Adipose-derived Stromal Vascular Fraction(SVF) Therapy For Refractory Wounds

Background and purpose:Refractory wounds are common diseases of surgery, and has the characteristics of long duration, large effect on appearance, and many complications. There is an increasing trend in recent years, becoming an important impact on the life quality of patients. Surgeons have been exploring how to promote refractory wound healing, but so far no ideal method.In recent literature, one potential strategy in tissue regeneration is the transplant of mesenchymal stem cells (MSCs), which were first described as immature cells in adult bone marrow. MSCs are capable of differentiating into different types of stem or progenitor cells, which have been shown to accelerate wound healings by improving vascularization and tissue regeneration. However, MSCs derived from bone marrow are limited to the small number of stem cells and a painful process. MSCs can also be obtained in adipose tissue which is relatively easy to obtain in large quantities, higher content of MSCs, and excellent expansion and proliferation capacities as compared with bone marrow.The adipose-derived stromal vascular fraction (SVF) is isolated from adipose tissue through the process of digestion and centrifugation, including a heterogeneous cell population, which was first described by Zuk et al.. The SVF was consisted of mesenchymal stem cells, endothelial progenitor cells, smooth muscle cells, monocytes/macrophages and pericytes, as well as differentiated toward the adipogenic, osteogenic, chondrogenic, and myogenic lineages in the presence of established lineage-specific differentiation factors. The improved effect of wound healing has been considered to be achieved by differentiating into vascular cells and secreting angiogenic factors, antiapoptotic factors and cytokines.Although, some clinical case reports have focused on adipose-derived SVF in the treatment of refractory wounds, which have displayed a certain clinical effect, all of these are some exploratory research. This study further evaluated the effects related to the application of SVF on refractory wounds caused by a variety of reasons.Patients and methods1. PatientsAccording to the screening criteria for patients, a total of12patients were treated using SVF for refractory wounds. Control treatment was performed on20patients.2. Operation procedureThe treatment of svf for trial group:2.1Abdominal liposuction:patients’adipose tissue was obtained from liposuction procedures under local anesthesia.2.2Isolation stromal vascular fraction from adipose tissue:the SVF suspension was obtained through the process of digestion and centrifugation.2.3Cell transplation:After collecting preoperative photographs and debride-ment operation, the cell suspension of SVF was injected into the perilesional and the bed of wounds.2.4Dressing change:the dressing was changed at2to3-day intervals after operation. Postoperative photographs of wound were collected, taking into account the same size, brightness and position.2.5Follow-up:the patients were weekly followed up for eight weeks after surgery.In the control group, the patients were treated with conventional therapy, taken photographs of wound and followed up for eight weeks.3. Evaluation for wound healingBy analysis of preoperative and postoperative photographs, the authors evaluated the wound healing time, percentage of wound shrinkage, and efficiency of wound healing in four weeks and eight weeks after treatment, respectively. Results1. Wound healing time and percentage of wound shrinkageThe wound healing time (mean,39.54±18.84days) in the SVF-treated group significantly shortened compared with the time (mean,62.40±23.98days) in the control group(P<0.05).The percentage of wound shrinkage (mean,86.92±19.95%) and (mean,99.08±2.78%) were observed in the SVF-treated group after four weeks and eight weeks, respectively, and the percentage (mean,55.50±25.86%) and (mean,87.75±15.68%) in control group(P<0.05).2. Efficiency of wound healingAfter4weeks, the wound treatment efficiency (92.30%) in the SVF-treated group significantly improved compared with the efficiency (50.00%) in the control group.After8weeks, the wound treatment efficiency in the experiment group and the control group were100%3. No adverse event occurred in any process of treatment.ConclusionsCompared with the traditional treatment methods, the application of SVF showed an evident improvement in the healing of refractory wounds. The therapy using SVF may be a promising therapy for improving wound healing.