As shown in Fig. 6A-C, significantly enhanced infiltration of CD8-positive T cells and CAR-T cells of CD8-positive T cells (Fig. 6A and Fig. S10A-B) along with decreased percentages of MDSCs (Fig. 6B) and M2 TAMs (Fig. 6C) were found in the tumor tissues of CART-CEA.sBsAb-treated mice compared with those of other groups. Here, CEACAM5 is linked to neoplasm.