Skin equivalents containing allogeneic fibroblasts in a collagen matrix and overlaid with isologous epidermal cells have been successfully grafted to rodents. By contrast, skin equivalents containing isologous fibroblasts and allogeneic epidermal cells provoke a strong rejection response, characterized by the infiltration of mononuclear cells into the epidermis at 1 week and occlusion of the microvasculature and destruction of the epidermis by lymphocytes 2 weeks after grafting. Based on these findings, skin equivalents containing allogeneic fibroblasts could be used in the treatment of burn injuries, but the epidermis should be obtained from the patient.