title: Repair of Achilles tendon defect with autologous ASCs engineered tendon in a rabbit model.
abstract: Adipose derived stem cells (ASCs) are an important cell source for tissue regeneration and have been demonstrated the potential of tenogenic differentiation in vitro. This study explored the feasibility of using ASCs for engineered tendon repair in vivo in a rabbit Achilles tendon model. Total 30 rabbits were involved in this study. A composite tendon scaffold composed of an inner part of polyglycolic acid (PGA) unwoven fibers and an outer part of a net knitted with PGA/PLA (polylactic acid) fibers was used to provide mechanical strength. Autologous ASCs were harvested from nuchal subcutaneous adipose tissues and in vitro expanded. The expanded ASCs were harvested and resuspended in culture medium and evenly seeded onto the scaffold in the experimental group, whereas cell-free scaffolds served as the control group. The constructs of both groups were cultured inside a bioreactor under dynamic stretch for 5 weeks. In each of 30 rabbits, a 2 cm defect was created on right side of Achilles tendon followed by the transplantation of a 3 cm cell-seeded scaffold in the experimental group of 15 rabbits, or by the transplantation of a 3 cm cell-free scaffold in the control group of 15 rabbits. Animals were sacrificed at 12, 21 and 45 weeks post-surgery for gross view, histology, and mechanical analysis. The results showed that short term in vitro culture enabled ASCs to produce matrix on the PGA fibers and the constructs showed tensile strength around 50 MPa in both groups (p > 0.05). With the increase of implantation time, cell-seeded constructs gradually form neo-tendon and became more mature at 45 weeks with histological structure similar to that of native tendon and with the presence of bipolar pattern and D-periodic structure of formed collagen fibrils. Additionally, both collagen fibril diameters and tensile strength increased continuously with significant difference among different time points (p < 0.05). In contrast, cell-free constructs failed to form good quality tendon tissue with fibril structure observable only at 45 weeks. There were significant differences in both collagen fibril diameter and tensile strength between two groups at all examined time points (p < 0.05). The results of this study support that ASCs are likely to be a potential cell source for in vivo tendon engineering and regeneration.
authors: Department of Plastic and Reconstructive Surgery, Shanghai Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai Key Laboratory of Tissue Engineering Research, National Tissue Engineering Center of China, Shanghai, PR China.
authors: Dan
authors: D
authors: Deng
authors: Department of Plastic and Reconstructive Surgery, Shanghai Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai Key Laboratory of Tissue Engineering Research, National Tissue Engineering Center of China, Shanghai, PR China.
authors: Wenbo
authors: W
authors: Wang
authors: Department of Plastic and Reconstructive Surgery, Shanghai Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai Key Laboratory of Tissue Engineering Research, National Tissue Engineering Center of China, Shanghai, PR China.
authors: Bin
authors: B
authors: Wang
authors: College of Textiles, Donghua University, Shanghai, PR China. Electronic address: phzh@dhu.edu.cn.
authors: Peihua
authors: P
authors: Zhang
authors: Department of Plastic and Reconstructive Surgery, Shanghai Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai Key Laboratory of Tissue Engineering Research, National Tissue Engineering Center of China, Shanghai, PR China.
authors: Guangdong
authors: G
authors: Zhou
authors: Department of Plastic and Reconstructive Surgery, Shanghai Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai Key Laboratory of Tissue Engineering Research, National Tissue Engineering Center of China, Shanghai, PR China.
authors: Wen Jie
authors: WJ
authors: Zhang
authors: Department of Plastic and Reconstructive Surgery, Shanghai Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai Key Laboratory of Tissue Engineering Research, National Tissue Engineering Center of China, Shanghai, PR China.
authors: Yilin
authors: Y
authors: Cao
authors: Department of Plastic and Reconstructive Surgery, Shanghai Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai Key Laboratory of Tissue Engineering Research, National Tissue Engineering Center of China, Shanghai, PR China. Electronic address: liuwei_2000@yahoo.com.
authors: Wei
authors: W
authors: Liu
mesh_terms: D000125:Achilles Tendon / Q000166:cytology / Q000293:injuries / Q000502:physiology*; D000273:Adipose Tissue / Q000166:cytology*; D000818:Animals; D002454:Cell Differentiation; D002478:Cells, Cultured; D019344:Lactic Acid / Q000737:chemistry; D011091:Polyesters; D011100:Polyglycolic Acid / Q000737:chemistry; D011108:Polymers / Q000737:chemistry; D011817:Rabbits; D033581:Stem Cell Transplantation; D013234:Stem Cells / Q000166:cytology*; D023822:Tissue Engineering / Q000379:methods; D054457:Tissue Scaffolds / Q000737:chemistry*; D014945:Wound Healing
chemical_list: D011091:Polyesters; D011108:Polymers; D011100:Polyglycolic Acid; D019344:Lactic Acid; C033616:poly(lactide)
keywords: ASCs; In vivo repair; PGA/PLA scaffold; Rabbit Achilles tendon