For instance, CAR-T cells targeting the CD19 antigen on B cells have achieved complete remission rates of up to 85% in patients with acute lymphoblastic leukemia (ALL) and up to 100% in patients with refractory or relapsed B-cell acute lymphoblastic leukemia (r/r B- ALL) (9–11). Here, CD19 is linked to B-cell acute lymphoblastic leukemia.