title: TNF-alpha is critical for antitumor but not antiviral T cell immunity in mice.
abstract: TNF-alpha antagonists are widely used in the treatment of inflammatory and autoimmune diseases, but their use is associated with reactivation of latent infections. This highlights the importance of TNF-alpha in immunity to certain pathogens and raises concerns that critical aspects of immune function are impaired in its absence. Unfortunately, the role of TNF-alpha in the regulation of T cell responses is clouded by a myriad of contradictory reports. Here, we show a role for TNF-alpha and its receptors, TNFR1 and TNFR2, specifically in antitumor immunity. TNF-alpha-deficient mice exhibited normal antiviral responses associated with strong inflammation. However, TNF-alpha/TNFR1-mediated signals on APCs and TNF-alpha/TNFR2 signals on T cells were critically required for effective priming, proliferation, and recruitment of tumor-specific T cells. Furthermore, in the absence of TNF-alpha signaling, tumor immune surveillance was severely abrogated. Finally, treatment with a CD40 agonist alone or in combination with TLR2 stimuli was able to rescue proliferation of TNF-alpha-deficient T cells. Therefore, TNF-alpha signaling may be required only for immune responses in conditions of limited immunostimulatory capacity, such as tumor surveillance. Importantly, these results suggest that prolonged continuous TNF-alpha blockade in patients may have long-term complications, including potential tumor development or progression.
authors.affiliation: The Campbell Family Institute for Breast Cancer Research, Ontario Cancer Institute, Toronto, Ontario, Canada.
authors.forename: Thomas
authors.initials: T
authors.lastname: Calzascia
authors.forename: Marc
authors.initials: M
authors.lastname: Pellegrini
authors.forename: Håkan
authors.initials: H
authors.lastname: Hall
authors.forename: Laurent
authors.initials: L
authors.lastname: Sabbagh
authors.forename: Nobuyuki
authors.initials: N
authors.lastname: Ono
authors.forename: Alisha R
authors.initials: AR
authors.lastname: Elford
authors.forename: Tak W
authors.initials: TW
authors.lastname: Mak
authors.forename: Pamela S
authors.initials: PS
authors.lastname: Ohashi
mesh_terms: D000818:Animals; D000938:Antigen-Presenting Cells / Q000276:immunology; D023201:CD40 Ligand / Q000235:genetics / Q000276:immunology; D049109:Cell Proliferation; D002478:Cells, Cultured; D006801:Humans; D007157:Immunologic Surveillance / Q000235:genetics; D007249:Inflammation / Q000235:genetics / Q000276:immunology; D008216:Lymphocytic Choriomeningitis / Q000235:genetics / Q000276:immunology*; D008217:Lymphocytic choriomeningitis virus / Q000276:immunology*; D051379:Mice; D018345:Mice, Knockout; D009369:Neoplasms / Q000235:genetics / Q000276:immunology*; D047888:Receptors, Tumor Necrosis Factor, Type I / Q000235:genetics / Q000276:immunology; D047889:Receptors, Tumor Necrosis Factor, Type II / Q000235:genetics / Q000276:immunology; D015398:Signal Transduction / Q000235:genetics / Q000276:immunology; D013601:T-Lymphocytes / Q000276:immunology*; D051195:Toll-Like Receptor 2 / Q000235:genetics / Q000276:immunology; D014409:Tumor Necrosis Factor-alpha / Q000235:genetics / Q000276:immunology*
chemical_list: D047888:Receptors, Tumor Necrosis Factor, Type I; D047889:Receptors, Tumor Necrosis Factor, Type II; C493486:Tlr2 protein, mouse; C506236:Tnfrsf1a protein, mouse; D051195:Toll-Like Receptor 2; D014409:Tumor Necrosis Factor-alpha; D023201:CD40 Ligand