PD-1-MM@PLGA/RAPA NPs could permeate the BBB and subsequently accumulate in the glioblastoma microenvironment (Figure 10B,C) via macrophage chemoattractants secreted from glioblastoma cells, and further block the PD-1/PD-L1 axis (Figure 10D,E) [132]. This evidence concerns the gene PDCD1 and glioblastoma.