Replacement of full-thickness burns on mice with isogeneic skin equivalents

A copper slug heated with a soldering iron was used to produce full- and partial-thickness burns on the backs of mice. The untreated partial-thickness burns healed by outgrowth of epidermal cells from the hair follicles and adjoining skin, and the full-thickness burns formed linear scars. Skin equivalents containing isogeneic fibroblasts and epidermal cells were used to replace full-thickness burns; these grafts were fully vascularized and covered with a cornified epidermis within 2 weeks. The grafts maintained 34% of their original area at 180 days, but the full-thickness burns retained only 4.5% of the initial area. For the first 2 weeks, the splenic index in animals that received burns followed by surgical excision and grafting was significantly greater than in the animals that had burns not followed by excision, but the difference was no longer significant by 21 days.