Microengineered alveolar array lung-on-chip with hydrogel membrane and simulated breathing mechanics for anti-fibrotic testing

Abstract We present a precision-engineered lung-on-chip platform that replicates the biomechanical and structural features of the human alveolar microenvironment for respiratory disease modeling and therapeutic evaluation. At the core of the device is a thin, suspended hydrogel membrane composed of biologically relevant collagen and elastin, engineered to mimic the dimensions and mechanical fragility of the native alveolar basement membrane. This membrane supports a geometrically defined array of alveolar units, each capable of undergoing finely controlled, physiologically relevant deflections under cyclic mechanical actuation—emulating the subtle deformations that occur during human breathing. To address the challenges posed by the membrane’s mechanical fragility and the requirement for accurately controlled micron-scale deflections, the platform is fabricated using precision injection molding. This manufacturing strategy ensures structural integrity and reproducibility, creating a rigid support structure around the suspended hydrogel membrane. The design is integrated into a SBS microwell plate format, facilitating robust fluidic interfacing, consistent cyclic actuation, and medium-throughput operation. Human alveolar epithelial cells and lung fibroblasts are co-cultured on a membrane and subjected to cyclic biomechanical stress that mimics respiratory movements. We demonstrate that cyclic stretching significantly amplifies fibrotic signaling in the presence of transforming growth factor-beta 1 (TGF- β 1), evidenced by increased expression of extracellular matrix (ECM) components such as collagen I, collagen III, and fibronectin. Treatment with the anti-fibrotic drug nintedanib reduced expression of ECM proteins and plasminogen activator inhibitor-1 (PAI-1), validating the system’s utility for pharmacological testing. This alveolar array-based lung-on-chip system bridges a critical gap between conventional in vitro models and the physiological complexity of human lung tissue, offering a robust platform for mechanistic studies and preclinical evaluation in pulmonary fibrosis and related disorders.