Isolation and metabolism of alveolar epithelial type II cells

A population of pulmonary cells enriched in epithelial type II pneumonocytes was isolated from Syrian hamsters using modifications of existing technology and identified by fluorescent microscopy. Briefly, the animals were euthanized, the heart-lung-trachea was removed, the lungs perfused intravascularly and intrabronchially and then gently trypsinized during a second bronchopulmonary lavage to free the epithelial components. The lungs were minced, the cell suspension filtered, the trypsin deactivated, the cell suspension refiltered, and the cells concentrated by centrifugation before separation on a discontinuous gradient of Ficoll. The enriched population of epithelial type II cells concentrated at the 1.058 to 1.090 interface. Incubation of these cells with α-glycerol (U--14C) phosphate for various times showed a linear uptake for 2 hours of the carbon-14 into triglycerides, phosphatidyl choline, and phosphatidyl glycerol which were identified in the total lipid extract by thin-layer chromatographic zonal scanning and liquid scintillation spectrometry. (U.S.)