title: Administration of interleukin-12 enhances the therapeutic efficacy of dendritic cell-based tumor vaccines in mouse hepatocellular carcinoma.
abstract: Dendritic cells (DCs) are potent antigen-presenting cells that are capable of priming systemic antitumor immune response. Here, we evaluated the combined effectiveness of tumor lysate-pulsed DC immunization and interleukin (IL)-12 administration on the induction of antitumor immunity in a mouse hepatocellular carcinoma (HCC) model. Mouse DCs were pulsed with lysate of BNL 1ME A.7R.1 (BNL), a BALB/c-derived HCC cell line, and then injected into syngeneic mice in combination with systemic administration of IL-12. Lymphocytes from mice treated with BNL lysate-pulsed DCs and IL-12 showed stronger cytolytic activity and produced higher amounts of IFN-gamma than those from mice treated with BNL lysate-pulsed DCs alone. Although immunization with BNL lysate-pulsed DCs alone did not lead to complete regression of established tumors, it significantly inhibited tumor growth compared with vehicle injection. Importantly, the combined therapy of BNL lysate-pulsed DCs and IL-12 resulted in tumor rejection or significant inhibition of tumor growth compared with mice treated with BNL lysate-pulsed DCs alone. In vivo lymphocyte depletion experiments demonstrated that this combination was dependent on both CD8+ and CD4+ T cells, but not natural killer cells. These results demonstrated that IL-12 administration enhanced the therapeutic effect of immunization of tumor lysate-pulsed DCs against HCC in mice. This combination of IL-12 and DCs may be useful for suppressing the growth of residual tumor after primary therapy of human HCC.
authors.affiliation: Department of Internal Medicine and Therapeutics, Osaka University Graduate School of Medicine, Osaka 565-0871, Japan.
authors.forename: T
authors.initials: T
authors.lastname: Tatsumi
authors.forename: T
authors.initials: T
authors.lastname: Takehara
authors.forename: T
authors.initials: T
authors.lastname: Kanto
authors.forename: T
authors.initials: T
authors.lastname: Miyagi
authors.forename: N
authors.initials: N
authors.lastname: Kuzushita
authors.forename: Y
authors.initials: Y
authors.lastname: Sugimoto
authors.forename: M
authors.initials: M
authors.lastname: Jinushi
authors.forename: A
authors.initials: A
authors.lastname: Kasahara
authors.forename: Y
authors.initials: Y
authors.lastname: Sasaki
authors.forename: M
authors.initials: M
authors.lastname: Hori
authors.forename: N
authors.initials: N
authors.lastname: Hayashi
mesh_terms: D000818:Animals; D015496:CD4-Positive T-Lymphocytes / Q000276:immunology; D018414:CD8-Positive T-Lymphocytes / Q000276:immunology; D019496:Cancer Vaccines / Q000276:immunology*; D003602:Cytotoxicity, Immunologic; D003713:Dendritic Cells / Q000276:immunology*; D004357:Drug Synergism; D005260:Female; D016219:Immunotherapy, Adoptive / Q000379:methods*; D007371:Interferon-gamma / Q000096:biosynthesis; D018664:Interleukin-12 / Q000494:pharmacology*; D007694:Killer Cells, Natural / Q000276:immunology; D008114:Liver Neoplasms, Experimental / Q000276:immunology / Q000628:therapy*; D051379:Mice; D008807:Mice, Inbred BALB C; D009368:Neoplasm Transplantation; D011994:Recombinant Proteins / Q000494:pharmacology; D014407:Tumor Cells, Cultured
chemical_list: D019496:Cancer Vaccines; D011994:Recombinant Proteins; D018664:Interleukin-12; D007371:Interferon-gamma