White cell and platelet content affects the release of bioactive factors in different blood-derived scaffolds

Abstract

Platelet-derived factors are biomaterials that might accelerate healing process in oral, maxillofacial, and several other applications. Release of specific factors by platelet concentrates is critical to achieving a successful outcome. Here, we have shown that platelet-rich fibrin (PRF) clots were beneficial sources of leukocytes, which may directly affect the release of chemokines and growth factors. When compared with the standard leukocyte-PRF (L-PRF), the experimental low-force modified procedure [defined as advanced-PRF (A-PRF)] entrapped the same content of viable leukocytes, released a similar amount of inflammatory cytokines, but secreted 3-, 1.6-, 3-, and 1.2-fold higher levels of Eotaxin, CCL5, platelet-derived growth factor (PDGF) and vascular endothelial growth factor (VEGF), respectively. A leukocyte-free scaffold, such as plasma rich in growth factors (PRGF), released only platelet-specific factors and, in particular, the F3 fraction, the richest in growth factors, secreted higher amount of CCL5 and PDGF compared to F1 and F2 fractions. In conclusion, different procedures and leukocyte content affect cytokine, chemokines, and growth factor release from platelet derivatives, which may be helpful in different clinical settings.

Platelet‐rich plasma counteracts detrimental effect of high‐glucose concentrations on mesenchymal stem cells from Bichat fat pad

“…Platelet products are widely used in all medical fields that require tissue regeneration due to the positive effects in acceleration and promotion of wound healing, reduction of bleeding, and regeneration of soft and hard tissues (Burnouf et al, 2013; Cabaro et al, 2018). During normal tissue repair, platelets release high concentrations of proteins involved in cell proliferation, chemotaxis, and extracellular matrix production/angiogenesis, such as platelet‐derived growth factor (PDGF), transforming growth factor β (TGF‐β), and vascular endothelial growth factor (VEGF).…”

Effects of L‐PRF and A‐PRF+ on periodontal fibroblasts in in vitro wound healing experiments

“…The same group found also increased fibroblasts migration and proliferation in cultures with A‐PRF + conditioned medium . Cabaro et al reported that L‐PRF and A‐PRF + contained similar numbers of viable leukocytes and released a comparable quantity of inflammatory cytokines, but A‐PRF + stimulated cultures secreted 3‐, 1.6‐, 3‐, and 1.2‐ fold higher levels of eotaxins, CCL5, platelet‐derived growth factor (PDGF), and vascular endothelial growth factor (VEGF), respectively. Eotaxins and CCL5 are pro‐inflammatory chemokines chemotactic for T cells and leukocytes, and they are overexpressed during the early phase of tissue injury.…”

“…The same group found also increased fibroblasts migration and proliferation in cultures with A-PRF + conditioned medium. 20,28 Cabaro et al 23 A shortcoming of our study is that we did not use the real fibrin matrix to induce migration, but only conditioned medium containing a mixture of growth factors, chemokines, and cytokines that were released from the clot. We used this design because some cross reaction between leukocytes from patients and cells from stocks from different donors were possible, which could influence the results.…”

“…The generated A‐PRF + fibrin matrix showed a more porous structure, allowing more space for trapped platelets and immune cells and therefore a higher and more sustained release of growth factors, compared with L‐PRF . In contrast, other recent investigations showed different results, reporting better histological and mechanical characteristics in favor of L‐PRF . It is still unclear whether the morphological differences that may affect the difference in growth factor release from generated PRF membranes will have a real impact on the fibroblast cells involved in the periodontal reparative and regenerative processes during wound healing.…”

“…[19][20][21][22] In contrast, other recent investigations showed different results, reporting better histological and mechanical characteristics in favor of L-PRF. 23 It is still unclear whether the morphological differences that may affect the difference in growth factor release from generated PRF membranes will have a real impact on the fibroblast cells involved in the periodontal reparative and regenerative processes during wound healing. Therefore, the aim of the present study was to compare the effects of released factors by A-PRF + and L-PRF membranes on in vitro proliferation and migration of gingival and periodontal ligament fibroblast cells.…”