Stromal vascular fraction (SVF) cells are endothelial and mesenchymal progenitor cells derived from human adipose tissue.
Adipose tissue, isolated by liposuction or excision, was finely minced. Samples were digested with collagenase type II (355 U/mg) for 60–90 min at 37 °C. After centrifugation at 190 g for 10 min, the lipid-rich layer was discarded and the cellular pellet was washed once with phosphate buffered saline (PBS). Red blood cells were lysed by incubation for 2 min, in a solution of ammonium chloride (0.15 m), potassium hydrogen carbonate (1 mm) and EDTA (0.1 mm). The resulting SVF cells were then resuspended in complete medium (CM), consisting of α-MEM supplemented with fetal bovine serum (10%), HEPES (1%), sodium pyruvate (1%) and penicillin-streptomycin-glutamin solution (1%).
For monolayer expansion, SVF cells were seeded at a density of 2 × 103 cells/cm2 onto tissue culture plates, cultured in CM supplemented with FGF-2 (5 ng/mL). Cells were serially replated onto new dishes at a density of 3 × 103 cells/cm2 when reaching subconfluence.