title: Preparation method and growth factor content of platelet concentrate influence the osteogenic differentiation of bone marrow stromal cells.
abstract: OBJECTIVE
  An extensive debate about the clinical benefits of autologous platelet concentrates used as a treatment option for patients with orthopedic injuries is ongoing. The aim of this study was to determine whether different compositions of platelet concentrates may affect the osteogenic differentiation of bone marrow stromal cells (BMSC).
  
  
  METHODS
  Pure platelet-rich plasma (P-PRP) and leukocyte-PRP (L-PRP) were characterized for platelet and leukocyte content. As an indicative marker of the delivery of growth factors (GFs), the release of basic fibroblast growth factor (bFGF) from platelet gel (PG) was measured at 1, 18, 48 and 72 h and at 7 d. The ability of different PGs to induce proliferation and differentiation of BMSC was evaluated by using bioactivity assays.
  
  
  RESULTS
  The platelet recovery was significantly higher in L-PRP, either fresh or frozen. PGs derived from L-PRP and P-PRP showed significant differences in terms of bFGF release and biological activity. bFGF release was faster both in fresh and frozen L-PRP preparations. Moreover, L-PRP samples were able to induce a significantly higher proliferation of BMSC compared with P-PRP or PPP samples. Even though all PG preparations allowed the deposition of mineral nodules in BMSC cultures, the mineralization activity correlated significantly with bFGF levels.
  
  
  CONCLUSIONS
  The biological activity of platelet concentrates differs according to preparation technique, which affects platelet and leukocyte content and GF availability. Because GF levels are not always optimal in subjects with defective bone healing, composition and bioactivity of PRP should be analyzed to test the reliability and potential effectiveness of the regenerative treatment.
authors.affiliation: Laboratory for Orthopaedic Pathophysiology and Regenerative Medicine, Rizzoli Orthopedic Institute, Bologna, Italy. francesca.perut@ior.it
authors.forename: Francesca
authors.initials: F
authors.lastname: Perut
authors.forename: Giuseppe
authors.initials: G
authors.lastname: Filardo
authors.forename: Erminia
authors.initials: E
authors.lastname: Mariani
authors.forename: Annarita
authors.initials: A
authors.lastname: Cenacchi
authors.forename: Loredana
authors.initials: L
authors.lastname: Pratelli
authors.forename: Valentina
authors.initials: V
authors.lastname: Devescovi
authors.forename: Elizaveta
authors.initials: E
authors.lastname: Kon
authors.forename: Maurilio
authors.initials: M
authors.lastname: Marcacci
authors.forename: Andrea
authors.initials: A
authors.lastname: Facchini
authors.forename: Nicola
authors.initials: N
authors.lastname: Baldini
authors.forename: Donatella
authors.initials: D
authors.lastname: Granchi
mesh_terms: D000328:Adult; D001792:Blood Platelets / Q000166:cytology* / Q000378:metabolism; D018929:Cell Culture Techniques; D002454:Cell Differentiation; D006801:Humans; D036341:Intercellular Signaling Peptides and Proteins / Q000378:metabolism; D007962:Leukocytes / Q000166:cytology / Q000378:metabolism; D008297:Male; D059630:Mesenchymal Stem Cells / Q000166:cytology* / Q000378:metabolism; D010012:Osteogenesis; D053657:Platelet-Rich Plasma / Q000378:metabolism
chemical_list: D036341:Intercellular Signaling Peptides and Proteins