title: In vivo application of tissue-engineered blood vessels of bacterial cellulose as small arterial substitutes: proof of concept?
abstract: BACKGROUND
  Tissue-engineered blood vessels (TEBVs) represent an innovative approach for overcoming reconstructive problems associated with vascular diseases by providing small-caliber vascular grafts. This study aimed to evaluate a novel biomaterial of bacterially synthesized cellulose (BC) as a potential scaffold for small-diameter TEBV.
  
  
  METHODS
  Small-diameter blood vessels with a supramolecular fiber network structure consisting of tubular hydrogels from biodesigned cellulose were created using Gluconacetobacter strains and Matrix reservoir technology. BC tubes (length: 100 mm, inner diameter: 4.0-5.0 mm) were applied to replace the carotid arteries of 10 sheep for a period of 3 mo to gain further insights into (a) functional (in vivo) performance, (b) ability of providing a scaffold for the neoformation of a vascular wall and (c) their proinflammatory potential, and the (d) technical feasibility of the procedure.
  
  
  RESULTS
  Preoperative analysis revealed a bursting strength of the grafts of approximately 800 mm Hg and suture retention strength of 4-5 N. Postexplantation analysis showed a patency rate of 50% (n = 5) and physiological performance of the patent grafts at 4, 8, and 12 wk postoperatively, compared with native arteries. Histologic analysis revealed a neoformation of a vascular wall-like structure along the BC scaffold consisting of immigrated vascular smooth muscle cells and a homogeneous endothelialization of the inner graft surface without signs of prothrombogenic or inflammatory potential. Scanning electron microscopy revealed a confluent luminal endothelial cell layer and the immigration of vascular smooth muscle cells into the BC matrix.
  
  
  CONCLUSIONS
  BC grafts provide a scaffold for the neoformation of a three-layered vascular wall exhibit attractive properties for their use in future TEBV programs for cardiovascular surgery.
authors.affiliation: Department of Cardiothoracic Surgery, University Hospital of Cologne, Cologne, Germany. Electronic address: maximilian.scherner@uk-koeln.de.
authors.forename: Maximilian
authors.initials: M
authors.lastname: Scherner
authors.affiliation: Department of Cardiothoracic Surgery, University Hospital of Cologne, Cologne, Germany.
authors.forename: Stefanie
authors.initials: S
authors.lastname: Reutter
authors.affiliation: Department of Organic Chemistry, Friedrich Schiller University Jena, Jena, Germany.
authors.forename: Dieter
authors.initials: D
authors.lastname: Klemm
authors.affiliation: Department of Experimental Medicine, University Hospital of Cologne, Cologne, Germany.
authors.forename: Anja
authors.initials: A
authors.lastname: Sterner-Kock
authors.affiliation: Department of Experimental Medicine, University Hospital of Cologne, Cologne, Germany.
authors.forename: Maria
authors.initials: M
authors.lastname: Guschlbauer
authors.affiliation: Department of Organic Chemistry, Friedrich Schiller University Jena, Jena, Germany.
authors.forename: Thomas
authors.initials: T
authors.lastname: Richter
authors.affiliation: Department of Cardiothoracic Surgery, University Hospital of Cologne, Cologne, Germany.
authors.forename: Georg
authors.initials: G
authors.lastname: Langebartels
authors.affiliation: Department of Cardiothoracic Surgery, University Hospital of Cologne, Cologne, Germany.
authors.forename: Navid
authors.initials: N
authors.lastname: Madershahian
authors.affiliation: Department of Cardiothoracic Surgery, University Hospital of Cologne, Cologne, Germany.
authors.forename: Thorsten
authors.initials: T
authors.lastname: Wahlers
authors.affiliation: Department of Cardiothoracic Surgery, University Hospital of Cologne, Cologne, Germany.
authors.forename: Jens
authors.initials: J
authors.lastname: Wippermann
mesh_terms: D000818:Animals; D001160:Arterioles; D001807:Blood Vessel Prosthesis; D019917:Blood Vessel Prosthesis Implantation; D002482:Cellulose; D005240:Feasibility Studies; D005260:Female; D005549:Foreign-Body Reaction; D041822:Gluconacetobacter xylinus; D008422:Materials Testing; D012756:Sheep; D023822:Tissue Engineering; D054457:Tissue Scaffolds; D014654:Vascular Patency
chemical_list: D002482:Cellulose
keywords: Artificial small-diameter vascular grafts; Bacterial cellulose; Vascular surgery; Vascular tissue engineering