Novel gene-silencing therapeutics for multidrug-resistant gram-negative pathogens

项目摘要/摘要 对新的抗菌剂的需求日益迫切。多重耐药病原体的比率继续上升 这一增长导致全世界出现严重的发病率和死亡率。此外，目前的管道 对于新的抗菌剂来说，仍然非常有限。美国传染病学会在他们的研究中发现 “坏虫子，不吃药”运动，一群对当前病原体的抗药性越来越强的病原体 抗生素。这一组包括革兰氏阴性病原体鲍曼不动杆菌和大肠杆菌。 抗生素发现和设计中的一种新范例最近被证明对许多 细菌。这一新方法基于一种名为多肽-磷二酸酯莫波利诺的平台技术。 齐聚物(PPMO)。PPMO是一种人工合成的DNA模拟物，它以序列特异性的反义方式与RNA结合 抑制细菌必需基因的表达。PPMO已经成功地被用来杀死 各种细菌病原体，包括革兰氏阴性菌、大肠杆菌、沙门氏菌 鼠伤寒杆菌、洋葱伯克霍尔德氏菌复合体和鲍曼不动杆菌。PPMO在培养中是杀菌的， 并在感染动物模型中减少菌血症并提高存活率。PPMO的效力比 许多传统的抗生素，如氨苄西林。该项目的目标是开发用于治疗的PPMO 用于对抗多重耐药的病原菌：大肠杆菌和鲍曼不动杆菌。具体的 目的是设计、生产和筛选针对多药耐药患者不同基因靶点的PPMO 病原菌为大肠杆菌和鲍曼不动杆菌。实验方法是针对途径中的基因，这些途径 已知的或怀疑对生物体的生长至关重要的，包括生物合成的基因 脂多糖、肽聚糖和脂肪酸。另一种方法是将PPMO用作附加语 治疗和针对特定的抗生素耐药性机制，以恢复对目前的敏感性 使用了抗生素。这项技术提供了方法上的优势，因为许多PPMO可以快速 合成并同时针对众多目标进行测试。这使得有可能将目标 单个生物体中的多个基因或针对多种病原体的PPMO鸡尾酒的开发。 该项目将确定大肠杆菌和鲍曼不动杆菌中的主要靶标PPMO，这些PPMO可以向前移动到前 临床和临床研究。

Project Summary/Abstract The need for new antimicrobials is increasingly urgent. The rate of multidrug resistant pathogens continues to increase leading to significant morbidity and mortality throughout the world. Furthermore, the current pipeline for new antimicrobials remains very narrow. The Infectious Diseases Society of America has identified in their "Bad Bugs, No Drugs" campaign, a group of pathogens that have become increasingly resistant to current antibiotics. This group includes the Gram-negative pathogens Acinetobacter baumannii and Escherichia coli. A new paradigm in antibiotic discovery and design has recently been shown effective against numerous bacteria. This new approach is based on a platform technology called peptide-phosphorodiamidate mopholino oligomers (PPMOs). PPMOs are synthetic DNA mimics that bind to RNA in a sequence-specific, antisense manner and inhibit expression of essential bacterial genes. PPMOs have already been used successfully to kill a variety of bacterial pathogens including the Gram-negative bacteria Escherichia coli, Salmonella typhimurium, Burkholderia cepacia complex and Acinetobacter baumannii. PPMOS are bactericidal in culture, and reduce bacteremia and improve survival in animal models of infection. PPMOs are more potent than many traditional antibiotics such as ampicillin. The goal of this project is to develop PPMOs for therapeutic use against the multidrug resistant pathogens Escherichia coli and Acinetobacter baumannii. The specific aims are to design, produce and screen PPMOS against various gene targets in the multidrug-resistant pathogens E. coli and A. baumannii. The experimental approach is to target genes in pathways that are known or suspected to be essential for the growth of the organism, including genes for biosynthesis of lipopolysaccharide, peptidoglycan, and fatty acids. Another approach will be to use PPMOs as adjunctive therapies and target specific antibiotic resistance mechanisms in order to restore susceptibility to currently used antibiotics. This technology provides a methodological advantage because many PPMOs can be rapidly synthesized and simultaneously tested against numerous targets. This allows for the possibility of targeting multiple genes in a single organism or the development of cocktails of PPMOs that target multiple pathogens. This project will identify lead target PPMOs in E. coli and A. baumannii that can be moved forward to pre- clinical and clinical studies.