title: Tissue Engineering of Tendons: A Comparison of Muscle-Derived Cells, Tenocytes, and Dermal Fibroblasts as Cell Sources.
abstract: BACKGROUND
  The rapid development of tendon tissue-engineering technology may offer an alternative graft for reconstruction of severe tendon losses. One critical factor for tendon tissue engineering is the optimization of seed cells. Little is known about the optimal cell source for engineered tendons. The aim of this study was to compare mouse muscle-derived cells, dermal fibroblasts, and tenocytes and determine the optimal cell source for tendon tissue engineering.
  
  
  METHODS
  Mouse muscle-derived cells, dermal fibroblasts, and tenocytes were isolated and cultured in vitro. At passage 1, cellular morphology, cell proliferation, and tenogenic marker expression were evaluated. After seeding on the polyglycolic acid scaffolds for 2 weeks in vitro and 12 weeks in vivo, histologic qualities, ultrastructure, and biomechanical characteristics were evaluated.
  
  
  RESULTS
  Proliferation and cellular morphology were similar for dermal fibroblasts and tenocytes, whereas muscle-derived cells proliferated faster than the other two groups. With regard to the phenotype difference between them, muscle-derived cells and tenocytes shared the gene expression of SCX, TNMD, GDF-8, and Col-I, but with MyoD gene expression only in muscle-derived cells. In contrast to dermal fibroblast and tenocyte constructed tendons, neotendon with muscle-derived cells exhibited better aligned collagen fibers, more mature collagen fibril structure, and stronger mechanical properties, whereas no significant difference in the dermal fibroblast and tenocyte groups was observed.
  
  
  CONCLUSIONS
  Although dermal fibroblasts are candidates for tendon tissue engineering because they are similar to tenocytes in proliferation and neotendon formation, muscle-derived cells appear to be the most suitable cells for further study and development of engineered tendon.
authors.affiliation: Beijing and Shanghai, People's Republic of China.
authors.forename: Bo
authors.initials: B
authors.lastname: Chen
authors.forename: Jinping
authors.initials: J
authors.lastname: Ding
authors.forename: Wenjie
authors.initials: W
authors.lastname: Zhang
authors.forename: Guangdong
authors.initials: G
authors.lastname: Zhou
authors.forename: Yilin
authors.initials: Y
authors.lastname: Cao
authors.forename: Wei
authors.initials: W
authors.lastname: Liu
authors.forename: Bin
authors.initials: B
authors.lastname: Wang
mesh_terms: D000704:Analysis of Variance; D000818:Animals; D049109:Cell Proliferation; D002478:Cells, Cultured; D004195:Disease Models, Animal; D005347:Fibroblasts / Q000166:cytology; D051379:Mice; D008810:Mice, Inbred C57BL; D008819:Mice, Nude; D032342:Muscle Cells / Q000166:cytology; D011897:Random Allocation; D012680:Sensitivity and Specificity; D012867:Skin / Q000166:cytology; D013708:Tendon Injuries / Q000601:surgery*; D013710:Tendons / Q000166:cytology* / Q000601:surgery; D013718:Tensile Strength; D023822:Tissue Engineering / Q000379:methods*; D054457:Tissue Scaffolds