Epithelial respiratory cells from cystic fibrosis patients do not possess specific Pseudomonas aeruginosa-adhesive properties

Abstract

Nasal polyp cells in primary culture from cystic fibrosis (CF) and non-CF patients were compared for the ability to bind Pseudomonas aeruginosa cells and for the presence of sulphated glycoconjugates at the epithelial cell surface. Quantitation of bacterial adhesion, by scanning electronmicroscopy, showed no significant difference between the cells cultured from CF and non-CF patients. Micro-organisms associated with ciliated cells were mainly aggregated, in contrast with those from non-ciliated cells. Sulphated glycoconjugates were identified on cells cultured from both CF and non-CF patients, regardless of whether or not these cells had attached bacteria. A matrix-like material that surrounded the aggregated bacteria was more prominent on cells cultured from CF patients than on those from non-CF patients. The interaction of aggregated P aeruginosa cells with polyp cells cultured from both CF and non-CF patients appeared to occur by means of this matrix material. Our findings suggest that chronic colonisation of the airways of CF patients cannot be explained by an increased affinity between the P. aeruginosa cells and the respiratory cell surface receptors in the CF patient. Nevertheless, the in-vitro observation that the matrix surrounding the bacteria reacted with a monoclonal antibody against respiratory mucins allows us to speculate that increased mucin secretion by cells from CF patients might, in vivo, play a decisive role in the interaction between P. aeruginosa and the respiratory epithelium.