Airway epithelial cells (AECs) are a crucial component of the lung airways, responsible for safeguarding our respiratory health by defending against inhaled particles like bacteria, viruses, air pollution particles, and other pathogens. Because AECs are anchored to extracellular matrix (ECM) proteins, they undergo different levels of shear stress due to respiratory airflow. However, traditional 2D AEC in vitro culture using transwell inserts is limited in providing adequate mechanical stimuli. Therefore, there is a need to develop a precise in vitro lung airway epithelium model.

In recent years, microfluidic lung-on-a-chip systems have become increasingly popular as they accurately mimic the airway tissue microenvironment, including cellular organization, tissue architecture, and mechanical cues such as cyclic stretching and airflow. However, achieving physiological relevance remains a challenge, as more accurate cell-cell and/or cell-matrix interactions, along with appropriate physiological stimuli, are necessary.

This thesis presents the road to developing a novel lung airway-on-a-chip that can culture AECs on a biological substrate with interchangeable hydrogel and membrane format. The AECs were cultured under a physiological airflow produced by a custom-made airflow system to investigate the mechanobiological effects of airflow-induced shear stress. The system revealed that AECs cultured under airflow exhibited improved mucociliary differentiations compared to conventional static air-liquid interface culture. Additionally, the airflow direction and pattern played a crucial role in cell viability and differentiation. In summary, these studies uncovered novel characteristics of AECs and demonstrated the accessibility of microfluidics for AEC studies.