The Improving Effect Of Autologous Stromal Vascular Fraction (SVF) In Adipose Tissue On Skin Grafting

Background:In plastic and reconstructive surgery,skin grafting is still widely used as a basic method to cover skin defect.Skin grafting stands out for its easy operation process and high success rate,and leave less damage to the donor site,but the grafted skin tend to have pigmentation and rigid texture,sometimes the grafted skin may contracture too much that the patient have to have a second operation to correct the malfunction of the recipient sites.With all these shortages,the skin grafting may not be the first choice of recovering the defects for cosmetic reasons or those near the joints and require the restoring of maximum function with minimum contracture.Studies show that,the bad outcome of skin grafting is related to the lack of dermal collagen and adipose tissue.If there is a way that could increase dermal collagen density while forming a thin layer of adipose tissue under the grafts,better outcome may be achieved.The stromal vascular fraction(SVF)cells are a variable cell population that includes adipose-derived stem cells(ASCs),and have been widely studied in areas like angiogenesis,skin regeneration etc.and many good results are observed.Objective:To explore the improving effect of autologous stromal vascular fraction(SVF)in adipose tissue on skin grafting,to observe the results of improvement on skin color,skin texture,skin contracture rate as well as the safety of SVF on skin grafting.Methods:(1)We enrolled 18 patients according to our enrollment standard,all patients signed the informed consent form before the surgery;(2)The adipose tissue was harvested by liposuction during the operation of skin grafting,then digested and processed;(3)SVF(1×10~5/cm~2)was injected onto the wound surface or under the grafted skin of the treatment group just before the closure of the skin grafts,while the control group was treated with saline;(3)The skin grafts texture and contracture were tested and measured at 1 month,3 months,6months and 12 months after the surgery;(5)During the therapy and follow-ups,the safety of SVF was also measured.Results:(1)After the dressings were removed,no skin grafts necrosis observed in both control group and treatment group.(2)During the follow-ups,compare to the control group,the skin color(water content)ratio=grafted skin color(water content)/donor site skin color(water content),the treatment groups tend to have skin color that was more similar to the donor site at 6months(Treated:1.25±0.004,control:1.6±0.1,p<0.05)and at 12 months(Treated:1.12±0.1,control:1.5±0.1,p<0.05);the treated group tend to have a better skin water content at 3months(Treated:2.2±0.14,control:1.6±0.125,p<0.05)and 6 months(Treated:1.12±0.02,control:0.4±0.125,p<0.05);compare to the control group,the elasticity of the treated group grafted skin greatly improved at 3 months,6 months and 12 months(p<0.05);(3)The contracture rate of the treatment groups were lower than the control groups at time points of 1 month(Treated:2±1.0%,control:12±1.6%,p<0.05)and 3 months(Treated:12.5±3.3%,control:25±5.0%,p<0.05).Conclusion:These results suggest that the transplantation of SVF is a safe treatment that can improve the effect of skin grafting by improving skin color and texture,while reducing grafted skin contracture.