Employing Toxoplasma gondii virulence mutants to examine protective immunity

利用弓形虫毒力突变体检测保护性免疫

基本信息

批准号：
7742609
负责人：
Angela Marie Pollard
金额：
$ 3.85万
依托单位：
UNIVERSITY OF WISCONSIN-MADISON
依托单位国家：
美国
项目类别：
财政年份：
2008
资助国家：
美国
起止时间：
2008-01-01 至 2010-08-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/7742609
关键词：
Acquired Immunodeficiency Syndrome Acute Bioterrorism Birds Brain Categories Cells Chronic Phase Code Complement Complementary DNA Cyst Cytokine Activation Databases Dose Drug Delivery Systems Encephalitis Exons Fetus Genes Goals Immune Sera Immune response Immunity Immunocompetent Immunocompromised Host Immunofluorescence Microscopy Individual Infection Injection of therapeutic agent Introns Knock-out Laboratories Lethal Dose 50 Libraries Life Location Measurement Mus Mutagenesis Myocarditis Nervous System Trauma Oocysts Organ Organ Transplantation Parasites Patients Pharmaceutical Preparations Phenotype Pregnant Women Process Processed Genes Proteins Race Recombinant Proteins Research Risk Staging Testing Toxoplasma gondii Toxoplasmosis Transplant Recipients Vaccines Virulence Virulent Western Blotting cytokine fetal in vivo insight mutant novel therapeutics obligate intracellular parasite pathogen protein expression

项目摘要

DESCRIPTION (provided by applicant): Toxoplasma gondii is an obligate intracellular parasite that infects nearly all mammalian and avian nucleated cells. Infection of immunocompetent individuals with T. gondii is generally asymptomatic; however, toxoplasmosis can have severe implications in fetuses and immunocompromised individuals, such as AIDS patients and organ transplant recipients. Virulence mutants have been generated and identified in a signature-tagged mutagenesis library. The proposed research will characterize mutants from the library that are less virulent and unable to cause a typical acute infection. The mutants will be used to outline a protective immunity profile and provide insight into possible drug targets to limit infection of T. gondii in individuals most at risk for severe toxoplasmosis. T. gondii virulence mutants identified in an in vivo screen will be complemented to confirm the gene causing the mutant phenotype. The expression level and location of the protein product of the virulence gene will be determined. A knockout mutant of the virulence genes will be constructed and used to immunize mice before injection of a lethal dose of T. gondii. Efficiency of protective immunity will be quantified by change in LD50 and the number of cysts per brain during the chronic phase of infection. The protective profile will be examined through measurements of cytokines induced in mice and dissemination of the parasites during infection. Toxoplasma gondii is a parasitic pathogen that can cause severe and life-threatening illnesses in fetuses and immunocompromised individuals, including AIDS patients and transplant recipients. The proposed research will utilize acute virulence mutants to examine protective immunity and provide insight into possible drug targets to protect these individuals from serious infection with T. gondii.

描述（由申请人提供）：弓形虫Gondii是一种强制性细胞内寄生虫，几乎感染了所有哺乳动物和禽类核细胞。免疫能力的gondii的感染通常是无症状的。但是，弓形虫病可能对胎儿和免疫功能低下的个体具有严重影响，例如艾滋病患者和器官移植受者。毒力突变体已在标记标签的诱变文库中产生和鉴定。拟议的研究将表征来自文库的突变体，这些突变体毒性较低，无法引起典型的急性感染。这些突变体将用于概述保护性免疫力，并提供对可能的药物靶标的深入了解，以限制最有严重弓形虫病风险的个体中gondii的感染。在体内筛选中鉴定出的gondii毒力突变体将得到补充，以确认引起突变表型的基因。将确定毒力基因的蛋白质产物的表达水平和位置。在注射致死剂量的T. gondii之前，将构建毒力基因的基因敲除突变体并用于免疫小鼠。在慢性感染期，LD50的变化和每个大脑的囊肿数量将量化保护性免疫的效率。保护性谱将通过测量小鼠诱导的细胞因子和感染过程中寄生虫的传播进行检查。弓形虫Gondii是一种寄生虫病原体，可导致胎儿和免疫功能低下的个体，包括艾滋病患者和移植受者，引起严重且威胁生命的疾病。拟议的研究将利用急性毒力突变体检查保护性免疫，并洞悉可能的药物靶标，以保护这些个体免受T. gondii的严重感染。