Lipid composition of airway secretions from patients with asthma and patients with cystic fibrosis.

Lipids from the particulate material obtained from pulmonary lavage of patients with 
asthma and cystic fibrosis were isolated and characterized. In both cases, 
lipids constituted 30 to 40 per cent of the dry insoluble 
material and phosphatidylcholine was the predominant lipid. Significant amounts of phosphatidylethanolamine 
and phosphatidyglycerol were present. Hexosyl ceramides, spingomyelin, phosphatidylinositol, phosphatidylserine, and lyso(bis)phosphatidic 
acid were present as minor lipid components. Appreciable quantities of neutral 
lipids were also found. Significant amounts of lysophosphatides and free fatty 
acids were present only in the lavage sediment from patients with 
asthma, and not in patients with cystic fibrosis. Phosphatidylcholine, lysophosphatidycholine, sphingomyelin, 
and phosphatidylglycerol of asthmatic lavage, but not cystic lavage, were highly 
saturated, containing mostly palmitic acid. 