BRIGE: Peptide-Based Cues for Mesenchymal Stem Cell Differentiation in Cartilage Graft Applications

0927100 Liu该奖项是根据2009年美国复苏和再投资法案（公法111-5）资助的。“设计具有诱导或增强成人干细胞分化为软骨细胞的线索的材料将改善骨关节炎患者的治疗选择，骨关节炎是一种影响关节软骨的退行性疾病。健康的软骨可以保护承重骨，并作为关节表面运动的润滑剂，但一旦受损，软骨的再生潜力有限。人们越来越关注利用成体干细胞接种在支架上来开发组织工程软骨替代物。这些细胞通常使用可溶性生长因子和化合物在体外分化。这种方法的一些缺点包括细胞培养时间长，使用超生理浓度的生长因子，以及难以维持关节软骨表型和防止软骨肥大。开发的材料，将有针对性的细胞分化的线索，可以规避这些问题，并有额外的好处，促进设计和建设的一个复杂的三维tissue.Intellectual MeritThe拟议的工作将调查肽序列，来自软骨生长因子，并已被证明在其他生物系统中引起的活动。本工作的目的是1）评估可溶性肽诱导或促进间充质干细胞分化为软骨细胞的能力，2）使用实验设计技术研究协同效应和软骨表型的维持，以及3）开发新型基于蛋白质的支架并在三维支架的背景下证明这些肽的活性。该提案的结果将证明原理，并作为未来NSF提案的初步数据，该提案通过在不同支架的背景下系统地检查肽，将其确立为一般设计规则。未来的提案还将探讨生物化学和生物力学特性在控制细胞分化中的相互作用。此外，这里提出的工作将证明一种新的基于节枝弹性蛋白的蛋白质支架含有化学和光交联位点的实用性。这些结果将作为初步数据的一个单独的建议，调查的生物相容性，机械性能，并在体内使用的软骨工程应用。更广泛的影响拟议的工作将改善技术，治疗软骨损伤的疾病或损伤。此外，这里开发的方法可以扩展用于其他应用，如骨或软组织移植物，并用于设计多细胞组织，如肝脏或血管化器官。PI致力于招聘和保留工程中代表性不足的群体，并将参与对女学生（高中，本科和研究生）的个人和团体辅导。作为妇女在工程项目的一部分，她积极参与研究生导师计划，并正在开发一个实验室模块，向高中生介绍用于评估组织工程支架的高通量技术。来自代表性不足群体的本科生将通过印第安纳州路易斯·斯托克斯少数民族参与联盟（LSAMP）招募，参加夏季和学年的研究。 这项工作还将培训一名女研究生，并通过获得教师职位的过程指导她，她将成为未来学生的榜样和导师。 这项研究将被纳入组织工程和蛋白质工程的本科生和研究生课程的发展。这些课程将强调批判性分析，并通过使用主要文献论文向学生介绍尖端技术。

0927100LiuThis award is funded under the American Recovery and Reinvestment Act of 2009 (Public Law 111-5)."Designing materials with cues to induce or enhance adult stem cell differentiation into cartilage cells would improve treatment options for patients suffering from osteoarthritis, a degenerative disease that affects articular cartilage. Healthy cartilage protects load-bearing bones and serves as a lubricant for moving joint surfaces but once damaged, cartilage has a limited regenerative potential. There is increasing interest in developing tissue engineered cartilage replacements using adult stem cells seeded on a scaffold. These cells are often differentiated in vitro using soluble growth factors and chemical compounds. Some of the drawbacks of this method include the extensive cell culture time, the use of super-physiological concentrations of growth factors, and the difficulty in maintaining the articular cartilage phenotype and preventing cartilage hypertrophy. Development of materials that incorporate cues for targeted cell differentiation could circumvent these issues and have the added benefit of facilitating the design and construction of a complex three-dimensional tissue.Intellectual MeritThe proposed work will investigate peptide sequences that are derived from chondrogenic growth factors and have been shown to elicit activity in other biological systems. The objectives of this work are to 1) evaluate soluble peptides for their ability to induce or promote mesenchymal stem cell differentiation into cartilage cells, 2) investigate synergistic effects and maintenance of the cartilage phenotype using experimental design techniques, and 3) develop a novel protein-based scaffold and demonstrate the activity of these peptides within the context of a three-dimensional scaffold. The results from this proposal will demonstrate proof of principle and serve as preliminary data for a future NSF proposal that establishes the peptides as a general design rule by systematically examining them in the context of different scaffolds. The future proposal will also explore the interactions of biochemical and biomechanical properties in controlling cell differentiation. In addition, the work proposed here will demonstrate the utility of a new resilin-based protein scaffold containing chemical and photocrosslinking sites. These results will serve as the preliminary data for a separate proposal that investigates the biocompatibility, mechanical properties, and in vivo use for cartilage engineering applications.Broader ImpactThe proposed work will improve technologies for treating cartilage damaged from disease or injury. In addition, the methodology developed here can be extended for use in other applications such as bone or soft tissue grafts and for the design of multicellular tissues such the liver or vascularized organs. The PI is committed to the recruitment and retention of underrepresented groups in engineering and will engage in individual and group mentoring of female students (high school, undergraduate, and graduate). As part of the Women in Engineering Program, she is actively involved with the graduate mentoring program and is developing a laboratory module to introduce high school students to a high-throughput technique used to evaluate tissue engineering scaffolds. Undergraduate students from underrepresented groups will be recruited through the Louis Stokes Alliance for Minority Participation (LSAMP) Indiana to participate in research during the summer and academic year. The work will also train a female graduate student and mentor her through the process of obtaining a faculty position where she will serve as a role model and mentor to future students. The research will be integrated into the development of undergraduate and graduate level courses on tissue engineering and protein engineering. These courses will emphasize criticalanalysis and introduce students to cutting edge technologies through the use of primary literature papers.