Development Of Human ADSC-EV Aided Fat Transplantation Technology And Its Optimism Study

Objective: To investigate the effect of adipose tissue mesenchymal stem cell-derived extracellular vesicles(ADSC-EV)on the retention volume of fat transplantation and optimize the application of ADSC-EV.Method: To test the angiogenesis ability of ADSC-EVs,they were isolated from the supernatant of cultured human ADSCs and incubated with human umbilical vein endothelial cells(HUVECs)in vitro.Then,ADSC-EVs were co-transplanted with fat into nude mice subcutaneously(EV group).Besides,ADSC-EVs were injected after 1 week after pure fat grafting(Delay-EV group).After 3 months of transplantation,retention rate and inflammatory reaction of the grafts were analyzed by histology assay.Result: ADSC-EVs could significantly promote migration and tube formation of HUVECs at the concentration of 20 ?g/m L.At 3 month after transplantation,the volume of fat grafts supplemented with delay injection of ADSC-EVs(0.11±0.02 mm3)was larger compared with EV group(0.09±0.01 mm3)and Blank group(0.06±0.01 mm3).Histological analysis demonstrated that transplants in the Delay-EV group had significantly less cysts,vacuoles,and fibrosis.Immunohistology assay further confirmed that Delay injection of ADSC-EVs could also promote vascularization and regulate inflammatory response.Conclusion: In this study,we co-transplanted ADSC-EVs with fat into nude mouse model and found that ADSC-EVs improved volume retention by enhancing vascularization and regulating the inflammatory response.Besides,delay injection of ADSC-EVs could further increase the volume retention of fat grafts.