CD4 and neoplasm: Immune profiling revealed that tumor-infiltrating, but not splenic, CD4+Foxp3−Teff, CD8+ T-cells and NK cells expressed markedly higher levels of effector molecules, including IFNɣ, TNFα and Granzyme B (GzmB), in Prdm1fl/flFoxp3YFP-Cre mice compared to WT mice, despite that the total frequency of these cells in the tumor was not significantly changed (Fig. 2e and Additional file 6a-c).