Studies on the Proper Storage Period and Change of -20 degrees C Cryopreserved Adipocyte

ABSTRACT

The use of autologous fat grafts has questionable clinical value due to unreliable grafts survival. For the purpose of improved graft survival, re-implantation of cryopreserved adipocytes is developed. The purpose of study is to analyze the changes of freeze-preserved adipocytes and to find out efficient long-term storage period. After centrifugation of aspirated abdominal tissues, 10ml of packed adipocytes were freezed at -20 degrees C (n=70). For 6 months, each 10 frozen samples were taken and analyzed at 1 month interval. Significant volume changes were observed in cryopreservation for 3 months (p < 0.05). The profiles of total lipid and FFA were not changed and no significant difference in saturated fatty acid ratio with gas chromatography. No histologic changes were observed, independent of the freezing period with H & E stain. The reduction of mitochondrial enzymatic activity was observed independent of time interval but activity of mitochondrial dehydrogenase was reduced less than 50% in XTT assay. On the basis of these data, -20 degrees C freezing for 6 months has no adverse effect to adipocytes, but frigile adipocytes, damaged cell membrane during harvest procedure, were disrupted within 1month and the maximum volume reduction were followed less than 3 months. These results demonstrate that tissue preparation cells with no cell membrane damage have the greatest viability level and cryopreservation less than 3 months has great volume effect.