GBPs as new inflammsome regulators during mammalian host defense

GBP 作为哺乳动物宿主防御过程中新的炎症调节剂

基本信息

批准号：
8929155
负责人：
John David MacMicking
金额：
$ 41.63万
依托单位：
YALE UNIVERSITY
依托单位国家：
美国
项目类别：
财政年份：
2014
资助国家：
美国
起止时间：
2014-09-19 至 2019-08-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/8929155
关键词：
Acute Adjuvant Bacteria Bacterial Infections Binding Proteins Biochemical Bioinformatics Biological Biology Blood Caspase Caspase-1 Cell Death Cells Cleaved cell Complement Complex Data Detection Disease Engineering Excision Exhibits Family Family member Gastroenteritis Genes Genetic Genetic study Gram-Negative Bacteria Guanosine Triphosphate Phosphohydrolases Health Host Defense Human Immune Immune system Immunity Infection Inflammation Inflammatory Integration Host Factors Intensive Care Units Interleukin-1 Interleukin-18 Knockout Mice Lesion Ligands Lytic Macromolecular Complexes Mediating Molecular Mus Parasites Pathway interactions Property Protein Family Proteins Research Resistance to infection Salmonella Salmonella typhimurium Sensory Sepsis Side Signal Transduction Site Sterility Stimulus Testing Therapeutic Tissues Variant Virus Work antimicrobial base cytokine foodborne fungus gain of function genetic approach genome-wide guanylate human disease in vitro activity in vivo loss of function macrophage man microbial mutant pathogen pathogenic bacteria protein function receptor reconstitution research study response sensor therapy design

项目摘要

DESCRIPTION (provided by applicant): Inflammasomes alert the mammalian immune system to the presence of infection and tissue damage. These sensory complexes activate caspase-1 in the "canonical" pathway to cleave IL-1 family cytokines for secretion and eliminate infected host cells via a form of lytic cell death termed pyroptosis. In addition, a new "non- canonical" inflammasome has emerged that enlists caspase-11 specifically in response to Gram-negative bacteria. How each pathway discriminates microbial from danger signals and the host proteins responsible for this functional dichotomy remain unknown. Both questions are central to understanding the biology of inflammasome-mediated host defense. Here, we tackle this issue by focusing on a new family of 65-73kDa immune GTPases termed the Guanylate binding Proteins (GBPs) that uncouple these two activities. GBP5 specifically promotes canonical NLRP3 inflammasome activation to microbial but not danger signals, the first such protein to exhibit this profile. Subsequent work has found GBP1 and GBP2 confer the same selectivity. Thus the GBPs offer a unique opportunity to understand how one side of this bimodal response operates. In Aim 1 we will test whether GBP1, GBP2 and GBP5 promotes not only the canonical inflammasome pathway but also the non-canonical inflammasome triggered by Gram-negative bacterial stimuli. This will be examined using genetically-deficient human and mouse macrophages as well as newly-created Gbp1-/-, Gbp2-/- and Gbp5-/- mice infected with Salmonella typhimurium (Stm) variants that stimulate either inflammasome pathway. Our powerful genetic approach will reveal which GBP governs what inflammasome activities in vitro and in vivo. Thereafter, we will dissect the molecular mechanisms used by the inflammasome-related GBPs to confer their intracellular functions as part of Aim 2. Here gene-deficient macrophages complemented with GBP mutants with distinct biochemical lesions will test whether they are involved in cytosolic ligand detection or spatial assembly of the inflammasome complex during infection. "Reconstitution" studies will also reveal if the core inflammasome machinery is physically assembled by the GBPs as part of this macromolecular complex. Collectively, our proposal examines a new set of host factors that partition the inflammasome response with important implications for human therapies designed to promote antimicrobial activities while avoiding tissue damage.

描述（由申请人提供）：炎症小体向哺乳动物免疫系统发出感染和组织损伤的警报，这些感觉复合物在“规范”途径中激活 caspase-1，以裂解 IL-1 家族细胞因子进行分泌，并通过消除受感染的宿主细胞。此外，还出现了一种新的“非典型”炎症小体，它专门针对 caspase-11 进行响应。每种途径如何区分微生物和危险信号以及导致这种功能二分性的宿主蛋白仍然未知，这两个问题对于理解炎症体介导的宿主防御的生物学至关重要。一个新的 65-73kDa 免疫 GTP 家族被称为鸟苷酸结合蛋白 (GBP)，它可以解开这两种活性，从而特异性促进典型的 NLRP3 炎症小体激活。微生物而非危险信号，随后的工作发现 GBP1 和 GBP2 具有相同的选择性，因此 GBP 提供了一个独特的机会来了解这种双峰反应的一侧如何运作。测试 GBP1、GBP2 和 GBP5 是否不仅促进典型炎症小体途径，而且还促进由革兰氏阴性细菌刺激触发的非典型炎症小体。遗传缺陷的人类和小鼠巨噬细胞以及感染鼠伤寒沙门氏菌 (Stm) 变体的新创建的 Gbp1-/-、Gbp2-/- 和 Gbp5-/- 小鼠，这些变体刺激任一炎症小体途径，我们强大的遗传方法将揭示哪种 GBP。控制炎症体在体外和体内的活性此后，我们将剖析炎症体相关 GBP 所使用的分子机制，以赋予其细胞内功能，作为其一部分。目标 2. 此处，基因缺陷型巨噬细胞与具有不同生化损伤的 GBP 突变体互补，将测试它们是否参与感染期间的胞质配体检测或炎性体复合物的空间组装，“重建”研究还将揭示核心炎性体机制是否在物理上。总的来说，我们的提案检查了一组新的宿主因素，这些因素划分了炎症小体反应，这对于旨在促进人类治疗的重要意义。抗菌活性，同时避免组织损伤。