Vinores S A, Van Niel E, Kim H J, Campochiaro P A
Department of Ophthalmology and Neuroscience, Johns Hopkins University/Hospital, Baltimore, Maryland.
Invest Ophthalmol Vis Sci. 1992 Nov;33(12):3361-6.
The identification of cells comprising epiretinal membranes is difficult because of the phenotypic changes that occur. Examination of intermediate filament protein content by immunocytochemical analysis can help to identify some cells with altered ultrastructure but is not always definitive because altered expression of intermediate filament proteins can also occur. To examine this issue further, the authors utilized a postembedding immunocytochemical technique with epiretinal membranes in which they were able to double label for keratin, a useful marker for identifying retinal pigment epithelial cells, and glial fibrillary acidic protein (GFAP), a useful marker for identifying glial cells. Nine of ten idiopathic epiretinal membranes contained cells that labeled for GFAP and not keratin. Two of these membranes also contained cells that labeled only for keratin and one membrane contained cells that simultaneously labeled for both GFAP and keratin. Other types of epiretinal membranes had an equal participation by cells that expressed only GFAP or keratin (12 of 17 membranes contained cells positive for keratin; 13 of 17 contained cells positive for GFAP). Ten of 17 nonidiopathic membranes contained cells simultaneously expressing GFAP and keratin, although they comprised only a minor subpopulation of the total number of cells present. These findings demonstrate that keratin and GFAP are not mutually exclusive intermediate filament proteins in cells of epiretinal membranes and that, although each may provide a helpful adjunct for cell type identification, neither is an absolutely specific marker.
由于发生的表型变化，识别构成视网膜前膜的细胞很困难。通过免疫细胞化学分析检测中间丝蛋白含量有助于识别一些超微结构改变的细胞，但并不总是确定的，因为中间丝蛋白的表达改变也可能发生。为了进一步研究这个问题，作者利用一种视网膜前膜包埋后免疫细胞化学技术，在此技术中他们能够对角蛋白（一种用于识别视网膜色素上皮细胞的有用标志物）和胶质纤维酸性蛋白（GFAP，一种用于识别神经胶质细胞的有用标志物）进行双重标记。十例特发性视网膜前膜中有九例含有标记GFAP而不标记角蛋白的细胞。其中两例视网膜前膜还含有仅标记角蛋白的细胞，一例视网膜前膜含有同时标记GFAP和角蛋白的细胞。其他类型的视网膜前膜中，仅表达GFAP或角蛋白的细胞参与程度相同（17例视网膜前膜中有12例含有角蛋白阳性细胞；17例中有13例含有GFAP阳性细胞）。17例非特发性视网膜前膜中有10例含有同时表达GFAP和角蛋白的细胞，尽管它们仅占总细胞数的一小部分。这些发现表明，角蛋白和GFAP在视网膜前膜细胞中并非相互排斥的中间丝蛋白，而且，尽管每种蛋白都可能为细胞类型识别提供有用的辅助手段，但都不是绝对特异性的标志物。
