γδT Cell Infusion to Prevent Relapsed/Refractory Leukemia Rescue Relapse

Inclusion Criteria: * Acute leukemia patients undergoing salvage allogeneic hematopoietic stem cell transplantation * Age 10-65,Any gender * Expected lifetime\>3months * ECOG 0-2 * DSA Negative * Successful granulocyte implantation * Liver and kidney function, heart and lung function meet the following requirements:①Creatinine≤1.5 ULN；②ALT/AST ≤5 ULN； ③Baseline oxygen saturation≥92%； ④Left ventricular ejection fraction≥50% * Female subjects with fertility who had a negative pregnancy test within 48 hours before the infusion and were not breastfeeding; all subjects with fertility potential before enrolling in the study and throughout the study period until the last infusion Within 3 months, take adequate contraceptive measures * Signing informed consent patients must be able to understand and be willing to participate in this study, and sign informed consent at the same time Exclusion Criteria: * Donor HBsAg or HBcAb positive and HBV DNA titer test is not within the normal reference value; donor or patient HCV antibody positive and peripheral blood HCV RNA positive; donor or patient HIV antibody positive; donor syphilis test positive * Active central nervous system disease * BMI index\>35 * Allergic to DMSO * Graft-versus-host disease * Septic shock * Systemic steroid therapy is required during cell infusion or cell collection, or there are conditions that researchers believe may require steroid therapy during blood collection or during infusion. In addition to cell collection or infusion, steroids for disease treatment are allowed, and inhaled steroids or hydrocortisone are also allowed for physiological replacement therapy in patients with adrenal insufficiency * Participated in another clinical trial within 4 weeks before enrolling in the study, or intend to participate in another clinical trial throughout the study * According to the judgment of the investigator, it does not meet the situation of cell preparation * Circumstances considered by other researchers to be inappropriate