title: Long-term stability of adipose tissue generated from a vascularized pedicled fat flap inside a chamber.
abstract: BACKGROUND
  Numerous studies demonstrate the generation and short-term survival of adipose tissue; however, long-term persistence remains elusive. This study evaluates long-term survival and transferability of de novo adipose constructs based on a ligated vascular pedicle and tissue engineering chamber combination.
  
  
  METHODS
  Defined adipose tissue flaps were implanted into rats in either intact or perforated domed chambers. In half of the groups, the chambers were removed after 10 weeks and the constructs transferred on their vascular pedicle to a new site, where they were observed for a further 10 weeks. In the remaining groups, the tissue construct was observed for 20 weeks inside the chamber. Tissue volume was assessed using magnetic resonance imaging and histologic measures, and constructs were assessed for stability and necrosis. Sections were assessed histologically and for proliferation using Ki-67.
  
  
  RESULTS
  At 20 weeks, volume analysis revealed an increase in adipose volume from 0.04 ± 0.001 ml at the time of insertion into the chambers to 0.27 ± 0.004 ml in the closed and 0.44 ± 0.014 ml in the perforated chambers. There was an additional increase of approximately 10 to 15 percent in tissue volume in flaps that remained in chambers for 20 weeks, whereas the volume of the transferred tissue not in chambers remained unaltered. Histomorphometric assessment of the tissues documented no signs of hypertrophy, fat necrosis, or atypical changes of the newly generated tissue.
  
  
  CONCLUSIONS
  This study presents a promising new method of generating significant amounts of mature, vascularized, stable, and transferable adipose tissue for permanent autologous soft-tissue replacement.
authors: Fitzroy and Melbourne, Victoria, and St. Lucia and Brisbane, Queensland, Australia From The O'Brien Institute; the Departments of Surgery, Anatomical Pathology, and Medical Imaging, St. Vincent's Hospital; the Australian Institute for Bioengineering and Nanotechnology, University of Queensland; the Institute of Health and Biomedical Innovation, Queensland University of Technology; and the Department of Chemical and Biomolecular Engineering, University of Melbourne.
authors: Juergan H
authors: JH
authors: Doldere
authors: Erik W
authors: EW
authors: Thompson
authors: John
authors: J
authors: Slavin
authors: Nicholas
authors: N
authors: Trost
authors: Justin J
authors: JJ
authors: Cooper-White
authors: Yang
authors: Y
authors: Cao
authors: Andrea J
authors: AJ
authors: O'Connor
authors: Anthony
authors: A
authors: Penington
authors: Wayne A
authors: WA
authors: Morrison
authors: Keren M
authors: KM
authors: Abberton
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