Background: Platelet preparations for tissue healing are usually preactivated before application to deliver concentrated growth factors. In this study, the authors investigated the differences between nonactivated and thrombin-activated platelets in wound healing.
Methods: The healing effects (i.e., wound closure, myofibroblast formation, and angiogenesis) of nonactivated and thrombin-activated platelets were compared in experimental wounds in diabetic (db/db) animals. In vitro, fibroblast phenotype and function were tested in response to platelets and activated platelets. No treatment served as a negative control.
Results: Wounds treated with platelets reached 90 percent closure after 15 days, faster than activated platelets (26 days), and with higher levels of myofibroblasts and angiogenesis. In vitro, platelets enhanced cell migration and induced two-fold higher myofibroblast differentiation and contraction compared with activated platelets.
Conclusions: Platelets stimulate wound healing more efficiently compared with activated platelets by enhancing fibroblast differentiation and contractile function. Similar levels of growth factors may induce different biological effects when delivered “on demand” rather than in an initial bolus.
Lausanne and Geneva, Switzerland; Boston, Mass.; and Toronto, Ontario, Canada
From the Department of Plastic Surgery, University Hospitals of Lausanne; the Department of Plastic, Reconstructive, and Aesthetic Surgery, University Hospitals of Geneva and Faculty of Medicine, University of Geneva; the Laboratory of Cell Biophysics, Ecole Polytechnique Fédérale de Lausanne; the Tissue Engineering and Wound Healing Laboratory, Brigham and Women's Hospital; and the Laboratory of Tissue Repair and Regeneration, Matrix Dynamics Group, Faculty of Dentistry, University of Toronto.
Received for publication May 3, 2011; accepted July 11, 2011.
Disclosure: The authors have no financial interest in any of the products or devices mentioned in this article.
Giorgio Pietramaggiori, M.D., Ph.D.; Service de chirurgie plastique et reconstructive, Département de Chirurgie, Centre Hospitalier Universitaire Vaudois, Rue du Bugnon 46, 1011 Lausanne, Switzerland, firstname.lastname@example.org
Brigitte Pittet, M.D.; Service de chirurgie plastique, reconstructive et esthétique, Département de Chirurgie, Hôpitaux Universitaires de Genève, Gabrielle-Perret-Gentil 4, 1211 Genève 14, Switzerland, email@example.com