Focusing on cytokine production by the four subsets identified by TIGIT and PD‐1 expression (Figure 3B–F), we observed a higher frequency of CD4+ T cells expressing the proinflammatory cytokines IFN‐γ, TNF‐α, and GM‐CSF in WL‐GBM samples compared with the corresponding PB populations with statistical significance for IFN‐γ and TNF‐α expression in the PD‐1+ TIGIT−, PD‐1+TIGIT+ and PD‐1−TIGIT− subpopulations (Figure 3B–D). Here, TNF is linked to glioblastoma.