OBJECTIVETo compare the releasing of growth factors between platelet-rich fibrin (PRF) and platelet-rich plasma (PRP) as well as their effects on the proliferation and differentiation of adipose tissue-derived stem cells (ADSCs) in vitro.

METHODSBlood was taken from central artery of rabbits, acquiring PRF was acquired through one time centrifuge and PRP through two times centrifuge. Five milliliters of fresh alpha-MEM was added to PRF and PRP and incubated at 37 degrees C. The time points to collect exudates was in day 1, 7, 14, 21, 28 and the mass concentrations of transforming growth factor-beta1 (TGF-beta1) and platelet derived growth factor-AB(PDGF-AB) were quantified in PRF and PRP. Then the exudates of PRF and PRP were used to culture ADSCs and evaluate the effects of PRF and PRP on proliferation and differentiation of ADSCs.

RESULTS1) Growth factor release: In the PRF exudates at different time points, the mass concentration of TGF-beta1 was the highest at day 14 and the highest mass concentration of PDGF-AB at day 7, the mass concentration of both TGF-beta1 and PDGF-AB was the highest at the first day and then gradually declined. 2)The effect on proliferation and differentiation: PRF exudates of day 14 expressed the maximum proliferation and alkaline phosphatase (ALP) activity. PRF exudates of day 1 demonstrat the maximum proliferation and ALP activity.

CONCLUSIONComparing to PRP, PRF releases growth factors gradually and expressed stronger and more durable effect on proliferation and differentiation of ADSCs in vitro.