Searching for the Ideal Method for Optimal Cryopreservation of Human Fat Grafts

Autologous fat transplantation (AFT) is a common cosmetic and reconstructive procedure performed by plastic surgeons to correct various soft tissue deficiencies of congenital, posttraumatic, or iatrogenic defects and to rejuvenate faces. hands, or other parts of the body secondary to aging. AFT has also been used extensively to correct irregularities caused by liposuction for aesthetic improvement of body contour. However, the main obstacle to achieve long-term favorable results of soft tissue augmentation after AFT is the high rate of absorption in the grafted site, reaching up to 70% of the filled volume. The high rate of absorption after AFT often necessitates either overcorrection or repeated procedures in the desired area, causing patient's discomfort, less than optimal appearance, dissatisfaction, increased cost, and morbidity or trauma of the donor site. Liposuction is the most common cosmetic procedure in the United States and its popularity is increasing. However, adipose aspirates can only be used for immediate autologous fat grafting during the same setting of liposuction and at the present time, adipose aspirates obtained from the procedure are usuall y discarded. It has been a strong desire of both plastic surgeons and patients to preserve the adipose aspirates for potential future applications. To the best of our knowledge, there are no reliable and clinically feasible methods for the longterm preservation of adipose tissues for possible future repeated transplantations. It is our hypothesis that adipose aspirates obtained from routine cosmetic liposuction could be successfully preserved and stored by means of an optimal but practical cryopreservation technique for possible future repeated autologous fat transplantations. The overall objective of this research project is to perform an in vitro study to determine the best concentration of trehalose, used as a non-permeable cryoprotective agent, within our optimal cryopreservation protocol recently developed and subsequently to conduct an in vivo study to confirm our refined optimal cryopreservation protocol for cryopreservation of adipose tissues. The speci fic aims of the present study are (l) to identify a reliable and practical long-term preservation protocol for adipose tissues in an in vitro study; (2) to confirm the results from our in vitro study in an in vivo animal study in preparation for future clinical study of autologous fat transplantations; and (3) to improve our understanding of the fundamental cryobiology of adipose tissues.