Leukocyte-reduced platelet-rich plasma stimulates the in vitro proliferation of adipose-tissue derived mesenchymal stem cells depending on PDGF signaling

BACKGROUND: Platelet-rich Plasma (PRP) is suggested as xenoprotein-free cell-culture medium replacement for animal-derived supplements. OBJECTIVE: The aim of this study was to investigate PRP-triggered signaling in adipose derived mesenchymal stem cells (ASCs). METHODS: PRP was obtained from 4 male patients. We incubated ASCs in alpha-MEM with different Platelet derived growth factor (PDGF) subtypes or 10% or 20% pooled PRP or 20% fetal calf serum (FCS) prior to determination of the S-phase fraction (SPF). To investigate the influence of PDGF signaling on ASCs, PDGF receptor beta inhibitor was added, and protein expression of ASCs was measured. RESULTS: ASCs exposed to 20% PRP, PDGF-AB and -BB demonstrated significant higher SPF in comparison to PDGF-AA and 20% FCS after 48 hours (all P < 0.05). PDGF receptor beta inhibition diminished the PRP-induced SPF increase of ASCs significantly after 48 hours (P < 0.01). ASCs with PDGF receptor beta inhibition showed significant higher PDGF receptor beta and significant lower c-MYC expression compared to untreated cells in presence of 20% PRP after 48 hours (both P < 0.05). CONCLUSIONS: The proliferation promoting effect of PRP on ASCs is mediated by PDGF signaling and is associated with c-MYC overexpression.