Factors Mediating Host Resistance to Chlamydia trachomatis

介导宿主对沙眼衣原体抵抗力的因素

基本信息

批准号：
8288686
负责人：
MICHAEL N STARNBACH
金额：
$ 46.61万
依托单位：
HARVARD MEDICAL SCHOOL
依托单位国家：
美国
项目类别：
财政年份：
2006
资助国家：
美国
起止时间：
2006-02-01 至 2015-06-30
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/8288686
关键词：
Affect Alleles Amino Acids Animal Model Bacterial Infections Bacterial Sexually Transmitted Diseases Cataloging Catalogs Cell Communication Cell Culture Techniques Cells Chlamydia Chlamydia Infections Chlamydia trachomatis Chromosome Mapping Chronic Chronic Disease Cleaved cell Cytosol Development Disease Ectopic Pregnancy Engineering Enzymes Epithelium Family Genes Genetic Screening Genital system Global Change Goals Grant Growth Growth and Development function Guanosine Triphosphate Phosphohydrolases Host resistance Human Immune response Immunity In Vitro Individual Induced Mutation Infection Infertility Interferons Lead Link Maps Mass Spectrum Analysis Mediating Methods Morbidity - disease rate Mouse Strains Mus Organism Pathogenesis Pathology Pathway interactions Pelvic Inflammatory Disease Peptide Hydrolases Prevalence Proteins Proteome Proteomics Resistance Screening procedure Severities Stable Isotope Labeling Techniques Testing Time Transgenes Variant Woman Work combat cytokine genital infection hormone regulation in vivo in vivo Model indole-2,3-dioxygenase medical schools mouse model novel novel strategies pathogen response time use

项目摘要

DESCRIPTION (provided by applicant): Infection with Chlamydia trachomatis is responsible for significant morbidity throughout the world. Chronic genital infections with C. trachomatis can lead to pelvic inflammatory disease, infertility, and other complications in women. Our overall goal in this grant is to define how C. trachomatis interacts with and manipulates the mammalian host during infection. In the previous project period we focused on a large-scale forward genetic screen in mice to map variant alleles that affect resistance to C. trachomatis. We identified a family of Immunity-Related-GTPases (IRGs) as responsible for mouse resistance to C. trachomatis. However in humans, IRGs are not responsible for C. trachomatis resistance; instead humans resist infection through the expression of indole-2,3-dioxygenase (IDO). The identification of IRGs and IDO as the key differences between mice and humans with regard to IFNg-mediated resistance leads us now to propose the development of a mouse model that mimics human infection with C. trachomatis. To achieve this goal we will engineer strains of humanized mice in which the mouse-specific immune response driven IRGs is replaced with the human response that depends on IDO expression. Currently, no small animal model exists that recapitulates the chronic disease as it manifests itself in humans, particularly the prolonged or recurring infections that cause pathologies of the genital tract and infertility in humans. We have also shown that a number of C. trachomatis protein effectors are translocated into the host cell cytosol during infection where they cleave or otherwise alter host proteins. Because alteration of host cell protein stability appears to be a general strategy used by C. trachomatis, we are applying two novel screening methods called "stable isotope labeling with amino acids in cells culture" (SILAC) and "Global Protein Stability" (GPS) to analyze, on a global scale, which host proteins are perturbed during infection with C. trachomatis. Once we have identified host proteins stabilized or destabilized during C. trachomatis infection, we will test whether reducing or increasing the prevalence of these proteins in cells impairs C. trachomatis development. Although pathogen-induced alterations of the host are a key to pathogenesis, it has not previously been possible to simultaneously assess the impact of infection on individual host proteins at the scale now possible with these approaches. The methods explored in this application allow, for the first time, an appreciation of how bacterial infection globally regulates host cell proteins and pathways beyond the transcriptional level. Understanding the interaction of C. trachomatis with its human host requires a large-scale approach to catalog the changes C. trachomatis induces in host proteins during infection. Once these proteins and the pathways in which they act are understood, the impact of disrupting these Chlamydia-induced manipulations can only be appreciated using small animal models that accurately reflect the pathogenesis of human C. trachomatis infection.

描述（由申请人提供）：沙眼衣原体感染负责全世界的大量发病率。慢性生殖器感染带有沙aratomatis，会导致骨盆炎症性疾病，不育症和其他并发症。我们在这笔赠款中的总体目标是定义C. c. trachomatis在感染过程中如何与哺乳动物宿主相互作用并操纵。在上一个项目期间，我们专注于小鼠的大规模正向遗传筛选，以绘制影响对沙眼甲状腺梭安会的抗性的变体等位基因。我们确定一个与免疫相关的GTPase（IRG）家族负责小鼠对沙眼的耐药性。然而，在人类中，IRG不对沙眼梭状芽孢杆菌抗性负责。相反，人类通过吲哚-2,3-二氧酶（IDO）的表达来抵抗感染。 IRG和IDO鉴定为小鼠和人类在IFNG介导的抗性方面的关键差异，这使我们现在提出了模拟人类感染的小鼠模型的发展。为了实现这一目标，我们将设计人源化小鼠的菌株，其中小鼠特异性免疫反应驱动的IRG被替换为依赖IDO表达的人类反应。当前，没有小动物模型概括了慢性疾病，因为它在人类中表现出来，尤其是引起人类生殖道和不育的病态的长期或反复感染。我们还表明，在感染期间，许多沙眼曲霉蛋白效应子被转移到宿主细胞胞质中，它们在裂解或以其他方式改变宿主蛋白。由于宿主细胞蛋白稳定性的改变似乎是梭状芽孢杆菌使用的一般策略，因此我们正在应用两种新颖的筛选方法，称为“稳定的同位素标记在细胞培养中使用氨基酸稳定的同位素标记”（SILAC）和“全球蛋白质稳定性”（GPS）（GPS）（GPS）（GPS）在全球范围内分析，在全球范围内，宿主蛋白在宿主蛋白中受到疾病的感染。一旦我们确定了在沙眼梭状芽孢杆菌感染期间稳定或不稳定的宿主蛋白，我们将测试在细胞中降低或增加这些蛋白质的患病率会损害沙眼梭状芽胞盘发育。尽管病原体诱导的宿主改变是发病机理的关键，但以前没有可能通过这些方法同时评估感染对单个宿主蛋白的影响。在本应用中探索的方法首次允许对细菌感染如何调节宿主细胞蛋白和转录水平以外的途径的欣赏。了解沙眼梭状芽孢杆菌与其人类宿主的相互作用需要大规模的方法来分类在感染过程中宿主蛋白诱导的变化。一旦这些蛋白质及其作用的途径被理解，只有使用准确反映人梭菌感染的发病机理的小动物模型，才能理解破坏这些衣原体诱导的操作的影响。