Clinical Study Of DC-CIK (dendritic cells and cytokine-induced killer cells ) Eliminate Minimal Residual Leukemia

To evaluate the clinical efficacy and safety of allogenic dendritic cells (DCs) and cytokine-induced killer (CIK) cells in the eliminating minimal residual leukemia (MRL).

48 acute leukemia patients with hematological complete remission (CR) but without molecular biological remission (CRM), or patients with minimal residual Leukemia (MRL) were selected from Ping’an Hospital of Shijiazhuang during Jan. 2009 to Jun. 2011. According to the patients’ will, 48 patients divided into combined treatment group and chemotherapy group 24 each. All the patients were in the same general information and disease level. The combined treatment group was treated with DC-CIK and consolidation chemotherapy, and the chemotherapy group was treated with consolidation chemotherapy. PBMCs were collected from healthy donors (the patient's parents or children) to prepare DC-CIK cells. DC-CIK cells were intravenous injected into patients once every 15 days, a total of 4-6 times infusion. The blood routine, bone marrow cells, leukemia related genes, urine and stool routine, liver and kidney biochemistry function, and ECG were observed. Changes of peripheral lymphocyte subsets in patients were detected by flow cytometry. Adverse reactions were examined.

(1)Eleven cases in the combined treatment group achieved CRM, and the CRM rate was 45.8%; whereas only 2 cases in the chemotherapy group achieved CRM and the CRM rate was 8.3%,the difference was statistically significant(χ2=8.55, P<0.01).(2) Compared with the chemotherapy group, the CFIM (four-color combination flow cytometric immunophenotype of minimal residual leukemia) negative conversion rate of patients in the combined treatment group was significantly raised (66.7% vs 25.0%,χ²=8.39, P<0.01). (3)The negative conversion rate of MRL was higher in the combined treatment group than the chemotherapy group (66.7% vs25.0%, χ2=8.39, P<0.01). (4) After treatment the ratio of CD4+/CD8+ cells was significant increased than before treatment in the combined treatment group (1.3±0.4 vs 0.8±0.4, P<0.05). (5)The complete remission rate (CCR) of patients in the combined treatment group after 3 years was 79.2%, while that in the chemotherapy group was 45.8% (χ2=5.69, P<0.05).(6)No dysfunction of critical organs such as heart, liver and kidney and serious adverse reactions were observed while DC-CIK cells infusion.

DC-CIK combined with chemotherapy can inhibit leukemia gene, promote the negative conversion rate of CFIM, facilitate the clear of MRL, improve immune function and prolong remission of the patients.No serious adverse reactions were found in patients with DC-CIK infusion.

No relevant conflicts of interest to declare.