Controlled Release of DNA from Surfaces

描述（由申请人提供）：我们研究的广泛目标是设计控制生物医学材料和设备表面DNA分布和释放的材料。如何安全、高效、可控地将DNA传递到细胞中，是基因治疗取得临床成功的一个巨大挑战和障碍。传统材料不能满足这一快速发展领域的技术或临床需求，特别是对于需要从表面释放或可预测的多基因序列管理的应用。可降解聚合物基质可以被设计成维持质粒DNA的释放，使用类似于先前开发的蛋白质递送策略。然而，这些散装材料缺乏控制材料表面附近质粒（或多个质粒）分布所需的复杂性。我们已经开发出可降解的多层材料，可以在纳米尺度上控制包括DNA在内的多阴离子的结合和随后的释放。这一提议是基于这样一个假设，即结合质粒DNA的多层聚合物组件可以用来引导DNA释放到生长在这些材料表面的细胞中。以下具体目标旨在详尽地评估这一假设。它们是：1)采用一层一层的方法将质粒DNA纳入水解可降解的聚电解质膜中；2)表征含质粒膜的物理和化学侵蚀特征，并建立释放DNA的结构完整性；3)评估功能含DNA膜作为细胞附着的底物和指导贴壁细胞转染的平台。控制质粒DNA从生物医学材料表面分布和释放的复杂新材料将对局部基因治疗的发展和基因治疗的持续推进进入临床产生深远的影响。

DESCRIPTION (provided by applicant): The broad goal of our research is the design of materials that control the distribution and release of DNA from the surfaces of biomedical materials and devices. The safe, efficient, and controlled delivery of DNA to cells presents a formidable challenge and an obstacle to the clinical success of gene therapy. Conventional materials do not meet the technical or clinical demands of this rapidly growing field, particularly for applications that require release from surfaces or the predictable administration of multiple gene sequences. Degradable polymer matrices can be engineered to sustain the release of plasmid DNA using strategies similar to those previously developed for the delivery of proteins. However, these bulk materials lack the sophistication required to control the distribution of plasmid (or multiple plasmids) near the surface of the material. We have developed degradable multilayered materials that provide nanometer-scale control over the incorporation and subsequent release of polyanions, including DNA. This proposal is based on the hypothesis that multilayered polymer assemblies incorporating plasmid DNA can be used to direct the release of DNA to cells growing on the surfaces of these materials. The following Specific Aims are designed to exhaustively evaluate this hypothesis. They are: 1) To incorporate plasmid DNA into hydrolytically degradable polyelectrolyte films using a layer-by-layer approach, 2) To characterize the physical and chemical erosion profiles of plasmid-containing films and establish the structural integrity of released DNA, and 3) To evaluate functional DNA-containing films as substrates for cell attachment and as platforms to direct the transfection of adherent cells. Sophisticated new materials that control the distribution and release of plasmid DNA from the surfaces of biomedical materials will have a profound impact on the development of localized gene therapies and the continued advance of gene therapy into the clinic.