Circumventing Antibiotic Resistance with Novel Gene-Silencing Therapeutics

描述（由申请人提供）：对新抗菌剂的需求日益迫切。耐多药病原体的比率继续增加，导致世界各地的发病率和死亡率显著上升。此外，目前新抗菌剂的管道仍然非常狭窄。美国传染病协会在他们的“坏虫子，没有药物”运动中发现了一组对当前抗生素越来越耐药的病原体。该组包括革兰氏阴性病原体鲍曼不动杆菌、铜绿假单胞菌和肺炎克雷伯菌。抗生素发现和设计的新范式最近已被证明对许多细菌有效。这种新方法基于一种称为肽-磷酰二胺吗啉代寡聚物（PPMO）的平台技术。PPMO是合成的DNA模拟物，其以序列特异性、反义方式结合RNA并抑制靶细菌基因的表达。PPMO已成功用于杀灭多种细菌病原体，包括革兰氏阴性细菌大肠杆菌、鼠伤寒沙门氏菌、洋葱伯克霍尔德氏菌复合体和鲍氏不动杆菌。PMOS在培养物中是杀菌的，并且在感染的动物模型中减少菌血症和提高存活率。PPMO比许多传统抗生素（如氨苄青霉素）更有效。本项目的目标是开发PPMO用于治疗多重耐药病原体鲍曼不动杆菌、铜绿假单胞菌和肺炎克雷伯菌。具体目标是设计、生产和筛选针对这些多重耐药病原体中各种基因靶标的PPMOS。实验方法将针对不动杆菌和假单胞菌的毒力特性，以及克雷伯氏菌的必需或抗生素抗性基因。在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。这项技术提供了一个方法上的优势，因为许多PMOs可以快速合成，并同时测试对许多目标。这使得靶向单一生物体中的多个基因或开发靶向多种病原体的PPMO鸡尾酒成为可能。本项目将确定这些具有医学重要性的革兰氏阴性病原体中的主要靶点PPMO，这些病原体可用于临床前和临床研究。

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.