Distearoyl phosphatidylglycerol liposomes improve surface and transport properties of CF mucus

We have previously shown that a decreased level of phosphatidylglycerol in cystic fibrosis (CF) respiratory mucus is partly responsible for its marked adhesiveness and stickiness, which impair mucus transport, and that distearoyl phosphatidylglycerol (DSPG) was the most efficient form of phosphatidylglycerol in the enhancement of respiratory mucus clearance. The aim of our study was to analyse the effect of distearoyl phosphatidylglycerol liposomes on the transport by cough and cilia of cystic fibrosis respiratory mucus. The surface and transport properties of mucus were measured: 1) on native cystic fibrosis mucus; 2) on cystic fibrosis mucus complemented with DSPG liposomes at a non-cytotoxic concentration; and 3) on cystic fibrosis mucus complemented with water. The work of adhesion of cystic fibrosis mucus was significantly decreased by DSPG liposomes, but not by water. For mucociliary transport, the cystic fibrosis mucus was transported at a higher rate with DSPG liposomes and water compared to native cystic fibrosis mucus. The cough clearance of cystic fibrosis respiratory mucus was significantly improved in the presence of DSPG and water, but the effect was more pronounced with DSPG liposomes than with water. We conclude that the use of DSPG liposomes as a lubricating agent proves to be an interesting therapeutic approach for improving the cough and mucociliary transport in cystic fibrosis patients.