AIF1 and astrocytoma (excluding glioblastoma): To determine whether the mesenchymal subtype contained a greater number of microglia/macrophages, we generated tissue microarrays from adult subtyped GBM (n = 24) and from UCSF pediatric subtyped astrocytomas (n = 13), and analyzed microglia/macrophage number, as determined by Iba1 immunohistochemistry.