title: Immunization with a syngeneic tumor infected with recombinant vaccinia virus expressing granulocyte-macrophage colony-stimulating factor (GM-CSF) induces tumor regression and long-lasting systemic immunity.
abstract: A recombinant vaccinia virus encoding the gene for granulocyte-macrophage colony-stimulating factor (rV-GM-CSF) was used to infect the poorly immunogenic murine colon adenocarcinoma cell line, MC-38. Infection of MC-38 tumor cells with rV-GM-CSF completely suppressed the growth of the MC-38 primary tumors, whereas progressively growing tumors were formed in mice injected with MC-38 cells infected with wild type V-Wyeth. Irradiation of the recipient B6 mice before implantation of rV-GM-CSF-infected tumor cells resulted in the development of progressively growing tumors. Moreover, in vivo T-cell depletion studies revealed that growth suppression of the rV-GM-CSF-infected tumor cells was dependent on the presence of both CD4+ and CD8+ T-cell subsets. Subsequent studies established that this immunity was long-lasting and antigen specific, as demonstrated by the protection of rV-GM-CSF-immunized mice from MC-38 tumor challenge but not from challenge with another syngeneic tumor cell type. No such effects were observed when MC-38 tumor cells were infected with recombinant vaccinia viruses expressing interleukin (IL)-2 or IL-6. The results demonstrate that paracrine release of biologically active murine GM-CSF by tumor cells infected with rV-GM-CSF enhances the intrinsic immunogenicity of a poorly immunogenic murine tumor. Presumably the augmentation of tumor immunogenicity induces an antigen-specific T-cell-dependent antitumor response that prevents the formation of primary tumors and protects mice from tumor challenge. Thus in this experimental model, GM-CSF functions as a highly effective vaccine adjuvant.
authors.affiliation: Laboratory of Tumor Immunology and Biology, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892, USA.
authors.forename: J P
authors.initials: JP
authors.lastname: McLaughlin
authors.forename: S
authors.initials: S
authors.lastname: Abrams
authors.forename: J
authors.initials: J
authors.lastname: Kantor
authors.forename: M J
authors.initials: MJ
authors.lastname: Dobrzanski
authors.forename: J
authors.initials: J
authors.lastname: Greenbaum
authors.forename: J
authors.initials: J
authors.lastname: Schlom
authors.forename: J W
authors.initials: JW
authors.lastname: Greiner
mesh_terms: D000230:Adenocarcinoma / Q000276:immunology* / Q000517:prevention & control; D000818:Animals; D019496:Cancer Vaccines; D002460:Cell Line; D003110:Colonic Neoplasms / Q000276:immunology* / Q000517:prevention & control; D005260:Female; D016178:Granulocyte-Macrophage Colony-Stimulating Factor / Q000235:genetics* / Q000378:metabolism; D000882:Haplorhini; D007114:Immunization; D007668:Kidney; D051379:Mice; D008810:Mice, Inbred C57BL; D009368:Neoplasm Transplantation; D011994:Recombinant Proteins; D014407:Tumor Cells, Cultured; D014616:Vaccinia virus / Q000235:genetics*
chemical_list: D019496:Cancer Vaccines; D011994:Recombinant Proteins; D016178:Granulocyte-Macrophage Colony-Stimulating Factor