Innovative Therapeutic Targets for Fungal Keratitis

描述（由申请人提供）：我们报道了真菌抗氧化途径和铁结合分子（铁载体）对哺乳动物角膜菌丝生长至关重要（J clinin Invest 2012, PMC3708856; PLoS Pathogens 2013, PMC3534057）。我们还证明，可以使用抗癌药物PX-12和辛伐他汀靶向这些途径，它们可以抑制硫氧还蛋白途径，辛伐他汀可以抑制siderophore曲霉TAFC的产生（9,10）。在目前的提案中，我们也显示了初步数据，抑制锌的运输损害了体外曲霉菌丝的生长。当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，要么已经通过I期试验并显示无毒（所有这些都是市售的）。然后，我们将使用多靶点方法组合最有效的化合物。在第一年，我们将在直接体外菌丝杀灭试验（Aim 1）中确定最有效的药物，在体外试验中设计增强人类中性粒细胞的菌丝杀灭（Aim 2），以及在我们建立的创伤诱导和接触镜/生物膜诱导的真菌角膜炎小鼠模型中（Aim 3）。在第二年，我们将完成Aim 3，并基于小鼠模型的发现，我们将在新的兔模型中检测隐形眼镜相关性真菌性角膜炎的疗效。两性霉素B或纳他霉素，作为真菌角膜炎的常用治疗方法，也将包括在内，我们将检查每种药物和组合的细胞毒性。这些新方法针对角膜菌丝生长的基本途径，由于它们是局部施用，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.