CD4 and neoplasm: The neoantigen vaccines based on the immunogenic mutations induced by radiotherapy elicit CD8+ and CD4+ T cells that improved the therapeutic efficacy of radiotherapy.476 Notably, highly subclonal neoantigens induced by radiation, which might be worsened by DNA-damage response (DDR) inhibitors, would interfere with the production of T lymphocytes against clonal tumor neoantigens.