CCL19 and neoplasm: As shown in Fig. 1B, the main mechanism of HCI fusion protein combined with immune cells against HER-2 positive tumor cells is relying on the CCL19 to recruit DC or T cells to migrate to the tumor site and IL-7 can enhance the proliferation and viability of effector cells, which had been approved by the previous studies in 7 × 19 CAR-T cell therapy.