Innovative Therapeutic Targets for Fungal Keratitis

描述（由申请人提供）：我们报告了真菌抗氧化途径和铁结合分子（铁载体）对于哺乳动物角膜中的菌丝生长至关重要（J Clin Invest 2012，PMC 3708856; PLoS Pathogens 2013，PMC 3534057）。我们还证明，这些途径可以使用抗癌药物PX-12（抑制硫氧还蛋白途径）和辛伐他汀（抑制曲霉铁载体TAFC的产生）靶向（9，10）。在目前的建议中，我们还显示了初步的数据，抑制锌转运损害曲霉菌丝在体外的生长。目前提案中概述的研究将检查PX-12，他汀类药物与其他靶向这些途径的药物的比较，这些药物要么在常规临床使用中，要么已经通过I期试验并显示无毒（所有都是市售的）。然后，我们将使用多靶点方法将最有效的化合物联合收割机组合。在第1年，我们将在直接体外菌丝杀灭试验（目的1）、旨在增强人中性粒细胞对菌丝杀灭的体外试验（目的2）以及我们建立的创伤诱导和接触透镜/生物膜诱导的真菌性角膜炎小鼠模型（目的3）中确定最有效的药物。在第二年，我们将完成目标3，并基于鼠模型中的发现，我们将在接触透镜相关真菌性角膜炎的新兔模型中检查疗效。两性霉素B或纳他霉素作为真菌性角膜炎的常用疗法也将包括在内，我们将检查每种药物及其组合的细胞毒性。这些新方法靶向角膜中菌丝生长的基本途径，由于它们局部给药，没有预期的全身副作用，并且作为这种重要疾病的新疗法具有相当大的潜力。

DESCRIPTION (provided by applicant): We reported that fungal anti-oxidant pathways and iron binding molecules (siderophores) are essential for hyphal growth in the mammalian cornea (J Clin Invest 2012, PMC3708856; PLoS Pathogens 2013, PMC3534057). We also demonstrated that these pathways can be targeted using the anti-cancer drug PX-12, which inhibits the thioredoxin pathway, and by Simvastatin, which inhibits production of the Aspergillus siderophore TAFC (9, 10). In the current proposal, we also show preliminary data that inhibition of zinc transport impairs growth of Aspergillus hyphae in vitro. Studies outlined in the current proposal will examine PX-12, statins compared with other drugs that target these pathways, and which are either in routine clinical use, or which have gone through Phase I trials and shown to be non-toxic (all are commercially available). We will then combine the most effective compounds using a multi-target approach. In year 1, we will determine the most effective agents in a direct in vitro hyphal killing assay (Aim 1), in an in vitro assay designed to augment hyphal killing by human neutrophils (Aim 2), and in our established murine models of trauma induced and contact lens/biofilm induced fungal keratitis (Aim 3). In the second year, we will complete Aim 3 and based on findings in the murine models, we will examine efficacy in a new rabbit model of contact lens associated fungal keratitis. Amphotericin B or natamycin, as common therapies for fungal keratitis, will also be included, and we will examine cytotoxicity of each dru and combination. These novel approaches target essential pathways of hyphal growth in the cornea, have no anticipated systemic side effects as they are administered topically, and have considerable potential as novel therapies for this important disease.