Project description:Recent studies have suggested that formation of supramolecular activation cluster (SMAC), a large ‘immunological synapse’ composed of various signaling complexes, enhances CD4+ T cell activation. Critically, although the composition of SMAC is known, the proteins involved in SMAC formation have not been fully investigated. We identified that intraflagellar transport 20 (IFT20) play central roles in the effector functino of CD4+ T cells.
Project description:Human FOXP3+CD25+CD4+ regulatory T cells (Tregs) play a dominant role in the maintenance of immune homeostasis. Several genes are known to be important for murine Tregs, but for human Tregs the genes and underlying molecular networks controlling the suppressor function still largely remain unclear. We here performed a high-time-resolution dynamic analysis of the transcriptome during the very early phase of human Treg/ CD4+ T-effector cell activation. After constructing a correlation network specific for Tregs based on these dynamic data, we described a strategy to identify key genes by directly analyzing the constructed undirected correlation network. Six out of the top 10 ranked key hubs are known to be important for Treg function or involved in autoimmune diseases. Surprisingly, PLAU (the plasminogen activator urokinase) was among the 4 new key hubs. We here show that PLAU was critical for expression regulation of FOXP3, EOS and several other important Treg genes and the suppressor function of human Tregs. Moreover, we found Plau inhibits murine Treg development and but promotes the suppressive function. Further analysis unveils that PLAU is particularly important for memory Tregs and that PLAU mediates Treg suppressor function via STAT5 and ERK signaling pathways. Our study shows the potential for identifying novel key genes for complex dynamic biological processes using a network strategy based on high-time-resolution data, and highlights a critical role of PLAU in both human and murine Tregs. The construction of a dynamic correlation network of human Tregs provides a useful resource for the understanding of Treg function and human autoimmune diseases. The high-time-resolution time-series transcriptomic data during the very early phase of human Treg/Teff activation could be generally used for further mechanistic analysis of human Treg function. These data could be further used for biological network analysis, dynamic analysis, modeling by experimental researchers, bioinformaticians, computational biologists and systems biologists. We have measured the genome-wide expression of 38,500 genes (probes) by performing a high-time-resolution time-series analysis during the activation process of human regulatory T cells /CD4+ T-effector cells at 19 time points for the first 6h with an equal interval of 20 min. We have also overexpressed the GARP gene in human effector T cells and measured the genome-scale expression for the GARP-overexpressed cells and ThGFP cells at time point 0, 100 and 360min following activation. The stimulation source used in this work is a combination of anti-CD3/-CD28 Dynal beads with IL2 100U/ml.
Project description:Crohn’s disease (CD) is one of the major forms of inflammatory bowel disease (IBD), characterized by chronic inflammation of the gastrointestinal tract. CD is associated with aberrant Th1 and Th17 responses accompanied by high levels of IFN-g and IL-17, respectively. Protein kinase 2 (CK2) is a highly conserved serine-threonine kinase that is involved in several signal transduction pathways which regulate inflammatory responses. CK2 promotes Th17 cell differentiation and suppresses the generation of Foxp3+ regulatory T cells. The function of CK2 in CD4+ T-cells during the pathogenesis of CD is unknown. We utilized T-cell induced colitis model, transferring CD45RBhi naïve CD4+ T-cells from CK2afl/fl littermate control and CK2afl/fldLck-Cre mice into Rag1-/- mice. We demonstrate that CD4+ T-cells from CK2afl/fldLck-Cre mice fail to induce wasting disease and significant intestinal inflammation, which is associated with decreased IL-17A+, IFN-g+ and double positive IL-17A+ IFN-g+ CD4+ T-cells in the spleen and colon. Further, we determine that CK2a regulates CD4+ T-cell proliferation through a cell-intrinsic manner. CK2a is also important in controlling CD4+ T-cell responses by regulating NFAT2, which is vital for T-cell activation and proliferation. Thus, our data demonstrate that CK2a contributes to the pathogenesis of colitis by promoting CD4+ T-cell proliferation and Th1 and Th17 responses, and that targeting CK2 kinase activity may be a novel therapeutic treatment for CD patients.
Project description:Identifying BTLA interacting proteins in mouse CD4+ effector T cells expressing BTLA at endogenous levels and after stimulation with pervanadate.