Human Airway and Alveolar Organoids from Bronchoalveolar Lavage Fluid

Many lung diseases remain understudied due to a lack of experimental models. Lung organoids, which consist of self-organizing epithelial cells, provide versatile in vitro models for normal and abnormal biology, drug screening, gene editing, and personalized therapeutics. However, human organoids are generally derived from lung tissue, which is not commonly obtained and represents only a small fraction of lung pathologies. Induced pluripotent stem cells have provided an important alternative but require complex manipulation. Recently, one study reported airway organoids from bronchoalveolar lavage (BAL) fluid, though sample sizes and characterization were limited. Here, we demonstrate robust establishment of airway organoids from a variety of human BAL samples and show that these organoids consist predominantly of basal cells plus differentiated airway cell types including secretory, ciliated, KRT13+ “hillock,” and ionocyte cells. Furthermore, we report the development of BAL-derived alveolar organoids comprised of alveolar type 2 (AT2) cells. These techniques significantly expand the scope of lung diseases that can be studied using safely accessible primary human cells.