Schematic representation of the MucilAir™ pseudostratied respiratory epithelium grown on the
surface of a porous membrane with culture medium on the basal side and air on the apical side. The
goblet cells secrete mucin proteins in a matrix composed of water, complex sugars, salts which form
the mucus. This matrix is distributed evenly on the surface of the epithelium by the ciliated cells to
form a protective layer. Basal cells are undierentiated cells with the potential to divide to form new
goblet cells and new ciliated cells. Inhaled chemicals (toxicants, medicine) can be metabolized by the
tissue and excreted in the basal media.