Mannose Receptor, miR-511-3p, and Macrophage Polarization in Asthma

哮喘中的甘露糖受体、miR-511-3p 和巨噬细胞极化

• 批准号: 9181798
• 负责人: Peisong Gao
• 金额: $ 25.55万
• 依托单位: JOHNS HOPKINS UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2016
• 资助国家: 美国
• 起止时间: 2016-06-23 至 2018-05-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9181798
• 关键词: Allergens; Allergic; Allergic inflammation; Antigen Receptors; Antigens; Asthma; Binding; Biological Assay; Biotin; Blood; Bone Marrow; Candidate Disease Gene; Cells; Clinical; Computer Simulation; Data Set; Development; Dictyoptera; Exposure to; Extrinsic asthma; Gene Expression; Gene Targeting; Genes; Hematopoietic; Human; Hypersensitivity; IL6 gene; Immune; Individual; Inflammation; Inflammatory; Interleukin-1 beta; Investigation; Knockout Mice; Lead; Lentivirus Vector; Life; Link; Luciferases; Lung; Lung Inflammation; Macrophage Activation; Mediating; Messenger RNA; MicroRNAs; Mus; NOS2A gene; Pathway interactions; Phenotype; Pilot Projects; Reporter; Risk; Role; Serum; Severities; Signal Transduction; Staging; Stem cells; Translations; Work; airway inflammation; asthmatic; asthmatic patient; cockroach allergen; cytokine; knock-down; macrophage; mannose receptor; monocyte; mouse model; new therapeutic target; novel; overexpression; programs; protective effect; receptor; receptor binding; research study; stem

ABSTRACT Allergen exposure early in life is a strong predictor for the development of allergic asthma. Particularly, exposure to cockroach allergen can lead to allergic sensitization and increase the risk of developing allergic asthma. During the pilot stage for this proposal we have made a substantive breakthrough in understanding an important link within the cockroach antigen-sensitization-asthma pathway. We have demonstrated that the mannose receptor (MRC1/CD206) provides an impressive protective function in cockroach allergen induced airway inflammation. Our recent pilot study suggests that deletion of MRC1 in mice exacerbates cockroach allergen-induced lung inflammation, along with a tendency to polarize macrophages toward a M1 macrophage (inflammatory) phenotype. This finding was at first perplexing because MRC1 lacks a traditional signaling motif, therefore, the mechanisms underlying MRC1 mediated macrophage polarization and allergen induced lung inflammation remained obscure. Our breakthrough for a deeper understanding of this pathway came with the recognition of a key regulatory microRNA (miR-511-3p, the functional strand of miR-511). The miR-511-3p is encoded within the MRC1 gene and transcriptionally co-regulated in macrophages. This proposal centers on our novel hypothesis that the impressive protective effect of the mannose receptor on allergen-induced macrophage polarization and lung inflammation is due to the regulatory influences of miR-511-3p. Indeed, we have found that miR-511-3p was significantly lower in the blood of asthmatics compared to non-asthmatics, miR-511-3p is significantly increased in lung macrophages from cockroach extract-challenged mice, miR-511-3p is significantly reduced in bone marrow derived macrophages (BMDMs) lacking the MRC1, and BMDMs over-expressing miR-511-3p tend to polarize toward a M2 phenotype. These exciting data set the stage to critically evaluate the functional significance of miR-511-3p in MRC1-mediated macrophage polarization and allergen-induced allergic inflammation. Aim 1 proposes studies to detect the levels of miR-511-3p in serum and monocyte-derived macrophages and analyze their associations with allergic asthma, particularly those with cockroach allergy. Aim 2 proposes experiments to determine the role of miR-511-3p in MRC1-mediated macrophage polarization by over- or knockdown-expressing miR-511-3p in macrophages and in allergen-induced lung inflammation by generating bone-marrow chimeric mice with hematopoietic stem/progenitor cells (HS/PCs) miR-511-3p over- expression or knock-down and by using miR-511 mimic treatment. Aim 3 proposes experiments to identify the potential targets for miR-511-3p by using miR-511-3p overexpression or inhibition experiments, luciferase reporter and biotin pulldown assays. Together, this work will provide a framework to understand miRNA targets, and will lead to subsequent studies to probe the mechanisms underlying the MRC1/miR-511-3p-modulated macrophage activation and allergic inflammation with a focus on these identified targets. The study may ultimately offer an opportunity for the discovery of novel therapeutic targets for allergic asthma.

抽象的 生命早期过敏原暴露是过敏性哮喘发展的有力预测指标。特别是曝光 蟑螂过敏原会导致过敏敏化，并增加出现过敏性哮喘的风险。期间 该提案的试点阶段，我们在理解重要链接方面取得了实质性的突破 在蟑螂抗原 - 敏化 - 哮喘途径中。我们已经证明了甘露糖受体 （MRC1/CD206）在蟑螂过敏原引起的气道炎症中提供了令人印象深刻的保护功能。 我们最近的试点研究表明，小鼠中MRC1的删除加剧了蟑螂诱导的肺 炎症，以及倾向巨噬细胞向M1巨噬细胞两极的趋势（炎症） 表型。最初，这一发现是令人困惑的，因为MRC1缺乏传统的信号基准，因此， MRC1介导的巨噬细胞极化和过敏原诱导肺部炎症的机制 仍然晦涩难懂。我们深入了解这一途径的突破是认识到 关键调节microRNA（miR-511-3p，miR-511的功能链）。 miR-511-3p在 MRC1基因和转录在巨噬细胞中共同调节。该提议以我们的新假设为中心 甘露糖受体对过敏原诱导的巨噬细胞极化和 肺部炎症是由于miR-511-3p的调节影响。确实，我们发现mir-511-3p 与非asthmatics相比，哮喘患者的血液显着低，miR-511-3p显着 蟑螂提取物挑战小鼠的肺巨噬细胞增加，miR-511-3p显着降低 骨髓衍生的巨噬细胞（BMDMS）缺乏MRC1，而BMDM过表达miR-511-3p趋于 向M2表型偏振。这些令人兴奋的数据设定了批判性评估功能的舞台 miR-511-3p在MRC1介导的巨噬细胞极化和过敏原过敏性中的重要性 炎。 AIM 1提出的研究以检测血清和单核细胞中miR-511-3p的水平 巨噬细胞和分析其与过敏性哮喘的关联，尤其是那些患有蟑螂过敏的哮喘。目的 2提出了实验，以确定miR-511-3p在MRC1介导的巨噬细胞极化中的作用 巨噬细胞中表达miR-511-3p或过敏原诱导的肺部炎症的miR-511-3p 用造血茎/祖细胞（HS/PC）生成骨髓嵌合小鼠mir-511-3p过度 表达或敲除，并使用miR-511模拟处理。 AIM 3提出了实验以识别 通过使用miR-511-3p过表达或抑制实验，荧光素酶，miR-511-3p的潜在靶标 记者和生物素下拉分析。这项工作将提供一个框架来了解miRNA目标， 并将导致随后的研究以探测MRC1/miR-511-3p调制的机制 巨噬细胞激活和过敏性炎症，重点是这些鉴定靶标。研究可能 最终为发现过敏性哮喘的新型治疗靶标提供了机会。