CD4 and neoplasm: Engineering DCs to produce IL-12, either alone or in combination with IL-18, represents a novel approach to enhancing the efficacy of DC-based vaccines, as investigated by Mierzejewska et al. According to their study, the application of DCs engineered to produce IL-12 alone or in combination with IL-18 can enhance the filtration and activity of CD4+ and CD8+ T lymphocytes in the TME and tumor-draining lymph nodes [199].