title: Cryopreservation of whole adipose tissue for future use in regenerative medicine.
abstract: BACKGROUND
  Human adipose tissue (AT) is an ideal stem cell source for autologous cell-based therapies. The preferred setting for tissue engineering and regenerative medicine applications is the availability of clinically acceptable off-the-shelf cells and cell products. As AT is not always available for use, cryopreserved tissue represents an alternative approach. The aim of the present study was to compare the different properties of mesenchymal stem cells (MSCs) isolated from cryopreserved AT. We have measured cell recovery, viability, phenotype, proliferative potential, and differentiation into mesenchymal (adipogenic, osteogenic, chondrogenic) and nonmesenchymal (neuron-like cells) lineages.
  
  
  METHODS
  AT (n = 10) was harvested from donors and either processed fresh or cryopreserved in liquid nitrogen dewars. Both fresh and thawed tissues were enzymatically digested. MSCs were analyzed by fluorescence-activated cell sorting for CD3, CD14, CD19, CD34, CD44, CD45, CD73, CD90, and CD105 expression. Growth characteristics of both groups were investigated for population doublings, doubling time, saturation density, and plating efficiency. MSCs derived from fresh and thawed tissues were assessed for differentiation potential both qualitatively and quantitatively.
  
  
  RESULTS
  Adherent cells from fresh and thawed tissues displayed similar fibroblastic morphology. Cryopreservation did not alter expression of phenotypic markers. Similarly, the proliferative potential of MSCs was not compromised by cryopreservation. Furthermore, cryopreservation did not alter the differentiation capability of MSCs as determined with histochemistry, immunofluorescence, and real time reverse transcriptase-polymerase chain reaction.
  
  
  CONCLUSIONS
  We conclude that human AT could be successfully cryopreserved for future clinical application and the recovered MSCs were equivalent in functionality to the freshly processed MSCs.
authors.affiliation: Department of Pathology, Advanced Centre of Research in Biomedical Sciences, King Edward Medical University, Lahore, Pakistan; Department of Immunobiology, College of Medicine, The University of Arizona, Tucson, Arizona.
authors.forename: Mahmood S
authors.initials: MS
authors.lastname: Choudhery
authors.affiliation: Department of Immunobiology, College of Medicine, The University of Arizona, Tucson, Arizona.
authors.forename: Michael
authors.initials: M
authors.lastname: Badowski
authors.affiliation: Department of Immunobiology, College of Medicine, The University of Arizona, Tucson, Arizona.
authors.forename: Angela
authors.initials: A
authors.lastname: Muise
authors.affiliation: Aesthetic Surgery of Tucson, Tucson, Arizona.
authors.forename: John
authors.initials: J
authors.lastname: Pierce
authors.affiliation: Department of Immunobiology, College of Medicine, The University of Arizona, Tucson, Arizona. Electronic address: davidh@email.arizona.edu.
authors.forename: David T
authors.initials: DT
authors.lastname: Harris
mesh_terms: D017667:Adipocytes / Q000166:cytology; D000273:Adipose Tissue / Q000166:cytology*; D053687:Adult Stem Cells / Q000166:cytology*; D002454:Cell Differentiation; D049109:Cell Proliferation; D002470:Cell Survival; D016922:Cellular Senescence; D019902:Chondrocytes / Q000166:cytology; D015925:Cryopreservation / Q000379:methods*; D006801:Humans; D016130:Immunophenotyping; D015187:Lipectomy; D059630:Mesenchymal Stem Cells / Q000166:cytology*; D009474:Neurons / Q000166:cytology; D010011:Osteocytes / Q000166:cytology; D044968:Regenerative Medicine / Q000379:methods*
keywords: Adipose tissue; Cryopreservation; MSC; Regenerative medicine; Tissue engineering