CD19 is, for instance, the target antigen of blinatumomab (Blincyto), a CD19-CD3 bispecific antibody, and of Tisagenlecleucel (CTL019), a CAR-T product, both approved by the FDA for the treatment of relapsed and refractory B cell acute lymphocytic leukaemia (B-ALL) by immunotherapy [9,10,11]. The gene discussed is CD19; the disease is acute lymphoblastic leukemia.