Role of IL-18 in Crohn's Disease (CD)

IL-18 在克罗恩病 (CD) 中的作用

• 批准号: 7682959
• 负责人: Theresa Torres Pizarro
• 金额: $ 28.89万
• 依托单位: CASE WESTERN RESERVE UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2000
• 资助国家: 美国
• 起止时间: 2000-07-01 至 2012-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7682959
• 关键词: Accounting; Acute; Address; Affect; Alleles; Animal Model; Autoimmune Diseases; Automobile Driving; Binding; Biological Assay; Biological Models; Biopsy; Blood specimen; Bone Marrow; Bone Marrow Transplantation; CCL2 gene; Candidate Disease Gene; Cell Line; Cells; Characteristics; Chimera organism; Chronic; Chronic Phase; Chronic Phase of Disease; Classification; Colitis; Complex; Crohn' s disease; DNA Probes; Dendritic Cells; Development; Disease; Disease susceptibility; Dose; Electrophoretic Mobility Shift Assay; Environmental Risk Factor; Epithelial; Epithelial Cells; Etiology; Evaluation; Experimental Animal Model; Experimental Models; Family; Foundations; Funding; Gene Expression; Gene Expression Regulation; Genes; Genetic; Genetic Markers; Genetic Polymorphism; Genetic Predisposition to Disease; Genetic Variation; Genotype; Goals; Haplotypes; Human; IL18 gene; Ileitis; Immune; Immune response; Immune system; In Vitro; Individual; Inflammation; Inflammatory; Inflammatory Bowel Diseases; Inflammatory disease of the intestine; Insulin-Dependent Diabetes Mellitus; Interleukin-11; Interleukin-18; Intestines; Knowledge; Laboratories; Linkage Disequilibrium; Measures; Mediating; Messenger RNA; Modality; Modeling; Molecular; Molecular Biology Techniques; Mouse Strains; Mucosal Immune Responses; Mucous Membrane; Multiple Sclerosis; Mus; Organ; Pathogenesis; Patients; Pattern; Phase; Plasma; Play; Population; Population Control; Predisposition; Production; Promoter Regions; Proteins; Quantitative Trait Loci; Regulation; Regulator Genes; Reporter; Reporting; Research Personnel; Research Proposals; Rheumatoid Arthritis; Role; Sarcoidosis; Screening procedure; Severity of illness; Single Nucleotide Polymorphism; Site-Directed Mutagenesis; Sodium Dextran Sulfate; Source; Specificity; Staging; Subgroup; Susceptibility Gene; Testing; Time; Tissues; Transcriptional Regulation; Transfection; Ulcerative Colitis; Variant; Virginia; Whole Blood; Wild Type Mouse; Work; base; cell type; chemokine; clinical phenotype; cytokine; design; disorder control; genetic linkage; genetic variant; in vivo; macrophage; mouse model; novel; patient population; programs; promoter; repaired; research study; response; transcription factor; transmission process

Although the precise etiology is unknown, inflammatory bowel disease (IBD) is thought to occur as a result of a dysregulated mucosal immune response to environmental factors in a genetically predisposed individual. IL-18 is a cytokine that plays an important role in the pathogenesis of several chronic Thl-mediated disorders, including Crohn's disease (CD). In fact, a dramatic shift in IL-18 expression occurs during CD from intestinal epithelial cells (IEC) to mucosal immune cells (i.e. macrophages and dendritic cells), as the severity of disease increases. In addition, recent evidence supports the role of IL-18 as a protective factor during the acute phase of mucosal immune responses, when IEC are the primary source of IL-18. This novel function for IL-18 contrasts with the pathogenic role IL-18 is believed to play in more chronic phases of Thl-mediated inflammation. A genetic basis for differences in IL-18 regulation and expression observed in IBD may exist since recent studies have reported the association of specific single nucleotide polymorphisms (SNPs) in the IL-18 promoter region and several autoimmune diseases. Therefore, using genetic and molecular biology techniques as well as experimental models intestinal inflammation, the present study is designed to investigate the specific genetic factors that regulate IL-18 synthesis and to determine the precise function of epithelial and immune cell-derived IL-18 in the acute versus chronic phases of IBD. The central hypothesis of the present proposal is that IL-18plays a key role in regulating normal innate immune responses in the gut mucosa and dysregulation of IL-18 may result in chronic intestinal inflammation characteristic of IBD. The following three specific aims are proposed to test this hypothesis: 1) Determine the relationship between polymorphisms in the IL-18 promoter region and IBD. The role of IL-18 in IBD susceptibility will be defined using an association approach by screening for recently described IL-18 promoter polymorphisms and performing case association studies of these genetic markers in well-characterized IBD and control populations. IBD multiplex families will also be used to test linkage disequilibrium between these marker loci and putative disease susceptibility loci in order to further characterize the transmission pattern of allelic variants. 2) Define the mechanismCs) of polymorphic IL-18 gene regulation in different mucosal cell populations. The functional relevance of IL-18 promoter polymorphisms will be achieved by creation of reporter constructs, site-directed mutagenesis experiments, and in vitro transfection assays in epithelial and macrophage cell lines. In addition, differential transcription factor binding and subsequent transcriptional regulation will be assessed in order to determine how the IL- 18 gene is differentially regulated by IL-18 promoter polymorphisms, and if transcriptional control varies among different intestinal cell types. 3) Evaluate the specific role of IL-18 derived from different gut mucosal cell populations in an in vivo setting using experimental models of intestinal inflammation. The extent and severity of disease will be assessed in mice genetically- and immunologically-manipulated to produce IL-18 in either hemopoietic- (i.e. immune cells) or non-hemopoietic-cells (i.e. epithelial cells) following the induction of acute or chronic intestinal inflammation. These experiments will mechanistically address, in an in vivo setting, if IL-18 derived from specific mucosal cell populations and expressed during the acute versus chronic phases of disease, are involved in the pathogenesis of IBD. The ultimate goal of the present research proposal is to define the precise role of IL-18 in CD in order to develop specific treatment modalities aimed at modifying the natural course of this devastating disease.

虽然确切的病因尚不清楚，但炎症性肠病（IBD）被认为是由于炎症因子的失调而发生的。 在遗传易感个体中对环境因素的粘膜免疫应答。IL-18是一种细胞因子， 在包括克罗恩病（CD）在内的几种慢性Thl介导的疾病的发病机制中起重要作用。事实上，一个戏剧性的 在CD过程中，IL-18表达发生从肠上皮细胞（IEC）到粘膜免疫细胞（即巨噬细胞和 树突状细胞），随着疾病严重程度的增加。此外，最近的证据支持IL-18作为保护因子的作用 在粘膜免疫应答的急性期，IEC是IL-18的主要来源。IL-18的新功能 与IL-18的致病作用相反，IL-18被认为在Th1介导的炎症的更慢性阶段起作用。遗传基础 在IBD中观察到的IL-18调节和表达的差异可能存在，因为最近的研究报告了 IL-18启动子区的特异性单核苷酸多态性（SNP）与几种自身免疫性疾病。因此用 遗传和分子生物学技术以及实验模型肠道炎症，本研究旨在 研究调节IL-18合成的特异性遗传因子，并确定上皮细胞和免疫细胞的精确功能。 细胞来源的IL-18在IBD的急性期与慢性期。本研究的中心假设是IL-18在细胞内起着重要的作用。 IL-18在调节肠粘膜正常先天免疫应答中的关键作用和失调可能导致慢性 IBD特征性肠道炎症。提出了以下三个具体目标来检验这一假设：1）确定 IL-18启动子区多态性与IBD的关系。IL-18在IBD易感性中的作用将是 通过筛选最近描述的IL-18启动子多态性并进行病例分析， 这些遗传标记在充分表征的IBD和对照人群中的关联研究。IBD多重家族也将被 用于检测这些标记基因座和推定的疾病易感基因座之间的连锁不平衡，以进一步表征 等位基因变异的传播模式2)明确不同粘膜组织中IL-18基因多态性调控的机制 细胞群IL-18启动子多态性的功能相关性将通过创建报告构建体来实现， 定点诱变实验，以及在上皮和巨噬细胞系中的体外转染测定。此外，本发明还提供了一种方法， 将评估差异转录因子结合和随后的转录调节，以确定IL-10如何与IL-10结合。 IL-18基因受IL-18启动子多态性的差异调节，如果转录控制在不同的肠道组织中存在差异， 细胞类型。3)在体内环境中使用以下方法评价源自不同肠粘膜细胞群的IL-18的特异性作用： 肠道炎症的实验模型。疾病的程度和严重程度将在小鼠中进行遗传评估， 免疫操作以在造血细胞（即免疫细胞）或非造血细胞（即上皮细胞）中产生IL-18 细胞）。这些实验将机械地解决，在一个 如果IL-18来源于特定的粘膜细胞群，并在急性期与慢性期表达， 疾病，参与了IBD的发病机制。本研究提案的最终目标是确定 IL-18在CD中的作用，以开发旨在改变这种毁灭性疾病的自然病程的特定治疗方式。

项目成果

Central role of the gut epithelial barrier in the pathogenesis of chronic intestinal inflammation: lessons learned from animal models and human genetics.

肠道上皮屏障在慢性肠道炎症发病机制中的核心作用：从动物模型和人类遗传学中汲取的经验教训。

• DOI: 10.3389/fimmu.2013.00280
• 发表时间: 2013-09-17
• 期刊: Frontiers in immunology
• 影响因子: 7.3
• 作者: Pastorelli L;De Salvo C;Mercado JR;Vecchi M;Pizarro TT
• 通讯作者: Pizarro TT

The role of IL-33 in gut mucosal inflammation.

• DOI: 10.1155/2013/608187
• 发表时间: 2013
• 期刊: Mediators of inflammation
• 影响因子: 4.6
• 作者: Pastorelli L;De Salvo C;Vecchi M;Pizarro TT
• 通讯作者: Pizarro TT

Central role of IL-17/Th17 immune responses and the gut microbiota in the pathogenesis of intestinal fibrosis.

IL-17/TH17免疫反应和肠道菌群在肠纤维化发病机理中的中心作用。

• DOI: 10.1097/mog.0000000000000119
• 发表时间: 2014-11
• 期刊: Current opinion in gastroenterology
• 影响因子: 2.5
• 作者: Ray S;De Salvo C;Pizarro TT
• 通讯作者: Pizarro TT

The primary defect in experimental ileitis originates from a nonhematopoietic source.

• DOI: 10.1084/jem.20050407
• 发表时间: 2006-03-20
• 期刊: The Journal of experimental medicine
• 作者: Olson TS;Reuter BK;Scott KG;Morris MA;Wang XM;Hancock LN;Burcin TL;Cohn SM;Ernst PB;Cominelli F;Meddings JB;Ley K;Pizarro TT
• 通讯作者: Pizarro TT