title: Effect of laser perforation on the remodeling of acellular matrix grafts.
abstract: Autologous cells migrate only slightly into acellular matrix grafts. This study was carried out in small-diameter, allogeneic matrix grafts to investigate the effects on cell repopulation and remodeling caused by increased wall porosity induced by laser perforation. Allogeneic ovine carotid arteries were decellularized by dye-mediated photooxidation (Photofix). Matrix grafts (10 cm x 4 mm i.d.) were perforated with holes of 50 microm diameter at a density of 50 holes/cm(2) using a Ti-sapphire laser. The grafts were implanted in the carotid arteries of 10 sheep and were compared to nonperforated grafts implanted contralaterally. The prostheses were retrieved after 6 weeks or 3 or 6 months following implantation and were evaluated by histologic examination, immunohistochemical staining, and scanning electron microscopy. All grafts, except one of the perforated specimens, remained patent. Perforated implants, examined at 6 weeks, showed faster recellularization with endothelial cells than did the corresponding contralateral controls. Perforated grafts, examined at 6 months, showed a significantly thicker neointima and clear signs of neovascularization: endothelial cells, basal lamina, elastic fibers, circular and longitudinally orientated smooth muscle cells in comparison to nonperforated specimens. Repopulation of the decellularized matrix with host cells was higher in the perforated than in the nonperforated prostheses. These results suggest that the increased matrix porosity induced by laser perforation promotes graft remodeling and reconstitution with host cells.
authors.affiliation: Institute of Biomedical Research, Medical University of Vienna, Austria. helga.bergmeister@meduniwien.ac.at
authors.forename: Helga
authors.initials: H
authors.lastname: Bergmeister
authors.forename: Peter
authors.initials: P
authors.lastname: Boeck
authors.forename: Marie-Theres
authors.initials: MT
authors.lastname: Kasimir
authors.forename: Tatjana
authors.initials: T
authors.lastname: Fleck
authors.forename: Florian
authors.initials: F
authors.lastname: Fitzal
authors.forename: Wolfgang
authors.initials: W
authors.lastname: Husinsky
authors.forename: Martina
authors.initials: M
authors.lastname: Mittlboeck
authors.forename: Hans Georg
authors.initials: HG
authors.lastname: Stoehr
authors.forename: Udo
authors.initials: U
authors.lastname: Losert
authors.forename: Ernst
authors.initials: E
authors.lastname: Wolner
authors.forename: Martin
authors.initials: M
authors.lastname: Grabenwoeger
mesh_terms: D000818:Animals; D001672:Biocompatible Materials / Q000737:chemistry*; D001705:Bioprosthesis; D001807:Blood Vessel Prosthesis; D002339:Carotid Arteries / Q000473:pathology*; D049109:Cell Proliferation; D004730:Endothelium, Vascular; D007150:Immunohistochemistry; D007834:Lasers; D008027:Light; D008855:Microscopy, Electron, Scanning; D010100:Oxygen / Q000378:metabolism; D012756:Sheep; D014025:Titanium; D014654:Vascular Patency
chemical_list: D001672:Biocompatible Materials; D014025:Titanium; D010100:Oxygen