Tissue remodeling in Eosinophilic Esophagitis: Discovery of novel pathways

项目总结 这个R03项目直接来自Menard-Katcher博士的K23奖中描述的研究。建议数 AIMS在Menard-Katcher博士更广泛的职业生涯目标中定义了新的研究方向 将提供基本数据、关键技能和重要协作的开发。把这些意志放在一起 为R01应用提供平台，完全自主研究。 嗜酸性食管炎(EoE)是一种慢性过敏原介导的炎症性食管病，具有 对儿童和成人造成了巨大的和不断增加的负担。慢性炎症通常会导致吞咽困难。 越来越多的证据表明，一部分患者会发展为临床上有意义的纤维化和食道 狭窄，一种被认为具有更严重的症状和更差的治疗反应的表型。被称为 纤维狭窄性EoE(FS-EoE)，此表型可通过部分闭塞性狭窄形成来定义。识别 那些有最大纤维化风险的患者；确定最佳处理策略；以及弥合我们 对纤维化疾病发展过程中涉及的细胞通路的了解都是有帮助的 提供量身定制的治疗方法。在Menard-Katcher博士的K23支持下，我们评估和表征了 110多名儿童EoE患者的临床结果、症状、内窥镜表现、组织学和 食道功能(即膨胀性)。从这些患者的子集进行的RNAseq分析确定了与 可定义FS-EoE表型的改变的表达。基因通路分析鉴定SMAD蛋白 纤维性(有狭窄)和非纤维性之间差异表达的磷酸化途径 (无狭窄)EoE受试者与特异性结缔组织生长因子(CTGF/CCN2) FS-EoE表型过表达。 CTGF(或CCN2)是一种分泌的调节性基质细胞蛋白，通常参与促进纤维化 通过转化生长因子/SMAD对损伤作出反应。CTGF与肾脏纤维化的进展有关， 肺和皮肤，它可能是一个顺从的治疗目标。我们假设CTGF参与了促进 EoE的纤维化重塑和对EoE蛋白质组的评估将识别与 更严重的纤维化表型。为了解决这一总体假设，我们提出了两个相关的但 独立的目标。由于CTGF尚未在EoE或食道中被探索，在目标1中，我们将确定 结缔组织生长因子在EoE体内和体外的表达。在目标2中，我们将评估食道 黏膜蛋白质组以确定与纤维狭窄表型有关的靶点和途径。 拟议的AIMS的结果将阐明CTGF途径是否与EoE有关，并使用多个 组学数据为下一步发病机制和可能的研究确定新的途径和靶点 FS-EoE的治疗。这将提供新的证据来支持成功的R01或类似的应用程序 将研究疾病的生物机制和治疗FS-EoE的创新方法。

PROJECT SUMMARY This R03 project emerges directly from studies described in Dr. Menard-Katcher’s K23 award. The proposed aims define a new direction of investigation within the broader goals of Dr. Menard-Katcher’s career development that will provide essential data, critical skills and important collaborations. Together these will provide a platform for R01 applications and complete research independence. Eosinophilic Esophagitis (EoE) is a chronic allergen mediated inflammatory esophageal disease with substantial and increasing burden in children and adults. Chronic inflammation classically leads to dysphagia. Mounting evidence identifies a subset of patients who develop clinically significant fibrosis and esophageal stricture, a phenotype identified to have more severe symptoms and worse treatment response. Termed fibrostenotic EoE (FS-EoE), this phenotype can be defined by partially occlusive stricture formation. Identifying those patients at greatest risk of fibrosis; determining optimal management strategies; and closing gaps in our understanding of the cellular pathways involved in the development of fibrotic disease are all needed to help provide tailored approach to therapy. Supported by Dr. Menard-Katcher’s K23, we evaluated and characterized over 110 pediatric EoE patients based on clinical outcomes, symptoms, endoscopic appearance, histology and esophageal function (ie distensibility). RNASeq analysis from a subset of these patients identified genes with altered expression that could define a FS-EoE phenotype. Gene pathway analysis identified SMAD protein phosphorylation pathways to be differentially expressed between fibrotic (with stricture) and non-fibrotic (without stricture) EoE subjects and specifically identified connective tissue growth factor (CTGF/CCN2) overexpression in the FS-EoE phenotype. CTGF (or CCN2) is a secreted regulatory matricellular protein involved in promoting fibrosis often through TGFß /SMAD in response to injury. CTGF is implicated in the progression of fibrosis in the kidney, lung and skin and it may be an amenable target for treatment. We hypothesize CTGF is involved in promoting fibrotic remodeling in EoE and that evaluation of the EoE proteome will identify novel proteins implicated in a more severe fibrotic phenotype. To address this overarching hypothesis, we propose two related but independent aims. As CTGF has not yet been explored in EoE or the esophagus, in Aim 1 we will determine CTGF expression in in vitro and in a novel in vivo model of EoE. In Aim 2 we will evaluate the esophageal mucosal proteome to identify targets and pathways implicated in the fibrostenotic phenotype. Results from the proposed Aims will elucidate if the CTGF pathway is implicated in EoE and use multi- omic data to identify novel pathways and targets for next step research in the pathogenesis and possible treatment of FS-EoE. This will provide novel evidence to support a successful R01 or similar application that will investigate biomechanisms of disease and innovative approaches to management of FS-EoE.