Phenotypic and Cellular Characteristics of a Stromal Vascular Fraction/Extracellular Matrix Gel Prepared Using Mechanical Shear Force on Human Fat

Abstract

The retention of fat-derived grafts remains a challenge for regenerative medicine. Fat aspirates from patients undergoing liposuction were prepared into standard Coleman fat grafts or further isolated using mechanical shear force to prepare a stromal vascular fraction (SVF)/extracellular matrix (ECM) gel. The retention rate of the SVF/ECM gel was significantly higher than that of the Coleman fat at 3, 14, 28, and 60 days following transplantation on the backs of nude mice. The viscosity of the fat was directly proportional to the shearing force. Although the mechanical isolation did not affect the total number of cells, it significantly decreased the number of living cells. Flow cytometry showed a greater number of mesenchymal stem cells, supra-adventitial (SA)-adipose stromal cells (ASCs), and adipose-derived stem cells but a lower number of endothelial progenitor cells in the SVF/ECM gel than in the Coleman fat. Thus, mechanical isolation of fat can increase the pluripotency of adipocytes, which can improve graft retention in cell therapy.

Advanced methods to mechanically isolate stromal vascular fraction: A concise review

“…Emulsification did not affect the total number of cells, but significantly decreased the number of living cells. [ 28 ] Banyard et al. 2016 Emulsification did not affect the cell number; however, viability was greatly reduced compared with the stromal vascular fraction of standard lipoaspirate.…”

One-step stromal vascular fraction therapy in osteoarthritis with tropoelastin-enhanced autologous stromal vascular fraction gel

“…The key constituents are MSCs, renowned for their regenerative capabilities ( Cai Y. et al, 2023 ). Additionally, SVF-gel retains extracellular matrix (ECM) proteins, providing a natural scaffold that fosters cell adhesion, survival, and differentiation ( Ye et al, 2021 ). In the field of plastic surgery, SVF-gel has been effectively utilized to enhance tissue volume, promote hair growth, improve skin texture, and promote wound healing ( Wang et al, 2019 ; Xiao et al, 2020 ; Cai J. et al, 2023 ).…”

Comparison of stromal vascular fraction cell composition between Coleman fat and extracellular matrix/stromal vascular fraction gel

“…The ECM niche of ECM/SVF-gels provides a beneficial scaffold for SVF cells to survive and exert their biological function. Flow cytometry shows that condensed ECM/SVF-gels contain higher SVF cell density, as compared with Coleman fat, despite that the total live cell number of SVF cells decreases due to cell death and loss during mechanical processing of the ECM/SVF-gel [ 6 , 17 ]. Previous studies [ 6 , 17 ] usually used flow cytometry, only according to cellular surface marker expression, to compare the SVF cell content between the two groups, and mainly focused on ADSCs, endothelial cells, pericytes, and CD45+ haematopoietic cells, and also did not further identify immune cell subsets.…”