Non-canonical NLRP3 Inflammasome Activation in Geographic Atrophy

地图样萎缩中的非典型 NLRP3 炎症小体激活

• 批准号: 9193873
• 负责人: Nagaraj Kerur
• 金额: $ 2.26万
• 依托单位: UNIVERSITY OF KENTUCKY
• 依托单位国家: 美国
• 财政年份: 2016
• 资助国家: 美国
• 起止时间: 2016-01-01 至 2016-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9193873
• 关键词: Advisory Committees; Age related macular degeneration; Atrophic; Blindness; CASP1 gene; Caspase; Cell Culture Techniques; Cell Death; Cells; Cellular biology; Cessation of life; DICER1 gene; Dependency; Development; Disease; Educational workshop; Environment; Etiology; Eye; Faculty; Foundations; Goals; Grant; Health; Human; IL18 gene; Immune; Interferons; Interleukin-1; Interleukin-18; Investigation; Kentucky; Laboratories; Massachusetts; Measures; Mediating; Mentors; Modeling; Molecular; Monitor; Mus; Nature; Ophthalmology; Pathogenesis; Pathologic; Pathway interactions; Phase; Pilot Projects; Play; Proteomics; RNA; Regulation; Regulatory Pathway; Research; Research Personnel; Resources; Role; Scaffolding Protein; Signal Pathway; Signal Transduction; Structure of retinal pigment epithelium; Supervision; Therapeutic; Tissue Model; Training Activity; Transcript; Universities; Vision research; Work; Writing; age related; career; cytokine; geographic atrophy; human tissue; insight; macula; medical schools; member; mouse model; new therapeutic target; novel; programs; skills; vision science

DESCRIPTION (provided by applicant): This K99/R00 grant will facilitate the applicant's (Dr. Nagaraj Kerur) long-term goal to develop as an independent investigator in vision research. Geographic atrophy (GA) is an advanced form of age-related macular degeneration (AMD) characterized by central loss of vision due to retinal pigmented epithelium (RPE) degeneration. Currently there is no therapy available for GA because of its unclear etiology. We recently discovered that DICER1 deficit causes a pathologic accumulation of Alu RNA transcripts in the RPE of human GA eyes and that the accumulated Alu RNAs activate the NLRP3 inflammasome, which in turn leads to IL- 18/MyD88-dependent RPE cell death (Kaneko et al., Nature 2011; Tarallo et al., Cell 2012). In exciting, new preliminary studies we have discovered that Alu RNA-induced NLRP3 inflammasome activation occurs in a non-canonical fashion- a newly described pathway in which caspase 4 (aka caspase 11 in mouse) is required for the NLRP3 inflammasome activation (in contrast the canonical inflammasome activation is independent of caspase 4). The central goal of the proposed research is to define role of caspase 4-mediated non-canonical NLRP3 inflammasome activation in the context of GA and to identify critical signaling pathways regulating caspase 4 activation via the following aims: (1) Define the signaling pathways that regulate caspase 4 (aka caspase 11 in mouse) activation by Alu RNA; (2) Elucidate the mechanisms of caspase 4 (aka caspase 11 in mouse) activation of the NLRP3 inflammasome; and (3) Measure the activation of these non-canonical inflammasome signaling pathways in human GA. These studies will illuminate the molecular foundation of GA, unravel novel regulatory checkpoints of NLRP3 inflammasome activation, and provide a strong molecular foundation for exploiting new therapeutic targets in AMD. During the mentored phase, (K99) the applicant will carry out the proposed studies under direct supervision of the mentor Dr. Jayakrishna Ambati at the University of Kentucky. In addition, an advisory committee consisting of co-mentor, Dr. Katherine Fitzgerald and the faculty members at the Department of Ophthalmology and Visual Sciences will monitor the applicant's research progress and offer assistance in advancing the applicant's transition towards independent investigator. The Ambati Group at the University of Kentucky as well as the Fitzgerald Laboratory at the University of Massachusetts Medical School, both offer scientifically enriching environments and resources necessary for the advancement of the applicant's scientific career. The major focus of K99 phase will include: (1) mentored research to define molecular insights into the caspase 4 activation mechanism and to optimize experimental conditions for studies to be carried out in the R00 phase; and (2) training activities consisting of formal course work, seminars, workshops on grant writing and acquisition of other skill-sets required for successfully developing and leading an independent research program. During the R00 phase, the focus will be on: (1) deciphering the mechanisms by which caspase 4 regulates NLRP3 inflammasome activation; and (2) quantifying the activation of non-canonical inflammasome signaling pathways in human GA eyes. Overall this proposal will not only unravel the novel molecular mechanisms of RPE degeneration in GA, but will also equip the applicant with suitable skills to transition int an independent career in vision research.

描述（由申请人提供）：这项 K99/R00 资助将促进申请人（Nagaraj Kerur 博士）发展成为视觉研究独立研究者的长期目标。地理萎缩（GA）是年龄相关性黄斑变性（AMD）的一种晚期形式，其特征是由于视网膜色素上皮（RPE）变性导致中央视力丧失。由于 GA 的病因尚不清楚，目前尚无可用的治疗方法。我们最近发现 DICER1 缺陷会导致人 GA 眼 RPE 中 Alu RNA 转录本的病理性积累，并且积累的 Alu RNA 会激活 NLRP3 炎症小体，进而导致 IL-18/MyD88 依赖性 RPE 细胞死亡（Kaneko 等）等人，《自然》2011；塔拉洛等人，《细胞》2012）。在令人兴奋的新初步研究中，我们发现 Alu RNA 诱导的 NLRP3 炎症小体激活以一种非典型方式发生，这是一种新描述的途径，其中 NLRP3 炎症小体激活需要 caspase 4（在小鼠中又称为 caspase 11）（相比之下）典型的炎症小体激活独立于 caspase 4)。本研究的中心目标是明确 GA 背景下 caspase 4 介导的非经典 NLRP3 炎症小体激活的作用，并通过以下目标确定调节 caspase 4 激活的关键信号通路：(1) 定义以下信号通路：通过 Alu RNA 调节 caspase 4（在小鼠中又称为 caspase 11）激活； （2）阐明caspase 4（小鼠中的caspase 11）激活NLRP3炎症小体的机制； (3) 测量人类 GA 中这些非典型炎症小体信号通路的激活。这些研究将阐明 GA 的分子基础，揭示 NLRP3 炎症小体激活的新调控检查点，并为开发 AMD 的新治疗靶点提供强大的分子基础。在指导阶段，（K99）申请人将在肯塔基大学导师 Jayakrishna Ambati 博士的直接监督下进行拟议的研究。此外，由共同导师凯瑟琳·菲茨杰拉德博士和眼科和视觉科学系的教员组成的咨询委员会将监督申请人的研究进展，并为促进申请人向独立研究者的过渡提供帮助。肯塔基大学的安巴蒂小组以及马萨诸塞大学医学院的菲茨杰拉德实验室都为申请人的科学事业的发展提供了丰富的科学环境和资源。 K99阶段的主要重点将包括：（1）指导研究，以定义对caspase 4激活机制的分子见解，并优化R00阶段研究的实验条件； (2) 培训活动，包括正式课程、研讨会、赠款写作讲习班以及获得成功开发和领导独立研究项目所需的其他技能。 R00阶段的重点将是：（1）破译caspase 4调节NLRP3炎症小体激活的机制； (2) 量化人类 GA 眼中非典型炎症小体信号通路的激活。总体而言，该提案不仅将揭示 GA 中 RPE 变性的新分子机制，而且还将为申请人提供适当的技能，以过渡到视觉研究的独立职业。