Interferon effects on multiplication, cytoplasmic protein and GFAP content, and morphology in human glioma cells.

Beta-type human fibroblast interferon inhibited the multiplication of human glioma cells in a dose-dependent manner. The inhibitory effects were thought to be due to suppression of the cells entering the S-phase. After interferon treatment with 5 \sX 103 IU/ml for ten days, the mean cell volume, the soluble protein, and the glial fibrillary acidic protein increased to 970%, 190%, and 380% that of the controls, respectively. The interferon-treated cells changed shape and resembled mature astrocytes. It is presumed that beta-type human fibroblast interferon inhibits DNA synthesis of cultured glial cells and subsequently induces specific differentiated proteins and morphologic alteration.