Lonza’s Small Airway Epithelial cells (both normal and diseased) are isolated from the distal portion of the lung in the 1 mm bronchiole area. These cells are isolated from airway tubules 1mm in diameter and smaller. Anything with a diameter greater than 1mm, including anything vascularized, is removed. The alveoli sacs at the end of the bronchioli are incorporated into the SAEC populations. We routinely remove any airway passages that are visible, leaving the smallest of bronchioli and alveoli sacs