CD22 and neoplasm: Consistent with previous findings [9], CD19/CD22 BS Loop CAR-T cells not only demonstrated significantly enhanced cytotoxicity against CD19/CD22 double-positive tumor cell lines, surpassing that of the similar loop-structured CD19/CD22 dual-target CAR-T cells (CD19-22.BB.z-CAR) (Supplementary Fig. S1A and B), which was reported by a Stanford University group [19] but, more importantly, also exhibited significantly improved binding activity to the CD22 targets.