Detection of human adenovirus (HAdV) proteins in liver and bone marrow. E1A, E2A, and capsid proteins in formalin-fixed, paraffin-embedded tissue samples underwent immunohistochemical analysis. A–D, Representative micrographs of liver sections from mice with acute infection, showing results of E1A staining (A and B), capsid staining (C), and E2A staining (D). E–G, Representative micrographs of bone marrow sections stained with E2A antibody, showing results for mock-infected mice (E), mice with acute infection (F), and mice with asymptomatic infection (G). Arrows point to cells that stained positive for each antibody. The scale bar is 0.5 µm. All pictures were taken at 20 times the original magnification.