A non randomized study ,plans to enrollment 24 subjects of acute B lymphocytic leukemia .The subjects will divide into low, medium and high dose groups，to evaluate the safety and tolerability of CD19-CD22 CAR - T cells，to evaluate the preliminary efficacy and observe PK/PD parameters of CD19-CD22 CAR -T cells immunotherapy in patients with relapsed or refractory acute B lymphocytic leukemia .
Evaluation the safety,tolerability, preliminary efficacy,and PK/PD of CD19-CD22 CAR-T cells for the treatment of acute B lymphocytic leukemia.