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In addition to antigen-driven signals,T cells need co-stimulatory signals for robust activation. Several receptors,including members of the tumor necrosis factor receptor superfamily (TNFRSF),can deliver co-stimulatory signals to T cells. Thioredoxin interacting protein (TXNIP) is an important inhibitor of glucose uptake and cell proliferation,but it is unknown how TXNIP is regulated in T cells. The aim of this study was to determine expression levels and regulation of TXNIP in human T cells. We found that na{\{i}}ve T cells express high levels of TXNIP and that treatment of blood samples with TNF results in rapid down-regulation of TXNIP in the T cells. TNF-induced TXNIP down-regulation correlated with increased glucose uptake. Furthermore we found that density gradient centrifugation (DGC) induced down-regulation of TXNIP. We demonstrate that DGC induced TNF production that paralleled the TXNIP down-regulation. Treatment of blood with toll-like receptor (TLR) ligands induced TNF production and TXNIP down-regulation suggesting that damage-associated molecular patterns (DAMPs) such as endogenous TLR ligands released during DGC play a role in DGC-induced TXNIP down-regulation. Finally we demonstrate that TNF-induced TXNIP down-regulation is dependent on caspase activity and is caused by caspase-mediated cleavage of TXNIP." View Publication

MicroRNAs (miRNA) are small noncoding RNAs that regulate gene expression by targeting mRNAs in a sequence specific manner,thereby determining their degradation or inhibiting translation. They are involved in processes such as proliferation,differentiation and apoptosis by fine-tuning the expression of genes underlying such events. The expression of specific miRNAs is involved in hematopoietic differentiation and their deregulation contributes to the development of hematopoietic malignancies such as acute myeloid leukemia (AML). miR-130a is over-expressed in AML. Here we show that miR-130a is physiologically expressed in myeloblasts and down-regulated during monocyte differentiation. Gain- and loss-of-function experiments performed on CD34+ human hematopoietic stem cells confirmed that expression of miR-130a inhibits monocyte differentiation by interfering with the expression of key transcription factors HOXA10,IRF8,KLF4,MAFB and PU-1. The data obtained in this study highlight that the correct modulation of miR-130a is necessary for normal differentiation to occur and confirming that deregulation of this miRNA might underlie the differentiation block occurring in AML. View Publication

Environmental factors contribute to Type 1 diabetes (T1D) susceptibility. The gut microbiome,which includes bacteria,viruses,and fungi,contributes to this environmental influence,and can induce immunological changes. The gut viral component of the microbiome,related to T1D has mostly focused on coxsackieviruses and rotavirus. The role of norovirus,another common enteric virus,in susceptibility to T1D was hitherto unknown. Norovirus is highly infectious and encountered by many children. We studied the mouse norovirus 4 (MNV4),related to human noroviruses,in the Non-obese diabetic (NOD) mouse model,to determine its role in influencing susceptibility to T1D. We infected MNV-free NOD mice with MNV4 by exposing the mice to MNV4-positive bedding from an endemically-infected mouse colony to mimic a natural infection. Control MNV-free NOD mice were exposed to MNV-free bedding from the same colony. Interestingly,MNV4 infection protected NOD mice from the development of T1D and was associated with an expansion of Tregs and reduced proinflammatory T cells. We also found MNV4 significantly modified the gut commensal bacteria composition,promoting increased $\alpha$-diversity and Firmicutes/Bacteroidetes ratio. To elucidate whether T1D protection was directly related to MNV4,or indirectly through modulating gut microbiota,we colonized germ-free (GF) NOD mice with the MNV4-containing or non-MNV4-containing viral filtrate,isolated from filtered fecal material. We found that MNV4 induced significant changes in mucosal immunity,including altered Tuft cell markers,cytokine secretion,antiviral immune signaling markers,and the concentration of mucosal antibodies. Systemically,MNV4-infection altered the immune cells including B cell subsets,macrophages and T cells,and especially induced an increase in Treg number and function. Furthermore,in vitro primary exposure of the norovirus filtrate to na{\{i}}ve splenocytes identified significant increases in the proportion of activated and CTLA4-expressing Tregs. Our data provide novel knowledge that norovirus can protect NOD mice from T1D development by inducing the expansion of Tregs and reducing inflammatory T cells. Our study also highlights the importance of distinguishing the mucosal immunity mediated by bacteria from that by enteric viruses." View Publication

As the prognosis of invasive aspergillosis remains unacceptably poor in patients undergoing hematopoietic stem cell transplantation (HSCT),there is a growing interest in the adoptive transfer of antifungal effector cells,such as Natural Killer (NK) cells. Because immunosuppressive agents are required in most HSCT recipients,knowledge of the impact of these compounds on the antifungal activity of NK cells is a prerequisite for clinical trials. We,therefore,assessed the effect of methylprednisolone (mPRED),cyclosporin A (CsA) and mycophenolic acid (MPA) at different concentrations on proliferation,apoptosis/necrosis,and the direct and indirect anti-Aspergillus activity of human NK cells. Methylprednisolone decreased proliferation and increased apoptosis of NK cells in a significant manner. After seven days,a reduction of viable NK cells was seen for all three immunosuppressants,which was significant for MPA only. Cyclosporin A significantly inhibited the direct hyphal damage by NK cells in a dose-dependent manner. None of the immunosuppressive compounds had a major impact on the measured levels of interferon-$\gamma$,granulocyte-macrophage colony-stimulating factor and RANTES (regulated on activation,normal T cell expressed and secreted; CCL5). Our data demonstrate that commonly used immunosuppressive compounds have distinct effects on proliferation,viability and antifungal activity of human NK cells,which should be considered in designing studies on the use of NK cells for adoptive antifungal immunotherapy. View Publication

Immunosuppression increases the risk of cancers that are associated with viral infection1. In particular,the risk of squamous cell carcinoma of the skin-which has been associated with beta human papillomavirus ($\beta$-HPV) infection-is increased by more than 100-fold in immunosuppressed patients2-4. Previous studies have not established a causative role for HPVs in driving the development of skin cancer. Here we show that T cell immunity against commensal papillomaviruses suppresses skin cancer in immunocompetent hosts,and the loss of this immunity-rather than the oncogenic effect of HPVs-causes the markedly increased risk of skin cancer in immunosuppressed patients. To investigate the effects of papillomavirus on carcinogen-driven skin cancer,we colonized several strains of immunocompetent mice with mouse papillomavirus type 1 (MmuPV1)5. Mice with natural immunity against MmuPV1 after colonization and acquired immunity through the transfer of T cells from immune mice or by MmuPV1 vaccination were protected against skin carcinogenesis induced by chemicals or by ultraviolet radiation in a manner dependent on CD8+ T cells. RNA and DNA in situ hybridization probes for 25 commensal $\beta$-HPVs revealed a significant reduction in viral activity and load in human skin cancer compared with the adjacent healthy skin,suggesting a strong immune selection against virus-positive malignant cells. Consistently,E7 peptides from $\beta$-HPVs activated CD8+ T cells from unaffected human skin. Our findings reveal a beneficial role for commensal viruses and establish a foundation for immune-based approaches that could block the development of skin cancer by boosting immunity against the commensal HPVs present in all of our skin. View Publication

Diffuse large B cell lymphoma (DLBCL) is the commonest disorder derived from the B-lymphocytes. Inhibiting the immune checkpoint through naturalizing programmed death-1 (PD-1) and programmed death ligand 1 (PD-L1) is proved to be a successful therapeutic regime for lymphoma. Long non-coding RNAs (lncRNAs) are unceasingly reported to be promising biological targets for the cancer therapies. This study planned to explore the regulation of small nucleolar RNA host gene 14 (SNHG14) on DLBCL. SNHG14 level in DLBCL samples and cell lines was analyzed by GEPIA bioinformatics tool and RT-qPCR. Biological functions of SNHG14 in DLBCL were detected by CCK-8,colony formation,and transwell invasion assays. Molecular interaction was determined by RNA immunoprecipitation (RIP) and luciferase reporter assays. MiR-5590-3p-related pathway was identified through KEGG pathway analysis applying DAVID6.8 online bioinformatics tool. Effect of SNHG14 on CD8+ T cells was detected by flow cytometry. Results depicted that SNHG14 was upregulated in DLBCL and its depletion retarded proliferation,migration and epithelial-to-mesenchymal transition (EMT). Mechanistically,SNHG14 sponged miR-5590-3p to upregulate Zinc finger E-box binding homeobox 1 (ZEB1),and ZEB1 transcriptionally activated SNHG14 and PD-L1 to promote the immune evasion of DLBCL cells. In conclusion,we firstly showed that SNHG14/miR-5590-3p/ZEB1 positive feedback loop promoted diffuse large B cell lymphoma progression and immune evasion through regulating PD-1/PD-L1 checkpoint,indicating that targeting SNHG14 was a potential approach to improve the efficacy of immunotherapy in DLBCL. View Publication

The association between type 2 diabetes (T2D) pathogenesis and immune-mediated tissue damage and insulin resistance suggests that T2D patients might benefit from the suppression of pathogenic inflammation. Foxp3+ Treg cells are crucial suppressors of inflammation,but the differentiation of Foxp3+ Treg cells is not static and is subject to conversion into IL-17-producing Th17-like cells upon receiving external signals. In this study,we examined the production of IL-17 by Treg cells. Compared to non-T2D controls,T2D patients presented significantly higher levels of IL-17-expressing cells in both Foxp3- CD4 T cells and Foxp3+ Treg cells. The frequencies of IL-17-nonexpressing Foxp3+ Treg cells,on the other hand,were not changed. Interestingly,IL-17-expressing Foxp3+ Treg cells were mutually exclusive from IL-10-expressing and TGF-$\beta$-expressing Foxp3+ Treg cells,suggesting that multiple subpopulations exist within the Foxp3+ Treg cells from T2D patients. In T2D patients,the frequencies of IL-17-expressing Foxp3+ Treg cells were positively correlated with the body mass index (BMI) and the HbA1c levels of T2D patients. The frequencies of IL-10-expressing Treg cells,on the other hand,were inversely associated with the BMI of both non-T2D controls and T2D patients. In addition,the suppressive activity of Treg cells was significantly lower in T2D patients than in non-T2D controls. Together,our study uncovered a dysregulation in Foxp3+ Treg cells from T2D patients,characterized by high IL-17 expression and low suppression activity. View Publication

Understanding of the factors governing immune responses in cancer remains incomplete,limiting patient benefit. In this study,we used mass cytometry to define the systemic immune landscape in response to tumor development across five tissues in eight mouse tumor models. Systemic immunity was dramatically altered across models and time,with consistent findings in the peripheral blood of patients with breast cancer. Changes in peripheral tissues differed from those in the tumor microenvironment. Mice with tumor-experienced immune systems mounted dampened responses to orthogonal challenges,including reduced T cell activation during viral or bacterial infection. Antigen-presenting cells (APCs) mounted weaker responses in this context,whereas promoting APC activation rescued T cell activity. Systemic immune changes were reversed with surgical tumor resection,and many were prevented by interleukin-1 or granulocyte colony-stimulating factor blockade,revealing remarkable plasticity in the systemic immune state. These results demonstrate that tumor development dynamically reshapes the composition and function of the immune macroenvironment. View Publication