CD4 and neoplasm: The TG01 peptides are 17 amino acids long, and designed to activate both major histocompatibility complex MHC class II-restricted CD4 + helper T cells, as well as MHC class I-restricted CD8 + cytotoxic T cells, which are necessary to sustain the CD8 + cytotoxic T-cell effect.10–12 The activated CD4 + cells are also important for enhancing/facilitating cross-presentation of tumour neoantigens and tumour-associated antigens by dendritic cells (DC) at the site of the tumour, and thus broadening the cytotoxic CD8 + anticancer activity.