title: Prefabricated, ear-shaped cartilage tissue engineering by scaffold-free porcine chondrocyte membrane.
abstract: BACKGROUND
  Ear defects caused by traumatic injury, tumor ablation, and congenital deficiency are still challenging problems for the plastic and reconstructive surgeon. The authors developed a scaffold-free, ear-shaped cartilage by tailoring a multilayered chondrocyte membrane on an ear-shaped titanium alloy model and investigated the possibility of long-term ear-shaped maintenance in nude mice.
  
  
  METHODS
  High-density chondrocytes (approximately 30 × 10 cells) were seeded to produce chondrocyte membranes after cultivation under chondrogenic medium for 2 weeks. Then, three-layer chondrocyte membranes were tailored on the ear-shaped titanium mold and fixed by 6-0 nylon. The constructs were implanted onto the dorsal pockets of nude mice for 8 and 24 weeks. The chondrocyte membrane, 8- and 24-week implants were analyzed by safranin O, toluidine blue, elastica van Gieson, and collagen type II immunohistochemistry stains and quantitative measurement of glycosaminoglycan and total collagen compared with native cartilage. Mechanical strength was compared by compressive Young's modulus.
  
  
  RESULTS
  Results showed that the chondrocyte membrane was durable and nonfragile and easily manipulated by forceps. The composite of chondrocyte membrane and titanium alloy maintained the stable ear-like shape after 8 and 24 weeks of subcutaneous implantation. Histologic examination verified that the newly formed tissue at the implant construct was elastic cartilage at both 8 and 24 weeks by safranin O, toluidine blue, elastica van Gieson, and collagen type II immunohistochemistry stains. The Young's modulus was only half of and similar to normal cartilage in 8- and 24-week implants, respectively.
  
  
  CONCLUSIONS
  This study demonstrated that an ear-shaped elastic cartilage could be regenerated by a scaffold-free chondrocyte membrane shaped by a prefabricated, three-dimensional, ear-shaped titanium mold.
authors: Shanghai, People's Republic of China; and Taoyuan, Taiwan From the Department of Plastic and Reconstructive Surgery, Shanghai Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai Key Laboratory of Tissue Engineering, National Tissue Engineering Center of China; and the Department of Plastic and Reconstructive Surgery, Craniofacial Research Center, Chang Gung Memorial Hospital, College of Medicine, Chang Gung University.
authors: Han Tsung
authors: HT
authors: Liao
authors: Rui
authors: R
authors: Zheng
authors: Wei
authors: W
authors: Liu
authors: Wen Jie
authors: WJ
authors: Zhang
authors: Yilin
authors: Y
authors: Cao
authors: Guangdong
authors: G
authors: Zhou
mesh_terms: D000497:Alloys; D000818:Animals; D000831:Animals, Newborn; D002462:Cell Membrane / Q000648:ultrastructure*; D002478:Cells, Cultured; D019902:Chondrocytes / Q000648:ultrastructure*; D003094:Collagen / Q000096:biosynthesis; D016895:Culture Media, Serum-Free; D004431:Ear, External; D051472:Elastic Cartilage / Q000166:cytology*; D055119:Elastic Modulus; D006025:Glycosaminoglycans / Q000096:biosynthesis; D006801:Humans; D008422:Materials Testing; D051379:Mice; D008819:Mice, Nude; D019736:Prostheses and Implants; D015607:Stents; D034421:Sus scrofa; D013552:Swine; D023822:Tissue Engineering / Q000379:methods*; D014025:Titanium
chemical_list: D000497:Alloys; D016895:Culture Media, Serum-Free; D006025:Glycosaminoglycans; D003094:Collagen; D014025:Titanium
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