Protein Chaperone Nanoparticles - Abiotic Mimics of Heat Shock Proteins

该奖项由材料研究部生物材料项目颁发，旨在开发新型、低成本、非生物、热响应的聚丙烯酰胺水凝胶纳米颗粒，该纳米颗粒具有类似伴侣的活性，可以在高温下稳定蛋白质。这种类似伴侣的功能源于合成聚合物纳米颗粒的两个“工程”特性：1)固有的抗体样蛋白质亲和力；2)较低的临界溶液温度（LCST），可用于在高温下捕获蛋白质，防止其聚集和变性，并在冷却到LCST以下时释放蛋白质，而无需添加添加剂，并保留蛋白质在溶液中的整体功能。创造“智能”合成聚合物分子伴侣的概念，其中合成聚合物纳米颗粒的抗体样蛋白质亲和力被用来通过抑制变性和/或蛋白质-蛋白质聚集以及由此导致的活性丧失来稳定目标蛋白质。合成聚合物纳米颗粒的第二个“智能”功能来自于它对温度的热响应。聚合物在温度高于其较低的临界溶液温度时处于崩溃状态，此时它具有蛋白质结合亲和力。这两种独特的聚合物特性使纳米颗粒的蛋白质结合亲和性得以工程化，从而使其随温度的变化而打开或关闭。一种应用是纳米颗粒，它可以在高温下隔离和稳定目标蛋白质，因为蛋白质在高温下是脆弱的，但在室温下对蛋白质几乎没有亲和力，因此不会妨碍蛋白质的功能。具有这种特性的“智能”材料可以通过保护蛋白质不变性而得到应用。它还可以帮助降低蛋白质治疗和诊断的成本，这在一定程度上是由于药物在运输和储存过程中保留了功效。该提案将吸引研究生、本科生和高中生参与一个跨学科的研究项目，涵盖聚合物合成、材料化学、生物学和生物技术。此外，该项目将为学生提供一个与工业合作者一起解决实际问题的机会，这可能对全球卫生保健的提供产生深远影响。蛋白质是由所有生命系统产生的大型生物聚合物。它们在所有生物过程中起着至关重要的作用，包括调节过程、免疫系统、所有生化反应的催化以及其他功能和特性。尽管它们很复杂，但分子生物学和生物技术的进步使蛋白质很容易获得。这些“工程”蛋白质现在被大规模生产并用于远远超出其预期生物功能的应用。这些应用包括治疗和诊断，以及增值化学品的合成。然而，蛋白质有一些限制。当超出生理温度和ph条件时，它们不稳定。特别是在室温以上的条件下，它们通常不稳定，这种温度敏感性会限制蛋白质的使用，特别是在不易获得冷藏设备的情况下。维持蛋白质的功能取决于冷库设施网络的可用性，这将在运输、储存和处理过程中提供最佳的低温。大自然进化出了保护蛋白质不受高温影响的策略。一类统称为热休克蛋白的生物大分子，可以“保护”脆弱的蛋白质在高温下不丧失功能。这项提议的研究是开发简单，低成本的合成聚合物，可以模仿热休克蛋白的行为。这些“工程化的”合成聚合物纳米颗粒被设计成通过隔离蛋白质来“保护”蛋白质在高温下不变性。该提案将为从研究生到高中水平的学生提供教育和培训机会，参与跨学科的研究项目，涵盖许多科学领域，如聚合物合成、材料化学、生物技术和生物学。此外，该项目将为学生提供与工业合作者合作的机会，并接受培训，不仅为他们成为下一代科学家做好准备，而且为他们提供在工业中工作的机会。

This award by the Biomaterials program in the Division of Materials Research is to develop novel, low cost, abiotic, thermally responsive polyacrylamide hydrogel nanoparticles with chaperone-like activity to stabilize proteins at elevated temperatures. The chaperone-like function arises from two 'engineered' properties of the synthetic polymer nanoparticles: 1) an intrinsic antibody-like protein affinity; and 2) a lower critical solution temperature (LCST), which can be used to trap protein at elevated temperatures, preventing its aggregation and denaturation, and release of the protein upon cooling below the LCST without the need for additives and preserving the overall function of the protein in solution. The concept of creating 'smart' synthetic polymer molecular chaperones, where the antibody-like protein affinity of synthetic polymer nanoparticles is utilized to stabilize a target protein by inhibiting denaturation and/or protein-protein aggregation and the resulting loss of activity. The second 'smart' function of the synthetic polymer nanoparticles arises from its thermal response to temperature. The polymer is in a collapsed state at a temperature above its lower critical solution temperature, where it has protein binding affinity. These two unique polymer properties allow engineering the protein binding affinity of the nanoparticle so that it is switched on and off in response to temperature. One application would be a nanoparticle that sequesters and stabilizes a target protein at elevated temperatures, where the protein is vulnerable, but that has little or no affinity for the protein at room temperature so as to not impede the proteins function. A 'smart' material with this property would find applications by protecting proteins from denaturation. It could also help reduce the cost of protein therapeutics and diagnostics, which arise in part due to the retention of efficacy of the drugs during transportation and storage. This proposal will engage graduate students, undergraduates and high school students in an interdisciplinary research program that spans polymer synthesis, materials chemistry, biology and biotechnology. Additionally, the project will provide students with an opportunity to work with industrial collaborators on practical problems, which could have profound impact on the world-wide delivery of health care. Proteins are large biopolymers produced by all living systems. They play an essential role in all biological processes including regulatory processes, the immune system, catalysis of all biochemical reactions among other functions and properties. Despite their complexity, advances in molecular biology and biotechnology have made proteins readily available. These 'engineered' proteins are now produced and used on a large scale for applications that go far beyond their intended biological functions. These applications include therapeutics and diagnostics, and synthesis of value-added chemicals. Proteins, however, have several limitations. They are not stable when taken beyond physiological conditions of temperature and pH. In particular, they are often unstable at conditions above room temperature, and this temperature sensitivity can limit the use of proteins particularly where refrigeration facilities are not easily available. Maintaining protein functions depend on the availability of a network of cold storage facilities, which will provide optimal cold temperatures during transport, storage, and handling. Nature has evolved strategies to protect proteins from elevated temperatures. A class of biomacromolecules collectively referred to as heat shock proteins, 'protect' vulnerable proteins against loss of function at elevated temperatures. This proposed study is in developing simple, low cost synthetic polymers that can mimic the behavior of heat shock proteins. These 'engineered' synthetic polymer nanoparticles are being designed to 'protect' proteins from denaturation at elevated temperature by sequestering them. This proposal will provide educational and training opportunities to students from graduate to high school levels in an interdisciplinary research program that spans many scientific fields such as polymer synthesis, materials chemistry, biotechnology and biology. In addition, this project will provide students with opportunity to work with industrial collaborators and receive training not only in preparing them as the future generation of scientists but also providing them with opportunities to work in industry.