X-Ray Microanalysis of Respiratory Epithelial Cells in the Study of Cystic Fibrosis

One of the most important clinical symptoms associated with cystic fibrosis (CF) is obstructive airway disease and recurrent airway infections. The smaller airways in CF patients are blocked by viscous mucus, and infections are common and difficult to manage. Generally, lung disease is directly or indirectly the cause of death in CF. The viscous mucus in CF is likely to be a result of defective water transport in the respiratory epithelium. Water transport is coupled to chloride secretion, and it is strongly suspected that a defective chloride channel in the apical membrane of the respiratory epithelial cells is the basic error in CF. We therefore studied changes in the intracellular concentration of chloride (and other ions) by x-ray microanalysis of cultured respiratory epithelial cells under a variety of conditions.Tissues were obtained from material excised during polypectomy. The tracheal mucosa was digested with collagenase and the dispersed cells were plated onto Milliporefilters coated with human placental collagen.