Human keratinocytes grown at a gas-permeable interface in vitro stratify correctly to generate engineered human epidermis.

Abstract

One of the key functions of human skin is to provide a barrier, protecting the body from the surrounding environment and maintaining homeostasis of the internal environment. A mature, stratified epidermis is critical to achieve skin barrier function and is particularly important when producing skin grafts in vitro for wound treatment. For decades epidermal stratification has been achieved in vitro by culturing keratinocytes at an air-liquid interface, triggering proliferating basal keratinocytes to differentiate and form all epidermal layers. We show here that culturing keratinocytes at a gas-permeable interface can induce epidermal stratification equivalent to an air-liquid interface. Culturing skin grafts at a gas-permeable interface has a number of advantages over the traditional air-liquid interface method including: less time input from highly skilled personnel, with consequent cost savings; fewer manipulations, with concomitant reduced risk of cell culture contamination; increased scalability of skin graft size; and improved potential for automation. These advantages confer significant benefits to the use of cell culture devices with gas-permeable interfaces to grow human skin for the treatment of major burns and other skin injuries.