化学去细胞神经同种异系(体)移植的免疫学反应

Immunological study of chemically acellular nerve isografts in the rat

目的:观察化学去细胞神经同种异系(体)移植的免疫学反应,研究化学萃取去细胞处理对同种异系(体)神经抗原性的影响。方法:在W istar大鼠的背部和腹部皮下植入取自SD大鼠的化学去细胞神经,对照组植入新鲜同种异系(体)神经。用ELISA法测定大鼠血清内的抗体滴度。免疫组化染色检测各时间点异系(体)神经及周围组织中T淋巴细胞的浸润程度。结果:实验组和对照组2周、4周、8周、12周的大鼠血清均没有呈现阳性的抗体滴度。化学去细胞同种异系(体)神经移植组植入后2和4周时CD3+、CD4+和CD8+T淋巴细胞的浸润程度明显轻于未去除细胞的新鲜同种异系(体)神经移植组。8和12周时埋入的新鲜同种异系(体)神经已经被受体吸收,而去细胞同种异系(体)神经移植组的植入组织保持原形态,周围仅见极少量淋巴细胞浸润。结论:化学萃取去细胞同种异系(体)神经的抗原性明显降低,植入体内后免疫排斥反应不明显。

Objective：To observe the rejection response of acellular peripheral nerve isografts,and study the impact of chemical extraction on the immunogenicity of nerve isograft. Methods： Both sciatic nerves of twelve Sprague-Dawley rats were resected and made acellular by chemical extraction. Acellular isogeneic nerves and fresh isogeneic nerves from Sprague-Dawley rats were implanted into the dorsal and ventral subcutis of Wistar rats in experimental group and control group respectively. Serum antibody specific to isograft nerve antigen was assessed using enzyme-linked immunosorbent assay （ELISA）. T lymphocytes infiltration in isograft nerve was investigated by immunohistochemical methods, staining CD3, CIM and CD8 positive T lymphocytes with anti-CD3, CD4 and CD8 monoclonal antibodies （MoAb）. Results：There was no positive serum antibody avidity in two groups. Immunohistochemical stainings showed that the number of CD3, CD4 and CD8 positive T lymphocytes infiltrated into the nerve implants of the experimental group is much lower than that in the contrel group. The implanted fresh nerve isografts were absorbed 8w after implantation in the control group, but the acellular nerves could be preserved 12w after implantation in the experimental group.Conclusion ：The acellular nerve treated by chemical methods had much lower immunogenicity than fresh nerve, and there was no significant rejection response after iso-transplantation in the rat.