Figure 2.

Keratinocyte proliferation. Tissue sections of normal, unwounded skin (A, inset), normal 2-day excisional wound (A), and ulcer tissue from two patients with diabetes (B,C). Approximately 10% of the basal keratinocytes population immunostain with Ki67. Ki67 immunostaining is absent in the actively migrating tongue (outlined by the dotted line) of a normal, 2-day excisional acute wound; however, it is present in basal keratinocytes in the epidermal region behind the migrating tongue. Tissue sections of ulcers from two patients with diabetes shows strong numbers of Ki67-immunolabeled keratinocytes at the margin of the ulcer edge and a great distance from the ulcer edge (B,C). Top arrow indicates direction of epidermal migration, small arrows in A indicate Ki67-immunostained keratinocytes, and arrowheads in A–C indicate migrating tongue. Bars: A = 50 μm; B,C = 100 μm.