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

描述（由申请人提供）：该提案开发了一种由自组装肽制备的细胞外基质的纳米结构模拟物，我们称之为“多结构域肽”或MDP。MDP自组装成纳米纤维，其可以被触发以形成水凝胶。因为肽易于制备并且具有明确的设计标准，所以可以制备MDP结构的许多变化，这允许我们定制1）纤维自组装的条件（包括与细胞培养和体内应用相容的条件），2）对于处理和可注射性至关重要的机械性能，3）细胞的化学信息的呈现，（4）可控生物降解。这种特殊的特性组合将在这里开发，以创建用于捕获和递送细胞，蛋白质和小分子药物的仿生支架。我们的工作将最终在体内应用，使用这种纳米结构的水凝胶牙齿再生。预计纳米纤维将被证明适合作为细胞、蛋白质和小分子药物的可注射、局部化、同时递送方法，这将积极地帮助指导细胞活性。最后，在MDP基质发挥作用后，它将降解，仅留下再生组织。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，这些策略需要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可以接管。我们的建议分为四个目标。目标1将确定用于制备MDP纳米纤维的设计、灵活性和方法。目的2优化MDP纳米纤维的三维细胞包埋、细胞递送和细胞介导的生物降解。目标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提供生长因子和其他小分子。目的4将测试上述开发的纳米纤维水凝胶在体内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学方面的专业知识，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。 公共卫生相关性：医学研究中最令人兴奋的领域之一是组织工程，它有望补充我们自己的再生能力，使我们能够替换或重新生长受损或患病的组织和器官。研究人员使用适当的细胞系，生长因子和药物，它们由合成基质组织。在这个建议中，我们描述了一个跨学科的方法来设计和优化的纳米结构矩阵由合成蛋白质。该基质将捕获细胞、蛋白质和药物，并允许它们通过注射器一起递送到必要的部位。

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.