The Isolation and In vitro Differentiation of Primary Fetal Baboon Tracheal Epithelial Cells for the Study of SARS-CoV-2 Host-Virus Interactions

The mucociliary airway epithelium lines the human airways and is the primary site of host-environmental interactions in the lung. Following virus infection, airway epithelial cells initiate an innate immune response to suppress virus replication. Therefore, defining the virus-host interactions of the mucociliary airway epithelium is critical for understanding the mechanisms that regulate virus infection, including Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2). Non-human primates (NHP) are closely related to humans; and provide a model to study human disease. However, ethical considerations and high costs can restrict the use of in vivo NHP models. Therefore, there is a need to develop in vitro NHP models of human respiratory virus infection that would allow for rapidly characterizing virus tropism and suitability of specific NHP species to model human infection. Using the olive baboon (Papio anubis), we have developed methodologies for the isolation, in vitro expansion, cryopreservation, and mucociliary differentiation of primary fetal baboon tracheal epithelial cells (FBTECs). Furthermore, we demonstrate that in vitro differentiated FBTECs are permissive to SARS-CoV-2 infection and produce a potent host innate-immune response. In summary, we have developed an in vitro NHP model that provides a platform for the study of SARS-CoV-2 infection and other human respiratory viruses. mRNA profiling of primary fetal baboon tracheal epithelial cells (FBTECs) differentiated on air-liquid interface (ALI) culture for 28 days.

黏液纤毛气道上皮（mucociliary airway epithelium）衬覆于人类气道表面，是肺部宿主与环境相互作用的核心位点。病毒感染后，气道上皮细胞会启动先天免疫应答以抑制病毒复制。因此，阐明黏液纤毛气道上皮的病毒-宿主相互作用，对于解析包括严重急性呼吸综合征冠状病毒2（Severe Acute Respiratory Syndrome Coronavirus 2，SARS-CoV-2）在内的病毒感染调控机制至关重要。非人灵长类动物（Non-human primates，NHP）与人类亲缘关系密切，是研究人类疾病的理想模型。然而，伦理考量与高昂成本限制了体内非人灵长类动物模型的应用。因此，亟需建立人类呼吸道病毒感染的体外非人灵长类动物模型，以快速表征病毒嗜性以及特定非人灵长类物种在模拟人类感染方面的适用性。本研究以橄榄狒狒（Papio anubis）为对象，建立了原代胎儿狒狒气管上皮细胞（primary fetal baboon tracheal epithelial cells，FBTECs）的分离、体外扩增、冷冻保存及黏液纤毛分化方法。此外，本研究证实经体外分化的FBTECs可被SARS-CoV-2感染并支持其复制，同时触发强烈的宿主先天免疫应答。综上，本研究建立了一种体外非人灵长类动物模型，为SARS-CoV-2感染及其他人类呼吸道病毒的研究提供了实验平台。本数据集包含经气液界面（air-liquid interface，ALI）培养28天分化的原代胎儿狒狒气管上皮细胞（FBTECs）的mRNA表达谱数据。