A new technique using human embryonic stem cells may enable doctors to grow “replacement skin” that can be used to help treat burn victims, according to research published this week in the British medical journal The Lancet. Doctors have been using burn patients’ own cells to grow new skin to repair injuries for more than two decades. Yet, while the technique using these autologous grafts (or basically grafts provided by your own body) has proven effective, the long delay in growing the skin—it generally takes three weeks—can expose the burn patient to increased risk for infection and dehydration. To buy the patients’ time while the new skin is grown, doctors largely rely on grafts from cadavers, yet these run the risk of rejection due to potential immune reaction. To overcome this problem, researchers have long been working to develop other temporary skin replacement materials, but even the best existing remedies—synthetic skin grafts, or those that include cells from cows or other humans—run the risk of being quickly rejected by patients’ bodies, or even introducing disease.
Yet this latest technique—in which, to oversimplify some, researchers duplicated the biological process through which stem cells become skin cells—may enable physicians to have access to an unlimited supply of temporary skin replacements, without the high risk for rejection. To grow the skin grafts, researchers began by growing human embryonic stem cells in vitro for 40 days using “feeder cells” from mice. After this, the cells were transferred onto a “matrix” or framework of artificial material, before being transplanted onto the backs of mice. Within 12 weeks of transplantation, the skin grown on mice was structurally consistent with human skin. As the researchers write, “Growing human epidermis from [human embryonic stem cells] could have clinical relevance as an unlimited resource for temporary skin replacement in patients with large burns awaiting autologous grafts.”
The next step in research, of course, is to trial the technique in a human population. And, beyond that, the study’s authors say, they hope to determine whether the growth period using this technique could be extended, enabling scientists to grow bigger skin grafts, and potentially even develop methods for using these grafts as more permanent transplants for patients unable to grow new skin from their own cells.