摘要目的 探讨辅助性T细胞(Th细胞)在多聚物-1( Cop-1)对高眼压大鼠视网膜神经节细胞保护中可能发挥的作用.方法 Wistar大鼠分别结扎3根巩膜上静脉,建立高眼压模型96只,完全随机法分入Cop-1免疫组48只,磷酸盐缓冲液(PBS)免疫组48只,另10只正常大鼠作对照.于免疫后3、7、10、17、24、31 d,用免疫荧光染色法观察视网膜切片中Th1、Th2数量变化,并通过免疫蛋白印迹法检测不同组别大鼠视网膜中IL-4蛋白的变化.结果 免疫荧光显示,免疫后7d,Cop-1组与PBS组视网膜上Th1数量增多,分别为(216±21 )/mm2与(194±27 )/mm2,此后两组Th1数量随时间延长而减少,在各个时间点均差异无统计学意义;免疫后7d,Cop-1组视网膜上Th2数量远大于PBS组,差异有统计学意义[(300±28)/mm2和( 129±27)/mm2,P＜O.01],随后Cop-1组的rh2数量随时间延长而减少,仍大于PBS组.蛋白印迹表明,免疫后3d,Cop-1组视网膜上IL-4相对蛋白含量已高于PBS组;7 d,Cop-1组IL-4含量为2.11±0.06,高于PBS组0.57±0.05,随后,每个时间点Cop-1组的IL-4含量均高于PBS组(均P＜0.05).结论 Cop-1引起高眼压大鼠视网膜中Th2型细胞因子IL-4聚集,提示Cop-1对视网膜神经节细胞保护可能是通过特异性Th2细胞发挥效应.

abstractsObjective To explore the morphological and expressional changes of Th1 cells and Th2 cells in retina of a rat model of glaucoma vaccinated by Cop-1 ( Copolymer-1 ) and elucidate the possible neuroprotection roles played by Th1/Th2.Methods After modeling,the aqueous outflow from the right eyes was blocked by a ligation of three of four episcleral veins.There were 48 rats with elevated IOP ( intraocular pressure) immunized by Cop-1 ( Cop-1 group),48 rats with elevated IOP immunized by PBS ( phosphate buffered saline) (PBS group) and 10 rats without any treatment (normal group).The experimental rats were immunized with Cop-1/PBS emulsified in a total volume of 0.4 ml complete Freund's adjuvant.The immunization was administered subcutaneously at the base of tail.Immunofluorescence was employed to test the distribution and activation of Thl and Th2 cells in retina at Days 3,7,10,17,24 and 31 post immunization respectively for each group.Western blot was selectively performed according to the results of immunofluorescence to verify if there was a similar variation of the retinal expression of IL-4 protein.Results The results of immunofluorescence showed the numbers of Thl cells peaked at Day 7 in both Cop-1 ( (216 ± 21 )/mm2) and PBS groups (( 194 ±27 )/mm2 ).And no statistical significance existed between two groups (P＞0.05).The numbers of Th2 cells in the experimental groups peaked at Day 7 with statistical significance ( Cop-1 group:300 ± 28/mm2 vs PBS group:129 ± 27/mm2 ) ( P ＜ 0.01 ).With the prolongation of experimental period,the number of Th2 cells decreased gradually in the Cop-1 group but remained greater than that of the PBS group afterward ( P ＜ 0.05 ).The Western blot results showed that the expression of IL-4 in the Cop-1 group ( 1.91 ± 0.05 ) was significantly higher than that of the PBS group (0.51 ±0.04) from Day 3 and peaked at Day 7 (2.11 ±0.06 vs 0.57 ±0.05).Then the IL-4 expression decreased gradually in the COP-1 group but still represented statistical significance versus the PBS group until Day 31 post-immunization ( P ＜0.001 ).Conclusion The retinal activation and accumulation of IL-4 are found in a rat model of chronic glaucoma immunized by Cop-1.Thus Th2 cells may play vital roles in the Cop-l-induced neuroprotective autoimmune responses.