IMPROVEMENT OF CYSTIC-FIBROSIS AIRWAY MUCUS TRANSPORTABILITY BY RECOMBINANT HUMAN DNASE IS RELATED TO CHANGES IN PHOSPHOLIPID PROFILE

The aim of this study was to test whether changes in mucus surface pro perties by rhDNase treatment could be related to an increased recovery of phospholipids. Purulent sputa from 18 patients with cystic fibrosi s (CF) were incubated with either rhDNase (4 mu g/ml) or control excip ient. The incubation of mucus samples with rhDNase induced a significa nt increase (p < 0.002) in the sol phase proportion (33.7 +/- 24.0%) c ompared with that obtained with excipient (12.6 +/- 12.4%). Phospholip ids were recovered in significantly (p < 0.05) greater amounts from bo th mucus gel and sol phases after incubation with rhDNase. The phospha tidylglycerol content of mucus sol phase was significantly increased b y rhDNase (p < 0.03), as well as the mucus gel phase surface propertie s and transport by ciliary activity and by cough (p < 0.05). The impro vement of mucus gel surface properties and transport capacity by cilia ry activity were significantly related to the increased recovery of ph osphatidylglycerol (r = -0.74, p < 0.03 and r = 0.94, p < 0.05, respec tively). These results suggest that rhDNase is able to increase the fr ee water content and alter the phospholipid profile of mucus, with a r elated improvement in CF mucus transportability.