Point-of-Care Adipose-Derived Stromal Vascular Fraction Cell Isolation and Expanded Polytetrafluoroethylene Graft...

Adipose-derived stromal vascular fraction (SVF) cell populations are being evaluated for numerous clinical applications. The current study evaluated a point-of-care technology, the Tissue Genesis "TGI 1000" Cell Isolation System™, to perform an automated isolation of adipose-derived SVF cells to be used in the fabrication of a tissue-engineered vascular graft in the operating room. A total of seven patients were enrolled in this study and received femoral to tibial expanded polytetrafluoroethylene bypass grafts to treat peripheral arterial disease. Lipoaspiration of fat was performed on five patients, and the fat sample was processed immediately in the automated system in the operating room. The mean processing time, from the point of fat delivery into the instrument to removal of the SVF-containing syringe, was 70 min. The SVF cell population was evaluated for cell yield, cell viability, endotoxin levels, and microbial contamination. Samples of the SVF preparation were further subjected to microbiologic evaluation both microscopically before implantation of the graft and through a microbiologic screening using aerobic and anaerobic culture conditions. Mean cell yield was 1E5 cells per cc of fat, and endotoxin levels were below the FDA recognized standards. All SVF preparations were released for graft preparation, and the intimal surface of 90-cm-long grafts was pressure sodded with cells at a concentration of 2E5 cells/cm². The sodded grafts (n = 5) and control grafts (n = 2) were immediately implanted and graft patency assessed for 1 year. One year patency was 60% for sodded grafts and 50% for control grafts. Automated preparation of autologous adipose-derived SVF cells for immediate use to create cellular linings on vascular grafts is feasible and safe.