The angiogenic potential of leukocyte- and platelet-rich fibrin

Abstract

Introduction: L-PRF promotes tissue healing in clinical applications such as dental surgery. However, little is known about the mechanisms of action. Angiogenesis is a key process in tissue regeneration. Growth factors, fibrin and leukocytes, as present in L-PRF, are known to be important in angiogenesis. The goal of this study was to investigate whether L-PRF induces blood vessel formation. Materials and methods: The angiogenic cytokine profile of L-PRF CM and exudate was determined by an antibody array. The effect of L-PRF, and the involvement of CXCR2, on HUVEC viability, migration and tube formation was examined in vitro. Surface expression of CXCR2 on HUVEC was verified by flow cytometry. The ability of L-PRF to induce blood vessel formation in ovo was assessed. Results: An upregulation of pro-angiogenic factors that bind to CXCR2 was observed in CM. L-PRF was able to enhance in vitro HUVEC viability, migration and tube formation, although the CXCR2 antagonist SB225002 did not attenuate these effects. Flow cytometry showed that a small percentage of HUVEC expresses CXCR2. The pro-angiogenic effect of L-PRF was confirmed in the CAM assay. Conclusion: L-PRF exerts pro-angiogenic effects in vitro and in ovo. CXCR2 was not found as a main mediator of this enhancement. A better insight in the mechanisms of action of L-PRF is required to better understand its clinical effects and its potential as a strategy for therapeutic angiogenesis.