CD4 and glioblastoma: Indeed, another study reported higher infiltrative CXCR3+ CD4+ (T effector memory and T regulatory) and CD8+ (T effector memory only) expression in tumor samples from GBM patients than in blood samples from the same patients, although it remains unclear whether CXCR3 ligands were responsible for the direct recruitment of CXCR3+ immune cells [45].