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: 9323160
• 负责人: Nagaraj Kerur
• 金额: $ 22.64万
• 依托单位: UNIVERSITY OF VIRGINIA
• 依托单位国家: 美国
• 财政年份: 2016
• 资助国家: 美国
• 起止时间: 2016-09-01 至 2018-12-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9323160
• 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/R 00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。地图状萎缩（GA）是年龄相关性黄斑变性（AMD）的一种晚期形式，其特征在于由于视网膜色素上皮（RPE）变性导致的中心视力丧失。由于其病因不明，目前尚无治疗GA的方法。我们最近发现，DICER 1缺陷导致Alu RNA转录物在人GA眼睛的RPE中的病理性积累，并且积累的Alu RNA激活NLRP 3炎性体，这进而导致IL- 18/MyD 88依赖性RPE细胞死亡（Kaneko et al.，Nature 2011; Tarallo等人，Cell 2012）。在令人兴奋的新的初步研究中，我们发现Alu RNA诱导的NLRP 3炎性小体活化以非典型的方式发生-一种新描述的途径，其中NLRP 3炎性小体活化需要半胱天冬酶4（在小鼠中称为半胱天冬酶11）（相反，典型的炎性小体活化独立于半胱天冬酶4）。本研究的主要目的是明确caspase 4介导的非经典NLRP 3炎性小体激活在GA中的作用，并通过以下目的确定调节caspase 4激活的关键信号通路：（1）确定调节caspase 4的信号通路（2）阐明caspase 4的作用机制（3）测量人GA中这些非典型炎性体信号传导途径的活化。这些研究将阐明GA的分子基础，揭示NLRP 3炎性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有力的分子基础。在指导阶段，（K99）申请人将在肯塔基州大学的导师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师组成的咨询委员会将监测申请人的研究进展，并提供协助，推动申请人向独立研究者过渡。肯塔基州大学的Ambati小组以及马萨诸塞州大学医学院的Fitzgerald实验室都为申请人的科学事业的发展提供了科学丰富的环境和必要的资源。K99阶段的主要重点将包括：（1）指导研究，以确定caspase 4激活机制的分子见解，并优化R 00阶段研究的实验条件;以及（2）培训活动，包括正式课程、研讨会、研讨会的赠款写作和收购所需的其他技能，成功地开发和领导一个独立的研究计划。在R 00阶段，重点将是：（1）破译caspase 4调节NLRP 3炎性体激活的机制;和（2）定量人类GA眼中非经典炎性体信号通路的激活。总的来说，这项提案不仅将揭示GA中RPE变性的新分子机制，而且还将为申请人提供合适的技能，以过渡到视觉研究的独立职业生涯。