PDGFB and glioblastoma: In contrast to PDGFB-overexpressing tumors (resembling human PN GBM) or EGFRvIII-expressing tumors (resembling human CL GBM) where the majority of myeloid cells are of monocytic lineage, Nf1-silenced murine tumors (resembling human MES GBM) are enriched with neutrophils and brain-resident microglia4,16, similar to what was shown in human GBM17.