title: Engineering of adipose tissue by injection of human preadipocytes in fibrin.
abstract: BACKGROUND
  Despite efforts of plastic surgeons in recent years to discover new alternatives, the techniques currently used for restoration of soft tissue defects still have disadvantages. The gold standard for soft tissue reconstruction remains autologous pedicled/free tissue transfer. This technique often results in high rates of operative morbidity and donor site deformity. Results obtained by autologous fat tissue transfer usually are disappointing because of a high graft resorption rate with unpredictable outcomes. Different tissue engineering approaches have been used in the past to generate adipose tissue. However, long-term results in terms of volume persistence have been disappointing.
  
  
  METHODS
  In this study, different concentrations of undifferentiated human preadipocytes in fibrin were injected into athymic nude mice (n = 8). Mice that had fibrin injection without cells served as control subjects (n = 8). The specimens were explanted after 1, 2, 6, and 9 months, with subsequent qualitative and quantitative analysis of adipose tissue formation by histologic and image analysis.
  
  
  RESULTS
  Within the first 4 weeks after initial volume reduction of the implants, the volume and shape of the implants with preadipocytes remained stable. The implants without cells were completely resorbed within 3 weeks. Histologic analysis demonstrated generation of stable adipose tissue with no signs of an inflammatory response or evidence of tissue necrosis in the implants containing preadipocytes. The best results were obtained after implantation of 30 million preadipocytes. Adipose tissue formation was not observed in the control group.
  
  
  CONCLUSIONS
  The findings demonstrate that long-term stable adipose tissue can be engineered in vivo by simple injection of human preadipocytes using fibrin as a carrier material. After further investigation, this approach may represent an alternative to the techniques currently used for soft tissue restoration.
authors: Department of Plastic and Hand Surgery, University of Freiburg Medical Center, Freiburg, Germany. nestorbo70@hotmail.com
authors: Nestor
authors: N
authors: Torio-Padron
authors: Niklas
authors: N
authors: Baerlecken
authors: Arash
authors: A
authors: Momeni
authors: G Bjoern
authors: GB
authors: Stark
authors: Joerg
authors: J
authors: Borges
mesh_terms: D017667:Adipocytes / Q000378:metabolism / Q000637:transplantation*; D050156:Adipogenesis; D000273:Adipose Tissue / Q000378:metabolism*; D000818:Animals; D002454:Cell Differentiation; D002478:Cells, Cultured; D015718:Fibrin Tissue Adhesive / Q000378:metabolism*; D005346:Fibroblast Growth Factors / Q000378:metabolism; D005786:Gene Expression Regulation; D020007:Implants, Experimental; D051379:Mice; D008819:Mice, Nude; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D023822:Tissue Engineering / Q000379:methods*
chemical_list: D015718:Fibrin Tissue Adhesive; D012333:RNA, Messenger; D005346:Fibroblast Growth Factors