Geiger D H, Rossouw D J, Hewlett R H, Rutherfoord G S
Department of Anatomical Pathology, Faculty of Medicine, University of Stellenbosch and Tygerberg Hospital, South Africa.
Biotech Histochem. 1995 Nov;70(6):285-93. doi: 10.3109/10520299509108334.
Standardized postembedding immunoelectron microscopy was performed to demonstrate glial fibrillary acidic protein (GFAP) and vimentin in individual intermediate filaments to determine the diagnostic value of demonstrating ultrastructural and immunophenotypic characteristics of intermediate filaments in routine brain biopsy specimens. Dual expression of GFAP and vimentin was observed in the astroblastoma and astrocytes of Alexander's disease. The antigen availability for vimentin, however, was too low to allow reliable assessment of the GFAP:vimentin ratio in individual intermediate filaments and/or filament bundles. In meningioma, only vimentin positive intermediate filaments were found. GFAP positive intermediate filaments were present in all other specimens except the oligodendroglial components of the mixed glioma, which were devoid of intermediate filaments. GFAP positivity in the filamentous periphery and electron-dense core of Rosenthal fibers was demonstrated. Technical and tissue processing factors had a significant effect on particle density values obtained for individual specimens. Although the number, distribution, and density of glial intermediate filaments varies in different astroglial entities, correlation of particle density values determined by immunoelectron microscopy with relative GFAP concentrations in different lesions requires utmost caution. Nevertheless, application of the postembedding approach to routinely fixed biopsy specimens indicated an association of different entities with the exclusive presence of GFAP and/or vimentin in individual intermediate filaments, thus emphasizing the diagnostic value of intermediate filament typing for pathological characterization.
采用标准化的包埋后免疫电子显微镜技术，在单个中间丝中显示胶质纤维酸性蛋白（GFAP）和波形蛋白，以确定在常规脑活检标本中显示中间丝的超微结构和免疫表型特征的诊断价值。在亚历山大病的成星形细胞瘤和星形胶质细胞中观察到GFAP和波形蛋白的双重表达。然而，波形蛋白的抗原活性过低，无法可靠地评估单个中间丝和/或丝束中GFAP:波形蛋白的比例。在脑膜瘤中，仅发现波形蛋白阳性的中间丝。除混合胶质瘤的少突胶质细胞成分（无中间丝）外，所有其他标本中均存在GFAP阳性的中间丝。证实了罗森塔尔纤维丝状周边和电子致密核心中的GFAP阳性。技术和组织处理因素对各个标本获得的颗粒密度值有显著影响。虽然不同星形胶质细胞实体中胶质中间丝的数量、分布和密度各不相同，但免疫电子显微镜测定的颗粒密度值与不同病变中相对GFAP浓度的相关性需要极其谨慎。尽管如此，将包埋后方法应用于常规固定的活检标本表明，不同实体与单个中间丝中GFAP和/或波形蛋白的单独存在有关，从而强调了中间丝分型对病理特征诊断的价值。
