PB0155 - A potential use of leukocyte-platelet rich fibrin secretome to improve wound healing and bone regeneration

Background: Leukocyte-platelet rich fibrin (L-PRF) is a bioproduct with platelets, leukocytes and a high-density fibrin network. This biomaterial is very popular in dentistry for the treatment of oral wounds because of the growth factors released by platelets after activation. Recently, our group has characterized the whole secretome released by L-PRF at different time points, finding changes over time that would benefit tissue regeneration (Hermida-Nogueira et al. Sci Rep. 2020).

Aims: Therefore, our aim was to evaluate the effect of L-PRF secretomes, collected at different time points, on several cell types related to the wound healing process.

Methods: The effect of the secretome was analysed on fibroblast proliferation and migration. Furthermore, the osteogenic potential of the secretome was evaluated in mesenchymal stem cells (MSC) measuring different bone formation biomarkers and cytokines.

Results: L-PRF secretome collected at different time points showed differential effects on fibroblast migration and proliferation depending on the concentration applied. Low concentrations of secretomes collected at day 3 increased fibroblast proliferation and migration, however higher concentrations inhibited both processes. On the contrary, high concentrations of secretomes collected at day 7 showed a significant increase on fibroblast migration. Regarding the osteogenic potential, the levels of bone biomarkers OPG, DKK-1 and calcium deposits were significant raised in MSC treated with L-PRF secretomes. However, VEGF and MCP-1 levels were also increased.

Conclusion(s): Differential effects on fibroblast migration and proliferation were found when the L-PRF secretome collected at specific time points was applied at different concentrations. This result suggests a specific secretome protein contribution to wound healing. The L-PRF secretome had also an effect on osteogenic differentiation of MSC, as well as a primary or secondary effect on other cell types such as endothelial cells, increasing the potential use of L-PRF in other clinical scenarios.

Funding: Intra-Lock Iberia and Xunta de Galicia (predoctoral grant 2018)