CFTR modulates innate immune response in biliary epithelium: Role in the pathogenesis and treatment of Cystic-Fibrosis-related liver disease.

CFTR 调节胆管上皮的先天免疫反应：在囊性纤维化相关肝病的发病机制和治疗中的作用。

• 批准号: 9982301
• 负责人: Mario Strazzabosco
• 金额: $ 56.09万
• 依托单位: YALE UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2013
• 资助国家: 美国
• 起止时间: 2013-05-01 至 2023-07-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9982301
• 关键词: Affect; Bicarbonates; Bile Acids; Bile fluid; Biliary; Biliary cirrhosis; Biochemical; Birth; Cells; Chlorides; Chronic; Clinical; Cystic Fibrosis; Cystic Fibrosis Transmembrane Conductance Regulator; DNA Sequence Alteration; Data; Delta F508 mutation; Development; Duct (organ) structure; Endotoxemia; Endotoxins; Epithelial; Epithelial Physiology; Epithelium; Event; Exposure to; Family; Fluids and Secretions; Foundations; Funding; Genetic; Genetic Diseases; Hepatobiliary; Human; Impairment; In Vitro; Inflammation; Inflammatory; Inflammatory Response; Innate Immune Response; Innate Immune System; Intervention; Intestinal permeability; Intestines; Knockout Mice; Knowledge; Ligands; Liver; Liver diseases; Mediating; Membrane Proteins; Modeling; Mus; Mutation; Natural Immunity; Noxae; Outcome; PTPRC gene; Pathogenesis; Patients; Phenotype; Phosphotransferases; Play; Prevalence; Production; Quality of life; Regulation; Role; Sclerosing Cholangitis; Signal Transduction; TLR4 gene; Testing; acquired factor; apical membrane; base; bile duct; biliary tract; cholangiocyte; clinically significant; cystic fibrosis mouse; cystic fibrosis patients; cytokine; dextran sulfate sodium induced colitis; disease-causing mutation; experimental study; gut microbiota; improved; induced pluripotent stem cell; innate immune mechanisms; liver cystic fibrosis; liver development; liver transplantation; macrophage; microbiota; novel; response; src-Family Kinases; stem cell technology; treatment strategy

SUMMARY Cystic Fibrosis (CF) is a common and clinically severe genetic disease, caused by mutations in CFTR, a membrane protein that mediates chloride and fluid secretion in a number of secretory epithelia, including the biliary tree. Cystic Fibrosis liver disease (CFLD) is a chronic cholangiopathy that can eventually evolve into sclerosing cholangitis and focal biliary cirrhosis. The pathogenesis of this condition is not well understood and treatment is limited to the administration of choleretic bile acids, or in selected cases, liver transplantation. CFLD has been classically considered a consequence of the impaired bile secretion caused by the defective CFTR channel function. However, while biliary secretion is universally reduced in CF, the spontaneous development of CFLD is less frequent, suggesting that genetic and/or acquired factors are at play. Our previous studies suggested that reduced tolerance of the biliary innate immune system to endotoxins plays a major pathogenetic role in CFLD. We showed that cholangiocytes isolated from Cftr-KO mice have higher NF-κB activity and secrete a larger amount of inflammatory cytokines, when exposed to the TLR4-ligand LPS. We have also demonstrated that in CF-defective cholangiocytes, TLR4 is activated by the unrestrained function of Src family kinases (SFK), a consequence of defective CFTR. This mechanism is present also in cholangiocytes derived from human iPSC homozygous for the ΔF508 mutation. In addition, novel exciting preliminary data show that the gut microbiota in CFTR-KO mice is already different from WT littermates at birth and it is skewed towards the prevalence of a more pro-inflammatory flora. In this application we will test the hypothesis that CFLD may result from the combination of a genetic mutation affecting biliary epithelial innate immunity along with changes in microbiota composition and increased intestinal permeability. In particular, (1) we will use iPSC technology to dissect the impact of functionally different CFTR mutations on the mechanisms leading to a pro-inflammatory phenotype in human cholangiocytes and (2) we will study whether changes in the gut microbiota play a causal role in the development of liver disease in mouse models of CF. Our study will discover novel aspects of secretory epithelia physiology and innate immunity and clarity if changes in the gut microbiota play a possible causal role in CFLD. These studies represent a paradigm-shift in the understanding of the pathogenesis of CFLD and imply that treatment for CFLD should also control inflammation and the impact of the intestinal microbiota. The outcome of this project will lay the foundation for novel intervention strategies that will have an impact on the management of CFLD and other cholangiopathies. !

总结 囊性纤维化（CF）是一种常见的临床上严重的遗传性疾病，由CFTR突变引起， 一种膜蛋白，在许多分泌上皮细胞中调节氯化物和液体分泌，包括 胆管树囊性纤维化肝病（CFLD）是一种慢性胆管病，最终可演变为 硬化性胆管炎和局灶性胆汁性肝硬化。这种疾病的发病机制还不清楚， 治疗限于给予利胆胆汁酸，或在选定的情况下，肝移植。 CFLD一直被经典地认为是由胆固醇引起的胆汁分泌受损的结果。 CFTR通道功能缺陷。然而，虽然CF的胆汁分泌普遍减少， CFLD的自发性发展不太常见，这表明遗传和/或获得性因素在 玩吧我们以前的研究表明，胆汁先天免疫系统对内毒素的耐受性降低， 在CFLD中起主要的致病作用。我们发现从Cftr-KO小鼠中分离的胆管细胞 当暴露于TLR 4配体时，NF-κB活性更高，并分泌大量的炎性细胞因子 LPS。我们还证明，在CF缺陷的胆管细胞中，TLR 4被不受限制的 Src家族激酶（SFK）的功能，缺陷CFTR的结果。这种机制也存在于 来源于ΔF508突变纯合的人iPSC的胆管细胞。此外，新奇刺激 初步数据显示，CFTR-KO小鼠的肠道微生物群在出生时就已经与WT同窝小鼠不同， 并且倾向于更促炎性的植物群的流行。 在本申请中，我们将测试CFLD可能是由遗传因素和基因突变的组合引起的假设。 影响胆管上皮先天免疫的突变，沿着微生物群组成的变化， 增加肠道通透性。特别是，（1）我们将使用iPSC技术来剖析 功能不同的CFTR突变对导致人类促炎表型的机制的影响 （2）我们将研究肠道微生物群的变化是否在胆管细胞中起因果作用。 CF小鼠模型中肝脏疾病的发展。 我们的研究将发现分泌上皮生理学和先天免疫的新方面， 肠道微生物群的变化在CFLD中起着可能的因果作用。这些研究代表了一种范式转变， 了解CFLD的发病机制，并暗示CFLD的治疗还应控制 炎症和肠道微生物群的影响。该项目的成果将奠定基础， 新的干预策略将对CFLD和其他胆管疾病的管理产生影响。 !