Characterisation of angiogenetic growth factor production in adipose tissue-derived mesenchymal cells

Optimal vascularisation of the graft site is significant for improving the outcome of fat grafting. Adipose tissue, specifically the stromal vascular fraction (SVF), is known to regulate its own vascular network. In order to assess the production of angiogenetic growth factors, this study investigated the content of insulin growth factor (IGF), vascular endothelial growth factor (VEGF), fibroblast growth factor (FGF), platelet-derived growth factor (PDGF), leptin, and metallothioneine-9 (MMP-9) in the SVF after incubation in differentiation or proliferation media. The SVF was isolated from human subcutaneous adipose tissue. Cells were either cultured in proliferation medium (PM) or in differentiation medium (DM). The samples were analysed for the respective factors using ELISA after 3 and 6 days. The GF levels showed a distinctive characteristic over time depending on the culture medium. IGF, PDGF, and MMP-9 levels decreased with PM and increased with DM. VEGF levels were increased in both media. Leptin showed a decrease in both media. The differentiation medium was associated with high inter-individual distribution in growth factor production except for PDGF and Leptin. In conclusion, incubation with differentiation medium produces a more reliable increase of selected growth factors than incubation with proliferation medium. Enrichment of fat grafts with growth factor-activated autologous SVF samples could help to enable better ingrowth of the transplanted tissue and a more stable outcome. The scattering of the results could explain the inter-individual differences regarding the outcome.