CD4 and brain neoplasm: When CD4+ T cells were isolated from the GSC005 brain tumor at day 12 post-treatment and subjected to co-culture with irradiated splenocytes plus Trp-1 peptide for 80 hr, we observed the increased CD4+ T cells, including IL6ra+Bcl-6+ and Tcf-1+Bcl-6+ populations, and elevated expression of Bcl-6, Tcf-1 and GzmB in M002-treated cells compared to saline control cells, while these increases were all significantly reduced in the co-culture supplemented with anti-IL6ra blocking antibody (Fig. 6f–h and Supplementary Fig. 10f).