An evaluation of the engraftment and the blood flow of porcine skin autografts inactivated by high hydrostatic pressure.

We previously reported that exposure to a high hydrostatic pressure (HHP) of 200 MPa could completely inactivate porcine skin without damaging the extracellular matrix. In this study, we used an autologous porcine skin graft model and explored whether the skin inactivated by HHP could be engrafted without inflammation to the residual cellular components. Twenty-one full-thickness skin grafts of 1.5 × 1.5 cm in size were prepared from a minipig (n = 2). Grafts were either nonpressurized or pressurized to 100, 150, 200, 300, 500, or 1000 MPa (n = 3) and randomly implanted on the fascia and removed at 1 and 4 weeks after grafting. All grafts showed complete engraftment at the macroscopic level and microcirculation was detected by a full-field laser speckle perfusion imager. The epidermis was removed and skin appendages were not observed in the grafts pressurized to more than 200 MPa. Azan and Elastica van Gieson staining showed no sign of dermal collagen fiber degeneration, while elastin fibers were observed. The fibroblasts and capillaries were observed to have infiltrated to dermis in all groups without severe inflammation. In conclusion, we showed that skin inactivated by HHP up to 1000 MPa could be engrafted successfully without removing cellular remnants.