title: Requirement for CD70 in CD4+ Th cell-dependent and innate receptor-mediated CD8+ T cell priming.
abstract: Dendritic cell (DC) conditioning by CD4+ T cells, or via engagement of innate receptors, is thought to be essential for CD8+ T cell priming. However, the molecular features that distinguish a conditioned DC from an unconditioned DC are poorly defined. In this study, we investigate the role of CD70, a member of the TNF superfamily that is expressed on activated DC, in CD4+ Th-dependent and -independent CD8+ T cell responses. We demonstrate that CD70 is required for CD4+ T cell-dependent priming of CD8+ T cells as well as priming mediated by the viral signature, dsRNA. Accordingly, mice that were subjected to CD70 blockade during the primary response fail to generate a memory CD8+ T cell response. Furthermore, we find that CD70 is dispensable for CD4+ T cell expansion and help for B cells, thus suggesting a direct role for CD70 in CD8+ T cell priming. Our results show that the innate and adaptive (CD4+ T cells) arms of the immune system use a common signaling pathway in driving CD8+ T cell responses and suggest that expression of CD70 on DC represents the hallmark of conditioned DC.
authors.affiliation: Tenovus Research Laboratory, Cancer Sciences Division, University of Southampton School of Medicine, Southampton General Hospital, Southampton, United Kingdom.
authors.forename: Vadim Y
authors.initials: VY
authors.lastname: Taraban
authors.forename: Tania F
authors.initials: TF
authors.lastname: Rowley
authors.forename: David F
authors.initials: DF
authors.lastname: Tough
authors.forename: Aymen
authors.initials: A
authors.lastname: Al-Shamkhani
mesh_terms: D000818:Animals; D015703:Antigens, CD / Q000276:immunology* / Q000378:metabolism; D001402:B-Lymphocytes / Q000276:immunology; D053282:CD27 Ligand; D015496:CD4-Positive T-Lymphocytes / Q000276:immunology*; D018414:CD8-Positive T-Lymphocytes / Q000276:immunology*; D002478:Cells, Cultured; D003713:Dendritic Cells / Q000276:immunology; D007113:Immunity, Innate / Q000276:immunology*; D007156:Immunologic Memory / Q000276:immunology; D008213:Lymphocyte Activation / Q000276:immunology; D008565:Membrane Proteins / Q000276:immunology* / Q000378:metabolism; D051379:Mice; D011948:Receptors, Antigen, T-Cell / Q000276:immunology*; D018127:Tumor Necrosis Factor Receptor Superfamily, Member 7 / Q000276:immunology / Q000378:metabolism; D048069:Tumor Necrosis Factors / Q000276:immunology* / Q000378:metabolism
chemical_list: D015703:Antigens, CD; D053282:CD27 Ligand; C505772:Cd70 protein, mouse; D008565:Membrane Proteins; D011948:Receptors, Antigen, T-Cell; D018127:Tumor Necrosis Factor Receptor Superfamily, Member 7; D048069:Tumor Necrosis Factors