Role of Innate Immunity and Stat3 Activation in Colitis Mouse Model

先天免疫和 Stat3 激活在结肠炎小鼠模型中的作用

基本信息

批准号：
8485600
负责人：
Shervin Rabizadeh
金额：
$ 17.01万
依托单位：
CEDARS-SINAI MEDICAL CENTER
依托单位国家：
美国
项目类别：
财政年份：
2010
资助国家：
美国
起止时间：
2010-07-01 至 2015-06-30
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/8485600
关键词：
Acetylmuramyl-Alanyl-Isoglutamine Acute Address Adoptive Transfer Adult Affect American Anaerobic Bacteria Bacteria Bacteroides fragilis Binding Bone Marrow Bone Marrow Transplantation C57BL/6 Mouse CD4 Positive T Lymphocytes Caspase Cell Lineage Cells Chronic Colitis Colon Colorectal Cancer Crohn&apos s disease Data Defect Diagnostic Procedure Disease Enterobacteriaceae Epithelial Epithelial Cells Exhibits Family member Gastrointestinal tract structure Gene Mutation Genes Genotype Hematopoietic Hour Human Immune Immune response Immune system Immunohistochemistry Immunologics Immunology procedure In Vitro Individual Inflammation Inflammatory Inflammatory Bowel Diseases Interleukin-17 Intestines Investigation Knockout Mice Laboratories Life Light Link Metalloproteases Methods Modeling Molecular Morbidity - disease rate Mus Natural Immunity Nucleotides Outcome Pathogenesis Pathway interactions Patients Permeability Phenotype Play Proteins Public Health RIPK2 gene RNA analysis Receptor Signaling Regulation Relative (related person)Research Research Project Grants Resistance Rodent Role Secondary to Signal Pathway Signal Transduction Single Nucleotide Polymorphism Stat3 protein Structure Testing Time Toll-like receptors Toxin Ulcerative Colitis Virulence Factors Work Zinc base cytokine data modeling genome wide association study human disease improved in vivo insight interest mouse model novel novel diagnostics novel therapeutics pathogen public health relevance research study response transcription factor

项目摘要

DESCRIPTION (provided by applicant): Inflammatory bowel disease (IBD), Crohn's disease or ulcerative colitis, affects an estimated 1.4 million Americans and is manifested by chronic inflammation of the gastrointestinal tract with significant morbidity and, at times, life-threatening complications. IBD is proposed to result from a dysregulated mucosal immune (innate and adaptive) response to the colonic flora in genetically susceptible individuals. Bacteroides fragilis is a common human commensal residing in the colon. A subset of B. fragilis, enterotoxigenic B. fragilis (ETBF), has been associated with inflammatory diarrheal disease, IBD, and colorectal cancer. Our ETBF murine model data shows that colonization with ETBF leads to a proinflammatory response exhibiting a predominant Th17 (interleukin 17-secreting) CD4+ T cell infiltrate promoted by signal transducer and activator of transcription-3 (Stat3) in C57BL/6 mice. The presence of activated Stat3 as well as colitis is evident within hours of orogastric inoculation with ETBF. However, there have been no investigations to date regarding the role of the innate immune system in ETBF colitis. IL-17 skewing has been recently demonstrated in a different infectious model involving downstream products of the Nucleotide-binding oligomerization domain containing (NOD) innate immune pathway. There is a strong association of NOD2 gene mutations and Crohn's disease. Hence, this data supports that innate immune factors and signal transducer and activator of transcription 3 (Stat3) plays a major role in the ETBF mouse model of colitis providing insight into the genesis of Inflammatory Bowel Disease. The objective of this research project is to address the role of the innate immune signaling pathways, in particular the NOD/Rip2 and toll like receptor (TLR)/MyD88, in the ETBF-induced colitis model. We will test the hypothesis that MyD88-/- and Rip2-/- mice will exhibit enhanced ETBF-induced colitis and Stat3 activation. To that end, the following Specific Aims are proposed: Specific Aim 1: To evaluate the role of NOD/Rip2 and TLR/MyD88 innate immune pathways in response of ETBF induced colitis using various genetically manipulated mice; Specific Aim 2: To define the role of Stat3 activation in the pathogenesis of ETBF-induced colitis in the NOD/Rip2- and TLR/MyD88- deficient mice; Specific Aim 3: To determine the role of TLR/MyD88 and NOD/Rip2 deficiency in hematopoietic versus non-hematopoietic derived cells on Stat3 activation and the pathogenesis of ETBF-induced colitis by creating and utilizing chimeric mice derived via bone marrow (BM) transplantation. The project will use the murine (C57BL/6) model of ETBF-induced colitis and various immunologic assays, knock-out mice, bone marrow transplantation, immunohistochemistry, flow cytometery, cytokine and RNA analysis. The significance of this research is that it will allow insight into the dysregulated immune response to colonic bacteria associated with IBD, a disorder with substantial morbidity, with hopes for new therapeutic insights to this prevalent disease. PUBLIC HEALTH RELEVANCE: This study examines the role of innate immune system, specifically TLR and NOD receptor signaling pathways, and the role of signal transducer and activator of transcription 3 (Stat3) in a bacteria induced colitis mouse model. Information obtained from this study will allow insight into the dysregulated immune response associated with IBD, a disorder with substantial morbidity.

描述（由申请人提供）：炎症性肠病（IBD），克罗恩氏病或溃疡性结肠炎，估计有140万美国人，并由胃肠道的慢性炎症表现出明显的发病率，有时会威胁生命的并发症。提议IBD是由对遗传易感个体的结肠菌群的粘膜免疫（先天和适应性）反应引起的。细菌脆弱的脆弱是居住在结肠中的常见人类共生。脆弱芽孢杆菌的子集，肠毒素B. fragilis（ETBF）与炎症性腹泻病，IBD和结直肠癌有关。我们的ETBF鼠模型数据表明，带有ETBF的定殖导致促炎反应表现出由信号传感器和转录传感器的激活剂和C57BL/6小鼠中转录3（STAT3）的激活剂促进的主要TH17（白介素17分泌）CD4+ T细胞浸润。活化的STAT3和结肠炎的存在在与ETBF接种的小时内很明显。但是，迄今为止尚未对先天免疫系统在ETBF结肠炎中的作用进行调查。最近在涉及含有核苷酸结合寡聚域的下游产物（NOD）先天免疫途径的下游产物的不同感染模型中证明了IL-17偏斜。 NOD2基因突变与克罗恩病有很强的关联。因此，该数据支持了先天免疫因子和信号透射剂和转录3（STAT3）激活因子在结肠炎的ETBF小鼠模型中起主要作用，从而洞悉了炎症性肠病的起源。该研究项目的目的是解决先天免疫信号通路的作用，尤其是在ETBF诱导的结肠炎模型中点头/RIP2和TOL类似于受体（TLR）/MYD88。我们将检验以下假设：MyD88 - / - 和RIP2 - / - 小鼠将表现出增强的ETBF诱导的结肠炎和STAT3激活。为此，提出了以下特定目的：具体目的1：评估NOD/RIP2和TLR/MYD88先天免疫途径在ETBF诱导结肠炎中使用各种遗传操纵小鼠的作用；具体目的2：定义STAT3激活在NOD/RIP2-和TLR/MYD88-缺陷小鼠中ETBF诱导的结肠炎发病机理中的作用；具体目的3：确定TLR/MYD88和NOD/RIP2缺乏在造血与非造血细胞中的作用，以及通过创建和利用通过骨髓（BM）移植（BM）移植而产生和利用ETBF诱导的结肠炎的STAT3激活以及ETBF诱导的结肠炎的发作。该项目将使用ETBF诱导的结肠炎和各种免疫学测定，敲除小鼠，骨髓移植，免疫组织化学，流式细胞术，细胞因子和RNA分析的鼠（C57BL/6）模型。这项研究的意义在于，它将深入了解与IBD相关的结肠细菌的失调反应，这是一种具有很大的发病率的疾病，希望对这种普遍的疾病有新的治疗见解。公共卫生相关性：这项研究检查了先天免疫系统，特别是TLR和NOD受体信号通路的作用，以及在细菌诱导的结肠炎小鼠模型中，信号传感器和转录3（STAT3）激活剂的作用。从这项研究中获得的信息将使与IBD相关的免疫反应失调，这是一种具有很大发病率的疾病。