Nrf2 regulation of alveolar macrophage immune responses in vivo to Mycobacterium tuberculosis

Nrf2 调节肺泡巨噬细胞对结核分枝杆菌的体内免疫反应

• 批准号: 10555299
• 负责人: Alissa Chen Rothchild
• 金额: $ 19.43万
• 依托单位: UNIVERSITY OF MASSACHUSETTS AMHERST
• 依托单位国家: 美国
• 财政年份: 2022
• 资助国家: 美国
• 起止时间: 2022-01-25 至 2023-12-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10555299
• 关键词: Acceleration; Address; Adult; Aerosols; Agonist; Alveolar Macrophages; Antibiotic Therapy; Antioxidants; Bacillus; Bacteria; Cause of Death; Cell Death; Cells; Cessation of life; Communicable Diseases; Containment; Deposition; Detection; Development; Disease Outcome; Disease Progression; Distal; Dose; Drug resistant Mycobacteria Tuberculosis; Equilibrium; Event; Failure; Flow Cytometry; Future; Gene Expression; Goals; Growth; Host Defense; Hour; Immune; Immune response; Immunity; Impairment; In Vitro; Infection; Infection Control; Infectious Agent; Inflammation; Inflammatory; Inflammatory Response; Knockout Mice; Length; Lentivirus; Lung; Lung diseases; Macrophage; Maintenance; Modeling; Mouse Strains; Mucous Membrane; Mus; Mycobacterium tuberculosis; Myelogenous; Myeloid Cells; Oropharyngeal; Outcome; Pathway interactions; Positioning Attribute; Protocols documentation; Pulmonary Inflammation; Reagent; Regulation; Reporter; Reporting; Risk; Role; Sentinel; Sorting; System; Time; Tissues; Toxic effect; Treatment Protocols; Tuberculosis; Tuberculosis Vaccines; Vaccine Design; antimicrobial; cell type; conditional knockout; draining lymph node; immunopathology; immunoregulation; improved; in vivo; inhibitor; mouse model; prevent; programs; recruit; respiratory; response; small hairpin RNA; systemic inflammatory response; tool; transcription factor; transcriptome sequencing; transmission process; vaccine strategy

PROJECT SUMMARY Mycobacterium tuberculosis (Mtb) claims nearly 1.5 million lives each year and is one of the leading causes of death by an infectious agent worldwide. The lack of a protective TB vaccine for adult pulmonary disease, the length and toxicity of current antibiotic treatment regimens, and the rise in Mtb drug resistance all strongly motivate the pursuit of new host-directed therapies and strategies for vaccine design. Alveolar macrophages are the first cells in the lung to be infected with Mtb following aerosol transmission, performing a critical role as Mtb innate sentinels in the airway. They must initiate the host response that will recruit other innate cells into the lung and transfer bacteria to cells that can carry it to the draining lymph node for efficient immune priming. As tissue- resident myeloid cells, alveolar macrophages also perform a critical homeostatic function, clearing debris from the airway without triggering pulmonary inflammation. It is unknown how alveolar macrophages balance their innate sensing and tissue maintenance duties, while any delay in the initiation of the host response to Mtb provides the bacteria with additional time to replicate unchecked. Our previous results showed that Mtb-infected alveolar macrophages up-regulate a cell-protective signature, dependent on the transcription factor Nrf2. This in vivo response is distinct from the canonical pro-inflammatory response previously reported for Mtb-infected macrophages in vitro indicating that new information that can be gained from this in vivo approach. Our results showed that in the absence of Nrf2, Mtb-infected alveolar macrophages are more activated, less viable, and demonstrate enhanced control of bacteria within the first 10 days of infection, yet it is unknown how Nrf2 regulation of alveolar macrophage function early during infection impacts the subsequent stages of disease progression. The goal of this proposal is to develop diverse tools to modulate alveolar macrophage Nrf2 expression in order to define how Nrf2 impacts the timing and quality of the immune events following bacterial deposition in the airway, which ultimately lead to either disease progression or bacterial containment. First, we will characterize Nrf2 regulation of alveolar macrophage cell death and bacterial dissemination using myeloid- specific Nrf2 conditional knock-out strains (Aim 1). Second, we will develop an ex vivo system to study how Nrf2 interferes with alveolar macrophage innate sensing pathways and an shRNA lentiviral oropharyngeal delivery system to transiently block alveolar macrophage Nrf2 expression in vivo, allowing us to avoid any confounding effects of Nrf2 during development (Aim 2). The studies are driven by the hypothesis that the induction of a cell- protective program by Nrf2 prevents alveolar macrophages from mounting a rapid and effective pro-inflammatory response to Mtb infection, leading to delays in subsequent immune events that impair the host from controlling infection. By developing new tools and reagents to study the role of alveolar macrophage-specific Nrf2 expression, we will gain a better understanding of the early events of Mtb infection in the lung and evaluate the potential of Nrf2 as a future target for host-directed therapy.

项目摘要 结核分枝杆菌（MTB）每年夺取近150万人的生命，是主要原因之一 全世界感染力的死亡。缺乏针对成人肺疾病的保护性结核病疫苗， 当前抗生素治疗方案的长度和毒性以及MTB耐药性的升高均强烈 激励人们追求新的宿主定向疗法和疫苗设计策略。肺泡巨噬细胞是 气溶胶传播后肺中的第一个被MTB感染的细胞，作为MTB的关键作用 气道中的先天哨兵。他们必须发起宿主反应，将其他先天细胞招募到肺部 并将细菌转移到可以将其携带到排水淋巴结的细胞中，以进行有效的免疫启动。如组织 常驻髓样细胞，肺泡巨噬细胞也执行关键的稳态功能，清除了从 气道无触发肺部炎症。肺泡巨噬细胞如何平衡他们的 天生的感应和组织维护职责，而主机对MTB的响应的启动延迟 为细菌提供了额外的时间来复制不受限制的。我们先前的结果表明MTB感染了 肺泡巨噬细胞上调了细胞保护特征，取决于转录因子NRF2。这是 体内反应与先前报道的MTB感染的规范促炎反应不同 体外巨噬细胞表明可以从这种体内方法中获得的新信息。我们的结果 表明，在没有NRF2的情况下，MTB感染的肺泡巨噬细胞更加激活，较少，并且 在感染的前10天内证明了对细菌的控制增强，但尚不清楚NRF2 肺泡巨噬细胞功能早期感染期间的调节会影响疾病的随后阶段 进展。该建议的目的是开发各种工具来调节肺泡巨噬细胞NRF2 表达以定义NRF2如何影响细菌后免疫事件的时间和质量 气道沉积，最终导致疾病进展或细菌遏制。首先，我们 将表征NRF2调节肺泡巨噬细胞死亡和使用髓样的细菌传播 特定的NRF2条件敲除菌株（AIM 1）。其次，我们将开发一个离体系统来研究NRF2 干扰肺泡巨噬细胞的先天传感途径和shRNA慢病毒口咽递送 在体内瞬时阻断肺泡巨噬细胞NRF2表达的系统，使我们避免任何混淆 NRF2在开发过程中的影响（AIM 2）。研究是由诱导细胞的假设驱动的 NRF2保护程序可防止肺泡巨噬细胞安装快速有效的促炎性 对MTB感染的反应，导致随后损害宿主控制的免疫事件的延迟 感染。通过开发新工具和试剂来研究肺泡特异性NRF2的作用 表达，我们将更好地了解肺中MTB感染的早期事件并评估 NRF2作为宿主定向治疗的未来目标。