Unique ADP-ribosylating and vacuolating properties of Mycoplasma pneumoniae CARDS toxin trigger airway inflammation and disease progression

肺炎支原体卡毒素独特的 ADP-核糖基化和空泡特性触发气道炎症和疾病进展

• 批准号: 9762435
• 负责人: Thirumalai Rengasamy Kannan
• 金额: $ 46.92万
• 依托单位: UNIVERSITY OF TEXAS HLTH SCIENCE CENTER
• 依托单位国家: 美国
• 财政年份: 2019
• 资助国家: 美国
• 起止时间: 2019-03-01 至 2024-02-29
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9762435
• 关键词: ADP Ribose Transferases; ADP ribosylation; Acute; Adult; Affect; Airway Disease; Allergic inflammation; Amino Acyl Transfer RNA; Annexins; Asthma; Bacterial Pneumonia; Binding; Carbon; Cell Degranulation; Cell Line; Cells; Characteristics; Child; Chronic; Chronic Obstructive Airway Disease; Communities; Community Acquired Respiratory Distress Syndrome Toxin; Complex; Cytopathology; Cytosol; Disease; Disease Progression; Dose; Elongation Factor; Exhibits; Functional disorder; Glycine Hydroxymethyltransferase; Histopathology; Human; IgE; Immune response; Infection; Inflammasome; Inflammation; Inflammatory; Inflammatory Response; Injury; Interleukin-1 beta; Intoxication; Knock-out; Knockout Mice; Lead; Lecithin; Length; Lower respiratory tract structure; Lung; Lung Inflammation; Lung diseases; Lymphocyte; Mediating; Membrane; Membrane Lipids; Metabolism; Metaplasia; Modality; Molecular; Mouse Cell Line; Mucous body substance; Mus; Mycoplasma pneumonia infection; Mycoplasma pneumoniae; N-terminal; Natural Immunity; Organ Culture Techniques; Organelles; Papio; Pathogenesis; Pathologic; Pathology; Pathway interactions; Peripheral Blood Mononuclear Cell; Personal Satisfaction; Phenotype; Phospholipids; Physiological; Play; Pneumonia; Primates; Process; Property; Proteins; Pulmonary Pathology; Pulmonary Surfactant-Associated Protein A; Respiration Disorders; Ribosomes; Rodent; Role; Severities; Shapes; Sphingomyelins; Structure of parenchyma of lung; Testing; Therapeutic; Therapeutic Intervention; Tissues; Toxin; United States; Vacuole; Wild Type Mouse; adaptive immunity; airway hyperresponsiveness; airway inflammation; airway remodeling; bacterial community; base; cytokine; eosinophil; eosinophilic inflammation; improved; in vivo; injured airway; macrophage; mast cell; microbial; mutant; novel; pathogen; protein 50 kDa; prototype; public health relevance; receptor; receptor binding; respiratory; respiratory distress syndrome; response

Abstract Mycoplasma pneumoniae is the leading cause of bacterial pneumonia in children hospitalized with community acquired pneumonia (CAP) and the second most common cause of bacterial CAP in adults in the United States. Persistent and recurring M. pneumoniae infection leads to severe respiratory disorders, including asthma and COPD, and a range of extrapulmonary pathologies. Until recently, it was unknown how a respiratory pathogen, like M. pneumoniae, induces cytopathology and exaggerated inflammatory responses that cause airway injury, dysfunction and remodeling. We identified a novel M. pneumoniae ADP- ribosylating and vacuolating toxin designated Community Acquired Respiratory Distress Syndrome (CARDS) toxin. CARDS toxin alone elicits the characteristic airway inflammation, lung histopathology, cellular vacuolation, mucus metaplasia and pulmonary dysfunction in intoxicated rodents and primates that are observed during infection with M. pneumoniae. The amino terminal domain of full length (FL) CARDS toxin (i.e., N-CARDS) retains ADP-ribosyltransferase (ART) activity. N-CARDS selectively ADP-ribosylates NLRP3 of the NLRP3 inflammasome complex, resulting in inflammasome activation and subsequent release of IL- 1β, a potent pro-inflammatory cytokine. In preliminary results, we also show that CARDS toxin selectively ADP-ribosylates serine hydroxymethyltransferase (SHMT2), which is involved in one carbon metabolism, and EF1γ, which is involved in the transfer of aminoacyl-tRNAs to the ribosome. The unique carboxyl region of FL CARDS toxin (i.e., C-CARDS) selectively binds to receptors surfactant protein-A (SP-A), annexin A2 (AnxA2) and phospholipids, phosphatidylcholine (PC) and sphingomyelin (SM). Internalization of FL CARDS toxin follows receptor-mediated binding, with subsequent ADP-ribosylation of host target proteins, vacuolation, hyperinflammation and cell/tissue histopathology and injury. Interestingly, C-CARDS alone causes both vacuole formation in human cells and eosinophilic inflammation in naïve mice, leading to an asthma-like phenotype. In this proposal, we intend to identify how ART and vacuolating properties of CARDS toxin trigger pro-inflammatory and pathologic responses in human WT, silenced or knockout cells and in WT and knockout mice. Based on our preliminary results, we hypothesize that both ADP-ribosylating and vacuolating activities contribute to the overall ability of CARDS toxin to initiate and sustain disease pathogenesis. We plan to test this hypothesis by – a) studying how CARDS toxin ART activities initiate inflammatory pathways and cytopathology, b) elucidating the role of receptor binding in CARDS toxin-mediated inflammation, c) characterizing how vacuolating activity promotes airway inflammation and injury, and d) analyzing the in vivo involvement of select ART and receptor targets in triggering CARDS toxin-mediated airway inflammation and lung pathology. Understanding the mechanisms by which ART and vacuolating activities of CARDS toxin regulate host response should lead to therapeutic interventions and improved societal well-being.

抽象的 肺炎支原体是住院儿童细菌性肺炎的主要原因 社区获得性肺炎 (CAP) 是成人细菌性 CAP 的第二常见原因 美国，持续且反复出现的肺炎支原体感染会导致严重的呼吸系统疾病， 包括哮喘和慢性阻塞性肺病，以及一系列肺外疾病，直到最近，人们还不知道它是如何发生的。 呼吸道病原体，如肺炎支原体，会引起细胞病理学和过度炎症 我们发现了一种新型肺炎支原体 ADP- 导致气道损伤、功能障碍和重塑的反应。 核糖基化和空泡毒素指定为社区获得性呼吸窘迫综合征 (CARDS) 卡毒素单独引起特征性气道炎症、肺组织病理学、细胞学。 中毒啮齿动物和灵长类动物中出现空泡形成、粘液化生和肺功能障碍 在肺炎支原体感染期间观察到全长（FL）卡毒素的氨基末端结构域。 （即 N-CARDS）保留 ADP-核糖基转移酶 (ART) 活性 N-CARDS 选择性 ADP-核糖基化 NLRP3。 NLRP3 炎症小体复合物的作用，导致炎症小体激活并随后释放 IL- 1β，一种有效的促炎细胞因子，在初步结果中，我们还表明 CARDS 毒素具有选择性。 ADP-核糖基丝氨酸羟甲基转移酶（SHMT2），参与一碳代谢，以及 EF1γ，参与酰氨基-tRNA 向核糖体的转移 FL 的独特羧基区域。 CARDS 毒素（即 C-CARDS）选择性结合受体表面活性剂蛋白-A (SP-A)、膜联蛋白 A2 (AnxA2) 以及磷脂、磷脂酰胆碱 (PC) 和鞘磷脂 (SM) 的 FL 卡毒素内化。 遵循受体介导的结合，随后宿主靶蛋白的 ADP 核糖基化、空泡化、 过度炎症和细胞/组织病理学和损伤提示，C-CARDS 单独导致这两种情况。 人类细胞中的真空形成和幼鼠中的嗜酸性粒细胞炎症，导致哮喘样症状 在本提案中，我们打算确定 ART 和卡毒素的空泡特性是如何触发的。 人类 WT、沉默或敲除细胞以及 WT 和 根据我们的初步结果，我们勇敢地进行了 ADP 核糖基化和空泡化。 活性有助于 CARDS 毒素启动和维持疾病发病机制的整体能力。 计划通过以下方式检验这一假设：a) 研究 CARDS 毒素 ART 活动如何启动炎症途径 和细胞病理学，b) 阐明受体结合在 CARDS 毒素介导的炎症中的作用，c) 描述空泡活动如何促进气道炎症和损伤，以及 d) 分析体内 选择 ART 和受体靶标参与触发 CARDS 毒素介导的气道炎症， 了解 ART 和 CARDS 毒素空泡活性的机制。 调节宿主反应应导致治疗干预和改善社会福祉。