title: Autologous fibrin matrices: a potential source of biological mediators that modulate tendon cell activities.
abstract: The use of autologous fibrin matrices has been proposed as a therapeutic strategy for the local and physiological delivery of growth factors in the treatment of several clinical conditions requiring tendon healing or tendon graft remodelling. In the present work, we investigated the proliferation, synthesis of type-I collagen and angiogenic factors by tendon cells seeded on platelet-rich (PR) and platelet-poor (PP) matrices. Furthermore, in vivo cellular and vascular effects of each treatment were examined after infiltration in Achilles tendon in sheep. Results showed that the presence of platelets within the fibrin matrices increased significantly the proliferation of tendon cells. Additionally, cultured tendon cells synthesised type I collagen and angiogenic factors such as VEGF and HGF. The synthesis of VEGF, but not of HGF, was significantly higher when platelets were present within the matrix. In the sheep model, the injection of pre-clotted plasma within tendons increased cellular density and promoted neovascularization. These results indicate that administration of fibrin matrices is a safe and easy strategy that may open new avenues for enhancing tissue healing and remodelling and influences the process of regeneration in clinical situations characterised by a poor healing outcome.
authors.affiliation: Biotechnology Institute I MAS D, San Antonio 15, 01005 Vitoria, Spain.
authors.forename: Eduardo
authors.initials: E
authors.lastname: Anitua
authors.forename: Mikel
authors.initials: M
authors.lastname: Sanchez
authors.forename: Alan T
authors.initials: AT
authors.lastname: Nurden
authors.forename: Mar
authors.initials: M
authors.lastname: Zalduendo
authors.forename: Maria
authors.initials: M
authors.lastname: de la Fuente
authors.forename: Gorka
authors.initials: G
authors.lastname: Orive
authors.forename: Juan
authors.initials: J
authors.lastname: Azofra
authors.forename: Isabel
authors.initials: I
authors.lastname: Andia
mesh_terms: D000125:Achilles Tendon / Q000166:cytology*; D000818:Animals; D001672:Biocompatible Materials / Q000737:chemistry / Q000378:metabolism; D001792:Blood Platelets / Q000378:metabolism; D018929:Cell Culture Techniques; D049109:Cell Proliferation; D002478:Cells, Cultured; D024042:Collagen Type I / Q000378:metabolism; D005109:Extracellular Matrix / Q000737:chemistry*; D005337:Fibrin / Q000737:chemistry* / Q000378:metabolism; D017228:Hepatocyte Growth Factor / Q000378:metabolism; D006801:Humans; D008422:Materials Testing; D012756:Sheep; D016212:Transforming Growth Factor beta / Q000378:metabolism; D053773:Transforming Growth Factor beta1; D042461:Vascular Endothelial Growth Factor A / Q000378:metabolism
chemical_list: D001672:Biocompatible Materials; D024042:Collagen Type I; C066855:HGF protein, human; C508960:TGFB1 protein, human; D016212:Transforming Growth Factor beta; D053773:Transforming Growth Factor beta1; D042461:Vascular Endothelial Growth Factor A; D017228:Hepatocyte Growth Factor; D005337:Fibrin