Safety and Efficacy of CAR2219 CAR-T Cells in Treatment of Relapsed/refractory CD19/CD22 Positive B Cell Leukemia and Lymphoma

Genetic: CAR2219-T cells Each subject will be infused with single dose of CD2219-CAR-T cells. A classic "3+3" dose escalation will be employed. The low dose is 5×10\^5 /kg, the medium dose is 1×10\^6 /kg, and the high dose is 2×10\^6 /kg. Drug: Fludarabine Fludarabine will be given at a dose of 30 mg/m2/day intravenously (IV) for 3 days prior to the infusion of CD2219-CAR-T cells. Drug: Cyclophosphamide Cyclophosphamide will be given at a dose of 300 mg/m2/day intravenously (IV) for 3 days prior to the infusion of CD2219-CAR-T cells.