Effect of human hepatocyte growth factor on promoting wound healing and preventing scar formation by adenovirus-mediated gene transfer

Abstract

Objective: To evaluate the effects of hepatocyte growth factor (HGF) on the prevention of scar formation and the promotion of wound healing by gene transfer.

Methods: A total of 12 female New Zealand rabbits were used in this study. Rabbits were anesthetized with an intravenous injection of sodium pentobarbital, and identical wounds were made over the ventral surface of each ear. Five circular wounds, 7 mm in diameter, were created in each ear by excision through the skin to the underlying cartilage using sterile technique. After the surgical procedures, 10 of the rabbits were randomly allocated to five groups, with 2 rabbits in each group: Ad-HGF group 1, Ad-HGF group 2, Ad-HGF group 3, Ad-GFP (a reporter gene) group and the solvent group. Immediately after surgery, 6 x 10(7) pfu Ad-HGF, 6 x 10(8) pfu Ad-HGF, 6 x 10(9) pfu of Ad-HGF, 6 x 10(9) pfu of Ad-GFP, or same volume of solvent (PBS, pH 7.2) was applied once to each wound in groups 1 to 5, respectively. One additional rabbit was used to evaluate the transfer efficiency of the adenovirus vector by transferring Ad-GFP (6 x 10(9) pfu) into its wounds. Ice slides of wounds from this animal were observed under fluorescence microscopy. Another additional rabbit was used to evaluate the expression of HGF and TGFbeta1 after transferring Ad-HGF (6 x 10(9) pfu) into each of its wound. Immunohistochemistry was used for detection.

Results: The effect of HGF on reducing excessive dermal scarring was observed by adenovirus-mediated gene transfer. Transfection of the human HGF cDNA into skin wounds through an adenoviral vector suppressed the over-expression of TGFbeta1, which plays an essential role in the progression of dermal fibrogenesis. Application of HGF to the wounds significantly enhanced wound healing and inhibited over scarring.

Conclusion: HGF gene therapy could be a new approach for preventing excessive dermal scarring in wound healing.