BACKGROUNDThe authors examined the efficacy of adipose stem cells, when supplied either alone or in platelet-rich fibrin gels, to improve wound healing.METHODSA porcine full-thickness wound model was used to compare six topical treatments: platelet-poor plasma; platelet-rich plasma; autologous adipose stem cells plus platelet-poor plasma; autologous adipose stem cells plus platelet-rich plasma; allogeneic adipose stem cells containing green fluorescent protein plus platelet-poor plasma; and saline (control). One week after isolation, adipose stem cells were applied to full-thickness wounds on the paraspinal and thoracic regions of three pigs (44 wounds per pig; each treatment was applied to eight separate wounds). Each wound was monitored over 21 days for closure, cosmesis, and histopathology.RESULTSThere was no significant difference in the reepithelialization rate, but treatments containing adipose stem cells demonstrated increased microvessel densities (31.75 +/- 5.73 vessels/cm2 versus 7.93 +/- 3.61 vessels/cm2) compared with groups without adipose stem cells. Wound cosmesis was improved in the adipose stem cell plus platelet-rich plasma group compared with other treatment groups (p < 0.05). Vascular endothelial growth factor levels detected in matrices containing adipose stem cells were approximately 7-fold higher compared with platelet-rich plasma or platelet-poor plasma (p < 0.05). Localization of transgenic green fluorescent protein plus adipose stem cells indicated incorporation near neovasculature.CONCLUSIONSIn normal healing wounds, adipose stem cells appear to enhance the healing process only when provided in a fibrin gel vehicle containing a number of complementary wound-healing trophic factors. Perivascular adipose stem cell localization suggests a function in enhancing blood supply through providing physical and paracrine support to newly forming vessels.