CD4 and neoplasm: Moreover, depletion of Treg cells was associated with functional maturation of CD8 and CD4 T cells, as demonstrated by increased interferon γ-producing cells (Fig. 7f) and tumor necrosis factor α-producing T cells within tumor microenvironment (Supplementary information, Figure S7A and B) but not in the spleen (Supplementary information, Figure S7C-F).