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Novel Combination Therapies to Combat Hypermutable Carbapenem-Resistant P. aeruginosa

对抗高突变碳青霉烯类耐药铜绿假单胞菌的新型联合疗法

基本信息

批准号：
10522530
负责人：
MARK D. SUTTON
金额：
$ 80.51万
依托单位：
STATE UNIVERSITY OF NEW YORK AT BUFFALO
依托单位国家：
美国
项目类别：
财政年份：
2022
资助国家：
美国
起止时间：
2022-05-24 至 2027-04-30
项目状态：
未结题

来源：
https://reporter.nih.gov/project-details/10522530
关键词：
Animal Model Antibiotic Resistance Antibiotics Antimicrobial Resistance Antineoplastic Agents Attention Aztreonam Bacteria Bacterial Infections Biochemistry Bypass Ceftazidime Cell division Cells Chemistry Clinical Trials Collection Combined Antibiotics Combined Modality Therapy Communities DNA DNA Damage DNA Repair DNA Replication Damage DNA biosynthesis DNA lesion DNA-Directed DNA Polymerase Data Development Discipline Excision Exposure to Fiber Filament Frequencies Future Genetic Genomics Goals Guanine Health Human In Vitro Location Maintenance Medical Mismatch Repair Mobile Genetic Elements Modernization Monobactams Mutagenesis Mutation Nucleosides Nucleotides Oxides Pathway interactions Patients Penicillin-Binding Proteins Pharmaceutical Preparations Pharmacology Phenotype Polymerase Process Pseudomonas aeruginosa Pseudomonas aeruginosa infection Public Health Regimen Replication Error Research Resistance Role SOS Response Septate System Testing Time Treatment Failure Treatment Protocols United States antimicrobial tolerance arm beta-Lactamase beta-Lactams cancer therapy carbapenem resistance combat combinatorial defined contribution genome integrity in vivo inhibitor insight mortality novel novel therapeutic intervention novel therapeutics pathogen pressure prevent repair function repaired resistance mechanism resistant strain small molecule standard of care stem targeted agent therapeutic target treatment strategy

项目摘要

ABSTRACT: Carbapenem-resistant Pseudomonas aeruginosa (CRPA) poses an urgent threat to human health in the United States and globally. Metallo-β-lactamases (MBL), which confer high-level carbapenem resistance, warrant significant attention. The paucity of treatment options for CRPA MBL-producing Pseudomonas aeruginosa (MBL PA) and the broken antibiotic pipeline demands the development of new therapeutic strategies that target non-traditional, unexploited pathways. There is mounting evidence that ‘hypermutator’ strains, which show a significantly increased spontaneous mutation frequency (10-fold higher than non-mutator control), serve as the basis for pathoadaptation and antimicrobial tolerance, inevitably increasing the likelihood of treatment failure and bacterial persistence in PA infections. Importantly, errors made during DNA replication and translesion DNA synthesis (TLS Pol IV) serve as the mechanistic basis for mutations in PA hypermutator strains. We have pioneered the synthesis and testing of novel non-natural nucleotides as remarkably safe and effective anti-cancer therapies, which is supported by our preliminary data. For the first time, we now propose to study non-natural nucleotides by defining the underlying mechanism of hypermutators in pathoadaptation, persistence and antimicrobial resistance and develop combination regimens to combat MBL PA. Our overarching goal is to develop new combinatorial treatment strategies for MBL PA using novel anti-mutator non-natural nucleotides together with available β-lactam antibiotics. One promising bridge therapy for MBL Gram-negatives is ceftazidime-avibactam combined with aztreonam; however, this strategy has not been studied in MBL PA. In preliminary studies, we observed long filamentous persisters due to inhibition of penicillin binding protein 3 in MBL PA exposed to the ceftazidime-avibactam and aztreonam combination. Since the SOS response to DNA damage is required for filamentation, while TLS DNA polymerases (Pols) are required to bypass DNA lesions generated in persister cell DNA leading to antimicrobial resistance, we hypothesize that in the absence of repair functions, the ability of persisters to cope with DNA damage and subsequently septate and grow becomes increasingly dependent on TLS Pol IV. Given this critically important role of PA Pol IV, our overarching hypothesis that novel, non-natural nucleotides that target Pol IV to block replication of damaged DNA will be highly effective together with existing β-lactam antibiotics. To test these hypotheses, we will: (Aim 1) define the contributions of hypermutators to resistance and persistence of MBL PA exposed to β-lactam combinations; (Aim 2) develop small molecule, non-natural nucleotides targeting TLS Pol IV to combat mutation in MBL PA; (Aim 3) define optimal combinatorial treatment regimens of non-natural nucleosides and β-lactams that suppresses resistance, and prevents persistence of MBL PA in hollow fiber and animal models. Taken together, our results will provide unprecedented insight into novel combination therapies for Gram-negatives, and will set the cornerstone for future testing of anti-mutator non-natural nucleotides in clinical trials.

摘要：耐碳青霉烯类铜绿假单胞菌（CRPA）对人类健康构成紧迫威胁在美国和全球范围内。金属-β-内酰胺酶（MBL），赋予高水平的碳青霉烯类耐药性，值得高度关注。产生 CRPA MBL 的假单胞菌的治疗选择匮乏铜绿假单胞菌 (MBL PA) 和破碎的抗生素管道需要开发新的治疗策略针对非传统的、未开发的途径。越来越多的证据表明“超突变”菌株，显示出显着增加的自发突变频率（比非突变对照高 10 倍），作为路径适应和抗菌药物耐受性的基础，不可避免地增加治疗的可能性 PA 感染的失败和细菌持续存在。重要的是，DNA复制过程中发生的错误和跨损伤 DNA 合成 (TLS Pol IV) 是 PA 超突变株突变的机制基础。我们率先合成和测试新型非天然核苷酸，因为它们非常安全有效抗癌疗法，这是有我们初步数据支持的。我们现在第一次提出研究通过定义超突变子在路径适应、持久性中的潜在机制来研究非天然核苷酸和抗菌素耐药性，并开发联合方案来对抗 MBL PA。我们的总体目标是使用新型抗突变非天然核苷酸开发新的 MBL PA 组合治疗策略与可用的β-内酰胺抗生素一起使用。一种有前景的针对 MBL 革兰氏阴性菌的过渡疗法是头孢他啶-阿维巴坦联合氨曲南；然而，该策略尚未在 MBL PA 中进行研究。在初步研究中，我们观察到由于青霉素结合蛋白 3 的抑制而导致的长丝状持续存在 MBL PA 暴露于头孢他啶-阿维巴坦和氨曲南组合。由于对 DNA 的 SOS 反应丝状形成需要损伤，而 TLS DNA 聚合酶 (Pols) 需要绕过 DNA 损伤在持久细胞 DNA 中产生，导致抗菌药物耐药性，我们假设在没有修复的情况下功能，持久者应对 DNA 损伤并随后分隔和生长的能力变得越来越依赖 TLS Pol IV。鉴于 PA Pol IV 的这一至关重要的作用，我们的首要任务假设靶向 Pol IV 的新型非天然核苷酸将阻止受损 DNA 的复制与现有的β-内酰胺类抗生素配合使用非常有效。为了检验这些假设，我们将：（目标 1）定义超变子对暴露于 β-内酰胺组合的 MBL PA 的耐药性和持久性的贡献；（目标 2）开发针对 TLS Pol IV 的小分子非天然核苷酸以对抗 MBL PA 突变；（目标 3）定义非天然核苷和 β-内酰胺的最佳组合治疗方案，抑制耐药性，并防止 MBL PA 在中空纤维和动物模型中持续存在。综合起来，我们的结果将为革兰氏阴性菌的新型联合疗法提供前所未有的见解，并将设定未来在临床试验中测试抗突变非天然核苷酸的基石。