CD4 and glioblastoma: Comparing the mean fluorescence intensities (MFI) of several markers on different immune cell populations between patient and control groups we could confirm our data from the basic mFC cohort showing that HLA-DR levels were more abundant on T lymphocytes of glioblastoma and RRMS patients compared to HC and on CD8+ and CD4+ lymphocytes of glioblastoma patients in comparison to HC.