Deciphering the role of Claudin-23 in regulation of the intestinal epithelial barrier

解读 Claudin-23 在肠上皮屏障调节中的作用

• 批准号: 10533889
• 负责人: Kristen Michelle Lozada-Soto
• 金额: $ 3.91万
• 依托单位: UNIVERSITY OF MICHIGAN AT ANN ARBOR
• 依托单位国家: 美国
• 财政年份: 2022
• 资助国家: 美国
• 起止时间: 2022-09-01 至 2024-09-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10533889
• 关键词: Actins; Active Sites; Antigens; Apical; Binding Sites; Biochemical; Biological Assay; Biopsy; Cell Line; Cell membrane; Cell physiology; Cellular biology; Chronic; Colon; Complement; Complex; Cytoskeleton; DNA Binding; Data; Development; Digestive System Disorders; Disease; Down-Regulation; Economic Burden; Environmental Risk Factor; Epithelial; Epithelial Cells; Etiology; Event; Family; Family member; Functional disorder; Gastrointestinal Diseases; Genetic Predisposition to Disease; Genetic Transcription; Goals; HIF1A gene; Health; Healthcare Systems; Homeostasis; Human; Hypoxia; Hypoxia Inducible Factor; Immune; In Vitro; Inflammation; Inflammatory; Inflammatory Bowel Diseases; Integral Membrane Protein; Intercellular Junctions; Intestines; Investigation; Knock-out; Knockout Mice; Knowledge; Lateral; Link; Membrane; Messenger RNA; Modeling; Molecular; Mucous Membrane; Mus; Nutrient; Oral; Pathologic; Patients; Permeability; Physicians; Physiological; Positioning Attribute; Property; Proteins; Quality of life; Reagent; Regulation; Role; Scaffolding Protein; Scientist; Signal Transduction; Spatial Distribution; Specificity; Stimulus; Techniques; Therapeutic Intervention; Tight Junctions; Tissues; Training; base; career; chromatin immunoprecipitation; colonic crypt; differential expression; disease mechanisms study; fluorescein isothiocyanate dextran; gastrointestinal symptom; gut homeostasis; in silico; in vivo; intestinal barrier; intestinal crypt; intestinal epithelium; knock-down; mRNA Expression; member; monolayer; murine colitis; normoxia; novel; novel therapeutic intervention; overexpression; promoter; protein expression; seal; tool; transcription factor; uptake; villin

PROJECT SUMMARY Intestinal epithelial cells (IECs) constitute a selective barrier that regulates nutrient uptake and restricts antigen access from the lumen to the underlying mucosa. Permeability across the intestinal epithelium is dynamically regulated by a range of physiologic and pathologic stimuli. Patients with chronic inflammatory bowel disease (IBD), suffer from debilitating gastrointestinal symptoms that significantly impact their quality of life and pose a disproportionately large economic burden on the healthcare system. Although genetic susceptibility, environmental factors, and immune dysregulation are all critical contributors to the multifactorial etiology of IBD, there is increasing evidence suggesting a central role for intestinal epithelial barrier dysfunction in IBD patients. Intestinal barrier properties are regulated through dynamic remodeling and maturation of intercellular junctions along the lateral membrane of IECs. Tight junctions (TJs) are the most apical intercellular junctional complex and are composed of a highly organized array of transmembrane proteins and cytoplasmic scaffolding proteins that anchor the complex to the actin cytoskeleton. The claudin (CLDN) family of TJ transmembrane proteins is comprised of 27 members in humans that control barrier function by regulating the sealing properties of the TJ. In the colon, CLDNs are differentially expressed to spatially regulate barrier properties. Notably, CLDN expression is perturbed in IBD and has been linked to barrier compromise. However, the mechanisms by which IECs differentially express CLDNs to control barrier function and how CLDN dysregulation contributes to epithelial barrier compromise in IBD remain unclear. In this proposal we present compelling preliminary data implicating CLDN23, an understudied non-classical claudin family member, as a central orchestrator of CLDN complex stability and TJ barrier function in IECs. Moreover, we have observed that CLDN23 expression is dysregulated in IBD. Thus, my proposed studies will employ novel tools to investigate how CLDN23 controls intestinal epithelial barrier function using complementary in vitro and in vivo techniques. Successful completion of the proposed studies will expand our knowledge of basic mechanisms that control intestinal epithelial barrier function in health and disease, and will open new avenues for investigation of therapeutic interventions to restore barrier properties and ameliorate inflammation in IBD. Importantly, this scientific proposal and training will position me for a sustained career as a physician-scientist studying the mechanisms of disease of gastrointestinal inflammatory illnesses.

项目概要 肠上皮细胞（IEC）构成了调节营养吸收和限制营养物质的选择性屏障。 抗原从管腔到达下面的粘膜。肠上皮的通透性为 受到一系列生理和病理刺激的动态调节。慢性肠道炎症患者 疾病（IBD），患有使人衰弱的胃肠道症状，严重影响他们的生活质量， 给医疗保健系统造成了不成比例的巨大经济负担。虽然有遗传易感性， 环境因素和免疫失调都是 IBD 多因素病因的关键因素， 越来越多的证据表明肠上皮屏障功能障碍在 IBD 患者中起着核心作用。 肠道屏障特性通过细胞间连接的动态重塑和成熟来调节 沿着 IEC 的侧膜。紧密连接（TJ）是最顶端的细胞间连接复合体 由高度组织化的跨膜蛋白和细胞质支架蛋白阵列组成 将复合物锚定到肌动蛋白细胞骨架上。 TJ 跨膜蛋白的紧密蛋白 (CLDN) 家族是 由人类的 27 个成员组成，通过调节 TJ 的密封特性来控制屏障功能。 在结肠中，CLDN 差异表达以空间调节屏障特性。值得注意的是，CLDN IBD 中的表达受到干扰，并且与屏障受损有关。然而，其机制 IEC 差异表达 CLDN 来控制屏障功能以及 CLDN 失调如何导致 IBD 中的上皮屏障受损仍不清楚。在本提案中，我们提供了令人信服的初步数据 暗示 CLDN23（一个未被研究的非经典 Claudin 家族成员）是 CLDN 的中央协调者 IEC 中的复杂稳定性和 TJ 屏障功能。此外，我们观察到 CLDN23 表达 IBD 失调。因此，我提出的研究将采用新颖的工具来研究 CLDN23 如何控制 使用互补的体外和体内技术研究肠上皮屏障功能。顺利完成 拟议的研究将扩大我们对控制肠上皮屏障的基本机制的了解 健康和疾病中的功能，并将为研究治疗干预措施以恢复健康开辟新途径 屏障特性并改善 IBD 炎症。重要的是，这种科学建议和培训将 使我能够作为一名研究疾病机制的医师科学家获得持续的职业生涯 胃肠道炎症性疾病。