SUBRETNAL TRANSPLANTION OF HUMAN AMNIOTIC MEMBRANE IN RABBITS

黄斑下手术去除年龄相关性黄斑变性患者的脉络膜新生血管可以改善或稳定特定患者的视力。然而，视网膜色素上皮经常受损，导致视力不佳。人羊膜是厚的基底膜，具有抗粘附性能，促进上皮化，减少炎症、新生血管和纤维化。据报道，羊膜移植在眼表重建中是有效的。我们用兔模型研究了人羊膜植入视网膜下后视网膜色素上皮的重建。采用标准视网膜下手术及器械完成羊膜植入。每周检查，植入后1 ~ 4周处死家兔进行CD4和CD8的组织学和免疫组织学研究。未见炎症、纤维蛋白、视网膜水肿、视网膜脱离。视网膜重新附着在羊膜上。组织学检查显示羊膜下PE增生2周。然而，在裸露的布鲁氏膜上未观察到PE增生。CD4和CD8阳性细胞在第2周出现，但在第4周出现下降。兔视网膜下人羊膜的耐受性表明，羊膜和视网膜下空间都是免疫特权部位。在黄斑下手术中，羊膜可作为有用的替代膜。

Submacular surgery for the removal of choroidal neovasucularization in age related macular degeneration can improve or sstabilize vision in selected partients. However, the retinal pigment epithelium are frequently damaged and contribute to the poor visual outcome. Human amniotic membrane is thick basement membrane and has anti-adhesive properties and promote epithelialization and decrease inflammation, neovasucularization, and fibrosis. Amniotic membrane transplantation has been reported to be effective in the reconstruction of the ocular surface. Using rabbit model, we have investigated the reconstruction of retinal pigment epithelium following subretinal implantation of human amniotic membrane. The implantation of amniotic membrane was achieved using standard subretinal surgery and instrument. Weekly examination was performed and 1 to 4 weeks after implantation, rabbits were sacrificed for histological and immune histological study of CD4 and CD8. No evidence of inflammation, fibrin, retinal edema, retinal detachment was detected. The retina reattached over the amniotic membrane. Histological cvaluation revealed PE proliferation under the amniotic membrane in 2 weeks. However, PE proliferation did not observed over bare Bruch's membrane. The CD4 and CD8 positive cells were observed in 2 weeks, but decreased in 4 weeks. The tolerance of subretinal human amniotic membrane in rabbits showed both amniotic membrane and subretinal space are immune-privileged site. The amniotic membrane may serve as a useful replacement during submacular surgery.