Figure 5. Dendritic cell distribution across the ocular surface of Aire-deficient mice. A: Immunofluorescence study of CD11c⁺ cells (red) demonstrates dendritic antigen presenting cells (APCs) in the basal epithelium (open arrowhead) and sub-epithelial stroma (arrow) of the conjunctiva (Cj), limbus (Lm), and central cornea (Co). Although CD11c⁺ cells are found in both Aire^+/− and Aire^−/− mice, significantly more are seen in Aire-deficient mice. CD11c⁺ cells are present throughout the whole layer of the cornea including the posterior stroma (solid arrow head) in Aire^−/− while they are largely absent in the posterior cornea in Aire^+/−. The dotted line represents the epithelial basement membrane in the limbus, and the blue nuclear counterstaining (DAPI) is used for orientation. Bar, 100 μm. B: Immunohistochemical study of MHC class II surface antigen (I-A^d) reveals an intense infiltration of activated dendritic APCs in the epithelium (open arrow head) and stroma (arrow) of the conjunctiva (Cj), limbus (Lm), and central cornea (Co) of Aire^−/− mice. By comparison, I-A^d+ cells are rarely apparent in the conjunctiva and limbus and are completely absent in the central cornea of Aire^+/− mice. The asterisk denotes goblet cells. Bar, 100 μm. C: Quantification of CD11c+ and I-A^d+ cells is shown over time. Data are shown as mean±SD. An asterisk indicates that p<0.05, CD11c⁺Aire^+/− versus CD11c⁺Aire^−/−. The symbol, †, indicates that p<0.05, I-A^d+Aire^+/− versus I-A^d+Aire^−/−.