Fig. 4.

Immunohistochemical detection of neutrophils (myeloperoxidase-positive) and macrophages (F4/80-labeled) in a healing wild-type (WT) or a TRPV1-null (KO) mouse incision-injured cornea. Infiltration of myeloperoxidase-expressing neutrophils was not obviously observed in injured healing tissue of both WT (a, c) and KO (b, d) mice at day 5 (a, b) and 10 (c, d). Macrophage invasion was also evaluated by immunohistochemistry for F4/80 antigen. At day 5, abundant F4/80-labeled macrophages were detected in the granulation tissue formed in the wound of a WT mouse (e), while very few immune-labeled cells were seen in a KO cornea (f). At day 10, macrophage invasion was much reduced in the stroma of both genotypes of mice (g, h). Frames (a’–h’) indicate the boxed areas of each frames that indicate the higher magnification pictures of the immune-labeled cells in the stroma. epi epithelium, st stroma, arrows at the site of the original injury. Bar 100 μm. Real-time RT-PCR does not show difference of the expression of F4/80 macrophage antigen between two genotypes in an uninjured cornea as well as that at day 3 post-injury (i)