Safety and Efficacy Study of CD22 CAR-T Cells for Relapsed or Refractory Acute Lymphoblastic Leukemia

Inclusion Criteria: 1. Patients with relapsed and refractory acute B-lymphoblastic leukemia who have any of the following: 1. B-ALL patients with relapse (including bone marrow morphological relapse 1 and minimal residual relapse 2) after remission by chemotherapy or autologous stem cell transplantation; 2. Primary B-ALL patients who can not be completely relieved by more than two times of repeated chemotherapy; 3. High risk primary B-ALL patients who have not been relieved but are not suitable for re intensive therapy after 1-2 times of chemotherapy; 2. Flow cytometry (FCM) showed CD 22 positive in bone marrow or peripheral blood; 3. There should be at least one assessable lesion in B-ALL patients with simple extramedullary recurrence; 4. The activity state score of the Eastern Cooperative Oncology Group (ECOG) was less than or equal to 2; 5. The estimated survival time is more than 3 months; 6. Need to sign informed consent. Exclusion Criteria: 1. Serious cardiac insufficiency； 2. Has a history of severe pulmonary function damaging; 3. Other malignant tumors; 4. Serious infection or persistent infection and can not be effectively controlled； 5. Merging severe autoimmune diseases or immunodeficiency disease; 6. Patients with active hepatitis (HBV DNA or HCV RNA positive); 7. Patients with HIV infection or syphilis infection; 8. Has a history of serious allergies on Biological products (including antibiotics); 9. Being pregnant and lactating or having pregnancy within 12 months; 10. Any situations that the researchers believe will increase the risks for the subject or affect the results of the study（including a history of serious mental illness, substance abuse and addiction）