[The effect of adipose-derived stem cells on viability of random pattern skin flap in rabbits]

To explore the effect of the adipose derived stem cells (ADSCs) on the survival of random pattern skin flap in rabbits.

ADSCs were isolated from fresh human fat and expanded in vitro for five passages. Then the characterization of ADSCs were determined by their CD marker profile and their ability to differentiate into osteogenic, adipogenic and chondrogenic lineages. On the back of the rabbits, two symmetric cephalic-based random pattern skin flaps were designed (6 cm x 2 cm). The right flaps were used as experimental groups with the contra-side flaps as control group. Human ADSCs were pre-labeled before seeding with fluorescent 3, 30-dioctadecyloxacarbocyanine perchlorate (DiO) dye. The experimental flaps evenly received 5-point injection of 2 x 10(6)Dio-labeled ADSCs resuspended in 0.5 ml of serum-free DMEM, while only 0.5 ml medium was injected into the control flaps. Seven days later, the survival rate of flaps was evaluated. The flaps underwent frozen section and were observed under the laser scanning confocal microscope to detect the fluorescence imaging. Flaps also underwent HE staining and were observed under light microscope to detect the vascular density.

Compared with control group, there was a significant increase of flap survival rate in the experimental group (P < 0.01). Histological analysis also demonstrated a statistically significant increase in capillary density in the experimental group.

It suggests that ADSCs have a better immune compatibility and potential for enhancing the blood supply of random pattern skin flaps.