Selective modulation of neutrophils in critical illness

摘要 危重病描述的是可能发生的免疫功能障碍导致的危及生命的状态 创伤性损伤、休克、烧伤或大手术。创伤诱导的免疫功能不全 继发感染的易感性是医院ICU死亡的重要原因。中性粒细胞 循环中最丰富的白细胞，对于宿主防御细菌和真菌病原体至关重要， 但由于其抗菌剂的非特异性和细胞毒性性质， 阿森纳官方创伤对中性粒细胞的影响导致免疫功能障碍，包括显著的缺陷 中性粒细胞发现和抵抗感染的能力，加上与诱导 组织损伤我的研究计划的长期目标是了解中性粒细胞的机制， 在健康和疾病中的募集和效应器功能。这个MIRA应用程序描述了我们的协同 方法来识别和理解中性粒细胞病理学机制在危重病。 首先，我们已经建立了一种创新的方法来获得离体中性粒细胞， 基因改造的障碍。这使我们能够使用以下方法进行多重正向遗传筛选： CRISPR-Cas9在嗜中性粒细胞中的作用，从而鉴定其募集的新机制方面（例如，整合素 活化）和抗微生物功能（例如，吞噬作用）。第二，我们建立了一个小鼠模型， 呼吸道感染继发失血性休克的危重病。因为肺特别 易受继发于创伤的感染，并且也易于发生嗜中性粒细胞介导的损伤，该模型 提供了一种方法来评估新的目标/策略，以促进中性粒细胞功能的选择性方面， 增强宿主防御而不加剧组织损伤。最后，我们将人类创伤患者 材料（血液，血浆，肺液），这些方法来探测疾病的特异性机制， 中性粒细胞反应。由于我们的研究将探讨基本的生物学机制，如整合素 激活，这项工作也将在多个领域产生广泛的影响。这些综合办法将共同 通过跨越分子、细胞和生物体/疾病，填补中性粒细胞生物学的主要知识空白 实验水平。

Abstract Critical illness describes the life-threatening state caused by immune dysfunction that can occur following traumatic injury, shock, burn or major surgery. Trauma-induced immune incompetence enhances susceptibility to secondary infections that are a significant cause of mortality in hospital ICUs. Neutrophils, the most abundant leukocyte in the circulation, are critical for host defense against bacterial and fungal pathogens, but they also induce bystander tissue injury due to the non-specific and cytotoxic nature of their antimicrobial arsenal. The effects of trauma on neutrophils contribute to immune dysfunction and include a significant deficit in neutrophil capacity to find and fight infection, coupled with a primed phenotype associated with inducing tissue damage. The long-term goals of my research program are to understand mechanisms of neutrophil recruitment and effector function in health and disease. This MIRA application describes our synergistic approaches to identifying and understanding mechanisms of neutrophil pathobiology during critical illness. First, we have established an innovative approach to derive neutrophils ex vivo that circumvents the technical barriers to their genetic modification. This enables us to perform multiplexed forward genetic screening using CRISPR-Cas9 in neutrophils, and thereby identify new mechanistic aspects of their recruitment (e.g., integrin activation) and antimicrobial function (e.g., phagocytosis). Second, we have established a mouse model of critical illness by respiratory infection secondary to hemorrhagic shock. As the lungs are particularly susceptible to infection secondary to trauma and are also prone to neutrophil-mediated injury, this model provides a means to evaluate new targets/strategies for promoting selective aspects of neutrophil function to enhance host defense without exacerbating tissue damage. Finally, we will apply human trauma patient material (blood, plasma, lung fluid) to these approaches to probe disease-specific mechanisms of the neutrophil response. Since our studies will interrogate fundamental biological mechanisms, such as integrin activation, this work will also have broad impact on multiple fields. Together, these integrated approaches will address major knowledge gaps in neutrophil biology by spanning the molecular, cellular and organism/disease levels of experimentation.