Institute of Biomedical Engineering, College of Medicine and College of Engineering, National Taiwan University, Taipei 10051, Taiwan.
Biomaterials. 2012 Jan;33(1):120-7. doi: 10.1016/j.biomaterials.2011.09.042. Epub 2011 Oct 5.
Tissue engineering for cartilage regeneration provides an alternative to surgery for degenerative osteoarthritis. Recently, a highly organized three-dimensional (3D) alginate scaffold was prepared using a microfluidic device; this scaffold is effective for chondrocyte culture in vitro. The performance of this scaffold was further demonstrated; an alginate scaffold seeded with porcine chondrocytes was implanted in the dorsal subcutaneous site of SCID mice. The recipients were sacrificed at 2, 4, and 6 weeks after transplantation. The grafted implants retrieved from the subcutaneous site were analyzed with histologic examinations. Real-time PCR was used to identify the gene expression patterns of the chondrocytes. The hematoxylin and eosin staining showed that the chondrocytes survived normally in SCID mice; cartilage-like structures were formed after 4 weeks implantation. Immunohistochemical staining revealed cells secreted type II collagen, produced glycosaminoglycans (proved by alcian blue stain), and maintained the expression of S-100. On the other hand, the cells were negative for type I and type X collagen staining. PCR showed that the mRNA expressions of aggrecan and type II collagen were up-regulated at weeks two and four, while type I and type X collagen were down-regulated during the study period. In summary, this highly organized 3D alginate scaffold provided a suitable environment and maintained functional phenotypes for chondrocytes in this animal study.
组织工程软骨再生为退行性骨关节炎的手术治疗提供了一种替代方法。最近，使用微流控装置制备了具有高度组织化的三维（3D）海藻酸钠支架；该支架可有效用于体外软骨细胞培养。进一步证明了该支架的性能；将猪软骨细胞接种在海藻酸钠支架上，然后植入 SCID 小鼠的背部皮下部位。移植后 2、4 和 6 周处死受者。从皮下部位取出移植的植入物进行组织学检查。实时 PCR 用于鉴定软骨细胞的基因表达模式。苏木精和伊红染色显示软骨细胞在 SCID 小鼠中正常存活；植入 4 周后形成软骨样结构。免疫组织化学染色显示细胞分泌 II 型胶原，产生糖胺聚糖（经阿利新蓝染色证实），并保持 S-100 的表达。另一方面，细胞对 I 型和 X 型胶原染色呈阴性。PCR 显示，在研究期间，聚集蛋白聚糖和 II 型胶原的 mRNA 表达在第 2 周和第 4 周上调，而 I 型和 X 型胶原的表达下调。总之，在这项动物研究中，这种高度组织化的 3D 海藻酸钠支架为软骨细胞提供了合适的环境并维持了其功能表型。
