In-Vitro Model of the Microscale Alveolar Environment

The present work describes the development of a novel micro-nanoscale system that more closely resembles the alveolar-capillary barrier in the lung by recapitulating different parameters of the cellular microenvironment, including fibrous geometry, fiber stiffness, chemistry, and cell-cell interactions. The system consists of a three-dimensional multilayered structure. Two microchannel chambers that resemble alveolar/airway space and the capillary lumen, interfaced with a porous mesh of polymeric nanofibers that act as the basal substrate for seeding lung epithelial and endothelial cell. The top and bottom chambers of the device were fabricated using soft lithography techniques, while the nanofiber mesh was obtained via electrospinning. Human alveolar epithelial cells (A549) and human umbilical vein endothelial cells (HUVEC) were successfully co-cultured using this system. Various cellular and molecular biology techniques are being employed to investigate injury patterns and overall cell responses under different circumstances which mimic various lung disorders such acute lung injury, pulmonary fibrosis and emphysema.