Collaborative Research: Design of Multifunctional Doubly-Fusogenic Liposomes to Deliver Therapeutics and Diagnostics

ID：MPS/DMR/BMAT(7623)1207022 PI：SOFU，Stavroula ORG：罗格斯大学ID：MPS/DMR/BMAT(7623)1206943 PI：Hall，Carol ORG：北卡罗来纳州立大学INTELLECTUCTUAL优点：目前提供有效控制晚期实体癌症的最有希望的策略是综合治疗。这一组合的一个潜在组成部分是抗血管治疗。这项工作的目标是设计静脉注射的脂质体纳米载体，它可以被编程为靶向肿瘤血管，同时保留健康部位，并释放化疗药物，传递放射性显像剂，或两者兼而有之。这将通过一种实验和理论相结合的方法来实现，以开发具有高度选择性的脂囊，该脂囊由一类新的双脂类膜组成，这种膜可以在细胞内快速广泛地释放阿霉素或传递正电子发射体。脂质体的高杀伤力是基于双重融合机制，只有在细胞内化时才能激活。该项目的创新之处在于选择单独的基本成分，以及它们协同工作的方式，以优化药物到适当地点的输送。另一项创新是使用分子水平的计算机模拟来探索脂质体参数的各种选择的后果，然后在实验室中进行试验，从而减少了通常情况下这类工作的反复试验步骤的数量。基本成分如下：PSMA(前列腺特异性膜抗原)是靶标，它存在于肿瘤血管中，而不存在于正常组织中。抗PSMA抗体是配体。脂质体由两种功能化的脂类组成：与抗PSMA抗体相连的聚乙二醇化的脂类和由促进与内膜融合的融合肽功能化的脂类。交付机制如下。在血液循环中，暴露的抗PSMA抗体导致选择性的新生血管靶向，同时将聚乙二醇化的脂类均匀分布在脂质体表面，掩盖融合肽。当肿瘤内皮细胞吞噬脂质体时，pH诱导的脂质相分离和脂体膜上结构域的形成激活了两种融合机制：(1)融合多肽成为未被遮盖的并结合到内吞体膜上；(2)脂质体结构域边界作为与内膜融合的成核部位。最终的结果是，脂质体将其货物直接释放到肿瘤内皮细胞的细胞质中，而不是内体，从而避免被包裹在内体途径中，并随后被溶酶体降解。它有三个目标：(1)开发一个经过实验证实的通用计算工具，以促进脂质体的设计，并测试关于不同组件在所提议的分级组装中的作用的假设。(2)设计含有抗PSMA配体和小分子融合肽的脂质体，并考察其功能的最佳条件。(3)证明装载阿霉素和Y-86的双融合脂质体显示：(A)选择性靶向肿瘤内皮类似物，(B)有效释放化疗药物和杀伤靶细胞，以及(C)提供足够数量的Y-86用于诊断应用。BROADER影响：由于晚期实体癌无法治愈，许多患者可以从拟议的研究中受益，该研究旨在开发显著延长患者寿命和改善患者预期的诊断和治疗方案？生活质量。这里进行的研究将得到强有力的教育部分的补充，包括培训两名女性研究生和几名分配给这个项目的本科生，将这项研究的几个主题整合到一个新启动的开放式高中设计项目中，为高中学生和他们的老师开展一般的外展和指导活动，以及为全国的女研究生和教师开展指导活动。特别是，这项为期6周的暑期外展计划将在罗格斯大学进行，旨在鼓励代表人数较少的少数族裔高中生投身科学和工程领域。该项目包括实践研究培训，由学术界和产业界的演讲者就与生物材料相关的当代问题进行的一系列讲座，以及参观邻近的制药行业。将编写突出这项研究的教育材料，包括介绍纳米技术和通过软材料提供药物的基础知识的POWER POINT演示文稿，以便在网上传播。

ID: MPS/DMR/BMAT(7623) 1207022 PI: Sofou, Stavroula ORG: Rutgers UniversityID: MPS/DMR/BMAT(7623) 1206943 PI: Hall, Carol ORG: NC State UniversityINTELLECTUAL MERIT: The most promising strategy at present to provide effective control of advanced solid cancer is a combination of therapies. A potential component of this combination is antivascular therapy. The goal of this work is to design iv-administered theranostic liposome nanocarriers that can be programmed to target tumor vasculature while sparing healthy sites and to release a chemotherapeutic agent, deliver a radioactive imaging agent or both. This will be accomplished through a combined experimental and theoretical approach to develop highly selective lipid vesicles composed of a new class of bi-lipid membranes that rapidly and extensively release doxorubicin intracellularly or deliver positron emitters. The high killing efficacy of the liposomes is based on a dual fusion mechanism that is activated only upon cellular internalization. The project's innovation lies in the choice of individual base components and the synergistic way that they work together to optimize delivery of the drug to the proper site. An additional innovation is the use of molecular level computer simulation to explore the consequences of various choices of liposome parameters "in silico" before trying them out in the lab, thus reducing the number of trial-and-error steps that would normally characterize this type of work . The base components are the following: PSMA (Prostate Specific Membrane Antigen), which is present on tumor vasculature but not in normal tissue, is the target. An anti-PSMA antibody is the ligand. The liposomes are comprised of two functionalized lipids: PEGylated lipids tethered to anti-PSMA antibodies and lipids functionalized with a fusion peptide that promotes fusion with the endosomal membrane. The mechanisms of delivery are the following. During circulation in the blood, the exposed anti-PSMA antibodies result in selective neovasculature targeting while uniformly distributed PEGylated lipids on the liposome surface mask the fusion peptides. Upon endocytosis of liposomes by tumor endothelial cells, pH-induced lipid phase-separation, and domain formation on liposome membranes activates two fusion mechanisms: (1) The fusion peptides become unmasked and bind to the endosome membrane, and (2) The liposomal domain boundaries serve as sites to nucleate fusion with the endosomal membrane. The net result is that the liposome releases its cargo directly into the cytoplasm of tumor endothelial cells, as opposed to the endosome, avoiding entrapment in the endosomal pathway and subsequent degradation by the lysosome. There are three aims: (1) Develop an experimentally informed general computational tool to facilitate the design of liposomes and to test hypotheses about the role of the different components in the proposed hierarchical assembly. (2) Engineer liposomes containing anti-PSMA ligands and small fusion peptides, and investigate the conditions in which the corresponding functionalities exhibit optimal behavior. (3) Demonstrate that dual-fusion liposomes loaded with doxorubicin and Y-86 exhibit: (a) selective targeting of tumor endothelium analogues, (b) effective release of chemotherapeutics and killing of targeted cells, and (c) delivery of sufficient amounts of Y-86 for diagnostic applications.BROADER IMPACTS: Since advanced solid cancer has no cure, many patients could benefit from the proposed research that aims to develop diagnostic and treatment protocols that significantly extend the life expectancy and improve patients? quality of life. The research pursued here will be supplemented by a strong educational component that includes training of two female graduate students and several undergraduate students assigned to this project, integration of several topics of this research in a newly launched open-ended senior design project, general outreach and mentoring activities for high school students and their teachers, and mentoring activities for women graduate students and faculty across the nation. In particular, the 6-week outreach summer program, which will be conducted at Rutgers University, aims to encourage underrepresented and minority high school students to follow a career in sciences and engineering. The program includes hands-on research training, a series of lectures given by speakers from academia and industry on contemporary issues related to biomaterials, and visits to neighboring pharmaceutical industries. Educational materials will be developed that highlight this research including a power point presentation introducing the basics of nanotechnology and drug delivery via soft materials for dissemination over the web.