Cell culture of human nasoseptal chondrocytes using bioflow reaction

本研究评估了将b-成纤维细胞生长因子植入明胶微球以实现缓慢生长因子释放以增强体内软骨形成反应的有效性。而在溶液中注射~(125)I标记b-成纤维细胞生长因子可迅速从注射部位清除(24小时后仅残留3%)，而与明胶微球复合后，3天和14天分别有44%和18%的b-成纤维细胞生长因子保留。分离犬软骨细胞，体外培养于耳形聚丙交酯/卡丙内酯共聚物上1周后，植入裸鼠背侧皮下组织，植入游离溶液或明胶微球中。第三组在软骨细胞共聚物植入前4天在明胶微球中预先注射b-FGF。在术后5周和10周，复合b-FGF微球的植入物显示出最好的软骨形成特征：良好的外形和生物力学特性，强烈的组织学异染性，丰富的周围组织的血管形成，以及II型胶原(软骨标记)和因子VIII相关抗原(血管标记)的基因表达增加。在植入部位预先给予b-成纤维细胞生长因子微球的情况下，种植体的结构也不能保持，血管形成减少和异色现象也很明显。总之，这些发现表明，b-foe的持续释放增加了组织工程化软骨构建中的新生血管和软骨生成。

This study evaluated the effectiveness of b-FGF impregnated in gelatin microspheres to achieve slow growth factor release for augmenting the in vivo chondrogenic response. Whereas ^<125>I-labeled b-FGF injected in solution showed rapid in vivo clearance from the injection site (only 3% residual after 24 hours), when incorporated into gelatin microspheres, 44% and 18% of the b-FGF remained at 3 and 14 days, respectively. Canine chondrocytes were isolated and grown in vitro onto ear-shaped poly-lactide/capro-lactone copolymers for one week, then implanted into the dorsal subcutaneous tissue of nude mice ; implants contained b-FGF either in free solution or in gelatin microspheres. A third group underwent pre-injection of b-FGF in gelatin microspheres four days before chondrocyte-copolymer implantation. The implants with b-FGF-incorporated microspheres showed the greatest chondrogenic characteristics at 5 and 10 weeks postoperatively : good shape and biomechanical trait retention, strong (histologic) metachromasia, rich vascularization of surrounding tissues, and increased gene expression for type II collagen (cartilage marker) and factor VIII-related antigen (vascular marker). In the case of implant site pre-administration with b-FGF-impregnated microspheres, the implant architecture was not maintained as well, and reduced vascularization and metachromasia was also apparent. In conclusion, these findings indicate that a sustained release of b-FOE augments neovascularization and chondrogenesis in a tissue-engineered cartilage construct.