Trypanosoma cruzi cyclophilin 19 induced host inflammation

克氏锥虫亲环蛋白 19 诱导宿主炎症

• 批准号: 9299994
• 负责人: BRADFORD Scott MCGWIRE
• 金额: $ 23.19万
• 依托单位: OHIO STATE UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2017
• 资助国家: 美国
• 起止时间: 2017-02-06 至 2019-01-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9299994
• 关键词: Alleles; Area; Binding; Cardiac; Cardiomyopathies; Cell Line; Cell surface; Cells; Chagas Cardiomyopathy; Chagas Disease; Chronic; Cyclophilin A; Cyclophilins; Cytoplasm; Development; Disease; Engineering; Enzymes; Etiology; Extracellular Matrix; Fibrosis; Growth; Heart Diseases; Heart failure; Homologous Gene; Human; In Vitro; Incidence; Infection; Infection prevention; Inflammation; Inflammatory; Knock-out; Latin America; Mammalian Cell; Mediating; Metalloproteases; Molecular; Mus; Myocarditis; Parasitemia; Parasites; Pathogenesis; Pathologic; Pathologic Processes; Pathology; Peptidylprolyl Isomerase; Play; Production; Proteins; Recombinants; Role; Signaling Protein; Site; Small Interfering RNA; Specificity; Testing; Tissues; Trypanosoma cruzi; Work; coronary fibrosis; design; experimental study; extracellular; human disease; inhibitor/antagonist; knock-down; migration; mortality; mouse model; mutant; novel; small molecular inhibitor; small molecule inhibitor; therapy development; tool; vaccine development

PROJECT SUMMARY: Human infection by the parasite Trypanosoma cruzi leads to inflammatory cardiomyopathy (Chagas disease) which is the leading infectious cause of heart failure in Latin America. The incidence of Chagas disease is increasing worldwide through the migration of chronically infected people from endemic areas. The mechanisms by which the parasite causes inflammation and fibrosis of host tissues are multifactorial and incompletely understood. The focus of this proposal is the parasite protein cyclophilin 19 (Cyp19), a peptidyl-prolyl isomerase, which is expressed and secreted by all lifecycle stages of the parasite including the two keys stages that cause human disease. Our work has found that Cyp19 binds to human CD147 (aka, extracellular matrix metalloprotease inducer; EMMPRIN), a ubiquitous cell-surface signaling protein implicated in multiple hyper-inflammatory states. Engagement of CD147 by Cyp19 leads to the production of matrix metalloproteases analogous to the well-documented action of extracellular human cyclophilin A (a structural and functional human homologue of Cyp19) induced inflammation in a variety of human pathologic conditions including cardiac disease. Our hypothesis is that during parasite infection released Cyp19 acts both locally in tissues and systemically as a potent inducer of host tissue inflammation. This is relevant to the inflammation leading to cardiac fibrosis and the development of Chagas cardiomyopathy. The experiments outlined in this exploratory project are designed to test this hypothesis. In the first aim we will interrogate the interaction between parasite Cyp19 and human CD147 using purified Cyp19 and inactive enzyme mutants to test whether Cyp19 enzymatic activity is essential for this activation. Host cell lines engineered to lack expression of CD147 will be used to test the specificity of the induction of inflammation on CD147 and in parasite infection studies to understand the influence of CD147 on parasite infectivity and intracellular growth. Parasites lines engineered to express diminished Cyp19 will be used in host cell infection studies to test the effect of variable amounts of Cyp19, in the context of the parasite, on host infection and the induction of inflammation in CD147-dependent and –independent conditions. In the second aim we will determine the role of Cyp19 in the induction of tissue inflammation in a mouse model of infection. The effect of wildtype and enzymatically inactive Cyp19 proteins will be used to treat mice to determine if Cyp19 alone, in the absence of parasite infection, can induce tissue inflammation. Infection of mice with wildtype and Cyp19-deficient parasite lines will be compared for levels of parasitemia, induction of cardiac fibrosis and overall mortality. At the conclusion of this project we will understand whether Cyp19 contributes to T. cruzi infection and tissue pathogenesis and the results will provide the groundwork for further mechanistic studies on this pathologic process and the development of small molecule inhibitors for the potential treatment Chagas heart disease.

项目摘要：人类感染克氏锥虫寄生虫导致炎症 心肌病(恰加斯病)是拉丁美洲心力衰竭的主要感染性原因。这个 查加斯病的发病率在全世界范围内都在增加，因为慢性感染者从 地方病流行地区。寄生虫引起宿主组织炎症和纤维化的机制是 多因素的，不完全理解的。这项提案的重点是寄生虫蛋白亲环素19 (Cyp19)，是一种肽基-脯氨酰异构酶，在寄生虫的所有生命周期阶段都有表达和分泌 包括导致人类疾病的两个关键阶段。我们的工作发现Cyp19与人CD147结合 (又名细胞外基质金属蛋白酶诱导物；EMMPRIN)，一种普遍存在的细胞表面信号蛋白 牵涉到多种高炎症状态。Cyp19对CD147的参与导致了 类似于细胞外人亲环素A(A)已知作用的基质金属蛋白酶 Cyp2的结构和功能人类同源物在多种人类病理组织中引起炎症 包括心脏病在内的疾病。我们的假设是，在寄生虫感染期间，释放了Cyp19 在局部组织中和在系统中都是宿主组织炎症的有效诱因。这与以下内容相关 导致心脏纤维化和查加斯心肌病发展的炎症。这些实验 在这个探索性项目中概述的是旨在检验这一假设的。在第一个目标中，我们将审问 利用纯化的Cyp19和失活酶突变体研究寄生虫Cyp19与人CD147的相互作用 测试Cyp19酶活性是否是这种激活所必需的。缺乏基因工程的宿主细胞系 CD147的表达将被用来测试CD147诱导炎症的特异性和在 研究寄生虫感染以了解CD147对寄生虫感染性和细胞内生长的影响。 设计表达Cyp19缺失的寄生虫系将用于宿主细胞感染研究，以测试 在寄生虫的背景下，可变数量的Cyp19对宿主感染和诱导 CD147依赖和非依赖状态下的炎症。在第二个目标中，我们将确定角色 Cyp19在诱导小鼠组织炎症感染模型中的作用。野生型的影响和 酶失活的Cyp19蛋白将用于治疗小鼠，以确定在没有Cyp19的情况下，Cyp19单独 寄生虫感染，可引发组织炎症。野生型和Cyp19缺陷寄生虫对小鼠的感染 将比较不同品系的寄生虫血症水平、心脏纤维化的诱导和总死亡率。在 本项目的结论是，我们将了解Cyp19是否对克氏锥虫的感染和组织有贡献 其发病机制和研究结果为进一步研究其发病机制奠定了基础。 潜在治疗查加斯心脏病的小分子抑制剂的研究进展。