Patient serum cytokine levels before and after cyclophosphamide and T-cell infusions. Serum cytokines were determined before and after 19-28z⁺ T-cell infusion. The first set of patients (CLL-1 to CLL-3) did not receive cyclophosphamide treatment before T-cell infusion, whereas the second set (CLL-5 to CLL-7 and ALL-1) received cyclophosphamide before T-cell infusion. The x-axis represents treatment time course with day 0 being the day of T-cell infusion and day −2 being the day of cyclophosphamide treatment.