Modeling the Human Immune Response to Severe Influenza Infection in an Immunocompetent Lung-on-Chip

Severe influenza affects 3-5 million people worldwide each year, resulting in more than 300,000 deaths annually. However, standard-of-care antiviral therapeutics have limited effectiveness in these patients. Current preclinical models of severe influenza fail to recapitulate the human immune response to severe viral infection accurately. Here, we develop an immune-competent, microvascularized, human lung-on-chip device to model the small airways, successfully demonstrating the cytokine storm, immune cell activation, epithelial cell damage, and other cellular- and tissue-level human immune responses to severe H1N1 infection. We find that IL-1β and TNF-α play opposing roles in the initiation and regulation of the cytokine storm associated with severe influenza. Furthermore, we discover the critical stromal-immune CXCL12-CXCR4 interaction and its role in immune response to infection. Our results underscore the importance of stromal cells and immune cells in microphysiological models of severe lung disease, describing a scalable model for severe influenza research. We expect the human lung-on-chip device to enable critical discoveries in respiratory host-pathogen interactions, therapeutic side effects, vaccine potency evaluation, and crosstalk between systemic and mucosal immunity in human lung. Four samples each comprised of 10 pooled lung-on-chip devices. The lung-on-chip is an immune-competent, microvascularized model including human umbilical vein endothelial cells (HUVECs), normal human lung fibroblasts, small airway epithelial cells, intersitial macrophages, interstitial dendritic cells, airway macrophages, and RBC-depleted whole blood. The four samples represent (1) uninfected healthy control, (2) severe H1N1 infected devices (MOI=10) at 8 hours post infection, (3) severe H1N1 infected devices (MOI=10) at 24 hours post infection, and (4) severe H1N1 infected devices (MOI=10) at 48 hours post infection,

每年全球有300万至500万人罹患重症流感，年致死病例超30万。然而，当前临床标准的抗病毒治疗方案对这类患者的疗效有限。现有的重症流感临床前模型均无法精准复现人类针对重症病毒感染的免疫应答过程。在此研究中，我们开发了一款具备免疫活性、微血管化的人源肺芯片（human lung-on-chip）装置以模拟人体小气道，并成功复现了重症H1N1感染时的细胞因子风暴、免疫细胞激活、上皮细胞损伤等人类在细胞与组织层面的免疫应答反应。我们发现，IL-1β与TNF-α在重症流感相关细胞因子风暴的启动与调控过程中发挥着截然相反的作用。此外，我们还揭示了关键的基质-免疫细胞CXCL12-CXCR4相互作用及其在感染免疫应答中的功能。本研究结果凸显了基质细胞与免疫细胞在重症肺部疾病微生理模型中的重要性，同时为重症流感研究提供了一款可规模化应用的模型体系。我们预期，这款人源肺芯片装置将助力呼吸道宿主-病原体互作、治疗副作用、疫苗效力评估以及人类肺部系统性免疫与黏膜免疫串扰等领域的突破性发现。本数据集共包含4组样本，每组样本由10个汇集整合的肺芯片装置组成。该肺芯片是一款具备免疫活性的微血管化模型，其组成包括人脐静脉内皮细胞（human umbilical vein endothelial cells, HUVECs）、正常人肺成纤维细胞、小气道上皮细胞、间质巨噬细胞、间质树突状细胞、气道巨噬细胞以及去除红细胞的全血。4组样本分别为：(1) 未感染的健康对照组；(2) 感染后8小时的重症H1N1感染组（感染复数multiplicity of infection, MOI=10）；(3) 感染后24小时的重症H1N1感染组（MOI=10）；(4) 感染后48小时的重症H1N1感染组（MOI=10）。