The tumor expresses human vimentin (hVim) and induces reactive gliosis in the adjacent brain parenchyma. GBM95 cells were injected in the striatum of immunecompetent mice 14 days before the immunohistochemical analysis. hVim staining (orange) at the core of the tumor mass (A), depicted by cell nuclei atypia (DAPI counterstaining in cyan, inset) and at the border of the tumor mass (B, delimited by dashed line, inset, and arrowheads) attest human origin of the tumor. (C–D) GFAP immunoreactivity cells in the contralateral hemisphere exhibit a stellate morphology. (E–F) In contrast, in the injected hemisphere, GFAP+ cells display a palisade arrangement of cell processes, which irradiate from the core of the tumor mass (delimited by the dashed line and indicated by the asterisk). Data represent four separate experiments. Scale bar, 40 μm. cc = corpus callosum; lv = lateral ventricle; Str = striatum.