Abstract
BACKGROUND: Adipose tissue contains variable amounts of stem cells that have recently attracted increased interest due to their strong proliferative and differentiation capacity. However, significant heterogeneity exists in terms of stem cell yield and viability profile among individuals as well as different donor areas. MATERIALS AND METHODS: Between June 2016 and July 2016, forty (40) women underwent outpatient cosmetic liposuction procedures conferring a total of 53 lipoaspirates; inner thigh (n=13), outer thigh (n=9), abdomen (n=9), waist (n=16) and inner knee (n=6). Lipoaspirates were harvested using a tulip low-pressure syringe lipoaspiration system with a diameter of 3 mm. Centrifugation separated adipocytes from the stromal vascular fraction (SVF). Isolation of the adipose-derived stem cells (ASCs) was achieved through culture of the SVF. Viability of SVF cells and ASCs was evaluated with trypan blue dye under microscope and using flow cytometry with 7-AAD staining, respectively. Total cell count was estimated for both the SVF and ASCs. RESULTS: Outer thigh exhibited significantly higher SVF cell count compared to any other donor site (p<0.05). In addition, inner and outer thigh showed a significantly higher number of ASCs compared to abdominal, waist, and inner knee samples (p<0.05). Finally, viability of SVF cells (range, 94-95%) and ASCs (range, 93.12-96.14%) was excellent with no significant differences among donor areas. CONCLUSION: Tissue-harvesting area is a strong determinant of the quality of the fat grafts. Compared to abdomen, waist and inner knee, thighs seem favorable in terms of viability profile and yield of SVF cells and ASCs. Further randomized controlled trials incorporating a larger cohort of patients are warranted in order to verify our results.