The mechanism of the antibacterial effect of PCs is not yet fully understood. Existing evidence suggests that platelets may play multiple roles in antimicrobial host defense: they generate oxygen metabolites, including superoxide, hydrogen peroxide and hydroxyl free radicals; [13–15] they are capable of binding, aggregating, and internalizing microorganisms, which enhances the clearance of pathogens from the bloodstream; they participate in antibody-dependent cell cytotoxicity functions to kill protozoal pathogens; finally, platelets release an array of potent antimicrobial

peptides [16, 17]. Several techniques are available for the production of PCs, leading to products with different biological characteristics. The various PCs can be classified BAY 73-4506 cell line into four

main categories, depending on their leucocyte and fibrin content: pure platelet-rich plasma (P-PRP), pure platelet-rich fibrin (P-PRF), leukocyte- and platelet-rich plasma (L-PRP) and leukocyte- and platelet-rich fibrin (L-PRF). [18] L-PRP and L-PRF might contain substantial amount of white blood cells. The respective effects of platelets and leucocytes in PCs have not been elucidated yet, and the contribution of leucocytes to the observed overall effect remains unclear [19]. Therefore in this study we decided to use a widely documented technology developed in 1999 by Anitua that allows the production Ibrutinib purchase of leukocyte-poor platelet concentrate [20]. The aim of this study

was to evaluate in vitro the antibacterial effect of P-PRP against microorganisms colonizing the oral cavity such as Enterococcus faecalis, Candida albicans, Streptococcus agalactiae, Streptococcus oralis and Pseudomonas aeruginosa. Methods Donors Blood samples were obtained from 17 adult patients (two men, 15 women; mean age 59 ± 11 years, age range 34–75 years) who underwent Bcl-w oral surgery procedures (dental implant placement, tooth extraction) involving the use of P-PRP. All subjects were in general good health (ASA 1–2). No patient took antibiotics during the month before surgery, nor was under anticoagulant or immunosuppressive therapy. Written informed consent for participation in the study was obtained from all patients. The present research was performed within the guidelines of the Helsinki Declaration for biomedical research involving human subjects. The study was approved by the Review Board of the Galeazzi Orthopedic Institute. Blood collection and production of P-PRP Fresh human whole blood from donors was processed using PRGF® System IV (BTI, Biotechnology Institute, Vitoria, Alava, Spain) to create a platelet concentrate, according to manufacturer’s protocol.