Modeling Human Alveolar Architecture Using Expandable Lung Progenitors in 3D and ALI Cultures: A Platform for Investigation of Alveolar Differentiation and Fibrosis-Related Pathologies
| Authors | |
|---|---|
| Year of publication | 2025 |
| Type | Conference abstract |
| MU Faculty or unit | |
| Citation | |
| Description | The regeneration of human alveolar epithelium is a dynamic and tightly regulated process. Culturing distal lung epithelial cells capable of forming functional alveolar structures remains a challenge due to their architectural complexity and tendency to rapidly differentiate or enter senescence in vitro. Recent protocols employing Wnt/Yap activation and TGFß inhibition have enabled the differentiation of lung progenitors into alveolar type 2 (AT2) and type 1 (AT1) cells, yet the mechanisms governing alveolar development and fibrotic transformation remain incompletely understood. Moreover, there is a pressing need for robust and reproducible in vitro models that reflect the physiological and pathological features of the human lung. Our lab previously developed a protocol to generate expandable lung epithelial progenitors (ELEPs) from human embryonic stem cells (hESCs) and induced pluripotent stem cells (iPSCs) characterized by stable expression of NKX2.1 and prosurfactant proteins B and C, and capability to differentiate to airway and alveolar structures in 3D and in vivo contexts. In this study, we aimed to differentiate ELEPs into more mature alveolar phenotypes under air-liquid interface (ALI) and 3D culture conditions using defined modulators of signaling pathways. Under ALI conditions, ELEPs demonstrated morphological and protein-level hallmarks of differentiation, including SPC processing, caveolin-1 expression, and early extracellular matrix production (e.g., collagen I). The prolonged differentiation activated ER stress responses linked to transitional AT2/AT1 states and cellular senescence—features often associated with fibrotic lung diseases. In 3D cultures, ELEPs maintained prolonged viability and exhibited structural and molecular features closely resembling alveolar networks. Therefore, ELEPs can recapitulate key aspects of alveolar maturation and pathological remodeling. ELEPs represent a powerful in vitro platform for modeling alveolar differentiation and provide a promising tool for investigating mechanisms underlying pulmonary fibrosis, including epithelial responses, matrix remodeling, and aberrant differentiation. This system may also support preclinical testing of antifibrotic therapies. This work was supported by the Czech Science Foundation (grant no. GA23-06675S), MZČR-RVO (FNBr, 65269705), and Masaryk University (grant no. MUNI/A/1738/2024). |
| Related projects: |