Figure 1 Immunostaining of major histocompatibility complex (MHC) class II positive or CD11c positive cells in organs of mice injected or not injected with bacteria. Heart (A and B), intestine (C and D), kidney (E and F), and lung (G and H). Sections from Balb/c mice injected 24 hours previously with phosphate buffered saline (A, C, E, and G) or Escherichia coli (B, D, F, and H) were stained with anti-I-E^d (A–F) or anti-CD11c (G and H) monoclonal antibodies, and further counterstained with haemalun. Scale bar, 50 µm (A, B, C, D, G, and H), 100 µm (E and F).