Lung histology after in vitro infection of AM by AdmGM-CSF or AdNull and subsequent transfer of the genetically modified AM to the lung. Shown is light microscopy of hematoxylin/eosin-stained sections of formalin fixed lung 1 and 5 weeks after AM transfer. (A) Naive mice. (B) Mice receiving AM modified with AdNull 1 week previously. (C) Mice receiving AM modified with AdmGM-CSF 1 week previously. (D) Similar to (B), but after 5 weeks. (E) Similar to (C), but after 5 weeks. Bar = 100 μm.