title: Interleukin-10 prevents dendritic cell accumulation and vaccination with granulocyte-macrophage colony-stimulating factor gene-modified tumor cells.
abstract: A wide variety of human tumors express IL-10 for reasons poorly understood. We have analyzed the effect of spontaneous IL-10 expression by a mouse tumor (J558L) on its immunoparalyzing effect. Because "cross-priming" of T cells by host Ag-presenting cells for MHC class I-restricted tumor Ags is a major pathway for induction of tumor immunity and that is enhanced by granulocyte-macrophage (GM) CSF, we expressed this cytokine in J558L cells. GM-CSF-secreting cells were not effective when used for immunization against challenge with the parental tumor. Inhibition of IL-10 expression through an IL-10 antisense retrovirus restored the vaccine efficacy of GM-CSF-producing J558L cells, demonstrating a direct role of IL-10 in paralyzing the GM-CSF-induced antitumor immune response. Since the tumor used for challenge produced IL-10, we conclude that IL-10 interfered primarily with the initiation but not the effector phase of the immune response. Immunohistochemical analysis of the vaccine site showed a GM-CSF-induced accumulation of dendritic cells (DC) (MHC class II+ and DEC-205+) in the absence of IL-10. In the presence of IL-10, DC accumulation was completely inhibited. Together, our results demonstrate an antagonistic effect of IL-10 with respect to GM-CSF-induced DC accumulation and tumor immunity and suggest a new mechanism by which tumors escape immune recognition: namely by preventing APC from obtaining access to tumor Ags.
authors.affiliation: Max-Delbrück-Centrum fur Molekulare Medizin, Berlin, Germany.
authors.forename: Z
authors.initials: Z
authors.lastname: Qin
authors.forename: G
authors.initials: G
authors.lastname: Noffz
authors.forename: M
authors.initials: M
authors.lastname: Mohaupt
authors.forename: T
authors.initials: T
authors.lastname: Blankenstein
mesh_terms: D000818:Animals; D019496:Cancer Vaccines; D003602:Cytotoxicity, Immunologic; D003713:Dendritic Cells / Q000276:immunology / Q000473:pathology*; D015972:Gene Expression Regulation, Neoplastic / Q000276:immunology*; D016178:Granulocyte-Macrophage Colony-Stimulating Factor / Q000235:genetics / Q000276:immunology*; D006801:Humans; D016753:Interleukin-10 / Q000235:genetics / Q000276:immunology*; D051379:Mice; D009374:Neoplasms, Experimental / Q000235:genetics / Q000276:immunology* / Q000473:pathology; D010954:Plasmacytoma / Q000235:genetics / Q000276:immunology* / Q000473:pathology; D014407:Tumor Cells, Cultured; D014611:Vaccination
chemical_list: D019496:Cancer Vaccines; D016753:Interleukin-10; D016178:Granulocyte-Macrophage Colony-Stimulating Factor