Reconstructing Cell-Cell Interactions in Diverse Inflammatory Environments

摘要 中性粒细胞是最丰富的天然免疫细胞类型，在清除感染、愈合伤口、 以及修复受损的组织。我们的实验室试图了解不同的炎症信号如何调节 利用设计用于模拟体内生物学的体外工程平台研究中性粒细胞对炎症的反应 与人类细胞。具体地说，我们感兴趣的是确定(I)如何分泌炎症信号，(Ii) 多细胞相互作用，以及(Iii)细胞外基质调节中性粒细胞的行为，其长期目标是 确定调节中性粒细胞募集和功能的靶点以治疗感染和中性粒细胞相关 疾病。为了正常发挥功能，中性粒细胞必须整合由每种炎症释放的独特信号集 将环境转化为特定的、定向的和严格管制的响应。中性粒细胞募集缺陷，过度 中性粒细胞渗透或中性粒细胞功能控制不当会导致慢性感染、组织 损害和疾病的进展，包括癌症、心血管疾病、自身免疫性疾病和 纤维化症。中性粒细胞反应的各个步骤(激活、外渗、迁移和抗菌 功能)由被激活的 血管系统、组织驻留细胞、循环细胞和病原体；然而，不同的机制通过 这些可溶信号和细胞群中的每一个都调节中性粒细胞的招募和功能 未定义。重要的是，中性粒细胞的行为如何随着不同的炎症信号而变化，以及如何 中性粒细胞将多个线索整合到定向反应中仍然是一个悬而未决的问题。这种知识鸿沟 由于当前实验平台的限制，无法捕获复杂的环境 信号、多细胞相互作用或体内环境的三维结构。要解决这个问题 挑战，我们最近开发了一种新型的芯片上炎症设备，它包括 炎症环境包括模型血管、原代人体免疫细胞、细胞外基质、 和一个活的病原体或促炎细胞因子的来源来研究原始的人类中性粒细胞反应 在生理相关的体外模型中。在接下来的五年里，我们将利用我们的 芯片上炎症设备，以开发对单个炎症刺激如何进行全面了解 (病原体、病原体相关分子模式、损害相关分子模式、细胞因子)和 与各种炎性细胞群(内皮细胞、周细胞、巨噬细胞、血小板)的相互作用 调节中性粒细胞功能。我们将确定关键的信号分子和广泛的信号网络枢纽 调节中性粒细胞的反应或对中性粒细胞对个别刺激的反应是唯一重要的。这 我们的工作朝着确定治疗靶点以控制中性粒细胞行为的长期目标迈进 治疗炎症性疾病，并将通过进一步发展我们的 研究先天免疫反应的模块化、多细胞、生理相关的实验模型。

SUMMARY Neutrophils, the most abundant innate immune cell type, play a critical role in clearing infections, healing wounds, and repairing damaged tissues. Our laboratory seeks to understand how diverse inflammatory signals regulate the neutrophil response to inflammation using engineered in vitro platforms designed to mimic in vivo biology with human cells. Specifically, we are interested in determining how (i) secreted inflammatory signals, (ii) multicellular interactions, and (iii) the extracellular matrix regulate neutrophil behavior with the long-term goal of identifying targets to modulate neutrophil recruitment and function to treat infections and neutrophil-associated diseases. To properly function, neutrophils must integrate the unique set of cues released by each inflammatory environment into a specific, directed, and tightly regulated response. Defective neutrophil recruitment, excessive neutrophil infiltration, or improperly controlled neutrophil function contributes to chronic infections, tissue damage, and the progression of diseases including cancer, cardiovascular disease, autoimmune disease, and fibrosis. The individual steps of the neutrophil response (activation, extravasation, migration, and antimicrobial function) are coordinated by a wide variety of secreted proinflammatory signals released by the activated vasculature, tissue resident cells, circulating cells, and pathogens; however, the different mechanisms through which each of these soluble signals and cell populations regulate neutrophil recruitment and function are undefined. Importantly, how neutrophil behavior varies in response to differing inflammatory cues and how neutrophils integrate multiple cues into a directed response remain unanswered questions. This knowledge gap exists due to the limitations of the current experimental platforms, which fail to capture the complex milieu of signals, multicellular interactions, or three-dimensional architecture of the in vivo environment. To address this challenge, we have recently developed a novel inflammation-on-a-chip device that includes key aspects of the inflammatory environment including a model blood vessel, primary human immune cells, extracellular matrix, and a source of live pathogen or proinflammatory cytokine to investigate the primary human neutrophil response in a physiologically relevant in vitro model. Over the next five years, we will exploit the modularity of our inflammation-on-a-chip device to develop a comprehensive understanding of how individual inflammatory stimuli (pathogens, pathogen-associated molecular patterns, damage-associated molecular patterns, cytokines) and interactions with varied inflammatory cell populations (endothelial cells, pericytes, macrophages, platelets) regulate neutrophil function. We will identify key signaling molecules and signaling network hubs that broadly regulate the neutrophil response or are uniquely important for the neutrophil response to individual stimuli. This work builds toward our long-term goal of identifying therapeutic targets to control neutrophil behavior for the treatment of inflammatory diseases and will advance the study of inflammation by further developing our modular, multicellular, physiologically relevant experimental model for investigating the innate immune response.