Biodegradable Micelles for Liver-Targeted Gene Delivery

项目摘要 该提案的总体目标是开发生物相容性，生物降解性和自我- 组装共聚物/DNA胶束以实现有效的肝靶向基因递送。肝脏是一个 由于转基因的进入， 产品的体循环，因为它是许多代谢遗传疾病的网站， 病毒感染和恶性肿瘤。目前，肝脏靶向基因转移的全部潜力是 缺乏安全有效的基因载体。具有DNA/聚阳离子的聚合物胶束 复合核和亲水冠是一种有前途的肝靶向基因载体 交付.这些DNA包封胶束表现出几个有利肝脏的理想特征， 靶向基因递送，例如小尺寸（80-100 nm），减少与生物活性物质的相互作用， 成分，延长血液循环，毒性低。新型PEG-b-PPA/DNA胶束 显示出高的DNA结合能力、体外转染效率、低的细胞毒性和良好的 组织生物相容性在这项研究中，我们将（1）合成和表征一个小型文库， 具有改进的复合物稳定性、胶体稳定性、细胞内DNA的PEG-b-PPA/DNA胶束 释放，内体逃逸和肝细胞靶向能力;（2）表征转染 在大鼠原代肝细胞、枯否细胞和正常大鼠中的效率和细胞毒性 胆管细胞的这一系列结构不同的共聚物/胶束，并与 胶束结构;（3）优化给药参数，实现高效肝基因 非分泌性蛋白（荧光素酶）和分泌性蛋白（干扰素-a2 b）的表达。 这将证明该递送策略用于表达蛋白质的广泛用途。 用于全身分布和局部肝脏特异性疾病。机制研究 将在体外和体内进行，以了解细胞外和细胞内转运 胶束。这项研究整合了高分子化学，生物材料设计， 分子/细胞生物学和临床科学。它代表了一个系统的设计和优化 在多个层面上的基因传递策略。本研究将为今后的临床应用奠定基础 聚合物胶束在肝靶向基因治疗中的应用。项目叙述 该提案的总体目标是开发安全有效的非病毒纳米颗粒 将基因传递到肝脏的载体。如果这项研究取得成功，这些新的 基因载体在治疗遗传性和代谢性肝脏方面具有广阔的临床应用前景 疾病、肝癌、病毒性肝炎和系统性疾病，如血友病A和B。

Project Summary The overall objective of this proposal is to develop biocompatible, biodegradable and self- assembling copolymer/DNA micelles to achieve efficient liver-targeted gene delivery. Liver is a critically important target for gene medicine applications because of the access of the transgene product to systemic circulation, and because it is the site of many metabolic genetic disorders, viral infection and malignancies. At present, the full potential of liver-targeted gene transfer is hindered by a lack of safe and efficient gene carriers. Polymeric micelles with a DNA/polycation complex core and a hydrophilic corona represent a promising carrier for liver-targeted gene delivery. These DNA-encapsulating micelles exhibit several desirable features that favor liver- targeted gene delivery, such as small size (80-100 nm), reduced interaction with biological components, prolonged circulation in blood, and low toxicity. Novel PEG-b-PPA/DNA micelles exhibit high DNA binding capacity, in vitro transfection efficiency, low cytotoxicity and good tissue biocompatibility. In this study, we will (1) synthesize and characterize a mini-library of PEG-b-PPA/DNA micelles with improved complex stability, colloidal stability, intracellular DNA release, endosomal escape, and hepatocyte-targeting ability; (2) characterize the transfection efficiency and cytotoxicity in rat primary hepatocytes, Kupffer cells and normal rat cholangiocytes for this series of structurally distinct copolymers/micelles, and correlate with micelle structures; (3) optimize the administration parameters to achieve efficient liver gene expression for both a non-secretory protein (luciferase) and a secretory protein (interferon-a2b). This will demonstrate the broad utility of this delivery strategy for expression of proteins intended for systemic distribution and for localized liver-specific diseases. Mechanistic studies will be performed in vitro and in vivo to understand the extracellular and intracellular transport of the micelles. This study integrates expertise in polymer chemistry, biomaterial design, molecular/cell biology and clinical sciences. It represents a systematic design and optimization of gene delivery strategies at multiple levels. This study will lay the foundation for future clinical application of polymeric micelles for liver-targeted gene therapy. Project Narrative The overall objective of this proposal is to develop safe and efficient non-viral nanoparticle carriers for gene delivery to the liver. Should this proposed study be successful, these new gene carriers will find wide clinical applications for treating inherited and metabolic liver diseases, liver cancer, viral hepatitis, and systemic diseases, like hemophilia A and B.