Response to CAR T-cell therapy. (A) The flowchart of the trial. (B) Time course of 2 cycles of CAR T-cell therapy in 20 individuals. (C) The rate of MRD⁻ CR in all patients, those with hematological relapse, and those with refractory FCM-MRD⁺ disease. The total number of patients and those in the different groups are indicated in brackets. (D) Leukemia lesions in a patient before and after CAR-T-cell therapy, detected by whole-body position-emission tomography (PET)/computed tomography (CT). (E) CAR T-cell expansion in PB of 20 patients after CD19 (E) and CD22 (F) CAR T-cell infusion.