This is the first study to measure inducible nitric oxide synthase (iNOS) gene and protein expression quantitatively in primary epithelial cells from very young children with cystic fibrosis (CF).
Human neutrophils were activated by incubation with cytokines, added to monolayers of normal (16HBE14o-) and CF (CFBE41o-) bronchial epithelial cells and co-cultured for up to 72 h. Marked up-regulation of iNOS protein expression was seen in normal bronchial epithelial cells following neutrophil co-culture but the CF cells showed a significantly smaller increase (p<0.001).
To understand better the poor resistance to infections in the CF lung, the expression of the iNOS gene was investigated in explanted lungs from patients with cystic fibrosis (n = 13), bronchiectasis (n = 3), emphysema (n = 14), and in normal lungs (n = 8).