级别的学生开发教育模块，以更好地了解干细胞和组织工程，以及b)为克利夫兰诊所和弗吉尼亚联邦大学的学生提供独特的跨机构协作培训机会。通过在这些机构开展成熟的暑期实习和外展项目，调查人员将开发出有利于高中生、本科生和普通公众的教育模块。该提案由化学、生物工程、环境和运输系统部门的生物医学工程项目和材料研究部门的生物材料项目共同资助。

PI: Ramamurthi, Anand/ Rao, Raj R Proposal Number: 1508642 / 1509377 Restoring structurally damaged soft, elastic tissues to a healthy state is difficult since adult cells are poorly capable of building new elastic fibers, which allow tissues to stretch and recoil. In this project, the investigators propose identification and characterization of factors derived from stem cells towards regenerating and repairing elastic fiber assembly and structure. Further, the studies aim to deliver factors in a sustained manner using degradable polymeric particles which are themselves chemically modified to stimulate new elastic fiber formation and prevent its breakdown. The investigators will then test the effectiveness of the particles in treating abdominal aortic aneurysms, a disorder characterized by breakdown of the structure of the major elastic blood vessel (aorta). In the future, this platform technology can be extended to treat other non-vascular elastic tissue types (e.g., lung tissue) in need of structural repair. This proposal aims to develop innovative, new approaches to enable in situ, biomimetic elastic matrix regenerative repair in soft, elastic tissues structurally compromised by proteolytic injury. The proposed approach seeks to overcome intrinsically-poor auto-regenerative repair of disrupted elastic matrix by stable adult cell types. The investigators have recently shown bone marrow mesenchymal stem cell (BM-MSC)-derived smooth muscle cells (BM-SMCs), but not undifferentiated BM-MSCs, to be significantly more elastogenic than adult vascular SMCs (healthy, diseased), and their secretions to stimulate elastic matrix regenerative repair by SMCs of a diseased, matrix assembly-impaired phenotype. As physical delivery of stem cells faces several challenges, this project proposes to design and test a stem cell-inspired, but cell-free regenerative approach to in situ ECM regenerative repair. The approach is based on sustained, local delivery of BM-SMC secretome components identified to be necessary and sufficient for pro-elastin regenerative stimulus from novel polymer nanocarriers that themselves exhibit pro-elastogenic and anti-proteolytic properties. Through experiments designed to address three specific aims, the investigators will test hypotheses that a) human BM-MSCs (hBM-MSCs) can be efficiently differentiated into SMCs (hBM-SMCs) exhibiting distinct, elastogenicity-determining phenotypic states; b) pro-elastogenic effects of hBM-SMCs on abdominal aortic aneurysm SMCs are mediated by their secreted trophic factors (secretome); c) key components of hBM-SMC secretome individually or in combination are necessary and sufficient for pro-elastogenic and anti-proteolytic effect; and d) integrating sustained delivery of key hBM-SMC secretome factor(s) with nanocarriers will augment quantity & quality of regenerative elastic matrix repair in an ECM-disrupted, 3-D tissue space. The broad research impact of this project is based on its potential that a novel nanotherapeutic approach may enable regenerative elastic matrix repair that recapitulates regenerative effects of SC secretions. Through this project, the investigators will a) develop educational modules for students at several educational levels to better understand stem cell- and tissue engineering, and b) provide unique inter-institutional collaborative training opportunities for students at Cleveland Clinic and Virginia Commonwealth University. By working through well-established summer internship and outreach programs at these institutions, the investigators will develop educational modules that will benefit high school students, undergraduate students and the general public. This proposal is co-funded by the Biomedical Engineering Program in the Chemical, Bioengineering, Environmental and Transport Systems Division, and by the Biomaterials Program in the Division of Materials Research.