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A promising area of investigation is the use of cancer vaccines to eliminate residual tumor cells. Dendritic cells (DCs) are potent professional antigen-presenting cells able to induce primary immune responses. DCs capture and process antigens into peptides and present them to T cells and B cells through MHC class I and II molecules. An alternative approach to the induction of antitumor immunity is the use of fusions of DCs and tumor cells. In this approach, a broad spectrum of tumor-associated antigens, including those known and unidentified, are processed endogenously and presented by MHC class I and II pathways in the context of costimulatory signals. In animal studies, vaccination with DC/tumor fusion cells results in the elimination of established lung metastasis. Preclinical human studies have demonstrated that DC/tumor fusion cells induce antigen-specific polyclonal cytotoxic T-lymphocyte responses against autologous tumor in vitro. In clinical studies, vaccination of cancer patients with autologous DC/tumor fusion cells is associated with immunological and clinical responses in a subset of patients. Future studies should be investigated to improve the immunogenicity of DC/tumor fusion cell preparations. This review provides a general overview of the DC/tumor fusion cell-based vaccine and summarizes some of the recent advances in this field. [ABSTRACT FROM AUTHOR]

Background: The prevention of recurrence of hepatocellular carcinoma (HCC) after treatment is very important for improvement of the prognosis of HCC patients. Dendritic cells (DCs) are potent antigen-presenting cells that can prime naive T cells to induce a primary immune response. We attempted to induce preventive antitumor immunity against HCC by immunizing BALB/c mice with fusions of DCs and HCC cells.Methods: Murine bone marrow-derived DCs and a murine HCC cell line. BNL cells, were fused by treatment with 50% polyethyleneglvcol (PEG). Fusion efficacy was assessed by the analysis of fusions of BNL cells stained with red fluorescent dye and DCs stained with green fluorescent dye. Mice injected intravenously with DC/BNL fusions were challenged by BNL cell inoculation.Results: About 30% of the PEG-treated non-adherent cells with both fluorescences were considered to be fusion cells. The cell fraction of DC/BNL fusions showed phenotypes of DCs, MHC class II, CD80, CD86, and intercellular adhesion molecule (ICAM)-1, which were not expressed on BNL cells. Mice immunized with the fusions were protected against the inoculation of BNL tumor cells, whereas injection with a mixture of DCs and BNL cells not treated with PEG did not provide significant resistance against BNL cell inoculation. Splenocytes from DC/BNL fusion-immunized mice showed lytic activity against BNL cells.Conclusions: These results demonstrate that immunization with fusions of DCs and HCC cells is capable of inducing preventive antitumor immunity against HCC. [ABSTRACT FROM AUTHOR]