Figure 4. Epithelial damage and apoptosis and localization of bacteria in the gastrointestinal epithelium of C. jejuni–infected Muc1^–/– and Muc1^+/+ mice.

Tissue type, mouse genotype, time after inoculation, and a summary of the features demonstrated are shown above each photomicrograph. (A) H&E staining; arrows show shed epithelial cells. Immunohistochemical detection counterstained with hematoxylin of (B) activated caspase-3 and (C) C. jejuni (Cj). Arrows indicate the presence of C. jejuni. Scale bars: 50 μm (A and B); white scale bars: 20 μm (C); black scale bars: 10 μm (C).