By transforming the most common type of cells found in wounds into fat cells, researchers have reported finding a way to manipulate wounds to heal as regenerated skin rather than scar tissue. "Essentially, we can manipulate wound healing so that it leads to skin regeneration rather than scarring," said principal investigator George Cotsarelis, Professor of Dermatology at Perelman School of Medicine at the University of Pennsylvania, US.Fat cells called adipocytes are normally found in the skin, but they are 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."The secret is to regenerate hair follicles first. After that, the fat will regenerate in response to the signals from those follicles," Cotsarelis said.
The study showed hair and fat develop separately but not independently. Hair follicles form first, and the Cotsarelis lab previously discovered factors necessary for their formation. The new study - published online in the journal Science - details additional factors actually produced by the regenerating hair follicle to convert the surrounding myofibroblasts to regenerate as fat instead of forming a scar. As they examined the question of what was sending the signal from the hair to the fat cells, researchers identified a factor called Bone Morphogenetic Protein (BMP). It instructs the myofibroblasts to become fat. "Typically, myofibroblasts were thought to be incapable of becoming a different type of cell," Cotsarelis said. "But our work shows we have the ability to influence these cells, and that they can be efficiently converted into adipocytes," Cotsarelis noted.This was shown in both the mouse and in human keloid cells grown in culture."The findings show we have a window of opportunity after wounding to influence the tissue to regenerate rather than scar," said the study's lead author Maksim Plikus, Assistant Professor at University of California, Irvine. The findings could lead to new therapies to help wounds heal without scarring.