Type 3 secretion system inhibitors to treat Pseudomonas aeruginosa keratitis

隐形眼镜相关性细菌性角膜炎是一种严重的眼部感染，如果治疗可能导致失明。 是没有效果的。最常见的是机会致病菌--铜绿假单胞菌 与隐形眼镜使用有关的病原体和多重耐药菌株的流行率正在上升。P. 铜绿假单胞菌在角膜上皮细胞上形成生物膜，导致对抗生素的抗药性增加，并导致死亡。 中性粒细胞，使这些感染的治疗进一步复杂化。大多数临床分离株来自这些感染 是表达ExoU的细胞毒性菌株，ExoU是一种通过3型分泌物注入宿主细胞的强大细胞毒素 系统(T3SS)，这与更高的毒力、抗生素耐药性和更高的发病率有关。 显然，治疗这些感染的新方法是必要的。铜绿假单胞菌的T3SS是一种毒力 对这种微生物在眼睛中建立感染至关重要的因素。这项提案的总体目标是 开发一种新的局部疗法来治疗隐形眼镜相关性角膜炎，靶向为P。 铜绿假单胞菌。在MicroBiotix(MBX)的一个正在进行的项目中，我们发现并对一种新的 苯氧乙酰胺(PHA)化学系列有效抑制铜绿假单胞菌T3SS，导致 具有优异的体外效力和ADM E性能的PHA的两性离子(ZW)模拟子系列。几个ZW 类似物在铜绿假单胞菌感染一致的非中性粒细胞减少的小鼠肺炎模型中有效 它们在体外试验和小鼠感染模型中的有效性。我们的小说发展战略 铜绿假单胞菌角膜炎的治疗是在体外评估一组精选的ZW PHA T3SS抑制剂 以及体内试验，旨在确定适合进一步开发作为局部附加物的主要候选者 铜绿假单胞菌角膜炎的抗菌药物治疗。在此第一阶段提案中，我们将优先考虑 ZW类似物文库的成员使用一组体外细胞为基础的T3SS抑制活性和细胞毒性 人角膜上皮细胞株的检测和角膜炎临床分离株。根据这些研究的结果 研究中，我们将确定多达6个类似物来评估对小鼠铜绿假单胞菌的耐受性和有效性。 角膜炎模型作为眼科抗生素的辅助治疗，目的是选择一个主要候选者 这适合在第二阶段的后续提案中进一步发展。第11阶段的研究将包括 眼科适应症的线索优化、眼科抗生素组合的评估、配方和 向FDA申请IND所需的临床前研究。 我们将通过完成以下具体目标来实现第一阶段的目标：目标1.确定选择PHA的优先顺序 T3SS抑制剂使用与眼部感染相关的体外检测。目标2.根据以下因素确定主要候选人 关于小鼠铜绿假单胞菌角膜炎模型的体内疗效。

Contact lens-associated bacterial keratitis is a serious infection of the eye that can result in blindness if treatment is not effective. The opportunistic Gram-negative pathogen Pseudomonas aeruginosa is the most common pathogen associated with contact lens use, and multi-drug resistant strains are increasing in prevalence. P. aeruginosa forms biofilms on the corneal epithelium, resulting in increased resistance to antibiotics and killing by neutrophils, further complicating the treatment of these infections. Most clinical isolates from these infections are cytotoxic strains that express ExoU, a potent cytotoxin that is injected into host cells by the type 3 secretion system (T3SS), which is associated with increased virulence, antibiotic resistance, and greater morbidity. Clearly, novel approaches to treating these infections are needed. The T3SS of P. aeruginosa is a virulence factor that is essential for this organism to establish infection in the eye. The overall goal of this proposal is to develop a novel topical therapy for the treatment of contact lens-associated keratitis that targets the T3SS of P. aeruginosa. In an ongoing program at Microbiotix (MBX), we discovered and chemically optimized a novel phenoxyacetamide (PhA) chemical series of potent inhibitors of the T3SS of P. aeruginosa, resulting in the zwitterionic (ZW) analog sub-series of PhAs with excellent in vitro potency and ADM E properties. Several ZW analogs were efficacious in a murine non-neutropenic pneumonia model with P. aeruginosa infection consistent with their efficacy in in vitro assays and in murine models of infection. Our strategy for developing novel treatments for P. aeruginosa keratitis is to evaluate a select set of these ZW PhA T3SS inhibitors using in vitro and in vivo assays designed to identify a lead candidate suitable for further development as a topical adjunctive therapy to anti-pseudomonal antibiotics for P. aeruginosa keratitis. In this Phase I proposal, we will prioritize members of a library of ZW analogs for T3SS inhibitory activity and cytotoxicity using a panel of in vitro cellbased assays and keratitis clinical isolates with human corneal epithelial cell lines. Based on the results of these studies, we will identify up to 6 analogs for evaluation of tolerability and efficacy in a murine P. aeruginosa keratitis model as an adjunctive therapy with an ophthalmic antibiotic, with the goal of selecting a lead candidate that is suitable for further development in a follow-on Phase II proposal. The Phase 11 research will comprise lead optimization for an ophthalmic indication, evaluation of ophthalmic antibiotic combinations, formulation, and pre-clinical studies that are required for an IND application to the FDA. We will accomplish the goals of Phase I by completing the following Specific Aims: Aim 1. Prioritize select PhA T3SS inhibitors using in vitro assays relevant to ophthalmic infection. Aim 2. Identify a lead candidate based on in vivo efficacy in a murine P. aeruginosa keratitis model.