Experimental Study On The Effect Of Different Proportions Of Frozen Storage Solution On Human Adipose Tissue

Background: Because the compatibility of autologous fat tissue,which is not of immune rejection,is better than the artificial and allogeneic tissue substitutes.The autologous fat tissue grafting,which is of relative low cost,has become an ideal soft tissue filling material,and been widely used in clinical practice.However,the high absorption and low survival rates of transplanted adipose tissue have been perplexing orthopedic surgeons.In order to achieve long-term satisfactory results,the second surgical transplants are usually needed.The scholars in the world have been trying to find a better way to improve the survival rate of transplanted fat,reduce the number of liposuction surgery: such as cryopreserving excess adipose tissue after liposuction and transplantion,rewarming and injecting it into the same patient when second transplantation needed;adding PRP,SVF and different components into the transplanted particle;selecting suitable purification methods and suction pipe diameter,negative pressure,etc.Although various studies have been ongoing,there isn't an unified and standard liposuction operation up to now.This research studied the effects of different donor sites and proportions of cryopreserved liquid composition on particle adipose activity.Objective:To explore the effects of different proportions of frozen storage solution on the activity of frozen adipose tissue from different parts,and provide a theoretical basis for the selection of proportions of frozen storage solution and donor site for the clinical adipose tissue transplant.Methods:1.The fat granules from interior and lateral thighs and abdomen of 45 conventional liposuction patients were collected.Each specimen was divided into two groups,A and B and stored respectively in a – 80Co refrigerators for 3 months.The frozen liquid composition ratioof A group is: 60% calf serum,15% two dimethyl sulfoxide(DMSO),25% glucose medium(DMEM)and B group: 30% calf serum,15% two dimethyl sulfoxide,55% glucose medium.2.The samples were recoveried after 6 months and observed in morphology with HE staining;trypan blue staining was used to calculate the death percentage of cells;mensurating cell creatine kinase to calculate fat cell failure rate;detecting the morphology and quantity of CD105 adipose derived stem cell by immunohistochemical methods.3.After rrewarming the adipose tissue from different parts and different cryopreserved solution,0.2ml granule fat tissue was transplanted to nude mice subcutaneously.The mice were sacrificed after 4 weeks,and the transplantation of adipose tissue were removed,weighed,measured in volume.HE staining was used to observe the morphology.Results:HE dyed: the full rate of fat cells from inner thigh in A group was 78.3±2.03%,while group B was 66.4±3.23%.The full rate of fat cells from lateral thigh in A group was70.5±4.53%,and the group B was 55.4±6.03%.The full rate of fat cells from abdominal in A group was 65.1±4.63%,and the group B was 51.9±5.08%.The difference between group A and B was statistically significant(P<0.05).Statistical analysis showed that compared the data from the inner thigh with another two sites,the difference was all of statistical significance in both A and B(P <0.05).Trypan blue staining showed that the rejection rate of fat cells in A group was lower than that in group B,and the rate of rejection of inner thigh fat cells was higher in the same frozen solution.The results of creatine kinase were in accordance with trypan blue.Long-term cryopreserved fat is of higher activity in freeze-stored liquid,which included 60% calf serum,15% DMSO and 25% DMEM.Among the fat tissues from outer thighs,inner thighs and abdomen,the cell activity of the inner thighs is higher,conducive to the survival of fat transplantation.Conclusion:In the A group,the fat activity of long-term storage was higher than the B group,and the fat activity of the interior thigh was higher than other parts.