灵长类去细胞神经的萃取制备及异体移植后早期神经再生观察

Early regeneration of monkey nerve after acellular allografting made by chemical extraction

目的发展新的化学处理方法,清除灵长类周围神经中的细胞和髓鞘,降低其抗原性,萃取粗大和长段的去细胞神经移植物,并观察其同种异体移植的早期神经再生。方法以TritonX-100和脱氧胆酸钠溶液化学处理猴长段正中神经和坐骨神经。萃取的去细胞神经行普通组织学染色、免疫组化染色及透射电镜检查,观察其组织结构。以去细胞神经同种异体移植修复猴正中神经3.0cm和胫神经5.0cm缺损,术后3周和8周,通过大体观察、HE染色及免疫组化染色观察早期神经再生。结果细胞和髓鞘已被彻底清除,神经基底膜和雪旺细胞基底板层保留完好,去细胞神经成为空的神经基质管。移植术后8周轴突再生已通过远端吻合口,移植段再血管化及雪旺细胞增殖良好。结论该化学处理可萃取灵长类粗大和长段的去细胞神经,作为同种神经移植物不会被排斥吸收。

Objective To develop a chemical extraction method by which Schwann cells and myelin in peripheral nerve can be removed while the basal lamina tubes remain intact, and to obtain a thick and long acellular nerve allograft in monkeys. Methods 8 median nerves and sciatic nerves 10.0 cm long were excised from 2 monkeys and were treated with a solution of Triton X 100 and a solution of sodium deoxycholate. The structure of acellular nerve was observed by ordinary histological and immunohistochemical staining and by a transmission electron microscope. The models of defects of median nerves (3.0 cm in length) and tibial nerves (5.0 cm in length) were set up and the defects were bridged by the acellular nerve allografts in two monkeys. The histological observation for the early nerve regeneration was carried out at 3 and 8 weeks postoperatively. Results Cells, axons and myelin sheath were removed in the acellular nerve. Basal membrane and Schwann cell basal lamina component were preserved and empty basal lamina tubes remained in the endoneurium after chemical treatment. There was a mass of regenerating nerve, vessel and Schwann cells in the grafting nerve at 8 weeks postoperatively. Conclusions The thick and long acellular nerve allografts of monkeys can be obtained by the chemical extraction method. They will not be rejected or absorbed by the host after repair of a long nerve defect.