Fig. 8. Histology of 15-day wounds reveals marked differences in the outcome of the repair process. Masson trichrome staining of 15-day wounds of control mice reveals complete re-epithelialisation (A). However, in several wounds of K5ß1-null mice, the epithelial tongues fail to fuse and detach from the underlying granulation tissue (B) and, where fusion does occur, the epidermis is far thicker than that seen in control mice (compare A with C). G, granulation tissue; HE, hyperproliferative epithelium. Scale bars: 200 µm.