含bFGF和bDNF的壳聚糖对大鼠脑皮质损伤的修复研究

Role of bFGF and bDNF-conjugated Chitosan Hydrogel Transplantation in Promoting Recovery of Rat's Pallial Lesion

目的将含碱性成纤维细胞生长因子(bFGF)和脑源性神经营养因子(bDNF)的壳聚糖植于大鼠脑皮层损伤区,观察移植物诱导脑细胞的迁移和促进轴突再生作用。方法在立体定位仪下用显微手术刀剔除脑皮质约2mm×2mm×15mm,立即植入含bFGF和bDNF的壳聚糖,术后2、4、6个月时用组织化学和免疫组织化学方法检测损伤区脑组织恢复情况。结果术后2个月时在移植物周边见到GFAP阳性细胞形成的瘢痕层、CD68阳性细胞和NF阳性轴突;4个月时移植物周边的瘢痕层明显变薄,移植物内可见星形胶质细胞和NF阳性轴突;6个月时移植物内见到大量GFAP和CD68阳性细胞及再生的NF阳性轴突长度增加。结论含bFGF和bDNF的壳聚糖可以诱导胶质细胞向载体内迁移,并可促进轴突再生。

Objective To investigate the role of hydrogel made from chitosan, basic fibroblast growth factor(bFGF) and brain-derived neurotrophic factor(bDNF) in inducing cellular migration and promoting axonal regeneration of cerebral cortical injury region after transplantation. Methods The rat was placed in a stereotactic apparatus and the cerebral cortex 2mm×2mm×1.5mm was removed. Chitosan containing bFGF and bDNF was implanted into the brain cortical lesion site immediately.Two ,four and six months after hydrogel implantation into the lesioned cerebral cortex, HE stain and immunohistochemistry were used to assay brain tissue reparing. Results Two month after transplantation , a large number of astrocytes were found and astrocytes formed a scar tissue around the chitosan hydrogel.Meanwhile,CD_~68 + cells were found in and out of implantation,and NF+axons found around implantation.Four and six month later, there appeared a increase in density of astrocyte around chitosan hydrogel, and an increase of NF+axonal regeneration significantly. Conclusion Chitosan hydrogel containing bFGF and bDNF could induce gliocyte to migrate into gel itself, and promote axonal regeneration.