Long-term preservation of adipose aspirates after conventional lipoplasty

Background: Optimal cryopreservation permits the long-term storage of living cells or tissues that may have potential clinical applications. Unfortunately, there are no successful studies on the long-term preservation of adipose aspirates for possible autologous fat grafting. Objective: The purpose of the current study was (1) to test our hypothesis that adipose aspirates obtained from conventional lipoplasty could be preserved and stored at low temperature (below -85°C) by means of an optimal cryopreservation technique and (2) to develop a novel approach to effectively preserve adipose aspirates for future applications. Methods: The middle layer of adipose aspirates obtained from conventional lipoplasty was collected after centrifugation and each specimen was then randomized into 3 groups: the control group, fresh adipose aspirates without preservation; experimental group 1, simple cryopreservation with liquid nitrogen only; and experimental group 2, optimal cryopreservation with cryoprotective agents consisting of a combination of dimethyl sulfoxide (DMSO) and trehalose. Cryopreservation of adipose aspirates was conducted with controlled slow cooling and fast rewarming rates. Fresh or cryopreserved adipose aspirates in each group were evaluated by viable adipocyte counts, glycerol-3-phosphate dehydrogenase (G3PDH) assay, and routine histology. Results: Significantly more viable adipocytes and better cellular function of adipose aspirates were found in the experimental group 2 compared to the results in the experimental group 1. Conclusions: Our results indicated that an optimal cryopreservation approach that utilizes a combination of DMSO and trehalose as cryoprotective agents appears to provide good long-term preservation of adipose aspirates obtained from conventional lipoplasty, albeit not as ideal as fresh specimens. An in vivo study will be conducted to confirm the results from our present in vitro study.