Innate inflammatory responses during pulmonary infections

肺部感染期间的先天炎症反应

• 批准号: 10272218
• 负责人: Katrin Mayer-Barber
• 金额: $ 129.37万
• 依托单位: NATIONAL INSTITUTE OF ALLERGY AND INFECTIOUS DISEASES
• 依托单位国家: 美国
• 资助国家: 美国
• 起止时间: 至
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10272218
• 关键词: Address; Adipose tissue; Aerosols; Animal Model; Animals; Antibodies; Area; Asthma; Autoimmune Diseases; Bacterial Infections; Biological; Biological Process; Blood specimen; Bone Marrow; Cations; Cell Communication; Cell Death; Cells; Chinese People; Chronic; Chronic Disease; Clinical Research; Cryptococcus; Cytoplasmic Granules; Data; Development; Dinoprostone; Disease; Dose; Effector Cell; Eicosanoids; Eotaxin; Exhibits; Fibroblasts; Fibrosis; Flow Cytometry; Goals; Helminths; Host resistance; Human; Hypersensitivity; IL8 gene; Immune response; Immunity; Immunologic Techniques; Immunologics; Immunotherapy; Individual; Infection; Inflammation; Inflammatory; Inflammatory Response; Influenza A virus; Innate Immune Response; Interferon Type I; Interferons; Interleukin-1; Interleukin-6; Investigation; Lead; Leukotrienes; Light; Lipids; Lung; Lung infections; Macaca; Macaca mulatta; Maintenance; Malignant Neoplasms; Measures; Mediating; Messenger RNA; Modeling; Mouse Strains; Mus; Mycobacterium avium; Mycobacterium tuberculosis; Mycoses; Myelogenous; Nature; Outcome; Pathology; Pathway interactions; Patients; Phagocytes; Physiological; Plasma Cells; Play; Predisposition; Primary Infection; Process; Prospective cohort; Prostaglandins; Proteins; Published Comment; Reactive Oxygen Species; Regulation; Research; Resected; Respiratory Tract Infections; Role; Stains; Surface; System; TNF gene; Time; Tissues; Tuberculosis; Vaccine Design; Vaccines; Viral; Whole Blood; adaptive immunity; antimicrobial; arm; autoinflammatory; bactericide; chemokine; chronic infection; cytokine; cytotoxic; eosinophil; granulocyte; immunoregulation; in vivo; insight; lipid mediator; macrophage; migration; mouse model; neutrophil; non-tuberculosis mycobacteria; novel; programs; respiratory; response; translational pipeline; treatment strategy; wound healing

The development of effective vaccines and host directed therapies (HDT) against M. tuberculosis (Mtb) infection requires a detailed understanding of the cellular basis of protective immunity. Considerable progress has been made in our understanding of protective adaptive immunity, yet relatively little is known about the contribution of innate effector cells. Particularly, the biological relevance of granulocytes like neutrophils and eosinophils is poorly understood. The innate inflammatory response is a prime target for HDT and manipulation of granulocytes could have major inflammatory and immunoregulatory implications for host resistance. Recent advances in vaccine design were highlighted by our group through an invited commentary in Immunity. Similar to neutrophils, eosinophils are phagocytic cells of the myeloid lineage that are thought to play an important effector role in the innate immune response. Their lineage-specific secondary granules contain cytotoxic cationic granular proteins (ECP, EDN, MBP and EPO) that have been shown to exhibit anti-microbial activity and cause tissue damage. Preformed cytokines contained in these same granules include inflammatory cytokines like TNF-, IL-1, IL-6 and IL-8 and pro-fibrogenic cytokines that can stimulate fibroblast proliferation, fibrotic and wound healing responses. In addition, lipid bodies, which form in response to eosinophil activation, contain a wide variety of leukotrienes, prostaglandins and reactive oxygen species that can contribute to these processes. More recently, eosinophils have been shown to play an important role in immunoregulation and homeostatic functions, including maintenance of long-lived plasma cells in the bone marrow and alternatively activated macrophages in adipose tissue. Eosinophils and their biological functions of have been studied primarily in the context of type 2 immunity, including parasitic helminth and pulmonary fungal infection, allergies and asthma. The role of eosinophils during bacterial infection remains largely unexplored. However, a comprehensive study on the role of eosinophils during Mtb infection is lacking, both in animal models as well human clinical studies. Another barrier to our understanding of eosinophils in host resistance to TB is a paucity of data from the mouse model of Mtb infection. There are likely two major contributing factors to be considered for this: 1) Mtb infection primarily causes a type I immune response, and eosinophils are rare in numbers compared to neutrophils in the lungs of Mtb infected mice (KDMB unpublished data) and 2) the pathology of Mtb infected mouse lungs and human lungs is vastly different. Eosinophils were found to be enriched in areas of tissue remodeling and fibrosis in TB resected lungs from patients (KDMB unpublished data). While fibrotic responses are often seen in TB patients, they are not considered a feature in the mouse model of Mtb infection. Indeed, the physiological role and function of eosinophils in type 1 immune responses to intracellular bacterial infections remains unknown. Here, in exploring the pulmonary granulocytic response to Mtb infection across species, we discovered that eosinophils migrated rapidly to Mtb-infected lungs. Because surface antibodies used to identify human eosinophils did not cross-react with eosinophils from rhesus macaques, we developed a strategy to quantify eosinophil responses in macaques by flow cytometry. We found that intracellular staining with EPX selectively and specifically stains eosinophils in both NHP and human whole blood samples and demonstrated that eosinophils rapidly migrate into Mtb infected rhesus macaque airways. We also identified eosinophils as the first cells sensing and repsondong to Mtb infection in the mouse lung after Mtb infection. Importantly, eosinophil deficient mouse strains demonstrated increased susceptibility to disease, with significantly reduced survival times. We also examined the chemokines responsible for eosinophil migration during tuberculosis and found that CCR3-mediated recognition of eotaxins were dispensible for tissue migration. We have previously characterized two major innate cytokine pathways, IL-1 and type I interferons, respectively, that play pivotal roles in governing host resistance versus disease in the murine model of Mtb infection by intersecting the eicosanoid lipid network. In particular, we uncovered that IL-1 can in turn counter-regulate type I IFN driven detrimental responses during Mtb infection. In murine and human macrophages IL-1 and IL-1 potently inhibit type I IFN induction at both the mRNA and protein level and similarly IFN mRNA and protein levels are upregulated in the lungs of Mtb infected Il1r1-/- deficient mice. This inhibition is of functional importance because mice doubly deficient in Il1r1,Ifnar1-/- are partially protected while Il1r1-/- singly deficient animals succumb rapidly to Mtb aerosol challenge. Moreover, when IL-1 is present in type I IFN treated cultures, it even suppresses the pro-bacterial effects downstream of IFN that lead to increased bacterial replication. Interestingly, IL-1 induced PGE2 is also able to potently inhibit type I IFNs in a dose dependent manner. These data highlighted and provided proof-of-concept that the cross-talk of IL-1 and type I IFN provides a valuable target for host-directed therapies of Mtb and plays a major role during infection in mice. Moreover, we measured and analyzed cytokines, chemokines, and lipid mediators of the IL-1, type IFN and eicosanoid axis in a prospective cohort of Chinese individuals infected with M. tuberculosis. We are currently investigating the exact nature of IL-1 and type I IFN induced cell death mechanisms, lipid regulation and host resistance pathways during tuberculosis.

针对结核分枝杆菌 (Mtb) 感染的有效疫苗和宿主定向疗法 (HDT) 的开发需要详细了解保护性免疫的细胞基础。我们对保护性适应性免疫的理解已经取得了相当大的进展，但对先天效应细胞的贡献知之甚少。特别是，对中性粒细胞和嗜酸性粒细胞等粒细胞的生物学相关性知之甚少。先天炎症反应是 HDT 的主要目标，粒细胞的操纵可能对宿主抵抗产生重大炎症和免疫调节影响。我们的小组通过《免疫》杂志的特邀评论强调了疫苗设计的最新进展。 与中性粒细胞类似，嗜酸性粒细胞是骨髓谱系的吞噬细胞，被认为在先天免疫反应中发挥重要的效应作用。它们的谱系特异性次级颗粒含有细胞毒性阳离子颗粒蛋白（ECP、EDN、MBP 和 EPO），这些蛋白已被证明具有抗微生物活性并导致组织损伤。这些相同颗粒中含有的预先形成的细胞因子包括炎症细胞因子，如 TNF-、IL-1、IL-6 和 IL-8，以及促纤维细胞因子，可刺激成纤维细胞增殖、纤维化和伤口愈合反应。此外，响应嗜酸性粒细胞活化而形成的脂质体含有多种白三烯、前列腺素和活性氧，它们可以促进这些过程。最近，嗜酸性粒细胞已被证明在免疫调节和稳态功能中发挥重要作用，包括维持骨髓中的长寿命浆细胞和脂肪组织中替代性活化的巨噬细胞。嗜酸性粒细胞及其生物学功能主要在 2 型免疫的背景下进行研究，包括寄生虫和肺部真菌感染、过敏和哮喘。嗜酸性粒细胞在细菌感染过程中的作用在很大程度上仍未被探索。然而，无论是在动物模型还是人类临床研究中，都缺乏对嗜酸性粒细胞在结核分枝杆菌感染过程中的作用的全面研究。我们了解嗜酸性粒细胞在宿主对结核病抵抗中的作用的另一个障碍是缺乏来自结核分枝杆菌感染小鼠模型的数据。对此可能有两个主要影响因素：1) Mtb 感染主要引起 I 型免疫反应，与 Mtb 感染小鼠肺部的中性粒细胞相比，嗜酸性粒细胞的数量很少（KDMB 未发表的数据），2)感染 Mtb 的小鼠肺部和人类肺部的病理学有很大不同。研究发现，结核病患者肺切除后的组织重塑和纤维化区域中嗜酸性粒细胞富集（KDMB 未发表的数据）。虽然纤维化反应常见于结核病患者，但它们并不被认为是结核分枝杆菌感染小鼠模型的特征。事实上，嗜酸性粒细胞在针对细胞内细菌感染的 1 型免疫反应中的生理作用和功能仍然未知。在这里，在探索不同物种的肺粒细胞对 Mtb 感染的反应时，我们发现嗜酸性粒细胞迅速迁移到 Mtb 感染的肺部。由于用于识别人类嗜酸性粒细胞的表面抗体不会与恒河猴的嗜酸性粒细胞发生交叉反应，因此我们开发了一种通过流式细胞术量化猕猴中嗜酸性粒细胞反应的策略。我们发现，EPX 的细胞内染色选择性地、特异性地对 NHP 和人全血样本中的嗜酸性粒细胞进行染色，并证明嗜酸性粒细胞快速迁移到 Mtb 感染的恒河猴气道中。我们还鉴定出嗜酸性粒细胞是小鼠肺部感染 Mtb 后第一个感知和响应 Mtb 感染的细胞。重要的是，嗜酸性粒细胞缺陷的小鼠品系表现出对疾病的易感性增加，并且存活时间显着缩短。我们还检查了结核病期间负责嗜酸性粒细胞迁移的趋化因子，发现 CCR3 介导的嗜酸性粒细胞趋化因子识别对于组织迁移来说是可有可无的。 我们之前已经描述了两种主要的先天细胞因子途径，分别是 IL-1 和 I 型干扰素，它们通过与类二十烷酸脂质网络相交，在 Mtb 感染的小鼠模型中在控制宿主抵抗力与疾病方面发挥着关键作用。特别是，我们发现 IL-1 可以反过来调节 Mtb 感染期间 I 型 IFN 驱动的有害反应。在小鼠和人类巨噬细胞中，IL-1 和 IL-1 在 mRNA 和蛋白质水平上有效抑制 I 型 IFN 诱导，类似地，在 Mtb 感染的 Il1r1-/- 缺陷小鼠的肺部，IFN mRNA 和蛋白质水平上调。这种抑制具有重要的功能性，因为双重缺乏 Il1r1、Ifnar1-/- 的小鼠受到部分保护，而单一缺乏 Il1r1-/- 的小鼠会迅速死于 Mtb 气溶胶攻击。此外，当 I 型 IFN 处理的培养物中存在 IL-1 时，它甚至会抑制 IFN 下游的亲细菌作用，从而导致细菌复制增加。有趣的是，IL-1 诱导的 PGE2 也能够以剂量依赖性方式有效抑制 I 型 IFN。这些数据强调并提供了概念证明，即 IL-1 和 I 型 IFN 的串扰为 Mtb 的宿主定向治疗提供了有价值的靶标，并在小鼠感染过程中发挥着重要作用。 此外，我们在感染结核分枝杆菌的中国个体前瞻性队列中测量并分析了 IL-1、IFN 型和类二十烷酸轴的细胞因子、趋化因子和脂质介质。我们目前正在研究结核病期间 IL-1 和 I 型 IFN 诱导的细胞死亡机制、脂质调节和宿主抵抗途径的确切性质。