title: Cryopreservation of human fat for soft tissue augmentation: viability requires use of cryoprotectant and controlled freezing and storage.
abstract: BACKGROUND
  Autologous fat transfer for soft tissue augmentation has been increasing in recent years. Graft longevity may vary greatly from patient to patient, requiring repeat procedures, often using frozen adipose tissue. Storage usually involves placing syringes of fat directly into a -20 degrees C freezer. However, the viability of fat frozen in this way is controversial.
  
  
  OBJECTIVE
  This study tested methods for the optimal storage of adipose tissue harvested by tumescent liposuction.
  
  
  METHODS
  Aliquots of washed adipose tissue were frozen directly at -20 degrees C or mixed with cryoprotectants, frozen at 1 degree C/min, and subsequently stored in liquid nitrogen vapor phase. Aliquots were subsequently thawed, and adipocyte viability was determined by staining and culture methods.
  
  
  RESULTS
  Viability of adipocytes frozen at -20 degrees C was very low when analyzed by staining, and no cultures could be established from any of the specimens. In contrast, viable adipocytes were recovered from samples that were controlled-rate frozen in the presence of cryoprotectants and stored in nitrogen vapor. CONCLUSION. Our results indicate that fat frozen at -20 degrees C is not viable and thus provides no advantage over inert fillers. The methods here described could readily be transferred to the clinical setting after further laboratory study.
authors.affiliation: Differentiated Cell Laboratory, Coriell Institute for Medical Research, 403 Haddon Avenue, Camden, NJ 08103, USA. dmoscate@cimr.umdnj.edu
authors.forename: David K
authors.initials: DK
authors.lastname: Moscatello
authors.forename: Megan
authors.initials: M
authors.lastname: Dougherty
authors.forename: Rhoda S
authors.initials: RS
authors.lastname: Narins
authors.forename: Naomi
authors.initials: N
authors.lastname: Lawrence
mesh_terms: D017667:Adipocytes / Q000502:physiology; D000273:Adipose Tissue / Q000637:transplantation*; D000328:Adult; D015925:Cryopreservation / Q000379:methods*; D003451:Cryoprotective Agents; D005260:Female; D005615:Freezing; D006801:Humans; D008297:Male; D008875:Middle Aged; D012034:Refrigeration; D015361:Rhytidoplasty / Q000379:methods*; D014182:Transplantation, Autologous
chemical_list: D003451:Cryoprotective Agents