[Immunohistochemical study on Rosenthal fibers in gliomas using anti-GFAP and anti-ubiquitin antibodies].

: Immunohistochemically we investigated Rosenthal fibers (RFs) on specimen surgically removed from patients with glioma (three cerebellar astrocytomas, three optic gliomas, two spinal cord astrocytomas, one spinal ganglioglioma). Pathological diagnoses were pilocytic astrocytoma, fibrillary astrocytoma, and ganglioglioma. We utilized sections from the formalin-fixed paraffin-embedded tissues and stained them with H & E, PTAH, PAS as well as with anti-GFAP (glial fibrillary acidic protein) antibody (Ab) and two anti-ubiquitin Abs...anti-PHF (paired helical filament) monoclonal Ab (DF2) which recognizes ubiquitin (H. Mori in Science) and anti-ubiquitin polyclonal Ab provided by Dr. Haas. The primary antibodies were diluted with Tris-saline as follows: anti-GFAP (1:500), DF2 (culture medium without dilution), anti-ubiquitin (2 micrograms/ml). Sections were deparaffinized and incubated with primary antibodies overnight at room temperature. They were visualized by the avidin-biotin-peroxidase complex (ABC) procedure (Vectastain, Vector, USA) and counterstained with hematoxylin. Negative control sections were treated by omitting the primary antibodies. In the representative specimen we compared H & E, anti-GFAP and anti-ubiquitin staining on 3 microcrons serial sections. RFs were eosinophilic (bright red on H & E), purply-stained with PTAH (metachromasia), black with Heidemhein's iron-hematoxylin, and negative with PAS. Anti-GFAP Ab stained glial filaments diffusely in the cytoplasm and cell process of astrocytomas in every case. The peripheral parts of most RFs were intensely stained with anti-GFAP. The whole part of some RFs showed dark staining, and no part of a few RFs showed positive reactivity.(ABSTRACT TRUNCATED AT 250 WORDS)