[Effects of hVEGF cDNA on random skin flap via a replication-deficient adenovirus vector]

The purpose of this study was to determine the effects of local delivery of vascular endothelial growth factor( VEGF) transferred with adenovirus-mediated gene on the survival of ischemic random skin flap in rats.

The animals were divided into three groups randomly (n = 10) . A 2 cm x 8 cm dorsal skin flap was designed with the pedicle at the level of the iliac crest. In group A (AdCMV-VEGF), each animal received 10(12) PR replication-deficient recombinant adenovirus (AdCMV-VEGF) in the distal two-thirds of the proposed flap by means of the subdermal injection at ten different locations. In group B (AdCMV-GaI), each received 1012 PR AdCMV-Gal. In Group C (Saline), each received 1 ml saline. Three days after the treatment, the flap was elevated as planed way and re-sutured back to its donor site. All the animals were evaluated 7 days after the operation.

The mean percentage of surviving flap area was (85.91 +/- 2.54)% in group A, (59.56 +/- l.18)% in group B, and (61.48 +/- l.09)% in group C. There was a significant increase in the percentage of the survival area in the flaps of the group A, compared with the group B and group C (Group B vs. Group A, P < 0.01; Group C vs.Group A, P < 0.01, Group B vs. Group C, P >0.05). Hybridization in the situ, the immunohistochemical stain showed that the VEGF was expressed in the survival tissue of the flap treated with the AdCMV-VEGF, but it was not found in the control groups. Histological analysis demonstrated qualitatively greater amount of granulation tissue and angiogenesis was found in the group treated with the AdCMV-VEGF than the controls.

The results may indicate that Ad vector carrying VEGF cDNA could be useful in enhancing the survival of the skin flap due to the effect of the local delivery of the VEGF.