Bioactivity and stability of endogenous fibrogenic factors in platelet‐rich fibrin

TLDR

Platelet‑rich fibrin (PRF®) is an autologous fibrin sealant enriched with over a million platelets per microliter, produced by the Vivostat® system, and is used to accelerate wound healing. The study compared PRF’s effects with thrombin‑activated platelet concentrate, recombinant PDGF isoforms, and a homologous fibrin sealant in cultured normal human dermal fibroblasts, and examined the release and proteolytic stability of endogenous growth factors from PRF. PRF induced greater fibroblast proliferation than the fibrin sealant and rhPDGF‑BB, promoted collagen propeptide secretion, resisted proteolytic degradation of PDGF‑AB and TGF‑β1, and its mitogenic effect was not blocked by anti‑PDGF antibody, demonstrating sustained release and protection of fibrogenic factors for wound healing.

Abstract

ABSTRACT Platelet‐rich fibrin (PRF ® ) is an autologous fibrin sealant (FS) enriched with a platelet concentrate (>1,000,000 platelets/μL) produced by the automated Vivostat ® system and used to enhance wound healing. The effects of PRF were compared with supernatant from thrombin‐activated platelet concentrate, recombinant human platelet‐derived growth factor (rhPDGF) isoforms, and a homologous FS in cultured normal human dermal fibroblasts. Also, the release of selected endogenous growth factors from PRF and their stability against proteolytic degradation were studied. The proliferative effect of PRF exceeded that of FS and rhPDGF‐BB, although it was lower than thrombin‐activated platelet concentrate possibly due to sustained growth factor release from platelets in PRF. Anti‐PDGF antibody blocked the mitogenic effect of rhPDGF‐BB but not that of PRF in growth‐arrested fibroblasts. PRF promoted secretion of carboxyterminal propeptide of type I collagen into conditioned medium while rhPDGF‐AB had no significant effect on collagen biosynthesis. Limited proteolysis of PDGF‐AB and no proteolysis of transforming growth factor‐β1 (TGF‐β1) in PRF were observed with trypsin treatment, whereas rhPDGF‐AB and rhTGF‐β1 in bovine serum albumin, matching the total protein concentration of PRF, were almost completely degraded after 24 hours at 37 °C. To conclude, PRF provides sustained release and protection against proteolytic degradation of endogenous fibrogenic factors important for wound healing.