CD19-CAR-T Cells in Patients With R/R B-ALL

Inclusion Criteria: 1. Obtain Informed Consent Form (ICF) voluntarily signed by the patient; 2. Age 3-70 years old; 3. Primary resistant or relapsed B-cell line acute lymphoblastic leukemia; 4. B cells are positive for CD19 expression; 5. Peripheral blood tumor cell load \<50%; 6. KPS score \>50 points; 7\. Normal liver and kidney function; 8. Normal heart function; 9. Good follow-up compliance; 10. Women of childbearing age (15-49 years old) must have a pregnancy test within 7 days before treatment and have a negative result; Men and women with fertility should agree to use effective contraception to ensure that during the study period and following 3 months after treatment the women will not get pregnant. Exclusion Criteria: 1. Patients with non-B cell acute leukemia; 2. Organ failure: Heart: Grade III and IV Liver: Class C with Child-Turcotte liver function classification Kidney: Renal failure and uremia Lung: severe respiratory failure Brain: Disabilities 3. Active infection; 4. Human immunodeficiency virus (HIV) positive; 5. Acute and chronic graft-versus-host disease (GVHD)\> Level 1； 6. Pregnant or lactating women; 7. Patients do not agree to use effective contraception during the treatment period and following 3 months; 8. Patients who participated in other clinical studies at the same time; 9. The researcher believes that there are other factors that are not suitable for inclusion in or influence the subject's participation in or completion of the study; 10. Long-term use greater doses of hormones than physiological doses.