Bone marrow-derived stem cells in wound healing: a review.

Optimum healing of a cutaneous wound requires a well-orchestrated integration of the complex biological and molecular events of cell migration and proliferation, and of extracellular matrix deposition and remodeling. Several studies in recent years suggest that bone marrow derived stem cells such as mesenchymal stem cells, progenitor cells such as endothelial progenitor cells and fibrocytes may be involved in these processes, contributing to skin cells or releasing regulatory cytokines. Stem/progenitor cells may be mobilized to leave the bone marrow, home to injured tissues and participate in the repair and regeneration. Direct injection of bone marrow derived mesenchymal stem cells or endothelial progenitor cells into injured tissues shows improved repair through mechanisms of differentiation and/or release of paracrine factors. Enhanced understanding of these cells may help develop novel therapies for difficult cutaneous conditions such as non-healing chronic wounds and hypertrophic scarring as well as engineering cutaneous substitutes.