GSE99862
Early defects of airway mucin sialylation and of mucociliary clearance at the onset of lung pathogenesis in a pig model of cystic fibrosis
Chronic infection of the lungs by bacteria such as Pseudomonas aeruginosa plays an important role in the natural history of Cystic Fibrosis (CF). Altered mucin secretions and glycosylations are hallmarks of bacterial infections but their exact contributions to the development of chronic infection and/or inflammation remain to be established. We studied the lung environment in newborn CFTR-/- pigs, which closely mirrors the human CF phenotype at the levels of mucin glycosylation, mucociliary transport (MCT) and immune response to P. aeruginosa infections. We show an increased sialylation of mucins from the tracheal mucosa of CFTR-/- pigs, which is also associated to increased Pseudomonas aeruginosa adherence. RNA-seq analysis did not show any altered expression of inflammatory genes, nor of sialylation enzymes. CFTR-/- piglets were unable to clear P. aeruginosa from the airways, leading to increased bacteria time of residence in the airways. We propose that alterations in mucin sialylation and MCT directly contribute to the early development of a favorable environment for bacterial colonization of the CF airways in the absence of an intrinsic inflammation. Overall design: Four experimental groups were analyzed, including 9 CFTR+/+ and 10 CFTR-/- piglets.  Half of the animals from each group were inoculated with Pseudomonas aeruginosa.