Survival of Autologous Fat Grafts in Humans and in Mice

Autologous fat grafts have been used in a number of surgical procedures, yet properties of fat as a transplant material have remained unclear. This study was designed to compare experimental observations of subcutaneous fat grafts in mice with clinical observations of autologous fat grafts placed over the dura following laminectomy in humans. Subcutaneous fat grafts were observed daily in 75 CFI mice with the use of modified Algire back chambers. Grafts were examined histologically and histochemically at intervals up to 60 days after transplantation. Gross and microscopic observations suggest that fat grafts went through a period of initial breakdown of fat cells which was followed by revascularization. This resulted in normal appearing fat, although a smaller volume than the original graft. Three samples of autologous fat grafts from humans were removed during reoperation in the lumbar region up to 22 months after the original procedure. Histological examination revealed revascularized grafts reduced in size: the fat was normal and never replaced by scar tissue.