Platelet lysate as a serum substitute for 2D static and 3D perfusion culture of stromal vascular fraction cells from human adipose tissue

Fetal bovine serum (FBS) and fibroblast growth factor (FGF)-2 are key supplements for the culture of stromal vascular fraction (SVF) cells from adipose tissue, both for typical monolayer (2D) expansion and for streamlined generation of osteogenic-vasculogenic grafts in 3D perfusion culture. The present study investigates whether factors present in human platelet lysate (PL) could substitute for FBS and FGF-2 in 2D and 3D culture models of SVF cells from human lipoaspirates. SVF cells were grown in medium supplemented with 10% FBS+FGF-2 or with 5% PL. In 2D cultures, PL initially supported SVF cell proliferation, but resulted in growth arrest shortly after the first passage. Freshly isolated SVF cells cultured with both media under perfusion for 5 days within 3D ceramic scaffolds induced bone formation after subcutaneous implantation in nude mice. However, blood vessels of donor origin were generated only using FBS+FGF-2-cultured cells. This was unexpected, because the proportion of CD34+/CD31+ endothelial lineage cells was significantly higher with PL than that of FBS+FGF-2 (33% vs. 3%, respectively). These results support the use of PL as a substitute of FBS+FGF-2 for short-term culture of human SVF cells, and indicate that more specific serum-free formulations are required to maintain a functionally vasculogenic fraction of SVF cells expanded under 3D perfusion.