Chu C R, Coutts R D, Yoshioka M, Harwood F L, Monosov A Z, Amiel D
University California San Diego, Orthopaedic Connective Tissue Biochemistry, La Jolla 92093-0630, USA.
J Biomed Mater Res. 1995 Sep;29(9):1147-54. doi: 10.1002/jbm.820290915.
Efforts to expand treatment options for articular cartilage repair have increasingly focused on the implantation of cell-polymer constructs. The purpose of this study is to determine the suitability of porous D,D-L,L-polylactic acid as a carrier for delivering repair cells obtained from rib perichondrium into full-thickness articular cartilage defects. In vitro characterization of perichondrocyte-polylactic acid composite grafts was combined with in vivo assessment of the early articular cartilage repair in a clinically relevant model. Using a fluorescent double-stain protocol to visualize live and dead cells in situ, primary cells cultured from perichondrium were found to be capable of attaching to and surviving within a porous D,D-L,L-polylactic acid matrix. These perichondrocyte-polylactic acid composite grafts were then implanted within osteochondral defects drilled into the left medial femoral condyles of 16 adult New Zealand white rabbits. Experimental animals were sacrificed 6 weeks after implantation and the repair tissue was evaluated grossly, histologically, and biochemically. Grossly, 96% (15/16) of the experimental animals demonstrated repairs consisting of a smooth, firm neocartilage which appeared similar in color and texture to the surrounding articular surface. Matrix staining for cartilaginous protein was seen surrounding chondrocyte-like cells in the cartilage regions of the repair. Cellular alignment was found to be related to scaffold architecture. These results suggest that scaffolds composed of porous D,D-L,L-polylactic acid support the growth of cartilaginous repair tissue and are compatible with both in vitro and in vivo survival of chondrogenic cells.
扩大关节软骨修复治疗选择的努力越来越多地集中在细胞-聚合物构建体的植入上。本研究的目的是确定多孔D，D-L，L-聚乳酸作为载体将从肋软骨膜获得的修复细胞递送至全层关节软骨缺损处的适用性。软骨细胞-聚乳酸复合移植物的体外特性表征与在临床相关模型中对早期关节软骨修复的体内评估相结合。使用荧光双染方案原位可视化活细胞和死细胞，发现从软骨膜培养的原代细胞能够附着在多孔D，D-L，L-聚乳酸基质中并在其中存活。然后将这些软骨细胞-聚乳酸复合移植物植入16只成年新西兰白兔左内侧股骨髁钻取的骨软骨缺损内。植入后6周处死实验动物，对修复组织进行大体、组织学和生化评估。大体上，96%（15/16）的实验动物显示修复组织由光滑、坚实的新软骨组成，其颜色和质地与周围关节表面相似。在修复组织的软骨区域，软骨样细胞周围可见软骨蛋白的基质染色。发现细胞排列与支架结构有关。这些结果表明，由多孔D，D-L，L-聚乳酸组成的支架支持软骨修复组织的生长，并且与软骨生成细胞的体外和体内存活相容。
