Accelerated adhesion of grafted skin by gene transfer of hepatocyte growth factor (HGF) ; application of laser-induced stress waves

Hepatocyte growth factor (HGF) is a pleiotropic growth factor, which is involved in cell proliferation, cell migration, antiapoptosis, morphogenesis and an-giogenesis. We delivered the hHGF gene to rat free skin grafts using laser-induced stress waves (USWs) with the objective of accelerating adhesion of the grafts. After delivering plasmid DNA to skin grafts, autografting was performed with the grafts, angiogen-esis, cell proliferation and reepithelialization were evaluated based on immunohistochemistry and reper-fusion was measured by laser Doppler imaging as a function of time after grafting. It was found that angio-genesis on Day 3 after grafting and the increasing ratio of blood flow on Day 4 to that on Day 3 were significantly enhanced compared with those of control groups. Reepithelialization was almost completed on Day 7 even at the center of the graft with LJSW application after hHGF gene injection, while it was not for the grafts of the control groups. These findings demonstrate the validity of our LISW-based HGF gene transfection to accelerate the adhesion of grafted skin.