Shape Control and Transfection of Self-assembled Polymer-DNA Nanoparticles

描述（由申请人提供）：本研究的总体目标是建立对自组装DNA纳米颗粒形状控制的机制理解，并验证纳米颗粒形状可以影响其细胞摄取、细胞内运输和基因传递效率的假设。最近的几项研究表明，病毒颗粒和各种合成纳米颗粒的形态是其运输特性和生物学功能的重要决定因素。我们已经开发了一种方法，用于自组装含有dna的纳米颗粒，这些纳米颗粒具有几种不同的形状（球形，棒状和蠕虫状），类似于一些用于基因转染的病毒颗粒。这些纳米颗粒是了解dna诱导的自组装机制以及纳米颗粒形状对其稳定性、细胞-纳米颗粒相互作用、转染效率和体内运输动力学的影响的理想系统。利用这一探索性资助，我们计划(1)确定有效控制纳米颗粒形状和大小的关键实验参数，并利用实验和计算模型相结合的方法了解聚乙二醇化聚合DNA缩聚过程中形状控制的机制；(2)在体外和体内肝脏靶向基因传递模型中，证明纳米颗粒形状对细胞摄取、细胞内运输和转染效率的依赖性。本研究将提供对DNA/ peg -多阳离子纳米颗粒自组装的主要驱动力的机制理解，并确定涉及其形状控制的关键参数。它将提供一种有效的方法来控制DNA/聚合物纳米颗粒的大小和形状，可适用于各种聚乙二醇化基因载体合成纳米颗粒，对其形状或形态具有高度的控制。

DESCRIPTION (provided by applicant): The overall objective of this study is to develop a mechanistic understanding of shape control of self-assembled DNA nanoparticles, and to test the hypothesis that nanoparticle shape can influence their cellular uptake, intracellular trafficking and gene delivery efficiency. Several recent studies have raised the prospect that the morphology of virus particles and various types of synthetic nanoparticles is an important determinant for their transport properties and biological functions. We have developed a method for the self-assembly of DNA-containing nanoparticles with several distinct shapes (spherical, rod-like and worm-like) similar to some viral particles for the purpose of gene transfection. Such nanoparticles are ideal systems for understanding the mechanism of DNA-induced self-assembly and the effect of nanoparticle shape on their stability, cell- nanoparticle interactions, transfection efficiency and in vivo transport kinetics. With this Exploratory Grant, we plan (1) to determine the key experimental parameters that effectively control the shape and size of nanoparticles, and to understand the mechanism of shape control in DNA condensation by PEGylated polycations using a combined experimental and computational modeling approach; and (2) to demonstrate nanoparticle shape dependence in cellular uptake, intracellular trafficking and transfection efficiency in vitro and in vivo in a liver-targeted gene delivery model. This study will provide a mechanistic understanding of the major driving forces for the self-assembly of DNA/PEG-polycation nanoparticles and identify key parameters involved in their shape control. It will offer an effective method to control the size and shape of DNA/polymer nanoparticles that can be applicable to a variety of PEGylated gene carriers in synthesizing nanoparticles with high degree of control over their shapes or morphologies.