The Role of Lysyl Oxidase in Epithelial Differentiation in Eosinophilic Esophagitis

项目摘要 这一R 03提案直接源于Muir博士的 K08该奖项代表了一个新的研究方向，将促进缪尔博士的进步， 独立该奖项将使缪尔博士获得额外的技能，在结合基因改变的细胞， 三维培养系统，以确定食管上皮分化的新机制 与嗜酸性粒细胞性食管炎（EoE）直接相关。这将在研究的指导下实现 导师，Rustgi博士和Nakagawa博士以及我的K 08跨学科咨询委员会Herlyn博士（主席）， Tong和Heuckeroth。 嗜酸性粒细胞性食管炎（EoE）是一种过敏性疾病，其特征是食管浸润， 嗜酸性粒细胞除了炎性细胞浸润外，这种疾病的组织学特征是上皮细胞浸润， 变化，特别是上皮分化失败导致基底细胞增生。在体内平衡状态下 在某些条件下，已知食管上皮分化受Notch受体家族调节， 然而，关于EoE背景下Notch调节的了解很少。通过正在进行的K 08的工作，博士。 Muir研究了胶原交联酶赖氨酰氧化酶（LOX）在EoE中促进纤维化的作用。 在这项提案中提出的工作中，她现在试图确定这种酶对食管癌的影响。 上皮分化缪尔博士的初步数据表明LOX会影响上皮细胞的增殖 食管中的分化梯度。在LOX过表达的食管上皮细胞（EPC-LOX）中， 是在3D类器官培养中上皮分化的丧失，并且Notch信号传导被抑制。基于这些 研究发现，总体假设是LOX介导的Notch信号抑制有助于EoE 通过限制鳞状细胞分化和促进屏障缺陷来抑制病理生物学。以强为导 初步数据，这一假设将通过追求两个具体目标进行测试：1）确定关系 LOX和EoE相关的上皮分化和完整性损伤之间的关系，以及2）确定LOX和EoE如何影响上皮分化和完整性。 LOX介导的Notch信号调节影响鳞状细胞分化在第一个目标下，她将 评估LOX过表达对增殖分化和屏障完整性的影响， 细胞增殖和屏障完整性的测定。在第二个目标中，她将定义Notch信号如何 在LOX过表达的情况下，有助于受损的鳞状分化。在这方面， 该提案是创新的，因为它利用了一种新的食管3D类器官培养系统， 在体内观察食管组织学和上皮分化。这项研究具有重要意义，因为 目的阐明LOX在食管上皮分化中的作用，为今后的研究提供基础 在EoE管理中的翻译应用。

PROJECT SUMMARY This R03 proposal stems directly from studies and career development activities outlined in Dr. Muir’s K08. This award represents a new research direction that will enhance Dr. Muir’s advancement towards independence. This award will allow Dr. Muir to obtain additional skills in combining genetically altered cells with three-dimensional culture systems in order to define novel mechanisms of esophageal epithelial differentiation with direct relevance to eosinophilic esophagitis (EoE). This will be achieved with the guidance of research mentors, Drs. Rustgi and Nakagawa and my K08 interdisciplinary advisory committee of Drs. Herlyn (Chair), Tong, and Heuckeroth. Eosinophilic esophagitis (EoE) is an allergic disease characterized by esophageal infiltration of eosinophils. In addition to inflammatory cell invasion, this disease is characterized histologically by epithelial changes, specifically failure of epithelial differentiation leading to basal cell hyperplasia. Under homeostatic conditions, esophageal epithelial differentiation is known to be regulated by the Notch family of receptors, however, little is known about Notch regulation in the context of EoE. Through the work of the ongoing K08, Dr. Muir has investigated the role of collagen cross linking enzyme, lysyl oxidase (LOX) in promoting fibrosis in EoE. In the work presented in this proposal, she now seeks to determine the effects of this enzyme on esophageal epithelial differentiation. Dr. Muir’s preliminary data demonstrate that LOX affects the epithelial proliferation- differentiation gradient in the esophagus. In LOX over-expressing esophageal epithelial cells (EPC-LOX) there is loss of epithelial differentiation in 3D organoid culture and Notch signaling is suppressed. Based on these findings the overall hypothesis is that LOX-mediated suppression of Notch signaling contributes to EoE pathobiology by limiting squamous differentiation and promoting barrier defects. Guided by strong preliminary data, this hypothesis will be tested by pursuing two specific aims: 1) Determine the relationship between LOX and EoE-associated impairment of epithelial differentiation and integrity and 2) Determine the how LOX-mediated modulation of Notch signaling influences squamous differentiation. Under the first aim, she will evaluate the effects of LOX overexpression on proliferation-differentiation and barrier integrity utilizing functional assays of cell proliferation and barrier integrity. In the second aim, she will define how Notch signaling contributes to impaired squamous differentiation in the context of LOX over-expression. The approach in this proposal is innovative because it utilizes a novel esophageal 3D organoid culture system which recapitulates esophageal histology and epithelial differentiation observed in vivo. The proposed research is significant as it seeks to elucidate the role of LOX in esophageal epithelial differentiation and provide the basis for future studies with translational applications in the management of EoE.