Following the same ACT strategy as demonstrated above (Fig. 8 A), we observed that 4G-CAR-T cells in the spleen (Fig. 8, B and C) and tumor-draining lymph nodes (Fig. S5, A and B) exhibited a higher frequency of Ki67 (cellular marker for proliferation) than 2G-CAR-T cells. Here, MKI67 is linked to neoplasm.