Mesenchymal stem cell-conditioned medium accelerates wound healing with fewer scars.

Mesenchymal stem cells (MSCs) derived from umbilical cords (UC-MSCs) have been shown to enhance cutaneous wound healing by means of the paracrine activity. Fibroblasts are the primary cells involved in wound repair. The paracrine effects of UC-MSCs on dermal fibroblasts have not been fully explored in vitro or in vivo. Dermal fibroblasts were treated with conditioned media from UC-MSCs (UC-MSC-CM). In this model, UC-MSC-CM increased the proliferation and migration of dermal fibroblasts. Moreover, adult dermal fibroblasts transitioned into a phenotype with a low myofibroblast formation capacity, a decreased ratio of transforming growth factor-β1,3 (TGF-β1/3) and an increased ratio of matrix metalloproteinase/tissue inhibitor of metalloproteinases (MMP/TIMP). Additionally, UC-MSC-CM-treated wounds showed accelerated healing with fewer scars compared with control groups. These observations suggest that UC-MSC-CM may be a feasible strategy to promote cutaneous repair and a potential means to realise scarless healing.