title: The Relationship of a Combination of Human Adipose Tissue-Derived Stem Cells and Frozen Fat with the Survival Rate of Transplanted Fat.
abstract: BACKGROUND
  The survival rate of grafted fat is difficult to predict, and repeated procedures are frequently required. In this study, the effects of the freezing period of harvested adipose tissue and the addition of human adipose tissue-derived stem cells (ASCs) on the process of fat absorption were studied.
  
  
  METHODS
  Adipose tissue was obtained from patients who underwent a lipoaspirated fat graft. The fat tissue was cryopreserved at -20℃ in a domestic refrigerator. A total of 40 nude mice were used. The mice in the experimental group received three different subcutaneous injections in the back: an injection of fresh fat and ASCs, an injection of fat that had been frozen for one month and ASCs, and an injection of fat that had been frozen for two months and ASCs. The control mice received fat grafts without ASCs. The mice were sacrificed at four or eight weeks after the procedure, and the grafted fat tissues were harvested. The extracted fat was evaluated using photographic analysis, volume measurements, and histological examination.
  
  
  RESULTS
  In the control group, the fat resorption rates four weeks after transplantation in the grafts of fresh fat, fat that had been frozen for one month, and fat that had been frozen for two months were 21.14%, 22.46%, and 42.56%, respectively. In the experimental group, the corresponding resorption rates were 6.68%, 13.0%, and 33.9%, respectively.
  
  
  CONCLUSIONS
  ASCs can increase the fat graft survival rate. The use of ASCs in fat grafting can reduce the need for repeated fat grafts and provide good long term results.
authors.affiliation: Daisy Plastic Surgery Clinic, Seongnam, Korea.
authors.forename: Ki-Young
authors.initials: KY
authors.lastname: Ha
authors.affiliation: Department of Plastic Surgery, Korea University Anam Hospital, Korea University College of Medicine, Seoul, Korea.
authors.forename: Hojin
authors.initials: H
authors.lastname: Park
authors.affiliation: Department of Plastic Surgery, Korea University Anam Hospital, Korea University College of Medicine, Seoul, Korea.
authors.forename: Seung-Ha
authors.initials: SH
authors.lastname: Park
authors.affiliation: Department of Plastic Surgery, Korea University Anam Hospital, Korea University College of Medicine, Seoul, Korea.
authors.forename: Byung-Il
authors.initials: BI
authors.lastname: Lee
authors.affiliation: Department of Plastic Surgery, Korea University Ansan Hospital, Korea University College of Medicine, Seoul, Korea.
authors.forename: Yi-Hwa
authors.initials: YH
authors.lastname: Ji
authors.affiliation: Department of Plastic Surgery, Bundang Jesaeng General Hospital, Seongnam, Korea.
authors.forename: Tae-Yeon
authors.initials: TY
authors.lastname: Kim
authors.affiliation: Department of Plastic Surgery, Korea University Anam Hospital, Korea University College of Medicine, Seoul, Korea.
authors.forename: Eul-Sik
authors.initials: ES
authors.lastname: Yoon
keywords: Adipose tissue; Cryopreservation; Injections, subcutaneous; Stem cells