实验性自身免疫性葡萄膜视网膜炎中T-bet的表达及意义

Expression and significance of T-bet in experimental autoimmune uveoretinitis

目的 研究实验性自身免疫性葡萄膜视网膜炎 (EAU )中 T- bet的表达及意义。 方法 L ewis大鼠 2 8只 ,用视网膜 S抗原与 Freund完全佐剂免疫 2 4只大鼠以诱导 EAU模型 ,另外 4只作为正常对照。免疫组大鼠分别于免疫后 7、12、15、2 1d被处死 ,取所有大鼠的眼球和脾脏 ,固定后制作眼组织平片和眼球及脾脏的石蜡连续切片。使用单克隆抗 T- bet和 CD4的抗体 ,通过免疫组织化学细菌蛋白过氧化物酶法在上述组织平片及切片上进行免疫组织化学单染和双染色 ,在光学显微镜下观察并计数阳性细胞 ,数据经 SPSS11.0统计学软件分析。 结果 正常眼和脾组织中均见少量 T- bet阳性细胞 ;免疫后 7d,虹膜、视网膜及脾脏中 T- bet的表达增加 ,免疫后 15 d达高峰 ,免疫后 2 1d表达降低 ,但仍高于正常组。免疫组织化学双染色显示 ,T- bet阳性细胞中多数为 CD4 + 。 结论 T- bet在 EAU的发病中起着重要作用 ,其作用可能是通过激活辅助性 T淋巴细胞 1而实现的。

Objective To investigate the expression and significance of T-bet in experimental autoimmune uveoretinitis (EAU). Methods EAU was induced in 24 Lewis rats by immunization with retinal S-antigen (50 μg) and complete Freund′s adjuvant, and another 4 rats were the healthy control. The rats with EAU were executed 7, 12, 15, 21 days after immunization, respectively. Immunohistochemical single and double staining were performed using monoclonal antibodies of T-bet or CD4 on the ocular wholemounts and the consecutive sections of the eye and spleen from both 24 immunized Lewis rats and 4 normal controls. The positive cells were counted under the optic microscope and the data were analyzed by SPSS 11.0 statistic software. Results A few T-bet positive cells were observed in the normal ocular tissues and spleen. The expressions of T-bet in the iris, retina, and spleen increased 7 days after immunization, reached the peak at the 15th day, and decreased at the 21st day, which were higher than those in the control. Double staining on the consecutive sections revealed that most of the T-bet positive cells were positive for CD4 monoclonal antibody. Conclusion T-bet may affect the occurrence of EAU by activating Th1 cells.