Role of Mycobacterium tuberculosis protease in pathogenesis and host response

结核分枝杆菌蛋白酶在发病机制和宿主反应中的作用

• 批准号: 7502359
• 负责人: Jyothi Rengarajan
• 金额: $ 7.96万
• 依托单位: EMORY UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2007
• 资助国家: 美国
• 起止时间: 2007-07-01 至 2011-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7502359
• 关键词: Active Sites; Antibody Formation; Apoptosis; Attenuated; B-Lymphocytes; Bacteria; Biochemical; Biological; Biological Assay; Biological Process; Calmette-Guerin Bacillus; Cells; Cellular Structures; Cessation of life; Cleaved cell; Collaborations; Complement; Data; Databases; Doctor of Philosophy; Endopeptidases; Environment; Epitopes; Future; Genes; Genome; Genus Mycobacterium; Goals; Growth; Human; Immune; Immune response; Immunity; Immunologics; In Vitro; Infection; Integration Host Factors; Life Style; Lipoproteins; Localized; Lung; Mediating; Modeling; Molecular; Mus; Mutate; Mycobacterium tuberculosis; Nature; Necrosis; Nitric Oxide; Pathogenesis; Pathology; Peptide Hydrolases; Peptide Signal Sequences; Phenotype; Physiological; Play; Population; Predisposition; Principal Investigator; Process; Proteins; Proteolytic Processing; Recombinants; Research Personnel; Rest; Role; Serine; Signal Transduction; Site; Specificity; Spleen; Structure; Surface; T-Lymphocyte; Testing; Therapeutic Intervention; Time; Tissues; Tuberculosis; Vaccines; Viral; Virulence Factors; attenuation; bacterial genetics; base; cell envelope; chemokine; cytokine; design; extracellular; in vivo; insight; intracellular protein transport; killings; lymph nodes; macrophage; microbicide; mutant; pathogen; programs; protein localization location; protein protein interaction; response; success; tool; vaccine development; yeast protein; yeast two hybrid system

DESCRIPTION (provided by applicant): Mycobacterium tuberculosis is a highly successful human pathogen that has evolved to survive within the host. Our long-term goals are to delineate the mechanisms by which M. tuberculosis interferes with the microbicidal functions of macrophages and evades host immune responses. Understanding the molecular mechanisms underlying M. tuberculosis- host interactions is important for designing therapeutic interventions and vaccine strategies. We have identified Rv2224c, a predicted protease, as being critical for survival in macrophages and in vivo. We hypothesize that Rv2224c is an important virulence factor that proteolytically cleaves M. tuberculosis substrates and modulates the host immune response. Our preliminary studies indicate that Rv2224c is exported to the cell envelope of mycobacteria and secreted extracellularly. A mutant disrupted in the protease is impaired for growth in macrophages and in vivo. Mice infected with a protease mutant show markedly reduced lung pathology and survive longer than wild type-infected mice. In this proposal will study the role of the protease in host-pathogen interactions. The specific aims are: 1. Molecular and biochemical characterization of Rv2224c and its potential substrate(s) in M. tuberculosis. We will study the localization of Rv2224c in mycobacteria and perform structure-function analysis of Rv2224c. We will investigate the biological activity and specificity of the protease by studying a candidate physiologic substrate. 2. Study the interaction of the protease with the host immune response in macrophages and in vivo. We will examine the nature of the immune response to Rv2224c mutant, specifically determine the role of T and B cells in immunity and perform structure-function analysis of protease interaction with the host in macrophages and in vivo. 3. Dissect the modulation of macrophage function by the protease. We will ask whether infection with the mutant elicits altered macrophage responses and test whether the Rv2224c::tn mutant is hyper-susceptible to IFNy-mediated immune responses. Finally, we will study whether Rv2224 directly interacts with host cell components using protein-protein interaction studies.

描述(申请人提供)：结核分枝杆菌是一种非常成功的人类病原体，已进化为在宿主内生存。我们的长期目标是阐明结核分枝杆菌干扰巨噬细胞杀菌功能和逃避宿主免疫反应的机制。了解结核分枝杆菌与宿主相互作用的分子机制对于设计治疗干预措施和疫苗策略非常重要。我们已经确定Rv2224c是一种预测的蛋白酶，对巨噬细胞和体内的生存至关重要。我们推测Rv2224c是一种重要的毒力因子，它能分解结核分枝杆菌的底物，调节宿主的免疫反应。我们的初步研究表明，Rv2224c输出到分枝杆菌的细胞膜上，并以细胞外的方式分泌。被破坏的蛋白水解酶突变体会损害巨噬细胞和体内的生长。与野生型感染的小鼠相比，感染了蛋白酶突变的小鼠的肺部病理明显减轻，存活时间更长。在这项建议中将研究蛋白酶在宿主-病原体相互作用中的作用。具体目的是：1.结核分枝杆菌Rv2224c及其潜在底物S的分子和生化特性研究。我们将研究Rv2224c在分枝杆菌中的定位，并对Rv2224c进行结构和功能分析。我们将通过研究一种候选的生理底物来研究该酶的生物学活性和特异性。2.研究该酶在巨噬细胞内和体内与宿主免疫反应的相互作用。我们将研究Rv2224c突变的免疫应答的性质，具体确定T和B细胞在免疫中的作用，并在巨噬细胞和体内进行蛋白酶与宿主相互作用的结构-功能分析。3.剖析了蛋白酶对巨噬细胞功能的调节作用。我们将询问感染突变体是否会引起巨噬细胞反应的改变，并测试Rv2224c：：Tn突变体是否对IFNy介导的免疫反应高度敏感。最后，我们将研究Rv2224是否通过蛋白质-蛋白质直接与宿主细胞成分相互作用 互动研究。

项目成果

Neutrophil extracellular trap (NET) levels in human plasma are associated with active TB.

• DOI: 10.1371/journal.pone.0182587
• 发表时间: 2017
• 期刊: PloS one
• 影响因子: 3.7
• 作者: Schechter MC;Buac K;Adekambi T;Cagle S;Celli J;Ray SM;Mehta CC;Rada B;Rengarajan J
• 通讯作者: Rengarajan J

Meeting report: The International Conference on Human Immunity to Tuberculosis.

会议报告：国际人类结核病免疫会议。

• DOI: 10.1016/j.tube.2012.05.003
• 发表时间: 2012
• 期刊: Tuberculosis (Edinburgh, Scotland)
• 作者: Ernst,JoelD;Hanekom,Willem;Hawn,Tom;Kampmann,Beate;Rengarajan,Jyothi
• 通讯作者: Rengarajan,Jyothi