Cytoplasmic intermediate filaments in cultured glial cells.

Monolayer cultures of rat glial cells derived from 12 to 14 day fetal spinal cords and rat C6 glioma cells were examined for immunofluorescent reactivity with human or rabbit autoantibodies to intermediate filaments and with rabbit antibody to GFAP. The embryonic glial cells and C6 glima cells reacted identically with both. Protoplasmic astrocytes gave immunofluorescent staining of an intricate network of cytoplasmic filaments while fibrous astrocytes and C6 glioma cells gave diffuse cytoplasmic staining of the cell body and cell processes. Cells, pretreated with colchicine or vinblastine, showed staining of thick coils of peri-nuclear, circum-nuclear, or juxtanuclear filaments. The observations suggest that intermediate filaments in glial cells contain unique antigenic determinants as well as antigenic determinants shared with intermediate filaments in other cell types,