BTLA and glioblastoma: The most frequent immune targets in the CD8+ T cells from the tumor microenvironment, in descending order, of newly diagnosed patients with GBM were A2aR > PD-1 > CD39 > TIGIT > LAG-3 > CTLA- 4 > BTLA > CD160 > CD73 > KIR > TIM3 (Figure 2A).