CD4 and glioblastoma: To explore the relationship between CD45, CD4, CD8, PD-1-presenting lymphocytes and GBM clinical prognostic features, we dichotomized the CD45+, CD4+, CD8+, PD-1+ TIL counts and the PD-1+/CD8+ ratio into high and low using either the median count or the median ratio as cutoff points, as appropriate.