title: Morphologic features of biocompatibility and neoangiogenesis onto a biodegradable tracheal prosthesis in an animal model.
abstract: We evaluated a newly designed bioresorbable polymer (Degrapol) tracheal prosthesis in an in-vivo angiogenesis-inducing animal model focusing on the specific tissue reaction, the neo-angiogenesis and also the eventual cathepsin B role during the polymer degradation. Fifteen rabbits were divided into three groups (2, 6 and 8 weeks) and our tube-shaped porous prosthesis was implanted using the common carotid artery and the internal jugular vein as vascular pedicle. Optical and electron microscopy, immunohistochemistry and immunocytochemistry were performed at the end of each period, showing cells and fibrils, in direct contact with the Degrapol scaffold, strongly increased with time. Blood vessel neoformation was visible with CD31 expression localized at the endothelial cells forming the neovascular walls. Over time many of them differentiate in muscle fibers as validated by the expression of alpha-smooth muscle actin (SMA). Few inflammatory cells, expressing CD14, were visible while most cells adopting a pronounced spreading phenotype showed a strong positivity for cathepsin B. We concluded that this bioresorbable polymer provided a good substrate for fibrous tissue deposition with an excellent degree of neo-angiogenesis. Also, cathepsin B seems to contribute to the polymer degradation and particularly to neovascularization by stimulating capillary-like tubular structures and cell proliferation.
authors.affiliation: Department of Veterinary Clinical Science, Faculty of Veterinary Medicine, University of Milan, Milano, Italy.
authors.forename: Stefano
authors.initials: S
authors.lastname: Brizzola
authors.forename: Magda
authors.initials: M
authors.lastname: de Eguileor
authors.forename: Tiziana
authors.initials: T
authors.lastname: Brevini
authors.forename: Annalisa
authors.initials: A
authors.lastname: Grimaldi
authors.forename: Terenzio
authors.initials: T
authors.lastname: Congiu
authors.forename: Peter
authors.initials: P
authors.lastname: Neuenschwander
authors.forename: Fabio
authors.initials: F
authors.lastname: Acocella
mesh_terms: D020341:Absorbable Implants; D000818:Animals; D001672:Biocompatible Materials; D002401:Cathepsin B / Q000378:metabolism; D002454:Cell Differentiation; D002465:Cell Movement; D042783:Endothelial Cells / Q000378:metabolism; D005109:Extracellular Matrix / Q000378:metabolism; D019084:Fluorescent Antibody Technique, Indirect; D008422:Materials Testing; D008855:Microscopy, Electron, Scanning; D046529:Microscopy, Electron, Transmission; D023421:Models, Animal; D032389:Myocytes, Smooth Muscle / Q000378:metabolism; D018919:Neovascularization, Physiologic; D011091:Polyesters / Q000737:chemistry*; D011140:Polyurethanes / Q000737:chemistry*; D016062:Porosity; D011474:Prosthesis Design; D019919:Prosthesis Implantation; D011817:Rabbits; D013194:Staining and Labeling; D054457:Tissue Scaffolds; D014132:Trachea / Q000098:blood supply* / Q000201:enzymology / Q000601:surgery* / Q000648:ultrastructure
chemical_list: D001672:Biocompatible Materials; C104154:DegraPol; D011091:Polyesters; D011140:Polyurethanes; D002401:Cathepsin B