Influence of vascularized transplant bed on fat grafting

Recent advances in regenerative medicine have opened up the option of materials used for transplantation. However, only a few studies have examined the take of transplanted tissues. We attempted to establish a functional bed for transplanted tissues using growth factors. A cylinder-type silicone substrate (spacer) was coated with a photoreactive gelatin containing basic fibroblast growth factor. This spacer was transplanted into the dorsal subdermal layer in a rabbit. After 2 and 4 weeks, the capsule formed around the spacer was histologically assessed for use as a transplant bed. In addition, after 2-4 weeks of spacer grafting, autologous fat was transplanted into the capsule. After 4 more weeks, the grafted fat was assessed immunohistochemically to evaluate the capsule as a functional bed for transplantation. In the groups pretreated with growth factors, proliferation of blood vessels was observed in the capsules. After fat grafting, a pattern of overall necrosis was observed in controls. However, good proliferation of blood vessels and favorable fat take were observed in the groups pretreated with growth factors. Necrosis, however, was found at the center of the grafted fat. We conclude that a vascularized transplant bed was useful for promoting take of the grafted fat.