Distribution of MHC II positive dendritic cells (DCs) and macrophages in the lung.

Mice were killed 12 days after intrapulmonary injection of adenoviral gene vector expressing murine granulocyte-macrophage colony-stimulating factor (AdGM-CSF), Addl70-3, or phosphate-buffered saline. Lung tissues were isolated and fixed in 10% formalin and 3-cm sections were immunostained with monoclonal anti-MHC II M5 antibody and 50% hematoxylin counterstaining. (A) Addl70-3 control vector treatment; (B) AdGM-CSF treatment. Many MHC II-positive cells are seen in Figure 6B, some intraepithelial DC are marked with arrowheads. Bronchial lumen is marked by b. (Magnification for both panels is 450.)