[Observation of the grafting of platelet-derived growth factor gene-modified artificial composite skin on rat wounds].

Objective: To observe the effects of the grafting of a platelet-derived growth factor gene-modified artificial composite skin on rat wounds with full thickness defect.

Methods: Platelet derived growth factor-B (PDGF-B) eukaryotic expression plasmid was constructed, and the fibroblasts were transfected with it by liposome mediation. Artificial composite skins 1 and 2 were constructed respectively. The skin1 was composed of keratinocyte, porcine acellular dermal matrix and PDGF-B gene-transfected fibroblasts while the skin 2 contained keratinocyte, porcine acellular dermal matrix and fibroblasts. The two kinds of composite skin were grafted onto wounds on the rat back to form composite skin group 1 (C1) and 2 (C2), respectively, with 18 rats in each group. Eight rats with wounds without treatment served as control (C) group. The survival rate of the composite skin was observed at 2 post-operative weeks (POWs). The rat wounds were examined grossly on 2, 4 and 6 POWs for the calculation of wound contraction rate. Wound tissue samples were harvested for histological examination.

Results: (1) Up to 2 POWs, 14 grafts in C1 group survived completely, 3 with partial survival and 1 failure. In C2 group, 10 skin grafts survived completely, 4 with partial survival and 4 failures. (2) A scab was formed in the wound at 2 POW in C group. The surface of the grafted skin in C1 group was smooth, elastic, and showed good anti-friction properly, and it was better in quality compared with that in other two groups at 6 POW. (3) The wound contraction rate of the grafts in C group of rats was higher than that in C1 and C2 groups at 2, 4 and 6 POWs, while that in C1 was lower than that in C2 group. (4) Capillary formation was more intense in the grafted skins in C1 group at 2 POWs, and the epithelia differentiated well into 7 to 10 layers of epithelial cells with compact and orderly arrangement and evenly distributed fibrous tissue at 6 POWs.

Conclusion: Repair of the wound with artificial composite skin containing PDGF-B gene could improve the quality of wound healing.