IN-VITRO STUDY OF THE BRONCHIAL-MUCOSA DURING PSEUDOMONAS-AERUGINOSA INFECTION

The route of bacterial infection of the lower respiratory tract is gen erally one of descent subsequent to colonisation of the oral and oroph aryngeal mucosa. The interaction between Pseudomonas aeruginosa (wild type) and the bronchial epithelium was studied in bronchial mucosal pr obes cultured in tissue culture medium. It was possible to demonstrate that, even after loss of the mucus layer, adherence between the bacte ria and the bronchial epithelium does not take place if ciliary functi on remains intact. Only after mechanical destruction of the bronchial epithelium, in proximity to squamous metaplasia or after loss or malfu nction of the cilia of the bronchial epithelial cells was adhesion bet ween bacteria and bronchial epithelial cells or basement membrane demo nstrated by electron microscopy. After loss of the cilia following ade novirus-infection, adhesion between P. aeruginosa and the bronchial ep ithelial cells was visible. These results indicate that ciliary functi on must be of crucial significance in bacterial epithelial colonisatio n.