Impaired migration of epidermal cells from decubitus ulcers in cell cultures. A cause of protracted wound healing?

Cultured epidermal cells of explants from decubitus ulcer edges showed significant (P less than 0.05) decreased maximal growth rate (range, 1.3-15.6%) and decreased area of outgrowth per explant (mean and SD, 1.6 +/- 1.7 mm2) when compared with explants obtained 4-5 cm distant from the ulcer edge (range, 46.7-68.8% and 4.6 +/- 2.7 mm2, respectively) and from healthy skin (range, 78.8-93.3% and 6.6 +/- 1.2 mm2, respectively). In contrast, epidermal cells in biopsies from the ulcer edge were significantly (P less than 0.05) more prevalent (range, 1.9-48.2%) as compared with biopsies of healthy skin (range, 3.1-5.1%). Therefore, the decreased growth rate and decreased area of outgrowth may be caused by a defective migration potential rather than an impaired mitotic activity. The latter seems to be normal, as demonstrated by the histomorphometry, which indicates the in vivo situation. Decreased migration potential of epidermal cells could explain the clinically observed protracted epithelialization of decubitus ulcers.