CFTR modulates innate immune response in the biliary epithelium. Role in the path

CFTR 调节胆管上皮的先天免疫反应。

基本信息

批准号：
8836532
负责人：
Mario Strazzabosco
金额：
$ 36.21万
依托单位：
YALE UNIVERSITY
依托单位国家：
美国
项目类别：
财政年份：
2013
资助国家：
美国
起止时间：
2013-05-01 至 2016-03-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/8836532
关键词：
Agonist Animal Model Anti-Inflammatory Agents Anti-inflammatory Bicarbonates Bile fluid Biliary Biliary cirrhosis Binding Binding Proteins Biochemical Cells Cholestasis Chronic Comparative Study Cystic Fibrosis Cystic Fibrosis Transmembrane Conductance Regulator Development Dextrans Disease Endotoxemia Epithelial Epithelium Experimental Models Ferrets Fluids and Secretions Foundations Functional disorder Future Genetic Health Hepatobiliary Hereditary Disease Human Immune response Immunology In Vitro Inflammation Inflammatory Inflammatory Response Knowledge Link Liver Liver diseases Mediating Membrane Proteins Modeling Molecular Mus Natural Immunity Nuclear Receptors Oral Administration PPAR gamma Pathogenesis Pathway interactions Phosphorylation Pioglitazone Play Process Production Property Protein Tyrosine Kinase Quality of life Regulation Reporting Resistance Role Sclerosing Cholangitis Signal Transduction TLR4 gene Testing Therapeutic Therapeutic Studies acquired factor base biliary tract cholangiocyte clinically significant cystic fibrosis patients cytokine disease-causing mutation genetic regulatory protein in vivo inhibitor/antagonist insight liver injury liver transplantation novel novel therapeutic intervention prevent response src-Family Kinases treatment strategy

项目摘要

DESCRIPTION (provided by applicant): Cystic Fibrosis (CF) is a common and clinically severe genetic disease, caused by mutations in CFTR, a membrane protein that mediates Cl- and fluid secretion in a number of secretory epithelia, including the biliary tree. About 30% of CF patients present biochemical liver abnormalities and about 10% of these develop clinically significant liver disease and hepatobiliary complications characterized by a chronic cholangiopathy that can eventually evolve into sclerosing cholangitis and focal biliary cirrhosis. Cystic Fibrosis liver disease (CFLD) negatively impacts the quality of life and survival of CF patients, and may require liver transplantation, however, the pathogenesis of this condition is not well understood. In Cftr-KO mice, bile flow and biliary secretion are reduced; however the spontaneous development of CFLD is extremely rare, suggesting that genetic and/or acquired factors other than cholestasis are at play. It has been shown that portal endotoxemia, induced by oral administration of dextrans specifically causes biliary damage in Cftr-KO mice, but not in their wild type littermates. Using this experimental model, we recently showed that biliary damage and inflammation caused by treatment with DSS in Cftr-KO mice were not prevented by restoring biliary secretion with nor-UDCA, and that, exposure of cultured CFTR-defective cholangiocytes to LPS in vitro, significantly increased cytokine secretion and NF-κB activity as compared to WT cells. The increased activation of NF-κB was prevented by inhibition of TLR4. We also found that the activity of Src, a tyrosine kinase involved in cell response to LPS, was upregulated in CF cells and resulted in an increased phosphorylation of TLR4. We propose that Src is the potential molecular link between CFTR and TLRs. In fact, treatment with Src inhibitor PP2 blocked TLR4 phosphorylation and NF-κB activation in response to LPS. We have also found that the expression and distribution of Csk and EBP-50, involved in Src regulation, were altered in Cftr-KO cholangiocytes. In this application, we will further investigate this novel paradigm shifting hypothesis, and in particular we will elucidate 1) the pathogenetic role of different TLRs in CFLD, 2) the role of Src in linking CFTR and TLR- mediated signaling and 3) the therapeutic value of PPARγ agonist as a strategy to inhibit the TLR/NF-κB pathway in CF cholangiocytes. These studies will be performed in Cftr-defective mice and in ferrets, a novel CF model that spontaneously develops CFLD. These studies will change our current understanding of the pathogenesis and treatment of CF-cholangiopathy. Furthermore, better knowledge of the regulation of TLR pathways in the biliary epithelium, will also provide important insights into the pathogenesis of other inflammation-mediated diseases of the epithelium, providing a firm foundation for future studies in the broader field of epithelial immunology.

描述（由适用提供）：囊性纤维化（CF）是一种常见且临床上严重的遗传疾病，是由CFTR突变引起的，CFTR是一种膜蛋白，一种介导许多秘密上皮的cl和液体分泌的膜蛋白，包括胆道树。约30％的CF 患者表现出生化肝脏异常，其中约10％出现了临床意义的肝脏疾病和肝胆疾病并发症，其特征在于慢性胆管造成的特征，最终可以演变成硬化性的胆管炎和局灶性胆汁性胆管炎。囊性纤维化肝病（CFLD）对CF患者的生活质量和存活产生负面影响，可能需要肝移植，但是，这种病的发病机理尚不清楚。在CFTR-KO小鼠中，胆汁流和胆道分泌减少；然而，以赞助商为中心的CFLD发展极为罕见，这表明除胆汁淤积以外的遗传和/或获得的因素正在发挥作用。已经表明，通过口服葡聚糖诱导的门户内毒素血症特异性地造成了CFTR-KO小鼠的胆道损伤，但不会在其野生型同窝仔中造成胆汁损伤。使用该实验模型，我们最近表明，通过恢复与Nor-udca的胆汁分泌的CFTR-KO小鼠治疗引起的胆道损伤和炎症，并且与细胞因子分泌和Nf-κB的细胞相比，培养的CFTR CFTR CFTR缺陷胆管细胞暴露于LPS对LPS的暴露显着增加了。增加激活通过抑制TLR4阻止NF-κB。我们还发现，在CF细胞中，SRC的活性是与细胞对LPS相关的酪氨酸激酶的活性，并导致TLR4的磷酸化增加。我们建议SRC是CFTR和TLR之间的潜在分子联系。实际上，用SRC抑制剂PP2治疗响应LPS，阻断了TLR4磷酸化和NF-κB活化。我们还发现，CFTR-KO胆管细胞中涉及SRC调控的CSK和EBP-50的表达和分布发生了变化。 In this application, we will further investigate this novel paradigm shifting hypothesis, and in particular we will elucidate 1) the pathogenic role of different TLRs in CFLD, 2) the role of Src in linking CFTR and TLR- mediated signaling and 3) the therapeutic value of PPARγ agonist as a strategy to inhibit the TLR/NF-κB pathway in CF cholangiocytes.这些研究将在CFTR缺陷的小鼠和雪貂中进行，这是一种新型的CF模型，该模型在赞助CFLD上进行。这些研究将改变我们目前对CF-胆管疾病的发病机理和治疗的理解。此外，更好地了解胆道上皮中TLR途径的调节，还将为上皮细胞的其他炎症介导的疾病的发病机理提供重要的见解，从而为在更广泛的上皮免疫学领域的未来研究提供了坚定的基础。