Morphogenic accommodations for unidirectional airflow in the chicken lung

Unidirectional airflow in the avian lung enables gas exchange during both inhalation and exhalation. Stereo-seq spatial transcriptomics reveal a third, chicken-specific alveolar cell type expressing KRT14, hereby named luminal cells. Luminal, alveolar type 2, and alveolar type 1 cells sequentially occupy concentric zones radiating from the parabronchial lumen. Our study explores the evolutionary space of lung diversification and lays the foundation for functional analysis of species-specific genetic determinants. E20 chicken lungs were harvested, and flash frozen in Tissue-Tek OCT medium in ethanol/dry ice bath, and then stored at -80°C until used for a Stereo-seq experiment. Cryo-sections were cut at the thickness of 10 μm and mounted on Stereo-seq permeabilization chips.

鸟类肺部的单向气流可在吸气与呼气全过程中完成气体交换。空间转录组测序（Stereo-seq）揭示了第三种表达KRT14的鸡特异性肺泡细胞类型，我们将其正式命名为腔细胞（luminal cells）。腔细胞、肺泡Ⅱ型细胞与肺泡Ⅰ型细胞依次占据由副支气管腔向外辐射的同心区域。本研究探究了肺部多样化的进化空间，为物种特异性遗传决定因子的功能分析奠定了基础。本研究收集E20期鸡胚肺部组织，将其置于乙醇-干冰浴中的Tissue-Tek OCT包埋剂内快速冷冻，随后保存于-80℃冰箱直至用于Stereo-seq实验。研究人员将组织块切成厚度为10 μm的冰冻切片，并将切片贴附于Stereo-seq透化芯片上。