Mast cells could actually inhibit wound healing.

Even when it comes to wound healing, it seems there can be too much of a good thing.

Recovery can be delayed when the body produces too many mast cells, which are normally helpful. At least, that’s according to an article published in the July issue of the Journal of Leukocyte Biology.

Investigators found that an overabundance of these cells also leads to the overproduction of IL-10, which prevents certain white blood cells from reaching the wounded area. The work involved mice with lymphedematous skin, and could eventually provide better treatments for human skin ulcers in the lower extremities.

“Improvement of lymphedema is important for treatment of skin ulcers,” said Makoto Sugaya, M.D., Ph.D., a researcher involved in the work from the Department of Dermatology at the University of Tokyo. “It is not just fluid retention, but inflammatory cells and cytokines that cause delayed wound healing.”

To make this discovery, scientists used two groups of mice. The first showed severe lymphatic dysfunction; the second was normal. Researchers administered skin wounds and found that the mice with lymphatic dysfunction showed delayed wound healing. Analysis showed that the delayed wound healing in the lymphedematous skin was the result of too many mast cells and elevated IL-10 expression, both of which can now be therapeutic targets for future drug development.