title: Ligation of CD137 receptor prevents and reverses established anergy of CD8+ cytolytic T lymphocytes in vivo.
abstract: T-cell anergy is a tolerance mechanism defined as a hyporesponsive status of antigen-specific T cells upon prior antigen encounter and is believed to play a critical role in the evasion of tumor immunity and the amelioration of allogeneic transplant rejection. Molecular mechanisms in controlling T-cell anergy are less known. We show here that administration of an agonistic monoclonal antibody (mAb) to CD137, a member of the tumor necrosis factor receptor superfamily, prevents the induction of CD8+ cytolytic T-lymphocyte (CTL) anergy by soluble antigens. More importantly, CD137 mAb restores the functions of established anergic CTLs upon reencountering their cognate antigen. As a result, infusion of CD137 mAb inhibits progressive tumor growth that is caused by soluble tumor antigen-induced tolerance in a P815R model. CD137 mAb also restores proliferation and effector functions of anergic alloreactive 2C T cells in a bone marrow transplantation model. Our results indicate that ligation of CD137 receptor delivers a regulatory signal for T-cell anergy and implicate manipulation of the CD137 pathway as a new approach to break T-cell tolerance.
authors.affiliation: Department of Immunology, Mayo Clinic, Rochester, MN 55905, USA.
authors.forename: Ryan A
authors.initials: RA
authors.lastname: Wilcox
authors.forename: Koji
authors.initials: K
authors.lastname: Tamada
authors.forename: Dallas B
authors.initials: DB
authors.lastname: Flies
authors.forename: Gefeng
authors.initials: G
authors.lastname: Zhu
authors.forename: Andrei I
authors.initials: AI
authors.lastname: Chapoval
authors.forename: Bruce R
authors.initials: BR
authors.lastname: Blazar
authors.forename: W Martin
authors.initials: WM
authors.lastname: Kast
authors.forename: Lieping
authors.initials: L
authors.lastname: Chen
mesh_terms: D000818:Animals; D000911:Antibodies, Monoclonal / Q000008:administration & dosage; D015703:Antigens, CD; D016026:Bone Marrow Transplantation; D017635:Clonal Anergy; D005260:Female; D051379:Mice; D008810:Mice, Inbred C57BL; D008811:Mice, Inbred DBA; D008822:Mice, Transgenic; D009368:Neoplasm Transplantation; D009374:Neoplasms, Experimental / Q000276:immunology; D010047:Ovalbumin / Q000276:immunology; D011828:Radiation Chimera / Q000276:immunology; D017475:Receptors, Nerve Growth Factor / Q000819:agonists / Q000037:antagonists & inhibitors / Q000378:metabolism*; D018124:Receptors, Tumor Necrosis Factor / Q000819:agonists / Q000037:antagonists & inhibitors / Q000378:metabolism*; D015398:Signal Transduction; D013602:T-Lymphocytes, Cytotoxic / Q000276:immunology*; D014184:Transplantation, Homologous; D053261:Tumor Necrosis Factor Receptor Superfamily, Member 9
chemical_list: D000911:Antibodies, Monoclonal; D015703:Antigens, CD; D017475:Receptors, Nerve Growth Factor; D018124:Receptors, Tumor Necrosis Factor; C505715:Tnfrsf9 protein, mouse; D053261:Tumor Necrosis Factor Receptor Superfamily, Member 9; D010047:Ovalbumin