Figure 5.

GITRL and CTLA-4 blockage additively abolish (T)cell suppressive capacity of tumor-infiltrating Treg. Blood-derived CFSE-labeled CD4⁺CD25⁻ T cells from HCC-patients or LM-CRC patients were co-cultured with autologous CMV-DC for 5 d Autologous tumor derived Treg were added in a ratio 1:5. Cells were treated with 10 µg/mL of anti-CTLA-4 mAb or GITRL or a combination of both. Cell proliferation and cytokine production were analyzed by flow cytometry after re-stimulation with CMV-activated Mo-DC. (A) Depicts a representative experiment showing T cell proliferation, IFNγ and TNFα production after co-culture and re-stimulation. (B) Collective data of 5 patients tested (3 LM-CRC and 2 HCC) showing the relative T cell proliferation or cytokine production (IFNγ and TNFα) by proliferating cells. Values are means ± SEM, * p < 0.05, ** p < 0.01, *** p < 0.001. Comparison between groups was made by paired t-test.