PDCD1 and glioblastoma: To screen GBM subtype-specific responses, we delivered monotherapy or dual-therapy regimens of brain-penetrant CSF-1R inhibitor (BLZ945, 0.1 μg/ml) to ablate TAM immunosuppressive function and human IgG4 anti-PD-1 monoclonal antibody (nivolumab, 1 μg/ml) to inhibit the PD-1/PD-L1 pathway every 24 hr for 3 days.