Cop-1诱导的自体免疫反应对慢性高眼压大鼠视网膜神经节细胞的保护作用

A neuroprotective autoimmunization model induced by COP-1 in a rat with chronically elevated intraocular pressure

目的建立慢性高眼压大鼠Cop-1免疫模型,从形态学上观察Cop-1诱导的自体免疫对视网膜神经节细胞的影响。方法将动物分为正常组、高眼压组及高眼压免疫组。用巩膜浅层静脉烧烙法建立大鼠慢性高眼压模型。高眼压免疫组在建立高眼压模型后即刻于大鼠后肢皮下注射200μg Cop-1,2周及4周后重复注射200μg Cop-1。8周后,从心脏取血,离心取上清液,用ELISA检测Cop-1抗体效价。组织切片行常规HE染色,光镜下对节细胞层细胞数进行计数。以TUNEL染色检测视网膜神经节细胞凋亡。结果Cop-1免疫大鼠后8周,血清中Cop-1抗体呈阳性,效价高于1∶1000。正常组视网膜神经节细胞计数平均为(22.5±1.18)个,高眼压组视网膜神经节细胞计数平均为(15.5±0.85)个,高眼压免疫组为(20.5±1.43)个。统计学分析显示,高眼压免疫组及正常组视网膜神经节细胞数明显高于高眼压组(P<0.01),而正常组与高眼压免疫组之间视网膜神经节细胞数没有明显差异(P>0.05)。TUNEL染色显示高眼压组视网膜神经节细胞凋亡数明显高于另外两组。结论Cop-1诱导的自体免疫反应可以对高眼压状态下的视网膜神经节细胞起到保护作用,减少视网膜神经节细胞的凋亡。

ObJective To establish Cop-1-immunized models in rats with chronic ocular hypertenasion, to investigate the morphological changes that occur in all layers of the retina in glaucomatous rats, and to assess the role of autoimmunization induced by Cop-1 in protecting the glaucomatous rat＇s retina against ocular hyperion. Methods Female Sprague Dawley rats were divided into 3 groups： normal group, glaucomatous group, and Cop-1-immunized group. After 2 episcleral veins were. cauterized, the animals were inmmunized with 200μg of Cop- 1 emulsified with an equal volume of complete. Freund＇s adjuvant （CFA）. The emulsion was injected into the hind legs of the rats. The animals were immunized again with the above antigen emulsified with an equal volume of incomplete Freund＇s adjuvant as a booster, 2 wk and 4wk after the first immunization. Eight weeks after the first treatment, the specific antibodies of Cop-1 were detected by Enzyme-Linked Immunosorbent Assay （ELISA）. Eye sections wexe stained with hematoxylin and eosin. TUNEL staining was done to detect apoptotic cells in the rat retinas. Results Eight weeks after autoimmunization induced by Cop-1, the specific antibodies of Cop-1 were identified in blood serums of Cop-1-immunized glaucomatous rats. Staining with hematoxylin and eosin .showed that the. glaucomatous retina was significantly thinner than the. normal retina （ P 〈 0.01 ）. There was a much higher presence, of TUNEL-positive ceils in the glaucomatous retina than in the normal retina. There was a reduced number of TUNEL-positive calls in the Cop-1-immunized glaucomatous retina. Conclusion Immunization with Cop-1 into the. hind legs of rats can effectively establish Cop-1-immunized models in the. rat. Ocular hypertension can harm layers of the retina. It can insult not only retinal ganglion cells but other nonneuronal cells as well. Cop- 1-induced autoimmunization can protect glaucomatous retinas against ocular hypertension and prevent retinal ganglion cells from apoptosis.