Self-assembling Peptide Nanofiber Hydrogels for Delivery of Proteins and Cells

描述（由申请人提供）：本提案开发了一种纳米结构的细胞外基质模拟物，由自组装肽制备，我们称之为“多结构域肽”或mdp。MDPs自组装成纳米纤维，可以触发形成水凝胶。由于多肽易于制备并且具有明确的设计标准，因此可以制备许多MDP结构的变体，这使我们能够定制1)纤维自组装的条件（包括与细胞培养和体内应用兼容的条件），2)处理和注射性的关键机械性能，3)细胞化学信息的呈现，以及4)控制生物降解。这种特殊的特性组合将在这里开发，以创造用于包裹和递送细胞、蛋白质和小分子药物的仿生支架。我们的工作最终将在体内应用，使用这种纳米结构的水凝胶进行牙齿再生。预计纳米纤维将被证明是一种适用于细胞、蛋白质和小分子药物的可注射、局部、同时递送方法，将积极协助指导细胞活动。最后，在MDP基质发挥作用后，它会降解，只留下再生组织。这种基质将在未来的组织工程策略（包括但不限于牙齿再生）中发挥关键作用，这需要一种智能支架材料来组织组成细胞和药物，直到身体自身的再生能力能够接管。我们的建议分为四个目标。目的1将确定MDP纳米纤维的设计、灵活性和制备方法。目的2将优化MDP纳米纤维的三维细胞包裹，细胞传递和细胞介导的生物降解。Aim 3将开发一系列纳米纤维凝胶，这些凝胶将在时间和空间上传递生长因子和其他小分子。目的4将在体内测试上述纳米纤维水凝胶促进牙齿再生的能力。这项高度转化的研究将应用新的组织工程和纳米技术概念来设计多结构域肽水凝胶，作为再生组织的通用支架（在这里测试了牙本质-牙髓复合体的再生）。通过结合化学、材料科学、纳米技术、细胞生物学和临床牙科方面的专业知识，我们将生成数据，为在人体临床试验中测试这些水凝胶的进一步研究提供框架。

DESCRIPTION (provided by applicant): This proposal develops a nanostructured mimic of extracellular matrix prepared from a self-assembling peptide we call "Multidomain Peptides" or MDPs. The MDPs self-assemble into nanofibers that can be triggered to form a hydrogel. Because the peptides are easy to prepare and have a well defined design criteria many variations on the MDP architecture can be prepared which allow us to tailor 1) the conditions under which the fibers self-assemble (including conditions compatible with cell culture and in vivo applications), 2) the mechanical properties critical for handling and injectability, 3) the presentation of chemical information for cells, and 4) controlled biodegradation. This exceptional combination of properties will be developed here to create biomimetic scaffolds for the entrapment and delivery of cells, proteins and small molecule drugs. Our work will culminate with an in vivo application which uses this nanostructured hydrogel for dental regeneration. It is expected that the nanofibers will prove to be suitable as an injectable, localized, simultaneous delivery method for cells, proteins and small molecule drugs which will actively assist in directing cellular activity. Finally, after the MDP matrix has played its role it will degrade leaving behind only regenerated tissue. Such a matrix will play a critical role in future tissue engineering strategies (including, but not limited to, dental regeneration) which require a smart scaffolding material to organize the constituent cells and drugs until the body's own regenerative ability can take over. Our proposal is organized into four aims. Aim 1 will determine the design, flexibility and methods used to prepare MDP nanofibers. Aim 2 will optimize MDP nanofibers for three dimensional cell entrapment, cell delivery and cell mediated biodegradation. Aim 3 will develop a series of nanofibrous gels which will deliver growth factors and other small molecules localized in time and space. Aim 4 will test the above developed nanofibrous hydrogels ability to promote dental regeneration in vivo. This highly translational research will apply novel tissue engineering and nanotechnology concepts to the design of multidomain peptide hydrogels intended as an all-purpose scaffold for the regeneration tissue (tested here on the regeneration of the dentin-pulp complex). By combining expertise in chemistry, materials sciences, nanotechnology, cell biology and clinical dentistry we will generate data that will provide the framework for further studies testing these hydrogels in human clinical trials. PUBLIC HEALTH RELEVANCE: One of the most exciting areas of medical research is tissue engineering which promises to supplement our own regenerative ability to allow us to replace or re-grow damaged or diseased tissues and organs. Researchers use appropriate cell lines, growth factors and drugs which are organized by a synthetic matrix. In this proposal we describe an interdisciplinary approach to the design and optimization of a nanostructured matrix made from synthetic proteins. This matrix will entrap cells, proteins and drugs and allow them to be delivered together by syringe to the site necessary.