title: Optimization of human tendon tissue engineering: peracetic acid oxidation for enhanced reseeding of acellularized intrasynovial tendon.
abstract: BACKGROUND
  Tissue engineering of human flexor tendons combines tendon scaffolds with recipient cells to create complete cell-tendon constructs. Allogenic acellularized human flexor tendon has been shown to be a useful natural scaffold. However, there is difficulty repopulating acellularized tendon with recipient cells, as cell penetration is restricted by a tightly woven tendon matrix. The authors evaluated peracetic acid treatment in optimizing intratendinous cell penetration.
  
  
  METHODS
  Cadaveric human flexor tendons were harvested, acellularized, and divided into experimental groups. These groups were treated with peracetic acid in varying concentrations (2%, 5%, and 10%) and for varying time periods (4 and 20 hours) to determine the optimal treatment protocol. Experimental tendons were analyzed for differences in tendon microarchitecture. Additional specimens were reseeded by incubation in a fibroblast cell suspension at 1 × 10(6) cells/ml. This group was then analyzed for reseeding efficacy. A final group underwent biomechanical studies for strength.
  
  
  RESULTS
  The optimal treatment protocol comprising peracetic acid at 5% concentration for 4 hours produced increased scaffold porosity, improving cell penetration and migration. Treated scaffolds did not show reduced collagen or glycosaminoglycan content compared with controls (p = 0.37 and p = 0.65, respectively). Treated scaffolds were cytotoxic to neither attached cells nor the surrounding cell suspension. Treated scaffolds also did not show inferior ultimate tensile stress or elastic modulus compared with controls (p = 0.26 and p = 0.28, respectively).
  
  
  CONCLUSIONS
  Peracetic acid treatment of acellularized tendon scaffolds increases matrix porosity, leading to greater reseeding. It may prove to be an important step in tissue engineering of human flexor tendon using natural scaffolds.
authors.affiliation: Palo Alto, Calif. From the Division of Plastic and Reconstructive Surgery, Stanford University Medical Center, and the Section of Plastic Surgery, Veterans Affairs Palo Alto Health Care System.
authors.forename: Colin Y L
authors.initials: CYL
authors.lastname: Woon
authors.forename: Brian C
authors.initials: BC
authors.lastname: Pridgen
authors.forename: Armin
authors.initials: A
authors.lastname: Kraus
authors.forename: Sina
authors.initials: S
authors.lastname: Bari
authors.forename: Hung
authors.initials: H
authors.lastname: Pham
authors.forename: James
authors.initials: J
authors.lastname: Chang
mesh_terms: D001696:Biomechanical Phenomena; D002102:Cadaver; D002478:Cells, Cultured; D005347:Fibroblasts / Q000187:drug effects / Q000378:metabolism* / Q000637:transplantation; D006801:Humans; D016877:Oxidants / Q000494:pharmacology*; D010084:Oxidation-Reduction / Q000187:drug effects*; D010463:Peracetic Acid / Q000493:pharmacokinetics*; D013710:Tendons / Q000166:cytology / Q000378:metabolism / Q000637:transplantation*; D023822:Tissue Engineering / Q000379:methods*
chemical_list: D016877:Oxidants; D010463:Peracetic Acid