Figure 4. Accumulation of Mucus in Humans with Cystic Fibrosis and Animal Models of Cystic Fibrosis
Panels A-E. “Stringy” appearance of mucus arising from glands. Mucus secreted from submucosal glands in pulmonary airways remained in the gland duct in a 7-month-old baby with cystic fibrosis (A), a 2-month-old cystic fibrosis pig (B), and an 8-month-old cystic fibrosis ferret (C). Mucus also emerged from submucosal glands in ethmoid sinus olfactory epithelium that did not contain goblet cells (D, 1-month-old cystic fibrosis pig). Similar to mucus from submucosal glands, mucus arising from colonic crypts of newborn cystic fibrosis pigs can show a stringy appearance and adherence to the site of origin (E, newborn cystic fibrosis pig). Panels F-I. Lamellar appearance of mucus along epithelia. In affected intrapulmonary airways, mucus can have a lamellar appearance lying along airway walls (F, 2-month-old cystic fibrosis pig). A similar pattern of mucus arising from goblet cells can occur in ethmoid sinuses where respiratory epithelium lacks submucosal glands, and mucus can sometimes be traced back to the cells of origin (G, 1-month-old cystic fibrosis pig). Likewise, mucus can have a lamellar appearance and be traced back to the cell of origin in microgallbladder (H, newborn cystic fibrosis pig). Pancreatic ducts also can show obstruction by mucus (I, 6-month-old cystic fibrosis pig). The authors thank Drs. Marcus Nashelsky, and Morris Dailey (University of Iowa, Department of Pathology) for assistance with archival autopsy data.