• Age 12-65 (inclusive)；

• Patients with recurrent hematologic tumors after allogeneic hematopoietic stem cell transplantation；

• Basically normal liver and kidney function (as demonstrated by the following laboratory tests prior to initial γ9δ2 T cell therapy)

‣ Alanine transaminase/aspartate transaminase \< 2.5×ULN；

⁃ serum creatinine \< 1.5×ULN；

⁃ total bilirubin level \< 1.5×ULN；

• No obvious hereditary disease;

• Normal cardiac function, cardiac ejection index above 55%;

• Women of reproductive age (15 to 49 years) must undergo a pregnancy test within 7 days before starting treatment and the result is negative, and use contraception during the clinical trial period and within 3 months after the last cell transfusion;

• Sign informed consent.