CD4 and neoplasm: Furthermore, the fraction of effector memory T cells (CD4+CD44highCD62Llow and CD8+CD44highCD62Llow) was significantly increased in the combination treatment group compared with the untreated group (P < 0.001) in the peripheral blood (Fig 6B and C, and Appendix Fig S25), demonstrating that combination treatment with RBC‐Nanovaccines and anti‐PD‐1 antibody could elicit a long‐lasting memory immune response to prevent tumor recurrence.