Studies On Enhancing The Effects Of Autologous Fat Transfer

[OBJECTIVES]1. Comparing the effects of different sources of fat tissue in autologous fat transfer.2. Comparing the effects of different purification methods, such as standing or different centrifugal forces, on volume maintenance and qualities of transferred fat.3. Studies on the effects of the adipose-derived stem cells in enhancing the efficiency of fat transfer.4. Studies on the effects of the platelet-rich plasma in the results of fat transfer.[MATERIALS and METHODS]Part1, Study on the different impact factors to traits of harvested adipose tissue. To analyze the apparent traits of adipose tissue, which harvested from different sites, purified by different methods and treated by different influence factors, by measuring the changes of volume and mass of transferred adipose tissue and the cell activity indicated by glucose transfer method. The experimental groups were divided into the inner thigh group, the lateral thigh group and the abdominal group according to different sources. The abdominal group was then divided into into4groups, the standing group, the low-speed centrifugation (40g) group, the medium-speed centrifugation (100g) group and the high speed centrifugation (1000g) group according to different purification methods. Meanwhile, the abdominal group was divided into another3groups, the control group (without any treatment), the adipose stem cell(ASCs) group and the platelet-rich plasma (PRP) group according to different influence factors.Part2, Study on the different impact factors to the effect of fat transfer in nude mice. The size of the specimens were measured and fitted the correlation function by the software MATLAB7.0. The size of each specimen was follow-uped once a week within six weeks after transplantation, The apparent parameters, including liquefied phenomenon,were detected by the small animal ultrasound in nude mice before euthanasia. The volume and mass of the specimens were measured after euthanasia. The consistency between surface measurement and ultrasound measurement was analyzed. Histological analysis were applied to observe the effects of fat transfer by using aspirated adipose tissue from different donor sites, purification methods, and different influence factors.[RESULTS]Part1,1. The density of adipose tissue from different donor sites has no statistical significance (p>0.05).2. The ratio between the volume after centrifugation and the original volume which measured after standing15minutes showed that the low-speed centrifugation group is85%, the medium-speed centrifugation group is81%and the high speed centrifugatigroup is75%. It suggested there were statistically significant differences on the liquid content of the fat graft among the centrifugation groups and the standing group (p<0.05).3. Consuming the cell activity, the amount of consumed glucose in one hour showed that the standing group is7.43±2.74mmol/1, the40g group is4.03±1.43mmol/1, the100g group is3.75±1.8mmol/1and the1000g group is3.66±2.26mmol/1. There were statistically significant differences among the standing group and the centrifugation groups (P<0.05). Nevertheless, there was no significant difference between the refrigerated fat tissue in adipose stem cell(ASCs) group and in standing group.Part2,1. There was no statistical significance between different sources of fat tissue on volume changes in nude mice6weeks after transplantation (P>0.05).2. The terminal volume of adipose grafts by using different purification methods shows that the standing group is65.9±23.1mm3, the40g group is60.8±30.0mm3, the100g group is76.2±14.4mm3and the1000g group is90.7±17.1mm3. Concerning about the results of the volume ratio in the first part study, there were statistical differences among the standing group, low-speed centrifugation group, the medium-speed centrifugation group or the high speed centrifugation group (p<0.05). The results of ultrasound measurement revealed that the number and degree of liquefied cases in the standing group were better than the centrifugal groups. The results of histology anslysis showed that the obvious destruction occurred in the medium-speed and high speed centrifugation groups.3. There was no significant difference between the adipose stem cell group and the control group in the volume change of fat graft. The optimization effect of fat graft on volume maintenance by PRP treatment was statistically significantly good. Moreover, the histological analysis revealed that the neovascularized tissue formed in PRP group.[Conclusions]1. There were no differences among the fat grafts from different donor sites on the volume change and survival qualities.2. Centrifugation would cause irreversible damage to the fat grafts and lead to fat liquefaction no matter what the centrifugation speeds were. Absorption rates of high-speed centrifugal group and standing group were relatively small. However, the survival qualities of the fat grafts of the standing group was much better than the centrifugal groups.3. No optimization of the role of the volume maintenance in fat grafts by the adipose stem cells (ASCs). Its value may be found by the observations for a long time.4. The platelet-rich plasma (PRP) assisted optimized the volume maintenance in fat graft. This may be related to its effect of inducing neovascularization.