These studies have shown abundant myeloid cells in the TIME of GBM as well as brain metastases of melanomas or carcinomas,9 10 17 33 34 and that primary brain tumors such as glioma are especially enriched in myeloid cells and poor in DCs.9 10 Our data agree with a recent study showing that immunosuppressive macrophages (PD-L1+ CD73+) are enriched in patients with GBM.17 Immune profiling studies from Lathia and colleagues have focused on myeloid-derived suppressor cells (MDSCs) as a dynamic cell population both in the GBM patients’ blood and the TIME. Here, CD274 is linked to melanoma.