Figure 2

The airways of LPI lungs contain high amount of cholesterol, cholesterol needles and foamy macrophage cells. (A) Cholesterol assay revealed over 60-fold increase in cholesterol level of LPI BALF compared to controls. Control samples were obtained from diagnostic BALF of a patient with bronchitis (BRO) and a patient who carries mutation in ABCA3 transporter (ABCA3). (B) Several needle-like structures reminiscent of cholesterol crystals (arrows) are present within LPI surfactant lipid. Bar: 10 μm. (C) Quantitative analysis show that a significantly higher numbers of Oil Red O positive cells are present in LPI BALF compared to control BALF. The inset image shows representative large and foamy Oil Red O positive cells (arrows). Data are expressed as the mean percentage of positive cells in total cells ± SEM. Student's t-test was performed with * p < 0.05. (D) Transmission electron microscopy of cell pellets obtained from 200 × g centrifugation of LPI BALF shows the presence of lipid-laden foamy macrophage cells (arrow) and dying cells and/or lymphocytes in LPI BALF. (E) Many of the alveolar macrophages contained needle-like cholesterol crystals in their cytoplasm. Several long extracellular cholesterol needles are also visible (top right). Bar, 10 μm.