epidermis

Split-thickness grafts that contain mostly epidermis with only some of dermis can be used to cover larger areas, but they do not include features like hair and sweat glands, and are more prone to shrinkage and scarring.

"As alternatives to autologous skin grafts, artificial skin substitutes including cultured epidermis and reconstituted skins have been developed," says the lead author of the study Dr. Hisato Nagano.

"These options are inferior, though, as cultured epidermis can only be used for shallow wounds, and the engraftment rate of reconstituted skins is low."

To provide proof-of-concept for a new way to produce autologous skin grafts, the researchers generated skin grafts by introducing a mutation into mouse fetuses that made them unable to grow mature epidermis.

Intriguingly, injecting the same mutated mouse embryos with human skin cells yielded similar results: as the mice developed in utero, they grew sheets of human skin that mimicked the structure and organization of mature epidermis.