title: Enhanced in vivo growth and resistance to rejection of tumor cells expressing dominant negative IFN gamma receptors.
abstract: Using a neutralizing monoclonal antibody specific for murine IFN gamma we show that endogenously produced IFN gamma plays an obligate role in mediating LPS-induced rejection of the Meth A fibrosarcoma tumor in syngeneic BALB/c mice. To examine the cellular targets of IFN gamma action, we generated IFN gamma-insensitive tumor cells by stably overexpressing in Meth A a truncated dominant negative form of the murine IFN gamma receptor alpha chain. When implanted in BALB/c mice, IFN gamma-insensitive Meth A cells displayed enhanced tumorigenicity compared with control Meth A cells and were not rejected when tumor-bearing mice were treated with concentrations of LPS that eliminated control tumors. In Meth A immune mice, IFN gamma-insensitive Meth A did not establish tumors while IFN gamma-insensitive tumors grew in a progressive manner. In addition, the IFN gamma-insensitive tumor cells were unable to elicit strong protective immunity to subsequent wild-type tumor challenge. These results show that IFN gamma has direct effects on tumor cell immunogenicity and thus plays an important role in promoting tumor cell recognition and elimination.
authors.affiliation: Center for Immunology, Washington University School of Medicine, St. Louis, Missouri 63110.
authors.forename: A S
authors.initials: AS
authors.lastname: Dighe
authors.forename: E
authors.initials: E
authors.lastname: Richards
authors.forename: L J
authors.initials: LJ
authors.lastname: Old
authors.forename: R D
authors.initials: RD
authors.lastname: Schreiber
mesh_terms: D000818:Animals; D005260:Female; D016898:Interferon-alpha / Q000276:immunology; D007371:Interferon-gamma / Q000276:immunology; D008070:Lipopolysaccharides / Q000494:pharmacology; D051379:Mice; D008807:Mice, Inbred BALB C; D008810:Mice, Inbred C57BL; D016513:Mice, SCID; D009368:Neoplasm Transplantation / Q000276:immunology; D009374:Neoplasms, Experimental / Q000276:immunology* / Q000473:pathology*; D017471:Receptors, Interferon / Q000276:immunology*; D013601:T-Lymphocytes / Q000276:immunology; D014162:Transfection / Q000276:immunology; D014407:Tumor Cells, Cultured; D000096743:Interferon gamma Receptor
chemical_list: D016898:Interferon-alpha; D007371:Interferon-gamma; D008070:Lipopolysaccharides; D017471:Receptors, Interferon; D000096743:Interferon gamma Receptor