Depletion of Carcinoma-Associated Fibroblasts and Fibrosis Induces Immunosuppression and Accelerates Pancreas Cancer with Reduced Survival Suppressed immune surveillance with increased CD4+Foxp3+ T regulatory cells was observed in myofibroblast-depleted mouse tumors. Although myofibroblast-depleted tumors did not respond to gemcitabine, anti-CTLA4 immunotherapy reversed disease acceleration and prolonged animal survival. [Cancer Cell] Abstract miR-155 Activates Cytokine Gene Expression in Th17 Cells by Regulating the DNA-Binding Protein Jarid2 to Relieve Polycomb-Mediated Repression Researchers found defective T helper 17 (Th17) cell cytokine expression in miR-155-deficient CD4+ T cells in vitro and in vivo. Mir155 was bound by Th17 cell transcription factors and was highly expressed during Th17 cell differentiation. miR-155-deficient Th17 and regulatory T cells expressed increased amounts of Jarid2, a DNA-binding protein that recruits the Polycomb Repressive Complex 2 to chromatin. [Immunity] Abstract | Graphical Abstract Lymph Node Stromal Cells Acquire Peptide-MHCII Complexes from Dendritic Cells and Induce Antigen-Specific CD4+ T Cell Tolerance Researchers found a novel, alternative mechanism where lymph node-resident stromal cells tolerize CD4+ T cells through the presentation of self-antigens via transferred peptide-MHCII complexes of dendritic cell origin. [J Exp Med] Abstract Disruption of CXCR2-Mediated MDSC Tumor Trafficking Enhances Anti-PD1 Efficacy Tumor signaling of programmed death 1 (PD1) on T cells and expansion of myeloid-derived suppressor cells (MDSCs) are major mechanisms of tumor immune escape. Researchers sought to target these pathways in rhabdomyosarcoma, the most common soft tissue sarcoma of childhood. [Sci Transl Med] Abstract Adenosine Triphosphate Acts as a Paracrine Signaling Molecule to Reduce the Motility of T Cells Investigators showed a novel form of cell-to-cell communication based on adenosine triphosphate (ATP). ATP released by stimulated T cells induces P2X4/P2X7-mediated calcium waves in neighboring lymphocytes. Data obtained in lymph node slices suggest that, during T-cell priming, ATP acts as a paracrine messenger to reduce the motility of lymphocytes and that this may be relevant to allow optimal tissue scanning by T cells. [EMBO J] Abstract Foxp3+ Regulatory T Cells Promote Lung Epithelial Proliferation Scientists demonstrated that intratracheal delivery of endotoxin (lipopolysaccharide) elicits alveolar epithelial damage from which the epithelium undergoes proliferation and repair. Epithelial proliferation coincided with an increase in Foxp3+ regulatory T cells in the lung during the course of resolution. [Mucosal Immunol] Abstract IL-15 Induces Alloreactive CD28– Memory CD8 T Cell Proliferation and CTLA4-Ig Resistant Memory CD8 T Cell Activation Candidate proliferative cytokines were tested for synergy with alloantigen in stimulating CD28– memory CD8 T cell proliferation. Addition of interleukin (IL)-15, but not IL-2 or IL-7, to co-cultures of CD28– or CD28+ memory CD8 T cells and allogeneic B cells rescued proliferation of the CD28– and enhanced CD28+ memory T cell proliferation. [Am J Transplant] Abstract Expression of IL-2 in β Cells by AAV8 Gene Transfer in Pre-Diabetic NOD Mice Prevents Diabetes through Activation of FoxP3-Positive Regulatory T Cells The local β-cell expression of interleukin (IL)-2 increased the number of CD4+CD25+FoxP3+ cells in the pancreatic lymph node and SPL in both non-obese diabetic (NOD) and C57BL/6 mice. Results demonstrate that local, low expression of mIL-2 in islets prevents progress of diabetes through the regulation of regulatory T cells. [Gene Ther] Abstract Murine Th9 Cells Promote the Survival of Myeloid Dendritic Cells in Cancer Immunotherapy In melanoma B16-OVA tumor-bearing mice, dendritic cells (DCs) conditioned by T-helper (Th)-9 cells lived longer and induced stronger anti-tumor response than control DCs did in vivo. Mechanistic studies revealed that interleukin (IL)-3 but not IL-9 secreted by Th9 cells was responsible for the prolonged survival of DCs. [Cancer Immunol Immunother] Abstract Induction of Antigen-Specific Cytotoxic T Lymphocytes by Fusion Cells Generated from Allogeneic Plasmacytoid Dendritic and Tumor Cells Two types of allogeneic cells, a leukemia plasmacytoid dendritic cell (pDC) line (PMDC05) and pancreatic cancer cell lines (PANC-1 or MIA PaCa-2), were fused instead of autologous monocyte-derived dendritic cells and tumor cells. Scientists created four types of pDC/tumor fusion cells by alternating fusion partners and treating with lipopolysaccharide and examined their antitumor immune responses. [Int J Oncol] Abstract |