Cell culture of human nasoseptal chondrocytes using bioflow reaction

本研究评估了b-FGF浸没在明胶微球中的有效性，以实现生长因子的缓慢释放，以增强体内软骨形成反应。^<125> i标记的b-FGF在溶液中注射后显示出快速的体内清除（24小时后仅残留3%），当加入明胶微球时，44%和18%的b-FGF在3天和14天分别残留。分离犬软骨细胞，在耳形聚乳酸/己内酯共聚物上体外培养1周，植入裸鼠背部皮下组织；植入物中含有游离溶液或明胶微球中的b-FGF。第三组在软骨细胞-共聚物植入前4天在明胶微球中预注射b-FGF。植入b- fgf微球的植入物在术后5周和10周表现出最大的软骨形成特征：良好的形状和生物力学特征保留，强（组织学）异色，周围组织丰富的血管化，II型胶原（软骨标志物）和viii因子相关抗原（血管标志物）的基因表达增加。在植入体部位预先使用b- fgf浸染微球的情况下，植入体的结构也没有得到维持，血管化减少和色差也很明显。总之，这些发现表明，b-FOE的持续释放增强了组织工程软骨构建中的新生血管和软骨形成。

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.