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

[09:27 . 100]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。“设计带有诱导或增强成体干细胞分化为软骨细胞线索的材料，将改善患有骨关节炎（一种影响关节软骨的退行性疾病）的患者的治疗选择。健康的软骨保护承重骨骼，并作为关节表面运动的润滑剂，但软骨一旦受损，再生潜力有限。利用成体干细胞植入支架，开发组织工程软骨替代物的研究越来越受到关注。这些细胞通常在体外使用可溶性生长因子和化合物分化。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。开发包含靶向细胞分化线索的材料可以规避这些问题，并且具有促进复杂三维组织的设计和构建的附加好处。建议的工作将研究从软骨生长因子衍生的肽序列，并已显示在其他生物系统中引发活性。这项工作的目标是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)利用实验设计技术研究协同效应和软骨表型的维持，以及3)开发一种新的基于蛋白质的支架，并在三维支架的背景下证明这些肽的活性。该提案的结果将展示原理证明，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，将其建立为一般设计规则。未来的建议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，本文提出的工作将证明含有化学和光交联位点的新型基于树脂的蛋白质支架的实用性。这些结果将作为研究生物相容性、机械性能和软骨工程应用的体内使用的单独提案的初步数据。更广泛的影响拟议的工作将改进治疗因疾病或损伤而受损的软骨的技术。此外，这里开发的方法可以扩展到其他应用，如骨或软组织移植，以及多细胞组织（如肝脏或血管化器官）的设计。PI致力于招募和保留工程领域代表性不足的群体，并将对女学生（高中、本科和研究生）进行个人和团体指导。作为女性工程项目的一部分，她积极参与研究生指导项目，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，在夏季和学年期间参与研究。这项工作还将培训一名女研究生，并在获得教职的过程中指导她，在那里她将成为未来学生的榜样和导师。该研究将整合到组织工程和蛋白质工程的本科和研究生课程的开发中。这些课程将强调批判性分析，并通过使用原始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.