Multifunctional Protein Nanocapsules for Targeted Delivery

描述（由申请人提供）：随着对分子水平细胞过程的更好理解，可以在纳米长度尺度上设计新型材料，利用这些新知识有效地递送治疗性化合物。但是，在综合这些小实体方面的限制往往妨碍了合理合并多种功能的能力，这反过来又限制了现有的交付战略。值得注意的是，我们提出的递送系统可以独特地解决小纳米级系统的一些限制，从而潜在地扩展纳米级递送系统的可行性。这项研究的目的是将多种功能整合到25纳米蛋白质纳米颗粒中，并测试其在癌细胞中靶向药物递送的潜力。这可以通过显著减少所需药物的量，扩大其治疗能力，允许更好地控制靶向和释放以及减少副作用来潜在地提高给定药物的有效性。我们的合成策略包括基因设计蛋白质纳米粒子的嵌合体，这使得纳米级结构能够以相对直接的方式进行专门定制。这项工作将首次研究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递送的可行性。我们假设，当细胞靶向、药物包封、ph响应解离和药物释放等多种特性在每个蛋白质纳米颗粒内结合时，癌细胞的细胞毒性将达到最大。为了验证这一假设，我们提出了以下具体目标：(1)制造具有癌症靶向配体的载药、ph响应的蛋白质纳米颗粒；(2)确定乳腺癌细胞毒性和体外剂量反应谱的最佳条件；(3)将内吞作用、区室运输和药物释放机制与纳米颗粒特性和细胞毒性相协调。这项工作不仅将发展多功能蛋白质纳米颗粒药物递送技术，而且将使E2支架作为确定一般递送原则的模型成为可能。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，我们的目标疾病在这项拟议的工作是乳腺癌，这将是用蛋白包裹的阿霉素治疗。虽然阿霉素是一种常规的治疗方法，但它对患者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颗粒药物递送的一般策略，这些策略只会增加癌细胞的细胞毒性，同时减少总剂量和严重的副作用。

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.