Inclusion Criteria:  1. The subjects or their legal representatives signed the informed consent before the clinical study. 2. Subjects aged 15-70 years. 3. Patients with malignant hematological diseases plan to receive allogeneic peripheral blood stem cell transplantation 4. Patients have no suitable HLA identical sibling donor 5.Patients with malignant hematological diseases plan to receive HLA haploidentical stem cell transplantation 6. Subjects with ECoG score of 0-2.  Exclusion Criteria:  1.Patients have suitable HLA identical sibling donor 2. Patients with severe liver and kidney function (alanine aminotransferase > 2.5 times of the upper normal limit, serum creatinine > 1.5 times of the upper normal limit), cardiopulmonary dysfunction (cardiac function NYHA III / IV, cardiac ejection fraction < 50%, severe obstructive or restrictive ventilation dysfunction); 3. Patients with active infection; 4. patients diagnosed with aplastic anemia before transplantation or died within 2 months after transplantation; 5. Subjects with ECoG score > 2; 6. Patients with secondary tumor; 7. Patients who cannot independently choose to enter or exit clinical trials due to serious central nervous system disease or mental disease.