The method involves transforming the most common type of cells found in wounds into fat cells – something that was previously thought to be impossible in humans. Researchers began this work at the Perelman School of Medicine at the University of Pennsylvania, which led to a large-scale, multi-year study in connection with the Plikus Laboratory for Developmental and Regenerative Biology at the University of California, Irvine. They published their findings online in the journal Science on Thursday, January 5th, 2017.

Fat cells called adipocytes are normally found in the skin, but they're lost when wounds heal as scars. The most common cells found in healing wounds are myofibroblasts, which were thought to only form a scar. Scar tissue also does not have any hair follicles associated with it, which is another factor that gives it an abnormal appearance from the rest of the skin. Researchers used these characteristics as the basis for their work – changing the already present myofibroblasts into fat cells that do not cause scarring.

"Essentially, we can manipulate wound healing so that it leads to skin regeneration rather than scarring," said George Cotsarelis, MD, the chair of the Department of Dermatology and the Milton Bixler Hartzell Professor of Dermatology at Penn, and the principal investigator of the project. "The secret is to regenerate hair follicles first. After that, the fat will regenerate in response to the signals from those follicles."