QUANTITATIVE ASSESSMENT OF THE EPITHELIA AND INFLAMMATORY CELL-POPULATIONS IN LARGE AIRWAYS OF NORMALS AND INDIVIDUALS WITH CYSTIC-FIBROSIS

Nasal and bronchial brushings and bronchial biopsies were evaluated fr om patients with cystic fibrosis (CF) and from normal subjects to quan tify epithelial and inflammatory cell types. Epithelia in both groups were dominated by ciliated cells. The relative proportions of epitheli al cells recovered by brushing and biopsy were similar, but with more basal cells from biopsies than from brushings. In nasal brushings, the numbers and percentages of epithelial subtypes were similar in both g roups. In bronchial brushings, the number of recovered cells was 2.5-f old increased in the CF group compared with that in the normal group b ecause of large numbers of neutrophils. The proportion of ciliated cel ls was lower in the CF group than in the normal group. Thus, even thou gh the CF transmembrane conductance regulator mutations are expressed similarly in the nasal and bronchial epithelium in CF, the consequence s are different, with little inflammation and no changes in the propor tions of epithelial cells in the nasal epithelium, compared with marke d neutrophil inflammation on the epithelial surface and significant ch anges in epithelial populations in the large airways. Airway brushing permits repetitive evaluation of the airway epithelium in CF, a useful methodology in the assessment of new therapies for this disorder.