结缔组织生长因子在兔视网膜增生膜中的表达

Expression of connective tissue growth factor in retinal periretinal membrane in rabbit

目的观察结缔组织生长因子(CTGF)在实验性增生性玻璃体视网膜病变(PVR)增生膜中的表达,探讨CTGF在PVR视网膜增生膜形成过程中的作用。方法采用Nobuyo的方法从兔视网膜中分离视网膜色素上皮(RPE)细胞并进行体外培养和传代。第3代RPE细胞制备密度为1.1×105/mL的细胞悬液。32只日本大耳白兔,取8只作为正常对照组,其余24只采用玻璃体腔内注入RPE细胞悬液的方法建立PVR动物模型。动物分别于造模后7、30、60d处死并摘除眼球,每次处死8只动物。光学显微镜下观察视网膜增生膜的组织学改变,免疫组织化学法检测PVR视网膜增生膜中CTGF的表达。结果造模后5d检眼镜下可见视网膜增生组织开始形成,增生膜随时间的推移逐渐增厚。组织学检查显示,造模后7d兔视网膜表面可见红染的条索状和网状胶原纤维,并可见大量的增生细胞分布其中。光学显微镜下可见视网膜内界膜变厚、粗糙、断裂或结构不清,视网膜各层结构欠清。免疫组织化学法检测表明,正常对照组在玻璃体及视网膜内未见CTGF的特异性染色。造模后7d,CTGF主要表达于视网膜表面增生细胞;造模后30d,CTGF主要表达于增生的细胞及增生的胶原纤维组织中;造模后60d,CTGF主要表达于增生的胶原纤维组织中。结论 CTGF在实验性PVR动物模型中呈高表达,提示CTGF参与了PVR增生膜的形成。

Background Research demonstrated that the connective tissue growth factor （CTGF） and proliferative vitreoretinopathy （PVR） has a close relationship.To investigate the expression of CTGF in retinal periretinal membranes （PRM） has important significance for clinical and pathological study of PVR.Objective Present study was to investigate the expression of CTGF in retinal PRM of PVR of experimental animal model.Methods RPE cells were isolated from rabbits and cultured with Nobuyo method and the cell suspension was prepared with the cell density of 1.1×10^5/mL.PVR animal models were established by injecting cultured RPE cells into vitreous in 24 Japanese white rabbits.Eight normal Japanese white rabbits were used as controls.The animal were sacrificed on 7,30,60 days respectively and eyeballs were enucleated for pathological examination.Expression of CTGF in PRM was evaluated using immunohistochemistry.Results The experimental PVR gradually formed from 5 days through 60 days after injection of vitreous.The histologic examination showed the red-dyed streak,reticulate collagen fibers and a large number of proliferative cells on the retinal surface in the model eyes.Thickness and rupture of the internal limiting membrane,destroy of retinal structure also were seen under the optical microscope.No expression of CTGF was found in retina and vitreous of normal control group.However,CTGF was positively expressed in proliferative cells on the surface of PRM in the 7th day after establishment of model.In the 30th day after establishment of model,CTGF was mainly expressed in proliferative cells and collagen fibers of PRM,and majority of CTGF was positively expressed in proliferated collagen fibers of PRM on the 60th day after injection of vitreous.Conclusion CTGF is overexpressed in PRM of experimental PVR,indicating that CTGF takes part in the formation of PRM in PVR.