The Inflammasome: A Novel Biomarker in ALI/ARDS

描述(申请人提供)：炎症小体最近被描述为一种重要的蛋白质复合体，其中非NFkB介导的信号通路导致关键的促炎细胞因子上调，包括白介素1b和白介素18。我们小组的成员最近报道，炎症小体在小鼠脓毒症的促炎反应中起着关键作用，这种反应依赖于线粒体的完整性和对损伤的完整自噬反应。我们现在提供的数据支持炎症小体在预测人类感染相关的ALI/ARDS的严重程度和死亡率方面的重要作用。此外，我们的初步动物研究表明，他汀类药物通过激活炎症小体而加剧肺损伤和炎症。因此，我们假设炎症小体的激活在感染相关性ALI/ARDS的发展中起关键作用，他汀类药物的应用可能会在肺损伤过程中增加炎症小体相关的下游细胞因子。特别是，我们与ARDSNet SAILS试验研究人员的合作(他汀类药物与安慰剂在感染相关ALI/ARDS中的随机试验)在这项临床辅助试验RFA(HL-12-012)中提供了一个独特的机会，可以获得更多关键人体样本的收集，以解决这些重要的过程。因此，我们提出：特定目标1：使用前瞻性采集的血液(n=100)和来自安慰剂和他汀类药物治疗的SAILS受试者(n=600)的血浆样本，确定感染相关ALI/ARDS期间炎症小体的基因表达和蛋白水平。炎症小体的基因表达和蛋白水平将与60天死亡率和额外的SAILS试验次要结果相关。我们假设循环中的炎症体水平将作为感染相关ALI/ARDS严重程度和死亡率的生物标志物，他汀类药物治疗的受试者的炎症体水平将与临床结果相关。具体目的2：使用从接受安慰剂和他汀类药物治疗的SAILS受试者(n=100)以及从对照ICU受试者(n=100)分离的原代中性粒细胞和单核细胞，确定炎性小体复合体表达的细胞定位以及炎性小体激活对细胞反应和功能的作用。我们假设，确定哪些循环细胞是炎症体激活的主要来源将增加炎症体水平与临床结果相关性的敏感性，并且炎症体的局部激活将导致线粒体功能障碍，这种功能在他汀类药物存在时会得到加强。

DESCRIPTION (provided by applicant): The inflammasome has recently been described as an important protein complex in which a non-NFkB- mediated signaling pathway leads to up-regulation of key pro-inflammatory cytokines, including interleukin (IL)- 1b and IL-18. Members of our group recently reported that the inflammasome plays a critical role in pro- inflammatory response in murine sepsis, and this response is dependent upon mitochondrial integrity and an intact autophagy response to injury. We now present data supporting an important role for the inflammasome in predicting severity and mortality during human infection-related ALI/ARDS. Moreover, our preliminary animal studies demonstrate that statins exacerbate lung injury and inflammation via activation of the inflammasome. We therefore hypothesize that activation of the inflammasome plays a critical role in the development of infection-related ALI/ARDS and that statin administration may increase inflammasome-related downstream cytokines during lung injury. In particular, our collaboration with the ARDSnet SAILS trial investigators (a randomized trial of statins vs. placebo in infection-related ALI/ARDS) in this Ancillary Studies in Clinical Trials RFA (HL-12-012) provides a unique opportunity to obtain additional collection of key human samples to address these important processes. We therefore propose: Specific Aim 1: To determine gene expression and protein levels of the inflammasome during infection-related ALI/ARDS using prospectively collected blood (n=100) and banked plasma samples (n=600) from placebo- and statin-treated SAILS subjects. Gene expression and protein levels of the inflammasome will be correlated with 60-day mortality and additional SAILS trial secondary outcomes. We hypothesize that circulating inflammasome levels will serve as a biomarker of severity and mortality of infection-related ALI/ARDS and that inflammasome levels in statin-treated subjects will correlate with clinical outcomes. Specific Aim 2: To determine the cellular localization of expression of the inflammasome complex and role of inflammasome activation on cellular responses and function, using primary neutrophils and monocytes isolated from prospectively enrolled placebo- and statin-treated SAILS subjects (n=100), as well as primary cells isolated from control ICU subjects (n=100). We hypothesize that determining which circulating cells are the predominant source of inflammasome activation will increase sensitivity of the correlation of inflammasome levels with clinical outcomes and that localized activation of the inflammasome will result in mitochondrial dysfunction that will be enhanced in the presence of statin administration.