Multifunctional Protein Nanocapsules for Targeted Delivery

描述(由申请人提供)：随着在分子水平上更好地了解细胞过程，可以在纳米尺度上设计新材料，利用这一新知识有效地提供治疗性化合物。然而，在综合这些小实体方面的限制往往排除了合理地结合多种功能的能力，这反过来又限制了可用的交付战略。值得注意的是，我们提出的递送系统可以独一无二地解决小纳米系统的一些限制，从而潜在地扩展了纳米递送系统的可行性。这项拟议的研究的目标是将多种功能整合到25纳米蛋白质纳米颗粒中，并测试它们在癌细胞中靶向药物输送的潜力。这可能会显著减少所需的药物数量，扩大其治疗能力，允许更好地控制靶向和释放，并减少副作用，从而潜在地提高给定药物的有效性。我们的合成策略包括从基因上设计蛋白质纳米颗粒的嵌合体，这使得纳米尺度的架构能够以相对简单的方式进行专门的定制。这项拟议的工作将首次调查乳腺癌细胞对这些蛋白质纳米颗粒的反应，并测试使用这些多功能支架改善阿霉素治疗输送的可行性。我们假设，当细胞靶向、药物包裹、pH响应解离和药物释放的多种性质在每个蛋白质纳米颗粒中结合时，对癌细胞的细胞毒性将是最大的。为了验证这一假设，我们提出了以下具体目标：(1)制备显示癌症靶向配体的载药、pH响应的蛋白质纳米粒，(2)确定乳腺癌细胞的细胞毒性和体外剂量-反应曲线的最佳条件，以及(3)将内吞、间隔转运和药物释放机制与纳米粒特性和细胞毒性相协调。这项拟议的工作不仅将开发多功能蛋白质纳米颗粒在药物输送中的技术，而且将使E2支架能够用作确定一般输送原理的模型。这包括确定影响细胞相互作用和行为的目标纳米颗粒的结构和性质。此外，在这项拟议的工作中，我们的目标疾病是乳腺癌，将使用蛋白质包裹的阿霉素进行治疗。虽然阿霉素是一种常规的治疗方法，但它在患者中表现出剂量依赖性的心脏毒性。从这项研究中获得的信息可以确定纳米药物输送的一般策略，这些策略只增加癌细胞的细胞毒性，同时减少总剂量和严重的副作用。 公共卫生相关性：用于靶向递送的多功能蛋白质纳米胶囊在创造一类新的纳米药物载体方面，治疗递送的新治疗策略的范围将被拓宽。这有可能扩大疾病治疗的疗效，促进再生医学。

DESCRIPTION (provided by applicant): As a better understanding of cellular processes at the molecular level is gained, novel materials can be designed at the nanometer length scale which exploits this new knowledge to effectively deliver therapeutic compounds. However, limitations in synthesizing such small entities often preclude the ability to rationally incorporate multiple functions, which in turn restricts available delivery strategies. Significantly, our proposed delivery system can uniquely address some of these limitations of small nanoscale systems, thereby potentially extending the feasibility of nanoscale delivery systems. The goal of this proposed investigation is to incorporate multiple functionalities into 25-nm protein nanoparticles and test their potential for targeted drug delivery in cancer cells. This can potentially increase the effectiveness of a given drug by significantly decreasing the amount of drug needed, expanding its therapeutic capabilities, allowing greater control over targeting and release, and decreasing side effects. Our synthesis strategy involves genetically designing chimeras of protein nanoparticles, which enables the nanoscale architecture to be specifically tailored in a relatively straightforward manner. This proposed work will, for the first time, investigate the response of breast cancer cells to these protein nanoparticles and test the feasibility of using these multifunctional scaffolds for improving therapeutic delivery of doxorubicin. We hypothesize that cytotoxicity in cancer cells will be greatest when the multiple properties of cellular targeting, drug encapsulation, and pH-responsive dissociation and drug release are combined within each protein nanoparticle. To test this hypothesis, we propose the following specific aims: (1) Fabricate drug-loaded, pH-responsive protein nanoparticles that display cancer-targeting ligand, (2) Determine optimal conditions for cytotoxicity and in vitro dose-response profiles in breast cancer cells, and (3) Reconcile the mechanisms of endocytosis, compartmental trafficking, and drug release with nanoparticle characteristics and cytotoxicity. This proposed work not only will develop the technology of multifunctional protein nanoparticles in drug delivery, but will enable the use of the E2 scaffold as a model for determining general delivery principles. This includes identifying the structures and properties of targeted nanoparticles which affect cellular interaction and behavior. Furthermore, our target disease in this proposed work is breast cancer, which will be treated with protein-encapsulated doxorubicin. Although doxorubicin is a conventional line of treatment, it exhibits dose-dependent cardiotoxicity in patients. Information learned from this investigation could identify general strategies in nanoparticulate drug delivery that increase cytotoxicity in only cancer cells while decreasing overall doses and severe side-effects. PUBLIC HEALTH RELEVANCE: Multifunctional Protein Nanocapsules for Targeted Delivery In creating a new class of nanoscale drug carriers, the scope of novel therapeutic strategies in therapeutic delivery will be broadened. This has the potential to expand the efficacy of disease treatment and promote regenerative medicine.