(175av) An Engineered Culture Model to Mimic the Physical Boundary Conditions of the Lung Epithelium

The cells that line the airways of the lung are exposed to air on one side and a pliable tissue on the opposite side. Air-liquid interface (ALI) cultures are considered to be the gold standard to model respiratory diseases, but the traditional membranes that are used as substrata are orders of magnitude stiffer than the tissues of the lung. Here, we graft polyacrylamide (PA) gels onto the surfaces of transwell membranes to create ALI culture models that more accurately mimic the physical boundary conditions of the lung epithelium. The stiffness of these PA gels can be tuned to cover the physiological range of healthy and diseased lung epithelial tissue. We find that the photoinitiator benzophenone enhances the grafting of these gels onto the transwell membranes without affecting the intended stiffness of the gels. We show that human airway epithelial cells exhibit different morphologies and functional phenotypes when cultured at ALI on PA gels of different stiffness. This engineered culture model can be used to investigate the effects of fibrotic stiffening on viral transmission and airway injury.