Figure 2.

Immunofluorescence microscopy of mouse small intestine (ileum) cross section. The confocal image shows the anatomical arrangement of epithelial cells (stained in red) and immune cells (dendritic cells stained in green, B cells stained in blue, and T cells stained in white). This arrangement suggests functional interactions between epithelial and immune cells for handling nonself antigens and microbiota present in the intestinal lumen. (Image provided by Marcello Chieppa, Lymphocyte Biology Section, Laboratory of Immunology, National Institute of Allergy and Infectious Diseases, National Institutes of Health).