Circumventing Antibiotic Resistance with Novel Gene-Silencing Therapeutics

描述(申请人提供)：对新的抗菌剂的需求日益迫切。耐多药病原体的比率继续上升，导致全世界的严重发病率和死亡率。此外，目前新抗菌剂的流水线仍然非常狭窄。美国传染病学会在他们的“Bad Bugs，No Druits”运动中发现了一组病原体，它们对目前的抗生素越来越耐药。其中包括革兰氏阴性杆菌鲍曼不动杆菌、铜绿假单胞菌和肺炎克雷伯菌。最近，抗生素发现和设计中的一种新范式被证明对许多细菌有效。这一新方法是基于一种名为多肽-磷二酸酯莫霍利诺齐聚物(PPMOS)的平台技术。PPMO是一种人工合成的DNA模拟物，以序列特异性的反义方式与RNA结合，抑制目标细菌基因的表达。PPMO已经成功地用于杀死各种细菌病原体，包括革兰氏阴性杆菌、大肠杆菌、鼠伤寒沙门氏菌、洋葱伯克霍尔德氏菌复合体和鲍曼不动杆菌。PPMO在培养中具有杀菌作用，在感染动物模型中可以减少菌血症并提高存活率。PPMO比氨苄西林等许多传统抗生素更有效。该项目的目标是开发用于治疗鲍曼不动杆菌、铜绿假单胞菌和肺炎克雷伯菌的PPMO。其具体目标是设计、生产和筛选针对这些多重耐药病原体中不同基因靶点的PPMO。实验方法将针对不动杆菌和假单胞菌的毒力特性，以及克雷伯氏菌的基本或抗生素耐药性基因。在我们的筛选阶段有效的先导化合物将在动物感染模型中进行有效性测试。这项技术提供了方法学上的优势，因为许多PPMO可以快速合成，并同时针对许多目标进行测试。这使得有可能针对单个生物体中的多个基因，或者开发针对多种病原体的PPMO鸡尾酒。该项目将确定这些医学上重要的革兰氏阴性病原体中的主要靶标PPMO，这些病原体可以推进到临床前和临床研究。

DESCRIPTION (provided by applicant): 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, Pseudomonas aeruginosa and Klebsiella pneumoniae. 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 target 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 Acinetobacter baumannii, Pseudomonas aeruginosa and Klebsiella pneumoniae. The specific aims are to design, produce and screen PPMOS against various gene targets in these multidrug-resistant pathogens. The experimental approach will be to target virulence properties in Acinetobacter and Pseudomonas, and essential or antibiotic resistance genes in Klebsiella. Lead compounds that are effective during our screening phase will then be tested for efficacy in animal models of infection. 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 these medically important Gram- negative pathogens that can be moved forward to pre-clinical and clinical studies.