Mechanistically defining the role for each NFkB family member in pro-inflammatory macrophage activation

从机制上定义每个 NFkB 家族成员在促炎巨噬细胞激活中的作用

• 批准号: 10315871
• 负责人: Allison E Daly
• 金额: $ 4.05万
• 依托单位: UNIVERSITY OF CALIFORNIA LOS ANGELES
• 依托单位国家: 美国
• 财政年份: 2021
• 资助国家: 美国
• 起止时间: 2021-09-01 至 2023-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10315871
• 关键词: 2019-nCoV; Adult Respiratory Distress Syndrome; Affinity; Bacterial Infections; Binding; Binding Sites; Biochemical; Biological; Biological Models; Biological Process; Bone Marrow; COVID-19 patient; CRISPR/Cas technology; Cause of Death; Cells; Centers for Disease Control and Prevention (U.S.); Cessation of life; ChIP-seq; Chromatin; Clinical; Combinatorics; Complex; Country; Coupled; Data; Data Set; Dependence; Deterioration; Developing Countries; Disease; Escherichia coli; Event; Family; Family member; Gene Expression; Gene Expression Regulation; Genes; Genetic Transcription; Homo; Immune; Immune System Diseases; Immune system; In Vitro; Income; Individual; Infection; Inflammatory; LCN2 gene; Lead; Link; Logic; Macrophage Activation; Measures; Modeling; Molecular; Mutate; Nuclear; Organ; Pathogenesis; Pathogenicity; Pathology; Patients; Pattern recognition receptor; Peritoneal Macrophages; Phenotype; Pregnancy; Proteins; Regulation; Reproducibility; Research; Research Proposals; Role; Sepsis; Signal Transduction; Stimulus; System; TNFRSF5 gene; Transactivation; Viral; Virus; Virus Diseases; World Health Organization; cecal ligation puncture; cell behavior; chemokine; combinatorial; cytokine; dimer; genetic regulatory protein; genome-wide; immune activation; immunoregulation; in vivo; insight; macrophage; member; monomer; mortality; mouse model; novel; patient population; programs; response; systemic inflammatory response; therapeutic target; transcription factor; transcriptome; transcriptome sequencing

PROJECT SUMMARY The World Health Organization (WHO) estimates that ~6 million people die from sepsis each year, with the greatest burden felt in low to middle income countries. According to the WHO, one out of ten deaths during pregnancy is a result of maternal sepsis with over 95% of these cases arising in developing countries. Finally, the Centers for Disease Control and Prevention, estimates that 3-17% of all patients with COVID-19 will develop acute respiratory distress syndrome (ARDS), the primary cause of mortality in this patient population. Sepsis and ARDS, represent severe consequences of immune system overactivation and dysregulation during infection. Although the burden of this pathology is recognized, the molecular underpinnings of this clinical deterioration remain poorly understood. NFkB is a ubiquitous transcription factor that is activated during viral and bacterial infection to control innate immune cell behavior and is thus likely to be a key player in immune dysregulation. NFkB is a family of TFs containing 5 subunits (cRel, RelA, p50, p52, and RelB) that combinatorically interact to form 15 possible dimeric species to regulate gene expression. Although, NFkB is well studied, there remains a paucity of research investigating the function of individual NFkB dimers in immune cell activation. Preliminary analysis supports the central hypothesis that each dimer of NFkB has a unique biological function. Understanding the role of individual NFkB dimers could open avenues for the precise modulation of pro-inflammatory gene expression. Further, my data supports the hypothesis that cRel homodimers are necessary for the selective regulation of a small group of genes including Il12b; and p50 homodimers associate with a co-regulatory protein to activate key pro-inflammatory genes including Il6, Il1b and Lcn2. This research employs a bone marrow derived macrophage model system in combination with the extraction of primary peritoneal macrophages stimulated ex vivo with E. coli or in vivo with a cecal ligation and puncture model of sepsis, to define dimer specific roles of NFkB in macrophage activation and the molecular mechanisms underlying dimer specific gene regulation. This proposal will i) explore the mechanistic role of cRel homodimers in macrophage activation; and ii) investigate p50 homodimer specific gene regulation in macrophage activation. This research proposal focuses on cRel and p50 homodimers due to their potent activation downstream of viral and bacterial PRRs and their highly specific roles in immune cell activation. Upon completion, this research will provide novel insights into the regulatory logic employed by NFkB by revealing the underlying mechanisms that make dimer specific functions possible. Further, it could uncover specific therapeutic targets for immune system modulation to help slow or halt exaggerated immune cell activation seen in sepsis and ARDS.

项目摘要 世界卫生组织（WHO）估计，每年约有600万人死于败血症， 低收入国家和中等收入国家的负担最重。根据世界卫生组织的数据， 怀孕是产妇败血症的结果，其中95%以上的病例发生在发展中国家。最后， 美国疾病控制和预防中心估计，3-17%的COVID-19患者将发展为 急性呼吸窘迫综合征（ARDS）是该患者人群死亡的主要原因。败血症 和ARDS代表了感染期间免疫系统过度激活和失调的严重后果。 虽然这种病理学的负担是公认的，但这种临床恶化的分子基础 仍然知之甚少。NFkB是一种普遍存在的转录因子，在病毒和细菌感染期间被激活。 感染以控制先天免疫细胞行为，因此可能是免疫失调的关键因素。 NFkB是含有5个亚基（cRel、RelA、p50、p52和RelB）的TF家族，所述亚基组合地相互作用， 形成15种可能的二聚体物质来调节基因表达。虽然NFkB已经被很好地研究，但仍然存在一个 缺乏研究单个NFkB二聚体在免疫细胞活化中的功能。初步 分析支持中心假设，即NFkB的每个二聚体具有独特的生物学功能。理解 单个NFkB二聚体的作用可能为精确调节促炎基因开辟途径， 表情此外，我的数据支持这样的假设，即cRel同源二聚体对于选择性的免疫应答是必需的。 调节一小群基因，包括IL 12 b;和与共调节蛋白相关的p50同源二聚体 激活关键的促炎基因，包括IL 6、IL 1b和Lcn 2。这项研究使用了骨髓 衍生的巨噬细胞模型系统与原代腹腔巨噬细胞提取物的组合 用E.大肠杆菌或在体内用盲肠结扎和穿孔脓毒症模型，以定义二聚体 NF κ B在巨噬细胞活化中的作用及其二聚体特异性基因的分子机制 调控该提议将i）探索cRel同源二聚体在巨噬细胞活化中的机制作用;以及 ii）研究巨噬细胞活化中p50同源二聚体特异性基因调控。本研究重点 对cRel和p50同源二聚体的作用，这是由于它们在病毒和细菌PRR下游的有效活化以及它们的 在免疫细胞活化中的高度特异性作用。完成后，这项研究将提供新的见解， 通过揭示使二聚体特异性功能的潜在机制， 可能此外，它可以发现免疫系统调节的特定治疗靶点，以帮助减缓或停止 在败血症和ARDS中观察到的过度免疫细胞活化。