Transcriptome analysis of Blimp1-sufficient (Ctrl) and Blimp1-deficient (CKO) CD4+ Foxp3+ regulatory (Treg) and Foxp3- effector (Teff) T cells
ABSTRACT: Comparative analysis of regulation of gene expression by Blimp1 in regulatory and effector CD4+ T cells. The hypothesis tested in the present study was that Blimp1 differentially regualte gene expression in different T cell subsets. Results provide important information of mechanisms underlying regulation of gene expression by Blimp1 in T cells Overall design: Allotype marked Foxp3GFP reporter Blimp1-sufficient and Blimp1-deficient naïve (CD4+CD44low) T cells were transferred at a 1:1 ratio to RAG1-/- mice. Six-eight weeks later cells were sorted based on Foxp3, CD4 and allotype marker expression, generating 4 different groups (Blimp1 sufficient and Blimp1-defficent regulatory (CD4+Foxp3+) and Blimp1-sufficient and Blimp1-deficient effector (CD4+Foxp3-) T cells
Project description:Foxp3+ regulatory T (Treg) cells restrict immune pathology in inflamed tissues; however, an inflammatory environment presents a threat to Treg cell identity and function. We here establish a transcriptional signature of central nervous system (CNS) Treg cells that accumulate during experimental autoimmune encephalitis (EAE) and identify a pathway that maintains Treg cell function and identity during severe inflammation. This pathway was dependent on the transcriptional regulator Blimp1, which prevented dismantling of Foxp3 expression and "toxic" gain-of-function of Treg cells in the inflamed CNS. Blimp1 negatively regulated IL-6- and STAT3-mediated methylation of Treg cell-specific conserved non-coding sequence 2 (CNS2) in the Foxp3 locus. Consequently, CNS2 was heavily methylated when Blimp1 was ablated, leading to loss of Foxp3 expression and severe disease. These findings identify a Blimp1-dependent epigenetic pathway that preserves Treg cell stability in inflamed non-lymphoid tissues. Overall design: Comparison of DNA accessibility by Omni-ATAC-seq in conventional T cells (Tconv) and regulatory T cells (Treg) of wild-type vs Treg conditional Blimp1 deficient mice isolated from the CNS and spleen at the peak of experimental autoimmune encephalitis (EAE). All samples were FACS sorted ex vivo according to CD4+Foxp3(GFP)- = Tconv and CD4+Foxp3(GFP)+ = Treg from mixed bone morrow chimeras with congenically marked wild-type (CD45.1) and Treg conditional Blimp1 KO compartments (CD45.2).
Project description:To understand the differentiation of effector Tregs in more detail, we have performed transcriptional profiling of central Tregs and effector Tregs, based on Blimp1 expression. We performed RNA-sequencing of Foxp3+ regulatory T cells, comparing Blimp1/GFP+ and Blimp1/GFP- cells Three biologically independent samples for each condition were sequenced (condition 1: CD4+ CD25high Blimp1/GFP+; condition 2: CD4+ CD25high Blimp1/GFP-); cells were sorted from pooled spleens and lymphnodes of Blimp1/GFP reporter mice
Project description:Regulatory T cells have been shown to adopt a catabolic metabolic programme with increased capacity for fatty acid oxidation fuelled oxidative phosphorylation (OXPHOS). The role of Foxp3 in this metabolic shift is poorly understood. Here we show that Foxp3 was sufficient to induce a significant increase in the spare respiratory capacity of the cell, the extra OXPHOS capacity available to a cell to increased demands on energy in response to work. Foxp3-expressing cells were enhanced in their ability to utilise palmitate for respiration and in addition the activity of electron transport complexes I, II and IV were enhanced following Foxp3 expression. ATP was secreted by both T effector and regulatory T cells and was reduced by mitochondrial respiration inhibitors. Thus Foxp3 imparts a selective advantage in ATP generation capacity to the cell and may exploit this as a source of adenosine for functional immunomodulation. In order to explore possible mechanisms for these differences in metabolism we conducted a comparative quantitative proteomics study to compare the contribution of TGFβ and the transcription factor Foxp3 to the Treg proteome. We used quantitative mass spectrometry to examine differences between proteomes of nuclear and cytoplasmic Foxp3-containing T cells and Foxp3 positive iTreg and Foxp3 negative activated CD4 T cells in addition to human peripheral blood natural Treg. Gene set enrichment analysis of our proteomic datasets demonstrated that Foxp3 drives a significant up regulation of several members of the mitochondrial electron transport chain.
Project description:We previously found that NF-kB inducing kinase (NIK) overexpression in T cells via CD4 promoter driven transgene induction caused lethal autoimmunity in mice. Autoimmunity was associated with increased conventional T cell effector function and decreased regulatory T cell (Foxp3+CD4+) suppression. The goal in this study was to elucidate global transcriptional changes in Foxp3+CD4+ and Foxp3-CD4+ T cells intrinsically caused by chronic NIK overexpression in these cell types. Overall design: Total RNA from FACS-sorted NIKtg and WT Foxp3RFP+CD4+ and Foxp3RFP-CD4+ harvested from NIKtg/CD4Cre/Foxp3RFP + WT/Thy1.1/Foxp3RFP mixed bone marrow chimeric mice, >8 weeks after bone marrow reconstitution.
Project description:We previously found that NF-kB inducing kinase (NIK) overexpression in T cells via CD4 promoter driven transgene induction caused lethal autoimmunity in mice. Autoimmunity was associated with increased conventional T cell effector function and decreased regulatory T cell (Foxp3+CD4+) suppression. The goal in this study was to elucidate global transcriptional changes in Foxp3+CD4+ and Foxp3-CD4+ T cells intrinsically caused by chronic NIK overexpression in these cell types. Total RNA from FACS-sorted NIKtg and WT Foxp3RFP+CD4+ and Foxp3RFP-CD4+ harvested from NIKtg/CD4Cre/Foxp3RFP + WT/Thy1.1/Foxp3RFP mixed bone marrow chimeric mice, >8 weeks after bone marrow reconstitution. Overall design: Fanny,Polesso
Project description:We grouped Foxp3+ cells from Foxp3 Timer reporter mice into Blue1, Blue2, Red1, and Red2, and sorted these cells according to their Timer fluorescence expression, and analysed the transcriptional profiles of those cells, comparing them with those of effector and naive T cells using RNA-seq. Foxp3 Timer reporter mice were sensitised by a hapten, and 5 days later, the draining LNs of the skin were analysed. Overall design: Foxp3Timer mice were sensitised with application of 3% Oxazolone to abdominal skin. 5 days later inguinal and axillary Lymph nodes were harvested and pooled within the 3 biological replicates. The following populations of T-cells were sorted from each mouse: 1. CD44loFoxp3Timer- (Naïve T-cells) 2. CD44hiFoxp3Timer- (Activated effector T-cells) 3. CD4+ Pers1 (BL1, persistent Foxp3 transcription) 4. CD4+ Pers2 (BL2, persistent Foxp3 transcription) 5. CD4+ PAt (RD1, quiescent Treg) 6. CD4+ Arrested (RD2, arrested Foxp3 transcription) RNA was extracted and RNA-seq data obtained, generating a triplicate dataset for the 6 T-cell populations.
Project description:Investigation of the role of FOXP3 in CD4+ T effector cells. FOXP3 is transiently upregulated in T effector cells under activation. This temporary expression in Teff cells is insufficient to suppress expression of reported targets of FOXP3 repressor activity. The role of FOXP3 in T effector cells remains unclear. We used microarray analysis to detail the differentially expressed genes between FOXP3 wild type and 2T>C(mut) clones and identified classes of up-regulated or down-regulated genes based upon FOXP3 expression. We used T effector cells from one IPEX disease carrier mother that consist of a mixed population ofFOXP3 wild type and 2T>C(mut) clones. We activated them using anti-CD3, anti-CD28. We compareFOXP3 wild type and 2T>Cl clones at different stages: resting phase and activated phase at 72hrs.
Project description:Analysis of the transcriptional correlates of FOXP3 expression in suppressive and non-suppressive primary human Treg cell clones. Individual CD4+CD25High or Cd4+CD25- T cells were isolated from human PBMCs and expanded in vitro. After 3 weeks of expansion, individual clones were analysed for FOXP3 expression and in vitro suppressive activity against freshly sorted allogeneic effector T cells. This study analyses the total RNA isolated from FOXP3+ clones with suppressive potency to their non-suppressive counterparts. The resutls of this study should provide insights into the molecular pathways linking FOXP3 expression to distinct aspects of Treg phenotype and function. Total RNA obtained from individual clones of primary human regulatory and effector CD4+T cells.
Project description:CD4+Foxp3+ regulatory T cells (Treg) are essential for immune homeostasis and maintenance of self-tolerance. They are produced in the thymus and also generated de novo in the periphery in a TGFB dependent manner. Foxp3+ Treg are also required to achieve tolerance to transplanted tissues when induced by co-receptor or costimulation blockade. Using TCR transgenic mice to avoid issues of autoimmune pathology we show that Foxp3 expression is necessary and sufficient for tissue tolerance by coreceptor blockade. Moreover, the known need in tolerance induction for TGFB signalling to T cells, can wholly be explained by its role in induction of Foxp3, as such signalling proved dispensable for the suppressive process. We analysed the relative contribution of TGFB and Foxp3 on the transcriptome of TGFB induced Treg. TGFB elicited a large set of downregulated signature genes. The number of genes uniquely modulated due to the influence of Foxp3 alone was surprisingly limited. Retroviral conditional Foxp3 expression proved sufficient to confer transplant-suppressive potency on CD4+ T cells, and was lost once nuclear Foxp3 expression was extinguished. Thus despite the large genetic influence of TGFB exposure on iTreg the crucial Foxp3 influenced signature independent of TGFB is small. These data support a dual role for TGFB and Foxp3 in induced tolerance, where TGFB stimulates Foxp3 expression whose sustained expression is associated with acquisition of tolerance 21 samples were analyzed. 5 replicates of Marilyn.Foxp3hCD2 activated (HY)(Untreated) and TGFB-induced (HYT) cells sorted as CD4+hCD2+ and CD4+hCD2- and 3 replicates of Marilyn.Foxp3-/- activated and TGFβ-experienced (but Foxp3-) cells sorted as CD4+CD2. Pairwise comparisons were generated for the Marilyn Foxp3hCD2 UT versus TGFB induced populations and also for the Marilyn Foxp3-/- UT versus the TGFB experienced cells sorted as CD4+CD2