Comparative investigation of the effects of specific antigen-sensitized DC-CIK and DC-CTL cells against B16 melanoma tumor cells

The use of personalized adoptive immunotherapy as a potential novel approach is promising in the treatment of tumors resistant to conventional therapies. In the present study, dendritic cell (DC)‑cytokine‑induced killer (CIK) and DC‑cytotoxic lymphocyte (CTL) cells were cultured to examine their phenotype, proliferation and cytotoxicity against B16 melanoma tumor cells. In addition, comparative investigations of the effect of specific antigen‑sensitized DC‑CIK and DC‑CTL cells against B16 melanoma tumor cells were performed in vitro and in vivo. The results showed that the phenotypes of the co‑cultured cells were altered, and DCs promoted DC‑CIK cell and DC‑CTL cell differentiation and maturation in vitro. Lactate dehydrogenase cytotoxic analysis indicated that the cytotoxicity increased as the effector to target ratio increased between 10:1 and 40:1, and the cytotoxic effect towards B16 melanoma cells by DC‑CTL cells was significantly higher, compared with that of DC‑CIK cells. To further examine the antineoplastic efficacy of DC‑CIK and DC‑CTL cells in vivo, the present study performed tail‑intravenous injection of DC‑CIK cells and DC‑CTL cells, which attenuated B16 melanoma cell‑engrafted tumor growth, induced G0/G1 cell cycle arrest and accelerated cell apoptosis. Taken together, these results suggested that the use of DC‑CTL or DC‑CIK cell therapy as a personalized adoptive immunotherapy may regulate immune status and inhibit tumor growth in vivo. In addition, the experiments indicated that DC‑CTL cells offer superior antineoplastic activity, compared with DC‑CIK cells against B16 melanoma tumor cells.