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: 9882954
• 负责人: Thirumalai Rengasamy Kannan
• 金额: $ 45.61万
• 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/9882954
• 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; tissue injury

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 支原体肺炎是住院儿童细菌肺炎的主要原因 社区获得了肺炎（CAP），也是成年人中第二大的细菌帽原因 美国。持续和反复发生的肺炎开发症会导致严重的呼吸系统疾病， 包括哮喘和COPD，以及一系列肺外病理。直到最近，还不知道 呼吸道病原体（如肺炎开发菌）诱导细胞病理学和夸张的炎症性 导致气道受伤，功能障碍和重塑的反应。我们确定了一种新颖的肺炎疟原虫ADP- 核糖基化和空泡毒素指定社区获得的呼吸窘迫综合征（卡） 毒素。仅卡毒素就会引起典型的气道注射，肺组织病理学，细胞 醉酒啮齿动物和私人的空泡，粘液化生和肺功能障碍 在感染肺炎支原体时观察到。全长（FL）卡毒素的氨基终端域 （即N卡）保留ADP-核糖基转移酶（ART）活性。 N-CARDS选择性ADP-ribosylates NLRP3 NLRP3炎性体复合物的膜，导致炎症体激活和随后释放IL- 1β，一种潜在的促炎细胞因子。在初步的结果中，我们还表明毒素有选择地 ADP-核苷酸盐丝氨酸羟基转移酶（SHMT2），参与一种碳代谢，并且 EF1γ参与了将氨基酰基 - trnas转移至核糖体的转移。 FL的独特羧基区域 卡毒素（即C卡）有选择地结合受体表面活性剂蛋白A（SP-A），膜联蛋白A2（Anxa2） 和磷脂，磷脂酰胆碱（PC）和鞘磷脂（SM）。 FL卡毒素的内在化 遵循受体介导的结合，随后宿主靶蛋白的ADP-核糖化，真空化， 高炎症和细胞/组织组织病理学和损伤。有趣的是，仅C卡就会引起两者 幼稚小鼠的人类细胞和嗜酸性粒细胞感染中的真空素形成，导致哮喘状 表型。在此提案中，我们打算确定毒素触发的艺术和吸水性能如何 人WT中的促炎和病理反应，沉默或基因敲除细胞以及WT和 淘汰老鼠。基于我们的初步结果，我们假设ADP-核糖基和空泡 活动有助于毒素启动和维持疾病发病机理的整体能力。我们 计划通过 - ） - ）研究卡毒素艺术活动如何启动炎症途径 和细胞病理学，b）阐明受体结合在卡片毒素介导的注射中的作用，c） 表征液泡活性如何促进气道感染和损伤，d）分析体内 将精选艺术和接收器目标参与触发卡片毒素介导的气道注入和 肺病理学。了解毒素毒素的艺术和液泡活动的机制 规范宿主的反应应导致治疗干预措施并改善社会福祉。