Project description:<p>We use next generation sequencing to investigate the different transcriptomes of closely related CD4+ T-cells from healthy human donors to elucidate the genetic programs that underlie their specialized immune functions. Six cell types were included: Regulatory T-cells (CD25hiCD127low/neg with >95% FOXP3+ purity), regulatory T-cells activated using PMA/ionomycin, CD25-CD45RA+ ('naive' helper T-cells), CD25-CD45RO+ ('memory' helper T-cells), activated Th17 cells (>98% IL17A+ purity) and activated IL17-CD4+ T-cells (called 'ThPI'). Poly-T capture beads were used to isolate mRNA from total RNA, and fragment sizes of ~200 were sequenced from both ends on Illumina's genome analyzer. We confirm many of the canonical signature genes of T-cell populations, but also discover new genes whose expression is limited to specific CD4 T-cell lineages, including long non-coding RNAs. Additionally, we find that genes encoded at loci linked to multiple human autoimmune diseases are enriched for preferential expression upon T-cell activation, suggesting that an aberrant response to T-cell activation is fundamental to pathogenesis.</p>
Project description:The transcription factor (TF) Forkhead Box P3 (FOXP3) is constitutively expressed in high levels in natural occurring CD4+CD25+ regulatory T cells (nTreg) and is not only the most accepted marker for that cell population, but is considered lineage determinative. Chromatin immunoprecipitation (ChIP) of transcription factors in combination with genomic tiling microarray analysis (ChIP-on-Chip) has been shown to be an appropriate tool to identify FOXP3 transcription factor binding sites (TFBS) on a genome-wide scale. In combination with microarray expression analysis the ChIP-on-Chip technique allows to identify direct FOXP3 target genes. ChIP-on-Chip analysis of human FOXP3M-NM-^T2 isoform expressed in resting and PMA / ionomycin stimulated Jurkat T cells revealed several thousand putative FOXP3 binding sites and importance of intronic regions for FOXP3 binding. Knowledge of general distribution patterns of FOXP3 TFBS in the human genome under resting and activated conditions contributes to a better understanding of this TF and its influence on direct target genes with importance for Treg cell phenotype and function. ChIP-DNA from FOXP3(M-NM-^T2) expressing Jurkat T cells under resting and PMA / ionomycin stimulated conditions from duplicate experiments was analyzed. FOXP3-specific tiling array data were analyzed in reference to an individual isotype control dataset (J-FOXP3 ChIP'd with FOXP3 antibody vs. J-FOXP3 ChIP'd with isotype control antibody). In total 8 tiling array analyses were performed (2x resting J-FOXP3 with FOXP3-IP, 2x resting J-FOXP3 with isotype-IP, 2x PMA/iono J-FOXP3 with FOXP3-IP, 2x PMA/iono J-FOXP3 with isotype-IP)
Project description:This SuperSeries is composed of the following subset Series:; GSE10232: CTDG in PMA-activated Jurkat cells; GSE10233: CTDG in PMA-activated MM6 cells; GSE10234: CTDG in LPS-activated MM6 cells; GSE10737: CTDG in non-activated Jurkat cells; GSE10738: CTDG in non-activated MM6 cells; GSE10739: LPS and PMA response in parental MM6 cells Experiment Overall Design: Refer to individual Series
Project description:T-helper cells differentiate from naïve precursors into multiple lineages, including Th1, Th2, Th17 and inducible Treg, in humans and mice. The identification of each lineage is currently determined by examination of a small number of genes encoding hallmark cytokines and/or transcription factors in both species To gain a better understanding of human T-helper cell function we have performed detailed transcriptional profiling of highly polarized Th1 and Th2 cells in both resting and activated states examining gene and miRNA expression Naïve CD4 positive T-cells were isolated from peripheral blood of three different human donors. Cells were differenitated into Th1 and Th2 cells in vitro for 28 days to achieve homogeneous cell lineages. Samples were taken at resting state or activated for 4 hours with PMA/Ionomycin.
Project description:ZXDC1 augments the expression of various markers of monocyte/macrophage differentiation when over-expressed in the U937 cell line treated with the phorbol ester PMA. Likewise, knockdown of ZXDC1 restricts the induced expression of these markers. We sought to identify specfic gene targets of ZXDC1 during the process of monocyte/macrophage differentiation in U937 by performing gene expression profiling in cells exhibiting reduced expression of ZXDC1 compared to controls. We used microarray to identify genes regulated by ZXDC during PMA-induced differentiation of U937 monoblasts towards a monocyte/macrophage phenotype An inducible shRNAmir (Tet-On) cell line was established in the U937 background that displayed significant, reproducible, and doxycycline inducible knockdown of ZXDC1. Using this cell line, we created four experimental groups to identify gene targets of ZXDC1 during PMA-induced differention towards a monocyte/macrophage phenotype: Vehicle alone; Vehicle+Doxycycline; PMA alone; PMA+Doxycycline. Each independent group was used for RNA extraction and hybridization on Affymetrix microarray chips.
Project description:Cyclin T1-dependent genes in PMA-activated MM6 cells. HIV-1 is dependent upon cellular co-factors to mediate its replication cycle in CD4+ T cells and macrophages, the two major cell types infected by the virus in vivo. One critical co-factor is Cyclin T1, a subunit of a general RNA polymerase II elongation factor known as P-TEFb. Cyclin T1 is targeted directly by the viral Tat protein to activate proviral transcription. Cyclin T1 is up-regulated when resting CD4+ T cells are activated and during macrophage differentiation or activation, conditions that are also necessary for high levels of HIV-1 replication. Because Cyclin T1 is a subunit of a transcription factor, the up-regulation of Cyclin T1 in these cells results in the induction of cellular genes, some of which might be HIV-1 co-factors. Using shRNA depletions of Cyclin T1 and transcriptional profiling, we identified 54 cellular mRNAs that are Cyclin T1-dependent for their induction in activated CD4+ T cells and during macrophage differentiation and activation. The promoters for these Cyclin T1-dependent genes (CTDGs) are over-represented in two transcription factor binding sites, SREBP1 and ARP1. Notably, 10 of these CTDGs have been reported to be involved in HIV-1 replication, a significant over-representation of such genes when compared to randomly generated lists of 54 genes (p value < 0.00021). SiRNA depletions of two CTDGs identified here, CDK11 and Casein kinase1gamma1, suggest that these genes are also involved in HIV-1 replication. It is therefore likely that the 54 CTDGs identified here include novel HIV-1 co-factors. The presence of CTDGs in the protein space that was available for HIV-1 to sample during its evolution and acquisition of Tat function may provide an explanation for why CTDGs are enriched in viral co-factors. Experiment Overall Design: Using shRNA knockdown of cyclin T1, cyclin T1-dependent genes were identified in PMA-activated MM6 cells.
Project description:c-Rel and RelA are members of the NF-kappaB family of transcription factors. They both have important roles in T cell activation. To discover where in the genome c-Rel and RelA bind and hence which genes they may directly target, we used ChIP-chip with EL4 cells stimulated with phorbol ester (PMA) and Ionomycin. We have identified regions in EL4 cells (background strain: C57BL/6N) activated for 2h or 8h by PMA and Ionomycin, that bind the transcription factors c-Rel and RelA.
Project description:c-Rel and RelA are members of the NF-kappaB family of transcription factors. They both have important roles in T cell activation. To discover where in the genome c-Rel and RelA bind and hence which genes they may directly target, we used ChIP-chip with EL4 cells stimulated with phorbol ester (PMA) and Ionomycin. We have identified regions in EL4 cells (background strain: C57BL/6N) activated for 2h or 8h by PMA and Ionomycin, that bind the transcription factors c-Rel and RelA. Immunoprecipitated samples from EL4 cells stimulated with PMA and ionomycin for 2 h and 8 h with antibodies against RelA or c-Rel respectively were used for ChIP-on-chip experiments. In addition, samples from total input and mock immunoprecipitation were used as controls. Biological triplicates were used.