Supernatants from cultured human epidermal keratinocytes stimulate angiogenesis

Conditioned media from three different strains of human epidermal keratinocytes in culture were assayed on the chorioallantoic membrane of the chick embryo. Vascular responses were examined 4 days later stereo-microscopically and compared with controls--unconditioned medium and medium incubated with 3T3 cells. Specimens were also collected after 1, 2, 3 and 4 days for serial histological examination. Media from all three strains of keratinocytes stimulated statistically significant vascular growth relative to controls. Leukocytic infiltration was not demonstrated histologically at any time. In addition, quantitation of ectodermal epithelial hyperplasia in experimental groups did not reveal any significant difference when compared with controls. These results have demonstrated that epidermis may directly encourage vascular growth in the absence of significant inflammation.