Adipose-Derived Stromal Vascular Fraction Cells: Update on Clinical Utility and Efficacy.

Adipose tissue has emerged as an attractive cell source in tissue engineering and regenerative medicine because it can be easily collected and enriched with stem/progenitor cell populations. The stromal vascular fraction (SVF) derived from adipose tissue contains heterogeneous cell populations such as mesenchymal progenitor/stem cells, preadipocytes, endothelial cells, pericytes, T cells, and M2 macrophages. SVF-derived mesenchymal progenitor/stem cells can be easily expanded in vitro and have the potential to create diverse lineages of cells. Although there have been issues related to their isolation and purification, SVF cells demonstrate regenerative potential in damaged tissues or organs through paracrine and differentiation mechanisms. Furthermore, SVF cells augment immunological tolerance by promoting inhibitory macrophages and T regulatory cells and by decreasing ongoing inflammation. Numerous implantations of freshly isolated, autologous adipose tissue-derived SVF cells in cosmetic surgeries and in a wide variety of other specialties support the safety of SVF cells and have accelerated their clinical application. Despite these attractive advantages of SVF cells in clinical interventions, to our knowledge the recent status of clinical studies of various diseases has not been fully investigated. Therefore this article describes recent advances in the clinical use of SVF cells, as well as the associated challenges and future directions for this field of research. We also speculate that verification of the efficacy and safety of SVF cells requires more basic experimental research, using a standard isolation protocol, and larger randomized clinical trials of the utility of SVF cells in various diseases.