by Max Delbrück Center for Molecular Medicine Alveolar macrophages isolated from the lungs of wild-type mice (left) and Cebpb-deficient animals (right). Cells were stained using OilRed O staining to visualize intracellular lipids (red). Cells lacking Cebpb show a large, distended phenotype with high lipid deposition. Credit: AG Leutz, MDC The exchange of gases between the...