title: Platelet-rich plasma enhances the initial mobilization of circulation-derived cells for tendon healing.
abstract: Circulation-derived cells play a crucial role in the healing processes of tissue. In early phases of tendon healing processes, circulation-derived cells temporarily exist in the wounded area to initiate the healing process and decrease in number with time. We assumed that a delay of time-dependent decrease in circulation-derived cells could improve the healing of tendons. In this study, we injected platelet-rich plasma (PRP) containing various kinds of growth factors into the wounded area of the patellar tendon, and compared the effects on activation of circulation-derived cells and enhancement of tendon healing with a control group (no PRP injection). To follow the circulation-derived cells, we used a green fluorescent protein (GFP) chimeric rat expressing GFP in the circulating cells and bone marrow cells. In the PRP group, the numbers of GFP-positive cells and heat-shock protein (HSP47; collagen-specific molecular chaperone)-positive cells were significantly higher than in the control group at 3 and 7 days after injury. At the same time, the immunoreactivity for types I and III collagen was higher in the PRP group than in the control group at early phase of tendon healing. These findings suggest that locally injected PRP is useful as an activator of circulation-derived cells for enhancement of the initial tendon healing process.
authors.affiliation: Department of Orthopaedics, Graduate School of Medical Science, Kyoto Prefectural University of Medicine, Kyoto, Japan. kajiyoshi777@yahoo.co.jp
authors.forename: Yoshiteru
authors.initials: Y
authors.lastname: Kajikawa
authors.forename: Toru
authors.initials: T
authors.lastname: Morihara
authors.forename: Hirotaka
authors.initials: H
authors.lastname: Sakamoto
authors.forename: Ken-ichi
authors.initials: K
authors.lastname: Matsuda
authors.forename: Yasushi
authors.initials: Y
authors.lastname: Oshima
authors.forename: Atsuhiko
authors.initials: A
authors.lastname: Yoshida
authors.forename: Masateru
authors.initials: M
authors.lastname: Nagae
authors.forename: Yuji
authors.initials: Y
authors.lastname: Arai
authors.forename: Mitsuhiro
authors.initials: M
authors.lastname: Kawata
authors.forename: Toshikazu
authors.initials: T
authors.lastname: Kubo
mesh_terms: D000818:Animals; D001775:Blood Circulation; D001792:Blood Platelets / Q000378:metabolism; D001854:Bone Marrow Cells / Q000473:pathology; D016026:Bone Marrow Transplantation; D002465:Cell Movement; D049109:Cell Proliferation; D046528:Chimerism; D003094:Collagen / Q000378:metabolism; D005260:Female; D049452:Green Fluorescent Proteins / Q000378:metabolism; D050958:HSP47 Heat-Shock Proteins / Q000378:metabolism; D007150:Immunohistochemistry; D036341:Intercellular Signaling Peptides and Proteins / Q000378:metabolism; D008264:Macrophages / Q000166:cytology / Q000378:metabolism; D016253:Microscopy, Immunoelectron; D010329:Patella / Q000473:pathology / Q000648:ultrastructure; D053657:Platelet-Rich Plasma / Q000378:metabolism*; D051381:Rats; D017207:Rats, Sprague-Dawley; D013708:Tendon Injuries / Q000473:pathology / Q000503:physiopathology; D013710:Tendons / Q000473:pathology* / Q000648:ultrastructure; D014945:Wound Healing
chemical_list: D050958:HSP47 Heat-Shock Proteins; D036341:Intercellular Signaling Peptides and Proteins; C494662:Serpinh1 protein, rat; D049452:Green Fluorescent Proteins; D003094:Collagen