Figure 3: Main strategies using stem cells and their fate. Mesenchymal stem cells (MSC) could favor tissue repair and wound healing via direct injection in injury site, systemic injection, conditioned media using and biomaterials. The biological processes implied in wound repair, transdifferentiation and cytokines/ trophic factors release, depend on administrated products. Transdifferentiation of MSC has been reported into fibroblast, endothelial cells and keratinocytes [40]. Transdifferentiation of MSC to proliferative basal keratinocytes is observed in presence of β-catenin [43], bone-morphogenic protein 4 (BMP4), and epithelial growth factor (EGF) [42]. The differentiation of basal keratinocytes to mature keratinocytes is based on Ca2+ gradient and the presence of Wnt 4-5- 10b in extra-cellular matrix [156].