Effect of the Bowl Structure in an Automated Cell-Isolation Device on Stromal Vascular Fraction's Isolation Yield

Abstract

The enzymatic digestion of lipoaspirate is used to isolate the heterogeneous stromal vascular fraction (SVF) that contains the adipose-derived stromal cells (ASCs). Several automated SVF isolation systems are used to operate standard technical procedures and avoid human errors. However, the yield of isolated cells and the residual collagenase activities of the SVF samples obtained from automated systems are not satisfactory compared to those from manual isolation methods. In this study, we evaluated the efficiency and the reliability of a new automated SVF isolation system in which the bowl was designed in the shape of a radial protrusion at each angle (a top-type bowl). The viability and yield of cells and the residual collagenase activities of SVFs obtained in a top-type bowl were compared with the SVFs obtained in a conventional bowl. We achieved a significantly higher yield of cells and decreased residual collagenase activity in the SVFs obtained from a top-type bowl (18.0 × 105 cells/mL of fat) compared to a conventional bowl (2.3 × 105 cells/mL). There was no significant difference in the cell viability between the two groups. These results suggest that the automated SVF isolation system with an improved bowl structure will potentially yield higher numbers of nucleated cells and decreased residual collagenase activity compared to conventional automated systems in cell-based clinical trials.