Extrathymic Generation of Regulatory T Cells in Placental Mammals Mitigates Maternal-Fetal Conflict Regulatory T (Treg) cells, whose differentiation and function are controlled by X chromosome-encoded transcription factor Foxp3, are generated in the thymus (tTreg) and extrathymically (peripheral, pTreg), and their deficiency results in fatal autoimmunity. Researchers demonstrated that a Foxp3 enhancer, conserved noncoding sequence 1, essential for pTreg but dispensable for tTreg cell generation, is present only in placental mammals. [Cell] Abstract Aiolos Promotes TH17 Differentiation by Directly Silencing Il2 Expression Researchers report that under interleukin 17-producing helper T cell (TH17)-polarizing conditions, the transcription factors STAT3 and AhR upregulated the expression of Aiolos, a member of the Ikaros family of transcription factors. Using Aiolos-deficient mice, they demonstrated that Aiolos silenced the Il2 locus, promoting TH17 differentiation in vitro and in vivo. [Nat Immunol] Abstract IL-23 Induces Spondyloarthropathy by Acting on ROR-γt+ CD3+CD4−CD8− Entheseal Resident T Cells Researchers showed that interleukin-23 (IL-23) is essential in enthesitis and acts on previously unidentified IL-23 receptor (IL-23R)+, RAR-related orphan receptor γt (ROR-γt)+CD3+CD4−CD8−, stem cell antigen 1 (Sca1)+ entheseal resident T cells. [Nat Med] Abstract The Receptor Ly108 Functions as a SAP Adaptor-Dependent On-Off Switch for T Cell Help to B Cells and NKT Cell Development The authors found that deletion of receptor Ly108 in CD4+ T cells reversed the adaptor protein SAP−/− phenotype, eliminating the SAP requirement for germinal centers. This potent negative signaling by Ly108 required immunotyrosine switch motifs and SHP-1 recruitment, resulting in high amounts of SHP-1 at the T cell:B cell synapse, limiting T cell:B cell adhesion. [Immunity] Abstract NK Cell-Derived Interferon-γ Orchestrates Cellular Dynamics and the Differentiation of Monocytes into Dendritic Cells at the Site of Infection Researchers showed that, after intraperitoneal infection with Toxoplasma gondii cysts, resident mononuclear phagocytes are replaced by circulating monocytes that differentiate in situ into inflammatory dendritic cells and F4/80+ macrophages. [Immunity] Abstract Long-Term Remission of Diabetes in NOD Mice Is Induced by Nondepleting Anti-CD4 and Anti-CD8 Antibodies Researchers showed that a short course of nondepleting antibodies specific for the CD4 and CD8 coreceptors rapidly reversed clinical disease in recent-onset diabetic NOD mice. Once established, remission was maintained indefinitely and immunity to foreign antigens unimpaired. [Diabetes] Abstract | Press Release Systemic Vaccination Induces Clonally Diverse SIV-Specific CD8+ T-Cell Populations in Systemic and Mucosal Compartments Researchers showed that systemic delivery of prototype vaccine vectors in rhesus monkeys induced SIV (simian immunodeficiency virus)-specific CD8+ T-cell responses in systemic and mucosal compartments with comparable clonal compositions. [Mucosal Immunol] Abstract Harnessing Oncolytic Virus-Mediated Antitumor Immunity in an Infected Cell Vaccine Researchers developed a potent oncolytic vaccine platform, consisting of tumor cells infected with VSV-Δ51. They demonstrated that prophylactic immunization with this infected cell vaccine protected mice from subsequent tumor challenge, and expression of granulocyte-monocyte colony stimulating factor by the virus increased efficacy. [Mol Ther] Abstract Inducible IL10+ Suppressor B Cells Inhibit CNS Inflammation and T Helper 17 Polarization Researchers demonstrated that a synthetic cytokine linking granulocyte-macrophage colony-stimulating factor to MCP3 has enhanced CC-chemokine receptor-mediated intracellular Ca++ mobilization with selective effects on the CD21hiCD24hi CD1.dhi subset of splenic B cells inducing substantial interleukin 10 (IL10) production. [Mol Ther] Abstract Term and Preterm Labor: Decreased Suppressive Activity and Changes in Composition of the Regulatory T-Cell Pool Researchers examined whether there were differences in the percentage of the total CD4+CD127low+/−CD25+FoxP3+-regulatory T (Treg)-cell pool, its suppressive activity and its composition with distinct Treg subsets between preterm and term laboring women. [Immunol Cell Biol] Abstract |