PDCD1 and glioblastoma: To overcome the access barrier of the BBB in delivering CPI Abs to disrupt the PD1-PDL1 axis on CAR T cell function in orthotopic GBM, we further genetically modified the EGFRvIII CAR T cells to perform a second function, specifically to act as mini bio-factories, producing their own anti-PD1 Ab for CPI.