Background: Supplementation of fat grafts with stromal vascular fraction cells is an emerging technique used to improve graft reliability. A variety of systems for isolating stromal vascular fraction cells are commercially available. The lack of performance data obtained operating the systems in a standardized environment prevents objective assessment of performance. This prospective, blinded study compared performance of four commercially available stromal vascular fraction isolation systems when operated in a clinical outpatient surgery environment.
Methods: Four different systems were compared: (1) PNC's Multi Station, (2) CHA Biotech Cha-Station, (3) Cytori Celution 800/CRS System, and (4) Medi-Khan's Lipokit with MaxStem. Identical lipoaspirate samples from five separate volunteer donors were used to evaluate system process time, viable cell yield, composition, residual enzyme, and operating costs.
Results: The mean processing time ranged from 88 to 115 minutes. The highest mean number of viable nucleated cells was obtained using the Celution System (2.41 × 10 cells/g) followed by the Multi Station (1.07 × 10 cells/g). Lipokit and Cha-Station systems yielded nearly a log fewer nucleated cells (0.35 × 10 cells/g and 0.05 × 10 cells/g, respectively). The Celution System also yielded significantly more endothelial cells, CD34/CD31 cells, and adipose-derived stem cells (colony-forming unit-fibroblast). Residual enzyme levels observed with the Multi Station, Cha-Station, and Lipokit, respectively, averaged 5.1-, 13.0-, and 57-fold higher than that observed with the Celution System.
Conclusions: Although all systems generated measurable amounts of stromal vascular fraction, significant variability exists in the number, identity, and safety profiles of recovered viable cells. Side-by-side clinical trials will be required to establish the relevance of these differences.