title: Bacteriostatic effect of equine pure platelet-rich plasma and other blood products against methicillin-sensitive Staphylococcus aureus. An in vitro study.
abstract: OBJECTIVE
  1) To evaluate the bacteriostatic in vitro effect of pure platelet-rich plasma (P-PRP), pure platelet-rich gel (P-PRG), leukocyte-poor gel (LPG), platelet-poor plasma (PPP), and heat inactivated plasma (IP) against methicillin-sensitive Staphylococcus aureus (MSSA) over a period of 24 hours. 2) To determine the degradation of platelet factor-4 (PF-4), transforming growth factor beta 1 (TGF-β1), and platelet-derived growth factor isoform BB (PDGF-BB) in these equine blood components. 3) To establish correlations between platelet and leukocyte counts, PF-4 concentrations, and MSSA growth.
  
  
  METHODS
  Fourteen horses were used. Blood components were obtained by a manual protocol. Every blood component was mixed with MSSA and Müller-Hinton Broth and cultured at 37°C for 24 hours. Samples for the determination of bacterial growth (colony-forming units) and PF-4, TGF-β1 and PDGF-BB concentrations were taken at one, four, eight, 12 and 24 hours.
  
  
  RESULTS
  The bacterial growth was significantly (p = 0.01) inhibited for P-PRP, P-PRG, LPG and PPP in comparison with IP and, the positive control group during the first 12 hours. The P-PRG had higher and sustained TGF-β1 and PDGF-BB concentrations over time in comparison with the other blood components.
  
  
  CONCLUSIONS
  The plasma complement could be one of the most responsible components of the in vitro bacteriostatic effect of P-PRP, P-PRG, LPG and PPP against MSSA. Additionally, P-PRG was the better biomaterial because it had an acceptable bacteriostatic effect and the highest concentration of growth factors.
authors.forename: C
authors.initials: C
authors.lastname: López
authors.affiliation: Jorge U. Carmona, MVZ, MSc, PhD, Professor, Departamento de Salud Animal, Universidad de Caldas, Calle 65, No 26-10, Manizales, Colombia, Phone/Fax: +57 68 781516, E-mail: carmona@ucaldas.edu.co.
authors.forename: J U
authors.initials: JU
authors.lastname: Carmona
authors.forename: C E
authors.initials: CE
authors.lastname: Giraldo
authors.forename: M E
authors.initials: ME
authors.lastname: Alvarez
mesh_terms: D000818:Animals; D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D006736:Horses / Q000097:blood*; D008297:Male; D008712:Methicillin / Q000494:pharmacology*; D053657:Platelet-Rich Plasma; D013211:Staphylococcus aureus / Q000187:drug effects*
chemical_list: D000900:Anti-Bacterial Agents; D008712:Methicillin
keywords: Growth factor; leukocyte-reduced platelet concentrate; platelet factor 4; wound infection