Debrided skin as a source of autologous stem cells for wound repair

Major traumatic injuries to the body, such as large surface area burns, limit the availability of autologous stem cell populations for wound repair. This report demonstrates that even after severe burn trauma to the body, resident stem cells present within the subcutaneous adipose tissue survive and are available for therapeutic uses. Debrided skin from wounded areas contains subcutaneous adipose tissue and can yield approximately 1.5 × 10(5) to 2.5 × 10(5) cells per milliliter of tissue. This observation indicates that tissue, which is normally discarded, could be a valuable source of stem cells. Initial immunohistochemistry of the debrided tissue localized platelet-derived growth factor receptor beta(+) (PDGFR-β(+) ) cells to perivascular niches of vascular beds. It was immunophenotypically confirmed that the cell isolates are stem cells and designated as debrided skin adipose-derived stem cells (dsASCs). Gene expression analysis of stem cell specific transcripts showed that the dsASCs maintained their stemness over serial passages. Furthermore, dsASCs were able to differentiate into adipogenic, osteogenic, and vascular cell lineages. Finally, an in vivo excision wound model in athymic rats demonstrated that the dsASCs are engrafted within a wound bed after 12 days. These data provide the first evidence that subcutaneous adipose tissue from discarded burned skin contains a viable population of stem cells that can be used for wound repair and skin regenerative therapies.