Effect of Dendritic Cell Based Cancer Vaccine Using Allogeneic Tumor Cell Lysate in Melanoma Pulmonary Metastasis Model

BACKGROUND: To perform the successful dendritic cell-based cancer immunotherapy one of the main issues to be solved is the source of antigen for DC pulsing. Limitations occur by using auto-tumor lysate due to the difficulties obtaining enough tumor tissue(s) quantitatively as well as qualitatively. In this study the possibility of allogeneic tumor cell lysate as a DC pulsing antigen has been tested in mouse melanoma pulmonary metastasis model. METHODS: B16F10 melanoma cells (1x10(5)/mouse) were inoculated intravenously into the C57BL/6 mouse. Therapeutic DCs were cultured from the bone marrow myeloid lineage cells with GM-CSF and IL-4 (1,000 U/ml each) for 7 days and pulsed with lysate of either autologous B16F10 (B-DC), allogeneic K1735 (C3H/He origin; K-DC) or CloneM3 (DBA2 origin; C-DC) melanoma cells for 18 hrs. Pulsed-DCs (1x10(6)/mouse)[CGP1] were injected i.p. twice with one week interval starting from the day 1 after tumor cell inoculation. RESULTS: Without observable toxicity, allogeneic tumor cell lysate pulsed-DC induced the significantly better anti-tumor response (tumor scale: 2.7+/-0.3, 0.7+/-0.3 and 0.3+/-0.2 for saline, B-DC and C-DC treated group, respectively). Along with increased tumor specific lymphocyte proliferations, induction of IFN-gamma secretion against both auto- and allo-tumor cell lysates was observed from the DC treated mice. (w/B16F10-lysate: 44.97+/-10.31, 1787.94+/-131.18, 1257.15+/-48.27, w/CloneM3 lysate: 0, 1591.13+/-1.83, 1460.47+/-86.05 pg/ml for saline, B-DC and C-DC treated group, respectively) Natural killer cell activity was also increased in the mice treated with tumor cell lysate pulsed-DC (8.9+/-[CGP2]0.1, 11.6+/-0.8 and 12.6+/-0.7% specific NK activity for saline, B-DC and C-DC treated group, respectively). CONCLUSION: Conclusively, promising data were obtained that allogeneic-tumor cell lysate can be used as a tumor antigen for DC-based cancer immunotherapy.

Comparison of Monocyte Selection Method by Immunomagnetic Adsorption or Adherence for the Generation of Dendritic cells / 대한수혈학회지

BACKGROUND: Dendritic cells (DCs) are the most potent stimulators of immune response including antitumor response. DCs are currently being pursued clinically in the development of cancer vaccines; therefore there are demands for large-scale and clinical-grade generation of DCs. In the present study, to find out the most efficient separation method of DC precursors, we compared two separation methods, namely, based on magnetic based selection and plastic adherence selection. METHODS: MNCs were collected by leukapheresis from healthful donors and separated by CD14 + immunomagnetic adsorption or plastic adherence. DC precursors separated using the two methods were differenciated in the same condition. Matured DCs were compared in terms of yield, viability, the expression of surface markers and ability to induce immune reaction. RESULTS: This study demonstrated that mature DCs from CD14 + monocytes separated using CD14 + immunomagnetic adsorption had higher expression of surface markers of DCs, yield (1.9 +/-0.5% vs. 0.5 +/-0.2%), viability (94.7 +/-2.5% vs. 72.8 +/-7.5%) and better functionality in inducing immune reaction than those from plastic adherent cells. CONCLUSION: These results demonstrated that CD14 + immunomagnetic adsorption was found to be more effective than the adherent selection for the generation of DCs. This study will allow researcher to facilitate choosing the appropriate protocol to obtain DCs.