The effects of autologous platelet gel on inflammatory cytokine response in human peripheral blood mononuclear cells

The potential therapeutic value and versatility of platelet-derived products has recently stimulated the research and interest in the field of regenerative medicine. Platelet gels (PG), generated by thrombin-activated platelets, represent a new biotechnology for stimulation and acceleration of tissue healing and regeneration. However, despite the diffused and successful use of PG in clinical practice, a more detailed knowledge of the cellular and molecular mechanisms involved is required. In the present study, we show that human peripheral blood mononuclear cells (PBMC) co-cultured with PG, in the presence of the inflammatory activator lipopolysaccharide, secreted higher amounts of pro-inflammatory and pro-angiogenic cytokines, such as interleukin (IL)-1 beta, IL-6 and IL-8. In contrast, the release of the anti-angiogenic cytokines interferon-gamma and IL-12 was significantly reduced. In addition the production of the anti-inflammatory cytokine IL-10 was not affected by PG. Finally, hypoxia, a common feature of the healing tissue, potentiated the effects exerted by PG on the release of IL-1 beta by PBMC. In conclusion, PG treatment reveals a unique capacity of articulating a pro-inflammatory and pro-angiogenic cytokine profile in human PBMC, which may partially explain the clinical success of PG application in a wide range of diseases.