title: Basic studies on the clinical applications of platelet-rich plasma.
abstract: Platelets, which contain many growth factors such as platelet-derived growth factor (PDGF) and transforming growth factor-beta (TGF-beta), are being used in clinical applications as platelet-rich plasma (PRP). Only a few studies, however, have been conducted on the growth factors present in PRP and on the clinical applications using the drug delivery system (DDS). For the purpose of clinical application, we first modified the PRP preparation method and assessed the amounts of growth factors contained in the human platelet concentrates. Furthermore, we assessed fibrin glue as a DDS of platelet concentrates. Platelet precipitations were made by twice centrifuging human whole blood. The precipitated platelet was resuspended to yield the platelet concentrates. The growth factor concentrations were measured. Fibrin glue sheets containing this platelet concentrate were implanted in rabbit pinna and samples were obtained for immunostaining (anti-PDGF antibody) to assess the use of PRP over time using the fibrin glue as the DDS. The mean concentration of growth factors present in the platelet concentrates was three times or greater than that of conventional PRP. Furthermore, the results indicated that when the platelet concentrate was used with fibrin glue as a carrier, the contents were released over a period of about 1 week. This raises the possibility that this system may be useful in clinical applications.
authors.affiliation: Department of Plastic and Reconstructive Surgery, Keio University School of Medicine, Shinanomachi 35, Shinjuku-ku, Tokyo, 160-8582, Japan. yazawa@sc.itc.keio.ac.jp
authors.forename: Masaki
authors.initials: M
authors.lastname: Yazawa
authors.forename: Hisao
authors.initials: H
authors.lastname: Ogata
authors.forename: Tatsuo
authors.initials: T
authors.lastname: Nakajima
authors.forename: Taisuke
authors.initials: T
authors.lastname: Mori
authors.forename: Naohide
authors.initials: N
authors.lastname: Watanabe
authors.forename: Makoto
authors.initials: M
authors.lastname: Handa
mesh_terms: D000328:Adult; D000818:Animals; D001792:Blood Platelets / Q000378:metabolism*; D001804:Blood Transfusion, Autologous; D002498:Centrifugation; D016503:Drug Delivery Systems; D005260:Female; D015718:Fibrin Tissue Adhesive / Q000378:metabolism; D006133:Growth Substances / Q000378:metabolism; D006801:Humans; D007150:Immunohistochemistry; D008297:Male; D008875:Middle Aged; D010949:Plasma / Q000166:cytology*; D017713:Platelet Transfusion / Q000379:methods*; D010982:Platelet-Derived Growth Factor / Q000096:biosynthesis; D011817:Rabbits; D013997:Time Factors; D016212:Transforming Growth Factor beta / Q000097:blood
chemical_list: D015718:Fibrin Tissue Adhesive; D006133:Growth Substances; D010982:Platelet-Derived Growth Factor; D016212:Transforming Growth Factor beta