Melanoma-Intrinsic β-Catenin Signaling Prevents Anti-Tumor Immunity Researchers identified a melanoma-cell-intrinsic oncogenic pathway that contributes to a lack of T-cell infiltration in melanoma. Using autochthonous mouse melanoma models, they identified the mechanism by which tumor-intrinsic active β-catenin signaling results in T-cell exclusion and resistance to anti-PD-L1/anti-CTLA-4 monoclonal antibody therapy. [Nature] Abstract | Press Release IL-7-Induced Glycerol Transport and TAG Synthesis Promotes Memory CD8+ T Cell Longevity Scientists discovered that IL-7 induces expression of the glycerol channel aquaporin 9 (AQP9) in virus-specific memory CD8+ T cells, but not naive cells, and that AQP9 is vitally required for their long-term survival. [Cell] Abstract | Graphical Abstract | Video Differential Fc-Receptor Engagement Drives an Anti-Tumor Vaccinal Effect Researchers demonstrated that FcγR expression by CD11c+ antigen-presenting cells is required to generate anti-tumor T cell responses upon FcγR-mediated cytotoxicity-mediated tumor clearance. [Cell] Abstract | Graphical Abstract | Press Release Common Clonal Origin of Central and Resident Memory T Cells following Skin Immunization Investigators immunized mice through the skin with a protein antigen, a chemical hapten, or a non-replicating poxvirus. For every abundant resident memory T cell clone generated in the skin, an abundant central memory T cell clone bearing the identical T cell receptor was present in the lymph nodes. [Nat Med] Abstract | Press Release Integrin αvβ8-Mediated TGF-β Activation by Effector Regulatory T Cells Is Essential for Suppression of T-Cell-Mediated Inflammation Scientists showed that effector regulatory T (Treg) cells express high amounts of the integrin αvβ8, which enables them to activate latent transforming growth factor-β (TGF-β). Treg-cell-specific deletion of integrin αvβ8 did not result in a spontaneous inflammatory phenotype, suggesting that this pathway is not important in Treg-cell-mediated maintenance of immune homeostasis. [Immunity] Full Article | Graphical Abstract | Press Release The Autoimmunity-Associated Gene CLEC16A Modulates Thymic Epithelial Cell Autophagy and Alters T Cell Selection Investigators generated Clec16a knock-down mice in the nonobese diabetic model for type 1 diabetes and found that Clec16a silencing protected against autoimmunity. Disease protection was attributable to T cell hyporeactivity, which was secondary to changes in thymic epithelial cell stimuli that drive thymocyte selection. [Immunity] Abstract | Graphical Abstract | Press Release Microbe-Dependent Lymphatic Migration of Neutrophils Modulates Lymphocyte Proliferation in Lymph Nodes Scientist established a photoconversion-based system to monitor the fate of neutrophils recruited to inflamed skin. While neutrophils are efficiently recruited to sites of both microbial and sterile lesions, subsequent re-localization to draining lymph nodes happens only when bacteria are present in the primary lesion. [Nat Commun] Full Article | Press Release Type I Interferons Regulate Eomesodermin Expression and the Development of Unconventional Memory CD8+ T Cells Researchers show that type I interferon signaling in CD8+ T cells directly activates eomesodermin gene expression. Consistent with this observation, the phenotype, function and age-dependent expansion of ‘virtual memory’ CD8+ T cells are strongly affected in absence of type I interferon signaling. [Nat Commun] Full Article | Press Release Immune-Checkpoint Proteins VISTA and PD-1 Nonredundantly Regulate Murine T-Cell Responses To determine whether V-domain immunoglobulin suppressor of T-cell activation (VISTA) synergizes with another immune-checkpoint, programmed death 1 (PD-1), investigators characterized the immune responses in VISTA-deficient, PD-1-deficient (KO) mice and VISTA/PD-1 double KO mice. [Proc Natl Acad Sci USA] Abstract Function and Regulation of Self-Reactive Marginal Zone B Cells in Autoimmune Arthritis Researchers explored the influence of self-reactive innate B cells in the development of collagen-induced arthritis, a mouse model of rheumatoid arthritis. They showed that splenic marginal zone, but not B-1 B cells exhibit spontaneous IgM reactivity to autologous collagen II in naïve mice. [Cell Mol Immunol] Abstract Free Extracellular miRNA Functionally Targets Cells by Transfecting Exosomes from Their Companion Cells The authors describe that extracellular miR-150, extracted from exosomes, is still able to mediate antigen-specific suppression. They determined that this was due to miR-150 association with antibody-coated exosomes produced by B1a cell companions of effector T cells, which resulted in antigen-specific suppression of their function. [PLoS One] Full Article | Press Release Don’t forget to subscribe to Human Immunology News and Immunology of Infectious Disease News!  |