New Polymeric Carriers for Pulmonary Gene Delivery

用于肺部基因传递的新型聚合物载体

• 批准号: 6821824
• 负责人: DEXI LIU
• 金额: $ 35.77万
• 依托单位: UNIVERSITY OF PITTSBURGH AT PITTSBURGH
• 依托单位国家: 美国
• 财政年份: 2004
• 资助国家: 美国
• 起止时间: 2004-07-01 至 2008-04-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6821824
• 关键词: CpG islands; biodegradable product; biomaterial compatibility; biotechnology; cell adhesion molecules; gene delivery system; gene therapy; hydropathy; immune response; inflammation; inhalation drug administration; laboratory mouse; nucleic acid purification; polymers; receptor mediated endocytosis; respiratory epithelium; technology /technique development; transfection

DESCRIPTION (provided by applicant): Gene therapy has the potential for treating various lung diseases. However, its clinical use is unrealized because of the lack of a safe and efficient gene delivery technology. Current cationic polymers have low transfection efficiencies and are toxic to the lungs due to excessive charges and non-biodegradable nature. Also, unmethylated CpG groups that exist in plasmid DNA could trigger an inflammatory response when it is delivered as complex with a carrier. We hypothesize that a safer and more efficient nonviral gene delivery system can be derived by designing multifunctional, more biocompatable carriers and gene sequences that have minimal size and low content of unmethylated CpG groups. We described here a new synthetic route that led to a class of polyhydroxylalkyleneamine with adjustable charge densities, variable spacing groups and a high content of hindered nitrogens with lowered pKa. Cell and airway transfection using DNA/polymer complexes showed several fold higher transfection activity than those using polyethylenimine/DNA complexes. The new polymers showed much reduced toxicity than polyethylenimine. More importantly, reducible disulfide bonds and hydrophobic groups can be added to backbones to make these polymers biodegradable and more potent, respectively. We propose to identify most active and least toxic polymers by adjusting polymer properties such as DNA condensation, membrane activity and biodegradability. We also propose to better understand this new gene delivery system through detailed characterization of physicochemical properties, mechanism of transfection and metabolism profiles of these polymers in vitro and in vivo. In addition, polymer/DNA complexes dressed with antibodies specific to ICAM-1 will be tested for their effect to reduce the surface charges of the polymer/DNA complex and to trigger specific cell uptake via receptor-mediated endocytosis. Lastly, a DNA fragment containing a small-sized functional gene expression cassette with minimal unmethylated CpG contents will be tested in vivo to reduce inflammation response. Combining these innovations, we will establish a safe and efficient non-viral gene delivery system suitable for the airway delivery and potential applications for other organs.

描述（由申请人提供）：基因疗法具有治疗多种肺部疾病的潜力。然而，由于缺乏一种安全有效的基因传递技术，其临床应用尚未实现。目前的阳离子聚合物转染效率低，并且由于电荷过多和不可生物降解的性质而对肺部有毒。此外，存在于质粒DNA中的未甲基化CpG组在与载体复合物一起递送时可能引发炎症反应。我们假设，通过设计多功能、更具生物相容性的载体和具有最小尺寸和低含量未甲基化CpG基团的基因序列，可以衍生出更安全、更有效的非病毒基因传递系统。本文描述了一种新的合成路线，可以得到一类电荷密度可调、基团间距可变、阻碍氮含量高、pKa较低的聚羟基亚烯胺。使用DNA/聚合物复合物转染细胞和气道的转染活性比使用聚乙烯亚胺/DNA复合物的转染活性高几倍。新聚合物的毒性比聚乙烯亚胺低得多。更重要的是，可还原二硫键和疏水性基团可以分别添加到骨架上，使这些聚合物可生物降解和更有效。我们建议通过调整聚合物的性质，如DNA缩聚，膜活性和生物降解性来确定最活跃和最无毒的聚合物。我们还建议通过详细表征这些聚合物的物理化学性质，转染机制和体外和体内代谢谱来更好地了解这种新的基因传递系统。此外，将测试与ICAM-1特异性抗体修饰的聚合物/DNA复合物的效果，以减少聚合物/DNA复合物的表面电荷，并通过受体介导的内噬作用触发特定的细胞摄取。最后，将在体内测试含有小尺寸功能性基因表达盒的DNA片段，该DNA片段具有最小的未甲基化CpG含量，以减少炎症反应。结合这些创新，我们将建立一种安全高效的非病毒基因传递系统，适用于气道传递和其他器官的潜在应用。