Genetic Requirements for the survival of Tubercle Bacilli in Nonhuman Primates

非人灵长类结核杆菌生存的遗传要求

• 批准号: 8292918
• 负责人: Deepak Kaushal
• 金额: $ 78.3万
• 依托单位: TULANE UNIVERSITY OF LOUISIANA
• 依托单位国家: 美国
• 财政年份: 2010
• 资助国家: 美国
• 起止时间: 2010-06-01 至 2015-05-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8292918
• 关键词: Acquired Immunodeficiency Syndrome; Acute; Address; Aerosols; Age; Alveolar; Anabolism; Animals; Antitubercular Agents; Attenuated; Autopsy; Bacillus (bacterium); Belief; Biological Assay; Body Temperature; C-reactive protein; CCL19 gene; CCL2 gene; CCL7 gene; CD4 Positive T Lymphocytes; Catabolism; Cavia; Cell Wall; Cells; Cessation of life; Characteristics; Cholesterol; Chromosomes; Chronic; Clinical; Communicable Diseases; Confocal Microscopy; DNA Repair; Defect; Development; Disease; Dose; Drug resistance; Emergency Situation; Environment; Enzyme-Linked Immunosorbent Assay; Exhibits; Failure; Family; Fatty Acids; Genes; Genetic; Genome; Granuloma; Granulomatous; Growth; Health; Histopathology; Human; Hypersensitivity skin testing; Hypoxia; Immune system; In Situ Hybridization; Individual; Infection; Inflammatory; Interleukin-12; Irrigation; Lesion; Libraries; Liver; Lung; Lung Lavage Fluid; Macaca mulatta; Mammalian Cell; Measurement; Measures; Metabolism; Minority; Modeling; Monkeys; Mus; Mycobacterium tuberculosis; Nitrate Reductases; Nutrient; Operon; Output; Pathogenesis; Pathology; Pathway interactions; Peptidoglycan; Pharmaceutical Preparations; Phase; Phenotype; Phosphotransferases; Physiological; Play; Primates; Process; Production; Pulmonary Tuberculosis; Regulon; Relative (related person); Reporting; Resistance; Rest; Reverse Transcriptase Polymerase Chain Reaction; Role; Sampling; Serum; Simian Acquired Immunodeficiency Syndrome; Southern Blotting; Spleen; Staging; Sterols; Stress; System; Testing; Time; Tuberculosis; Tuberculosis Vaccines; Vaccines; Validation; Virulence; Virulence Factors; Virulent; Weight; araban; attenuation; base; hygromycin A; immune activation; immunopathology; in vivo; lipid transport; lymph nodes; macrophage; male; member; mortality; mouse model; mutant; nitrate reductase; nonhuman primate; peripheral blood; research study; response; sensor; transposon site hybridization; tuberculosis drugs; vector

DESCRIPTION (provided by applicant): Tuberculosis (TB), caused by Mycobacterium tuberculosis (Mtb), is a global infectious disease emergency. Each year an estimated 8 million people develop, and about two million people die of TB. Synergy with AIDS, the emergence of drug-resistance and the lack of effective anti-TB drugs and vaccines has worsened this situation. New drugs and vaccines are urgently needed to effectively control TB. This requires a better understanding of how Mtb adapts to a wide-variety of environmental conditions, inevitably faced by it during the various stages of infection. Nonhuman Primates (NHPs), arguably, best model critical aspects of TB. Analysis of the mechanisms employed by Mtb to successfully infect and persist in NHP lungs would therefore be very useful. We studied genes essential for growth/survival of Mtb in the NHP lungs experimentally exposed to high doses of aerosols of an Mtb transposon mutant library. In this acute model of TB, 33.13% of all tested mutants were attenuated for in-vivo growth compared to the mouse model where only ~6% of all mutants are attenuated. The Mtb mutants attenuated for in-vivo survival in primates were involved in the transport of lipid virulence factors; biosynthesis of cell-wall arabinan and peptidoglycan, fatty-acids and polyketides; DNA repair; sterol metabolism and mammalian cell-entry (mce). Our study highlights the various virulence-mechanisms employed by Mtb for infection and to overcome the hostile environment encountered during infection of NHP lungs. We would like to leverage our ability to model the various clinical phases of human TB - acute, pulmonary TB, chronic-progressive TB and latent, asymptomatic TB in NHPs - to study the growth/survival phenotype profiles of Mtb mutants. Further, we would like to better understand the role of two Mtb pathways crucial for virulence and pathogenesis, using the NHP model. These include the mce1/mce4 operons, whose members were among mutants that were attenuated for growth in NHP lungs; and members of the dos regulon, which were surprisingly not attenuated in NHP lungs, in-spite of their well-defined roles in latency, persistence and defense against hypoxia. PUBLIC HEALTH RELEVANCE: Tuberculosis (TB) is a global emergency, responsible for the death of an estimated 2 million people annually. Monkeys, due to their genetic and physiological similarities to humans, are a very good animal system to model TB. Out of the several hundreds of genes present in the chromosome of the tubercle bacillus, we have determined which ones are needed to establish a successful infection in the lungs of monkeys. These results will be compared to those obtained from animals with TB/AIDS co-infection. Genes from the mce (mammalian cell entry) family were among those which were attenuated in the NHP lungs. We will perform functional studies using Mycobacterium tuberculosis (Mtb) and defined mutants in mce genes, using our monkey model, to better understand their role in disease process.

描述（由申请人提供）：结核病（TB）由结核分枝杆菌（Mtb）引起，是一种全球性传染病紧急情况。据估计，每年有 800 万人罹患结核病，约 200 万人死于结核病。与艾滋病的协同作用、耐药性的出现以及有效抗结核药物和疫苗的缺乏使这种情况更加恶化。迫切需要新药和疫苗来有效控制结核病。这需要更好地了解结核分枝杆菌如何适应各种环境条件，这是它在感染的各个阶段不可避免地要面对的。非人类灵长类动物 (NHP) 可以说是结核病关键方面的最佳模型。因此，分析 Mtb 成功感染 NHP 肺部并在其中持续存在的机制将非常有用。我们研究了 NHP 肺中 Mtb 生长/生存所必需的基因，该肺通过实验暴露于 Mtb 转座子突变体库的高剂量气溶胶。在这种结核病急性模型中，所有测试的突变体中有 33.13% 的体内生长被减毒，而小鼠模型中只有约 6% 的突变体被减毒。灵长类动物体内存活能力减弱的 Mtb 突变体参与脂质毒力因子的转运；细胞壁阿拉伯聚糖和肽聚糖、脂肪酸和聚酮化合物的生物合成； DNA修复；甾醇代谢和哺乳动物细胞进入（MCE）。我们的研究强调了 Mtb 用于感染和克服 NHP 肺部感染期间遇到的恶劣环境的各种毒力机制。我们希望利用我们对人类结核病各个临床阶段（急性、肺结核、慢性进行性结核病和 NHP 中潜伏、无症状结核病）进行建模的能力，来研究 Mtb 突变体的生长/生存表型概况。此外，我们希望使用 NHP 模型更好地了解对毒力和发病机制至关重要的两条 Mtb 途径的作用。其中包括 mce1/mce4 操纵子，其成员属于在 NHP 肺中生长减弱的突变体；令人惊讶的是，尽管它们在潜伏期、持久性和防御缺氧方面具有明确的作用，但它们在 NHP 肺部中却没有减弱。 公共卫生相关性：结核病 (TB) 是一种全球性紧急情况，每年造成约 200 万人死亡。由于猴子在遗传和生理上与人类相似，因此是模拟结核病的非常好的动物系统。在结核杆菌染色体中存在的数百个基因中，我们已经确定了在猴子肺部成功感染所需的哪些基因。这些结果将与从结核病/艾滋病合并感染的动物中获得的结果进行比较。来自 mce（哺乳动物细胞进入）家族的基因在 NHP 肺部中被减弱。我们将使用结核分枝杆菌 (Mtb) 和 mce 基因中定义的突变体，使用我们的猴子模型进行功能研究，以更好地了解它们在疾病过程中的作用。