Fig. 4. Impaired re-epithelialisation in K5ß1-null mice. Haematoxylin and Eosin staining of sections from 1-day wounds reveals similar histology between wounds of control (A) and K5ß1-null (B) mice (arrows indicate the epithelial margin). By 5 days post-wounding, 60% of wounds to control mice had re-epithelialised, with the hyperproliferative epithelium clearly covering the wound bed (C), whereas those of their K5ß1-null littermates (D) had never closed, with the hyperproliferative epithelium remaining almost static at the wound margins (n=10 for each). The tissue covering the wound bed in D is eschar, which will eventually be shed when the epithelial fronts meet several days later. D, dermis; E, epidermis; Es, eschar; F, fatty tissue; G, granulation tissue; HE, hyperproliferative epithelium; HF, hair follicle; M, muscle. Scale bars: 200 µm.