A Microphysiological Mimicry of Human Lung-Bone Marrow Organ-Organ Crosstalk On-a-Chip

项目总结。 几种新的具有流行潜力的威胁全球卫生安全的呼吸道传染病 都是在过去20年里出现的。甲型流感病毒(IAV)占新出现的呼吸道病毒的50%，可以 造成相当大的发病率和死亡率。IAV可以感染多种鸟类和哺乳动物，包括 人类，并具有非凡的进化和适应新宿主的能力。尽管在以下方面取得了巨大进展 病毒学和流行病学，哪种IAV亚型或毒株将导致下一次暴发仍是不可预测的。 重要的是，没有临床模拟的、与病理生理学相关的和容易在体外获得的。 用于预测人类新出现和重新出现的流感病毒致病性的多器官系统。 最近令人信服的证据表明，两种主要的骨髓(BM)先天产生的作用是相反的 免疫细胞在IAV感染结局中的作用，中性粒细胞提供保护和增加循环 单核细胞与病理增加有关。因此，选择性动员这两个不同的细胞中的任何一个 对IAV肺部感染的反应类型可以间接揭示给定病毒的潜在致病性 紧张。这个项目的总体目标是开发一种高度创新的、简单化的、但又先进和复杂的 利用器官芯片技术建立人体流感感染的生理相关体外模型 通过临床和体内复制预测不同IAV毒株的毒力和感染性-免疫学观察 感染严重程度的相关因素。更具体地说，我们将设计一种首创的流体集成多 器官系统，使用原代人类来源的细胞重建BM-肺轴，用于实时分析 应对流感挑战的炎症和白细胞动员。我们的中心假设是，这 动态活微系统可概括不同免疫细胞动员和组织病理学 体外对高致病力与低致病性IAV感染的反应。为了解决这一假设，我们 提出以下具体目标：(1)设计一种活的、具有造血活性的人BM-on-a-Chip，并 通过微流体将其连接到我们团队之前开发的人类肺部芯片上的小气道 表征动态平衡生理学和器官-器官串扰；以及(3)挑战BM-肺部微系统 气载IAV在节律呼吸和复制差异白细胞动员和组织损伤 对明显致病的病毒株的反应。这种新颖的平台在仿真和预测方面具有很大的潜力 IAV的致病性(例如，在暴发、大流行期间或当推测存在高毒力毒株时)； 利用从期望的捐赠者/患者群体中分离的人类细胞，而不需要使病毒适应宿主 (根据某些动物研究的要求)。此外，它还可以通过以下方式大大加快药物开发研究 个性化药物疗效测试和确定新的治疗靶点。

PROJECT SUMMARY. Several new viral respiratory tract infectious diseases with epidemic potential that threaten global health security have emerged in the past 20 years. Influenza A viruses (IAVs) comprise 50% of the emerging respiratory viruses and can cause substantial morbidity and mortality. IAVs can infect a diversity of avian and mammalian species, including humans, and have the remarkable capacity to evolve and adapt to new hosts. Despite the tremendous progress made in virology and epidemiology, which subtype or strain of IAV will cause the next outbreak remains unpredictable. Importantly, there is no clinically simulating, pathophysiologically relevant, and readily available in vitro multi-organ system for predicting the pathogenicity of emerging and re-emerging influenza viruses in humans. Recent compelling evidence have revealed opposing roles for two major classes of bone marrow (BM)-produced innate immune cells in shaping the outcome of IAV infection, with neutrophils offering protection and increase in circulating monocytes being associated with increased pathology. Thus, selective mobilization of either of these two distinct cell types in response to pulmonary infection with IAV can indirectly reveal potential pathogenicity of a given viral strain. The overarching goal of this project is to develop a highly innovative, reductionist, yet advanced and complex, physiologically relevant in vitro model of influenza infection in humans utilizing Organ-on-Chip technology in order to predict virulence and infectivity of different IAV strains, by reproducing clinically and in vivo-observed immunological correlates of infection severity. More specifically, we will engineer a first-in-kind fluidically integrated multi- organ system that recreates BM-lung axis, using primary human-derived cells, for real-time analysis of inflammation and leukocyte mobilization in response to influenza challenge. Our central hypothesis is that this dynamic living microsystem can recapitulate differential immune cell mobilization and tissue pathology in response to high-pathogenicity vs. low-pathogenicity IAV infections in vitro. To address the hypothesis, we propose the following specific aims: (1) to engineer a living and hematopoietically active human BM-on-a-Chip and microfluidically link it to a human Lung Small Airway-on-a-Chip that our team has previously developed and characterize homeostatic physiology and organ-organ crosstalk; and (3) to challenge the BM-Lung microsystem with airborne IAVs under rhythmic breathing and reproduce differential leukocyte mobilization and tissue damage in response to distinctly pathogenic viral strains. Such a novel platform holds great potential in emulating and predicting pathogenicity of IAVs (e.g., during outbreaks, pandemics or when presence of a highly virulent strain is speculated), utilizing human cells isolated from desired donor/patient populations, and without needing to adapt the virus for host (as required for some animal studies). In addition, it can considerably accelerate drug development studies by enabling personalized drug efficacy testing and identification of new therapeutic targets.