Transdermal delivery of adipocyte-derived stem cells using a fractional ablative laser.

BACKGROUND: Chronic wound healing problems can pose a significant clinical challenge. Transdermal delivery of adipose-derived stem cells (ADSC) may be a possible solution to healing these recalcitrant, debilitating wounds. Pretreatment of the skin with a fractionated laser has already been shown to assist transdermal drug delivery both in vitro and in vivo and may be an ideal approach to facilitating delivery of ADSC to the target tissue. OBJECTIVES: The authors investigate in a porcine model whether ADSC can be delivered transdermally following pretreatment with a fractional laser. METHODS: After ethics approval was obtained, the abdomens of 2 adult female domestic pigs were pretreated with an erbium:YAG fractionated ablative laser. Following laser treatment, 20 × 10(6) bromodeoxyuridine (BrdU)-labeled ADSC were applied topically to the first animal for 4 hours. The same number of BrdU-labeled ADSC was applied to the second animal for 48 hours. The animals were euthanized at the end of their respective treatment periods, and the BrdU-labeled ADSC were counted after tissue harvest. RESULTS: At 4 hours, an average of 2.40 × 10(6) cells, or 12.0% of the total cells applied, were found in the tissue. At 48 hours, an average of 1.1 × 10(6) cells, or 5.5% of the total cells applied, were seen. CONCLUSIONS: This pilot study demonstrates that ADSC can be delivered transdermally through skin that has been pretreated with a laser. Potential future applications of this approach might include wound-healing or aesthetic indications. Further studies need to be conducted to determine the optimal number of ADSC to use in this approach, the best methods of application, and the effect of transdermally delivered ADSC on wound healing.