The Central Role of IL-33 in Immune-Mediated Scarring

IL-33 在免疫介导的疤痕形成中的核心作用

• 批准号: 9001805
• 负责人: Sergei P. Atamas
• 金额: --
• 依托单位: BALTIMORE VA MEDICAL CENTER
• 依托单位国家: 美国
• 财政年份: 2015
• 资助国家: 美国
• 起止时间: 2015-04-01 至 2019-03-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9001805
• 关键词: Address; Affect; Animal Model; Anti-Inflammatory Agents; Anti-inflammatory; Asthma; Attenuated; Binding; Bleomycin; Breathing; CCL2 gene; COL1A1 gene; COL1A2 gene; Cell Culture Techniques; Cell Nucleus; Cell Surface Receptors; Cells; Chromatin; Cicatrix; Collagen; Collagen Gene; Connective Tissue; Cytokine Signaling; Data; Deposition; Development; Disease; Disease Pathway; Dust; Endothelial Cells; Epithelial; Extracellular Matrix; Fibroblasts; Fibrosis; Future; Gene Activation; Gene Delivery; Gene Expression; Genes; Genetic Transcription; Goals; Health; Healthcare; Heart; Human; Hypersensitivity; Immune; Immune response; Immunosuppressive Agents; Inflammation; Inflammatory; Injury; Interleukin-1; Interleukin-13; Interleukin-4; Interleukin-6; Interleukins; Investigation; Kidney; Lead; Left; Life; Ligands; Literature; Liver; Lung; Lymphocyte; MMP3 gene; Macrophage Inflammatory Protein-1; Maps; Matrix Metalloproteinases; Mediating; Military Personnel; Modeling; Mus; Necrosis; Nuclear; Organ; Parasites; Pathogenesis; Pathway interactions; Patients; Personal Satisfaction; Play; Poison; Poly I-C; Production; Proteins; Publishing; Radiation; Regulation; Research; Role; Sentinel; Smooth Muscle; Source; TLR3 gene; TLR4 gene; TNF gene; Therapeutic immunosuppression; Tissue Therapy; Tissues; Transcriptional Regulation; Veterans; adaptive immunity; base; cell type; cytokine; experience; extracellular; functional disability; immune activation; improved; in vivo; indium-bleomycin; innovation; macrophage; mouse model; new therapeutic target; older patient; particle; promoter; public health relevance; response

DESCRIPTION (provided by applicant): Exaggerated scarring, or fibrosis, complicates a spectrum of diseases, occurs in all organs, and can be relentless, debilitating, and deadly. It is particularly prevalent in older patients and thoe who have experienced military exposures, posing a serious problem for veterans. Exaggerated innate and adaptive immune responses drive fibrosis, yet the exact mechanisms remain incompletely understood. Recent findings suggest a role for interleukin (IL)-33 in the pathogenesis of fibrosis. IL-33 exists in two forms and has a dual activity. Intranuclear IL-33 (INIL33) is bound to chromatin and appears to regulate gene expression. By contrast, extracellular IL-33 (EXIL33) acts by binding to the cell-surface receptor T1/ST2 and facilitating Th2 responses. The activities of EXIL33 are under active investigation, whereas the activities of INIL33 have been underappreciated and not studied in detail or in association with disease. Our data suggest that fibrosis is driven primarily (yet not exclusively) by INIL33. The levels of INIL3 are elevated in tissues of patients with fibrosis as well as in the mouse model of bleomycin injury, in which the INIL33 form predominates over EXIL. Gene delivery of INIL33 in cell culture and in the animal model leads to collagen accumulation, increased production of profibrotic cytokines and matrix metalloproteinases, as well as Smad3 activation, all of which are known to contribute to fibrosis. When combined with bleomycin injury, INIL33 potentiates collagen accumulation and the expression of profibrotic cytokines. There is minimal, if any, conversion of INIL33 to EXIL33, no signs of Th2 activation, and gene deficiency of T1/ST2 has minimal, if any, attenuating effect on INIL33-driven fibrosis. We hypothesize that INIL33 is a T1/ST2-independent, Th2-independent, upstream activator of multiple profibrotic mechanisms and that elevated expression of INIL33 in fibroblasts contributes to collagen deposition by these cells through direct and indirect mechanisms. The following Specific Aims will be addressed: 1. Functionally map the IL-33 molecule to identify regions in this protein that confer nuclear localization, chromatin binding, and transcriptional regulation in cultured primary human fibroblasts and in mice in vivo. 2. Define the relative roles of direct mechanisms (binding to the collagen promoter and upregulating collagen gene transcription) and indirect mechanisms (both T1/ST2-dependent and -independent regulation of profibrotic cytokines and matrix metalloproteinases) of profibrotic regulation of fibroblasts by IL-33 in cell culture. 3. Delineate the pathophysiological roles of fibroblast-specific expression of IL-33 and of the T1/ST2 cell-surface receptor in vivo by determining the effects of fibroblast-specific IL-33 deficiency, ubiquitous IL-33 deficiency, and ubiquitous T1/ST2 deficiency on inflammation and fibrosis in the bleomycin injury model. Successful completion of these studies will clarify the role and mechanisms of fibroblast activation by INIL-33, laying the groundwork for future development of rational IL-33-targeting antifibrotic strategies.

描述（由申请人提供）： 夸张的疤痕或纤维化使各种器官发生在所有器官中都会复杂化，并且可能是无情的，使人衰弱和致命的。在经历过军事曝光的老年患者和thoe中，这尤其普遍，这给退伍军人带来了严重的问题。夸张的先天和适应性免疫反应促进了纤维化，但确切的机制仍未完全理解。最近的发现表明，白介素（IL）-33在纤维化发病机理中的作用。 IL-33以两种形式存在，具有双重活动。核内IL-33（INIL33）注定为染色质，并且似乎调节基因表达。相比之下，细胞外IL-33（EXIL33）通过与细胞表面受体T1/ST2结合并促进TH2反应来起作用。 EXIL33的活性正在积极研究中，而INIL33的活动被低估了，没有详细研究或与疾病有关。我们的数据表明，纤维化主要是由INIL33驱动的（但不是仅限）。 INIL3的水平在纤维化患者以及博来霉素损伤的小鼠模型中的组织中升高，其中Inil33形成的占主导地位以外。 INIL33在细胞培养和动物模型中的基因递送导致胶原蛋白的积累，纤维化细胞因子和基质金属蛋白酶的产生增加，以及SMAD3激活，所有这些都会导致纤维化。当与博来霉素损伤结合使用时，INIL33增强了胶原蛋白的积累和纤维化细胞因子的表达。 INIL33转换为Exil33，没有Th2激活的迹象，T1/ST2的基因缺乏的转化很小（如果有的话），对INIL33驱动的纤维化的影响很小。我们假设INIL33是多种纤维化机制的T1/ST2独立于Th2独立的上游激活剂，并且在成纤维细胞中INIL33的表达升高，通过直接和间接机制促进了这些细胞的胶原蛋白沉积。将解决以下具体目的：1。在功能上绘制IL-33分子，以鉴定该蛋白质中赋予核定位，染色质结合和转录调节的蛋白质中的区域，并在体内培养的原发性人成纤维细胞和小鼠中的转录调节。 2。定义直接机制（与胶原蛋白启动子的结合并上调胶原基因转录）和间接机制（T1/ST2依赖性和非依赖性调节纤维化细胞因子和基质金属蛋白酶）的相对作用。 3。描绘 通过确定成纤维细胞特异性IL-33缺乏症，普遍存在的IL-33缺乏症和无处不在的T1/ST2缺乏症对体内炎症和纤维化症的影响，IL-33和T1/ST2细胞表面受体在体内的病理生理作用和T1/ST2细胞表面受体在体内的病理生物学作用。这些研究的成功完成将阐明INIL-33激活成纤维细胞激活的作用和机制，为未来发展有理IL-33靶向抗纤维化策略的发展奠定了基础。