Host innate responses induced by intracellular bacteria and cyclic-di-nucleotides

由细胞内细菌和环二核苷酸诱导的宿主先天反应

• 批准号: 8234234
• 负责人: RUSSELL E VANCE
• 金额: $ 34.6万
• 依托单位: UNIVERSITY OF CALIFORNIA BERKELEY
• 依托单位国家: 美国
• 财政年份: 2011
• 资助国家: 美国
• 起止时间: 2011-07-15 至 2016-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8234234
• 关键词: Address; Antibodies; Bacteria; Bacterial Physiology; Belief; Binding; Biochemical; Characteristics; Communicable Diseases; Cyclic GMP; Cyclic Nucleotides; Cytosol; DNA; Detection; Dinucleoside Phosphates; Dissection; Ethylnitrosourea; Flagellin; Genes; Genetic; Genetic Screening; Goals; Immune Targeting; Immune response; Immune system; Immunologic Monitoring; Immunotherapeutic agent; Interferon Type I; Interferons; Listeria monocytogenes; Mammalian Cell; Molecular; Morbidity - disease rate; Mus; Mutagenesis; Mutant Strains Mice; Mycobacterium tuberculosis; Natural Immunity; Nucleic Acids; Nucleotides; Pathway interactions; Pattern; Play; Production; Prokaryotic Cells; Proteins; Radiolabeled; Role; Second Messenger Systems; Shapes; Vaccine Adjuvant; Work; base; bis(3' ,5' )-cyclic diguanylic acid; design; extracellular; improved; mortality; mutant; novel; novel vaccines; pathogen; radiotracer; research study; response; second messenger; sensor

Intracellular pathogens remain a major cause of global mortality and morbidity. By evasion of extracellular defenses, such as antibodies, intracellular pathogens pose a unique challenge to the immune systems of their hosts. A fundamental question we address is how intracellular pathogens are sensed by the innate immune system. In the past few years, we and others have discovered that intracellular pathogens trigger a variety of different cytosolic immunosurveillance pathways. These pathways appear to play important roles in shaping protective innate and adaptive responses. However, the molecular basis of cytosolic immunosurveillance remains poorly characterized, and it is likely that additional pathways remain to be discovered. Our studies are motivated by our belief that a better understanding of innate immunity is central to the improved design of new vaccines, adjuvants and immunotherapeutics. Exciting recent work from our group and others has shown that unique bacterial nucleotides, cyclic-di-GMP and cyclic-di-AMP, are novel and potent stimulator of innate and adaptive immune responses. The field now confronts a major outstanding question: what is the host sensor that specifically detects cyclic-di-nucleotides? We are taking genetic and biochemical approaches to address this fundamental question. In what we believe is an exciting advance, our unpublished experiments have now converged on identification of the sensor as a host protein called Sting (Stimulator of interferon genes). We identified a novel Sting mutant mouse in a forward genetic screen using ENU mutagenesis in mice. Using this mutant, we found Sting is essential for responses to c-dinucleotides. In addition, we have recently found that radiolabelled c-di-GMP binds specifically to Sting. Thus, our Specific Aims are: (1) Determine how the interaction of Sting with cyclic-di-nucleotides leads to an IFN response (2) Distinguish the role of Sting in the cytosolic response to cyclic-di-nucleotides from the role of Sting in the cytosolic response to DNA, and distinguish these functions of Sting in the response to three intracellular bacterial pathogens (L. monocytogenes, M. tuberculosis, and L. pneumophila) (3) Identify novel regulators of innate immunity to three intracellular bacterial pathogens (L. monocytogenes, M. tuberculosis, and L. pneumophila) by continuing to perform forward genetic screens in mice.

细胞内病原体仍然是全球死亡率和发病率的主要原因。通过逃避细胞外 防御，如抗体，细胞内病原体对免疫系统构成了独特的挑战， 他们的主人。我们要解决的一个基本问题是细胞内的病原体是如何被先天的 免疫系统在过去的几年里，我们和其他人已经发现，细胞内病原体会引发一种 多种不同的胞质免疫监视途径。这些途径似乎在以下方面发挥着重要作用： 形成保护性的先天和适应性反应。然而，细胞质的分子基础 免疫监视仍然不清楚，可能还有其他途径有待研究。 发现了我们的研究是基于我们的信念，即更好地了解先天免疫是核心 新疫苗、佐剂和免疫治疗剂的改进设计。令人兴奋的最近工作从我们的 小组和其他人已经表明，独特的细菌核苷酸，环二GMP和环二AMP，是新的 和先天性和适应性免疫反应的有效刺激物。该领域现在面临着一个主要的突出 问题：专门检测环二核苷酸的宿主传感器是什么？我们将基因和 生物化学方法来解决这个基本问题。我们相信这是一个令人兴奋的进步， 我们未发表的实验现在集中在识别传感器作为宿主蛋白质，称为 Sting（干扰素基因刺激因子）。我们在正向遗传筛选中发现了一种新的Sting突变小鼠 使用小鼠中的ENU诱变。利用这个突变体，我们发现刺是必不可少的反应，c-二核苷酸。 此外，我们最近发现放射性标记的c-di-GMP特异性结合Sting。因此，在本发明中， 我们的具体目标是：（1）确定Sting与环状二核苷酸的相互作用如何导致IFN 反应（2）区分Sting在细胞溶质对环状二核苷酸反应中的作用和Sting在细胞溶质对环状二核苷酸反应中的作用。 Sting在胞浆中对DNA的反应，并区分Sting在三种反应中的这些功能 胞内细菌病原体（L.单核细胞增多症M.结核病和L.（3）确定新的 三种细胞内细菌病原体的先天免疫调节因子（L.单核细胞增生症、M.肺结核， 和L. pneumophila）通过继续在小鼠中进行正向遗传筛选。