Mechanisms of extrahepatic biliary proliferation and regeneration

肝外胆管增殖和再生的机制

• 批准号: 9806419
• 负责人: Nataliya Razumilava
• 金额: $ 16.89万
• 依托单位: UNIVERSITY OF MICHIGAN AT ANN ARBOR
• 依托单位国家: 美国
• 财政年份: 2019
• 资助国家: 美国
• 起止时间: 2019-08-15 至 2024-05-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9806419
• 关键词: Address; Affect; Attenuated; Biliary; Binding; Biology; CD44 gene; Cell Communication; Cell Proliferation; Cells; Cholangiocarcinoma; Coculture Techniques; Data; Development; Disease; Epithelial; Epithelial Cells; Epithelium; Erinaceidae; Extrahepatic; Extrahepatic Bile Ducts; Fibroblasts; Flow Cytometry; Funding; GLI gene; GLI2 gene; GLI3 gene; Genes; Genetic; Genetic Transcription; Glioma; Goals; Health; Hepatobiliary; Homeostasis; Human; Immunohistochemistry; In Situ Hybridization; In Vitro; Injury; Ligands; Ligation; Mediator of activation protein; Mesenchymal; Mission; Modeling; Molecular; Mus; Natural regeneration; Organoids; Pathway interactions; Patients; Pharmacological Treatment; Pharmacology; Play; Population; Production; Public Health; Quality of life; Regenerative Medicine; Reporter; Research; Research Personnel; Role; Signal Pathway; Signal Transduction; Source; Stromal Cells; System; Techniques; Testing; Transgenic Mice; Transgenic Organisms; United States National Institutes of Health; WNT Signaling Pathway; base; beta catenin; bile duct; cholangiocyte; effective therapy; improved outcome; in vivo; inhibitor/antagonist; liver transplantation; loss of function; mouse model; novel; novel therapeutics; programs; receptor; response; response to injury; skills; smoothened signaling pathway; therapy development; tool; translational study

PROJECT SUMMARY/ABSTRACT Cholangiopathies are incurable, progressive extrahepatic bile duct (EHBD) disorders characterized by injury- induced cholangiocyte hyperproliferation. Development of therapies for cholangiopathies requires better understanding of cellular and molecular mechanisms regulating EHBD proliferation during homeostasis and in response to injury. Molecular pathways that regulate cholangiocyte proliferation are currently not well understood. This application aims to answer a fundamental question about mechanisms of EHBD regeneration and explore strategies to modulate the proliferative potential of the biliary epithelium. The rationale for the proposed research is that defining cellular and molecular interactions underlying cholangiocyte responses to injury can offer novel therapeutic strategies for cholangiopathies and hepatobiliary regenerative medicine. Our preliminary data suggest that Hedgehog (HH) and WNT signaling play important roles in EHBD homeostasis and proliferation after injury. The overarching hypothesis for this proposal is that HH and WNT signaling regulate crosstalk between epithelial and stromal cells to promote EHBD proliferation after injury. In this proposal, we will use genetic mouse models and pharmacological treatments in vivo. Bile duct ligation will be used as an injury model. Human and mouse EHBD organoid (BDO) co-culture with primary mesenchymal cells will be used to directly study epithelial-stromal crosstalk and pathway interaction in vitro and enhance the translational component of this project. Aim 1 will focus on HH signaling and determine if the Indian HH ligand from cholangiocytes signals to GLI1+ HH-responsive fibroblasts to indirectly regulate cholangiocyte proliferation. Aim 2 will focus on WNT signaling and test if WNT from GLI1-expresing cells is critical for cholangiocyte proliferation. Aim 3 will focus on cell-cell and pathway interactions and determine if IHH from cholangiocytes directly regulates WNT production by fibroblasts to induce cholangiocyte proliferation. Under Aims 1 and 2 we will use transgenic reporter and loss-of-function mouse models, pharmacological inhibitors of HH and WNT signaling, in situ hybridization, and immunohistochemistry techniques to define the in vivo effects. Under Aim 3 we take a reductionist approach by using organoid co-culture models. It will also support the development of robust new tools (transgenic mice and organoid models) and skills (in situ hybridization and flow cytometry) to support an independent research program focused on fundamental signaling pathways regulating EHBD. This new K08 application will also promote the development of the PI into an independent NIH-funded investigator and support her long-term goal to understand fundamental mechanisms of EHBD biology to ultimately improve outcomes in patients with cholangiopathies.

项目摘要/摘要 胆管病是无法治愈的，进行性肝外胆管（EHBD）疾病，其特征是以损伤为特征 诱导的胆管细胞过增殖。开发胆管疾病的疗法需要更好 了解调节稳态期间EHBD增殖的细胞和分子机制 对伤害的反应。当前调节胆管细胞增殖的分子途径目前不好 理解。该应用程序旨在回答有关EHBD再生机制的基本问题 并探讨调节胆道上皮的增殖潜力的策略。理由 拟议的研究是，定义了胆管细胞反应的细胞和分子相互作用对 损伤可以为胆管疾病和肝胆再生医学提供新颖的治疗策略。我们的 初步数据表明，刺猬（HH）和Wnt信号在EHBD稳态中起重要作用 和受伤后的扩散。该提议的总体假设是HH和Wnt信号传导 调节上皮细胞和基质细胞之间的串扰，以促进损伤后的EHBD增殖。在 该提议将在体内使用遗传小鼠模型和药理治疗。胆管连接将 用作伤害模型。人和小鼠EHBD器官（BDO）与主要间质培养 细胞将用于直接研究上皮 - 核串扰和体外途径相互作用，并增强 该项目的翻译组成部分。 AIM 1将重点放在HH信号上，并确定印度HH配体是否是否 从胆管细胞信号到GLI1+ HH响应性成纤维细胞，到间接调节胆管细胞 增殖。 AIM 2将重点放在Wnt信号传导上，并测试是否来自Gli1的WNT是否对 胆管细胞增殖。 AIM 3将专注于细胞电池和途径相互作用，并确定IHH是否来自 胆管细胞直接通过成纤维细胞调节WNT产生，以诱导胆管细胞增殖。在下面 目标1和2我们将使用转基因报告基因和功能丧失的小鼠模型，药理抑制剂 HH和WNT信号传导，原位杂交和免疫组织化学技术来定义体内 效果。在AIM 3下，我们通过使用器官共培养模型采用还原主义方法。它也将支持 强大的新工具（转基因小鼠和器官模型）和技能的开发（原位杂交 和流式细胞仪）以支持针对基本信号通路的独立研究计划 调节EHBD。该新的K08应用程序还将促进PI的开发成独立 NIH资助的研究人员并支持她的长期目标，以了解EHBD的基本机制 生物学最终改善胆管疾病患者的结局。