title: Novel tissue-engineered biodegradable material for reconstruction of vascular wall.
abstract: BACKGROUND
  To solve several problems with artificial grafts, we sought to develop a novel bioengineered material that can promote tissue regeneration without ex vivo cell seeding and that has sufficient durability to be used for artery reconstruction. Here, we tested whether this biodegradable material could accelerate the in situ regeneration of autologous cardiovascular tissue, especially of the arterial wall, in various models of cardiovascular surgeries.
  
  
  METHODS
  The tissue-engineered patch was fabricated by compounding a collagen-microsponge with a biodegradable polymeric scaffold composed of polyglycolic acid knitted mesh, reinforced on the outside with woven polylactic acid. Tissue-engineered patches without precellularization were grafted into the porcine descending aorta (n = 5), the porcine pulmonary arterial trunk (n = 8), or the canine right ventricular outflow tract (as the large graft model; n = 4). Histologic and biochemical assessments were performed 1, 2, and 6 months after the implantation.
  
  
  RESULTS
  There was no thrombus formation in any animal. Two months after grafting, all the grafts showed good in situ cellularization by hematoxylin/eosin and immunostaining. The quantification of the cell population by polymerase chain reaction showed a large number of endothelial and smooth muscle cells 2 months after implantation. In the large graft model, the architecture of the patch was similar to that of native tissue 6 months after implantation.
  
  
  CONCLUSIONS
  A tissue-engineered patch made of our biodegradable polymer and collagen-microsponge provided good in situ regeneration at both the venous and arterial wall, suggesting that this patch can be used as a novel surgical material for the repair of the cardiovascular system.
authors.affiliation: Division of Cardiovascular Surgery, Department of Surgery, Osaka University Graduate School of Medicine, Osaka, Japan.
authors.forename: Shigemitsu
authors.initials: S
authors.lastname: Iwai
authors.forename: Yoshiki
authors.initials: Y
authors.lastname: Sawa
authors.forename: Satoshi
authors.initials: S
authors.lastname: Taketani
authors.forename: Kei
authors.initials: K
authors.lastname: Torikai
authors.forename: Koichiro
authors.initials: K
authors.lastname: Hirakawa
authors.forename: Hikaru
authors.initials: H
authors.lastname: Matsuda
mesh_terms: D020341:Absorbable Implants; D000818:Animals; D004285:Dogs; D009131:Muscle, Smooth, Vascular; D020133:Reverse Transcriptase Polymerase Chain Reaction; D013552:Swine; D023822:Tissue Engineering / Q000379:methods*