Neoantigens can induce both CD4 and CD8 T-cell responses, and reactivity of one or both T-cell subsets against mutated tumor peptides was confirmed initially by testing tumor-infiltrating T-cell (TIL) products expanded from melanoma [174,175,176], epithelial cancer [177], cervical cancer [178] and colorectal cancer biopsies [179,180]. The gene discussed is CD4; the disease is melanoma.