Growth factors and cytokines in autologous platelet concentrate and their correlation to periodontal regeneration outcomes

Aim: To determine the concentration of naturally available biologic mediators in autologous platelet concentrates and their correlation with periodontal regeneration outcomes. Material and methods: In 25 patients with two intra-bony defects each, an autologous platelet concentrate (APC) was prepared by a laboratory thrombocyte apheresis technique pre-operatively. Both defects were treated using a bioresorbable guided tissue regeneration-membrane in combination with tricalciumphosphate (TCP). In the test defect, APC was additionally applied. In the APC, platelets were counted and the levels of growth factors and cytokines were determined by ELISA. Correlations between the platelet counts or the growth factor/cytokine levels and the potential clinical and radiographic regeneration outcomes due to APC were calculated after 3, 6, and 12 months. Results: The APC contained 2.2 x 10(6) platelets/mu l, which was 7.9 times more than in the venous blood. Transforming growth factor-beta 1 (TGF-beta 1), insulin-like growth factor-I (IGF-I), platelet-derived growth factor-AB (PDGF-AB), PDGF-BB, vascular endothelial growth factor (VEGF), and epidermal growth factor (EGF) were found in the APC, whereas interleukin-1 beta (IL-1 beta), IL-6, tumor necrosis factor alpha (TNF alpha), IL-4, and IL-10 were not detectable. The regression analysis showed a weak correlation between the platelet counts or the growth factor levels and the clinical and radiographic regeneration outcomes (r(2) <= 0.4). Conclusion: Autologous platelet concentrate contains relatively high concentrations of PDGF-AB, PDGF-BB, TGF-beta 1, and IGF-I, but their potential influence on periodontal regeneration remains unclear.