CD4 and neoplasm: CD4+ cells play a pivotal role in promoting CD8+ effector functions and in facilitating direct killing of tumour cells.20, 21 The combined actions of CD4+ cells and cytokines (INF-γ and TNF) induce tumour senescence.22 Thus, the presence of CD4+ T-cell responses in our study might be sufficient for an effective antitumour immune response mediated by the PRAME immunotherapeutic.