CD4 and neoplasm: Actually, the anti-PD-L1 treatment led to an increase in activated cytotoxic CD4+ T and CD8+ T cells in the TILs (IFNγ+CD4+ T cells and IFNγ+ CD8+ T cells) (Fig. 2i) and resulted in an increased number of TUNEL-positive cells in 4T1-WT tumours (Fig. 2j).