This SuperSeries is composed of the SubSeries listed below.
Transcriptome-based network analysis reveals a spectrum model of human macrophage activation.
Specimen part, Subject, Time
View SamplesMacrophage activation is associated with profound transcriptional reprogramming. Although much progress has been made in the understanding of macrophage activation, polarization and function, the transcriptional programs regulating these processes remain poorly characterized. We stimulated human macrophages with diverse activation signals, acquiring a dataset of 299 macrophage transcriptomes. Analysis of this dataset revealed a spectrum of macrophage activation states extending the current M1 versus M2-polarization model. Network analyses identified central transcriptional regulators associated with all macrophage activation complemented by regulators related to stimulus-specific programs. Applying these transcriptional programs to human alveolar macrophages from smokers and patients with chronic obstructive pulmonary disease (COPD) revealed an unexpected loss of inflammatory signatures in COPD patients. Finally, by integrating murine data from the ImmGen project we propose a refined, activation-independent core signature for human and murine macrophages. This resource serves as a framework for future research into regulation of macrophage activation in health and disease.
Transcriptome-based network analysis reveals a spectrum model of human macrophage activation.
Subject, Time
View SamplesThis SuperSeries is composed of the SubSeries listed below.
Cellular Differentiation of Human Monocytes Is Regulated by Time-Dependent Interleukin-4 Signaling and the Transcriptional Regulator NCOR2.
Specimen part, Subject
View SamplesRegulatory T (Treg) cells are involved in self tolerance, immune homeostasis, prevention of autoimmunity, and suppression of immunity to pathogens or tumours. The forkhead transcription factor FOXP3 is essential for Treg cell development and function as mutations in FOXP3 cause severe autoimmunity in mice and humans. However, the FOXP3-dependent molecular mechanisms leading to this severe phenotype are not well understood. Here we introduce the chromatin remodelling enzyme SATB1 (special AT-rich sequence-binding protein-1) as an important target gene of FOXP3. So far, SATB1 has been associated with normal thymic T-cell development, peripheral T-cell homeostasis, TH1/TH2 polarization, and reprogramming of gene expression. In natural and induced murine and human FOXP3+ Treg cells SATB1 expression is significantly reduced. While there is no differential epigenetic regulation of the SATB1 locus between Treg and Teffector cells, FOXP3 reduces SATB1 expression directly as a transcriptional repressor at the SATB1 locus and indirectly via miR-155 induction, which specifically binds to the 3UTR of the SATB1 mRNA. Reduced SATB1 expression in FOXP3+ cells achieved either by overexpression or induction of FOXP3 is linked to significant reduction in TH1 and TH2 cytokines, while loss of FOXP3 function either by knock down or genetic mutation leads to significant upregulation of SATB1 and subsequent cytokine production. Alltogether, these findings demonstrate that reduced SATB1 expression in Treg cells is necessary for maintenance of a Treg-cell phenotype in vitro and in vivo and places SATB1-mediated T cell-specific modulation of global chromatin remodelling central during the decision process between effector and regulatory T-cell function.
Repression of the genome organizer SATB1 in regulatory T cells is required for suppressive function and inhibition of effector differentiation.
Specimen part, Disease, Disease stage, Treatment
View SamplesWhole transcriptome profiling (Illumina Microarray) of human ex vivo lymphocytes and monocytes, as well as of human monocyte-derived cells generated in vitro by activating CD14+ monocytes with MCSF, GMCSF or the combination of GMCSF and IL4
Cellular Differentiation of Human Monocytes Is Regulated by Time-Dependent Interleukin-4 Signaling and the Transcriptional Regulator NCOR2.
Specimen part
View SamplesBased on studies in knockout mice, several inhibitory factors such as TGF-beta, IL-10, or CTLA-4 have been implicated as gate keepers of adaptive immune responses. Lack of these inhibitory molecules leads to massive inflammatory responses mainly mediated by activated T cells. In humans, the integration of these inhibitory signals for keeping T cells at a resting state is less well understood. To elucidate this regulatory network we assessed early genome-wide transcriptional changes during serum deprivation in human mature CD4+ T cells. The most striking observation was a "TGF-beta loss signature" defined by downregulation of many known TGF-beta target genes. Moreover, numerous novel TGF-beta target genes were identified that are under the suppressive control of TGF-beta. Expression of these genes was upregulated once TGF-beta signaling was lost during serum deprivation and again suppressed upon TGF-beta reconstitution. Constitutive TGF-beta signaling was corroborated by demonstrating phosphorylated SMAD2/3 in resting human CD4+ T cells in situ, which were dephosphorylated during serum deprivation and re-phosphorylated by minute amounts of TGF-beta. Loss of TGF-beta signaling was particularly important for T cell proliferation induced by low-level T cell receptor and costimulatory signals. We suggest TGF-beta to be the most prominent factor actively keeping human CD4+ T cells at a resting state.
Human resting CD4+ T cells are constitutively inhibited by TGF beta under steady-state conditions.
No sample metadata fields
View SamplesBackground: Development of target specific therapeutics greatly benefits from simultaneous identification of biomarkers to determine aspects of bioactivity, drug safety and efficacy or even treatment outcome. This is particularly important when targeting pleiotropic factors such as the TGFbeta system. TGFbeta has become a prime target for cancer therapeutics since inhibition of TGFbeta signaling simultaneously attacks the tumor and its microenvironment. Methods: Here we introduce blood transcriptomics followed by a defined set of validation assays as a promising approach to identify novel biomarkers for monitoring TGFbeta therapy. Findings: Our initial genome-wide analysis of transcription in peripheral blood revealed 12 candidate genes specifically regulated in peripheral blood by the TGFbeta receptor I kinase inhibitor LY2109761. In subsequent in vitro and in vivo molecular and immunological analyses, the combined monitoring of gene regulation of three genes, namely TMEPAI, OCIAD2, and SMAD7 was established as novel biomarkers for anti-TGFbeta based therapies. Interpretation: Overall, the proposed algorithm of biomarker identification is easily adapted towards other drug candidates for which gene regulation can be established in peripheral blood.
Application of T cell-based transcriptomics to identify three candidate biomarkers for monitoring anti-TGFbetaR therapy.
Specimen part
View SamplesThe alarmins myeloid-related protein (MRP) 8 and MRP14 are the dominant cytoplasmic proteins in phagocytes. After release by activated phagocytes extracellular MRP8/MRP14 complexes promote inflammation in many diseases, including infections, allergies, autoimmune diseases, rheumatoid arthritis or inflammatory bowel disease. As receptors for the pro-inflammatory effects of human MRP8, the active component of the MRP8/MRP14-complex, Toll-like receptor (TLR) 4 and the multi-ligand receptor of advanced glycation end products (RAGE) are controversial discussed. Using a comparative bioinformatics analysis between genome-wide response patterns of monocytes to MRP8, endotoxin and different cytokines we demonstrated a dominant role of TLR4 during MRP8-mediated phagocyte activation. The relevance of this signaling pathway could be confirmed in independent cell models for TLR4 and RAGE dependent signaling in mouse and man. In addition to well-known proinflammatory functions of MRP8 our systems biology approach unraveled a novel anti-apoptotic effect of MRP8 on monocytes which was confirmed in independent functional experiments. Our data define the dominance of the TLR4-MRP8 axis in activation of human phagocytes which represents a novel attractive target for modulation of overwhelming innate immune responses.
Transcriptome assessment reveals a dominant role for TLR4 in the activation of human monocytes by the alarmin MRP8.
Specimen part, Treatment
View SamplesRegulatory T (Treg) cells are characterized by the forkhead transcription factor FOXP3. Mutations in FOXP3 cause autoimmunity in mice and humans. Here, Treg cells as well as conventional T cells were isolated from B-CLL patients and analyzed by global gene expression analysis in order to identify biological differences in Treg cells of CLL patients.
No associated publication
Specimen part, Disease, Disease stage, Treatment
View SamplesMyeloid dendritic cells (DC) and macrophages play an important role in pathogen sensing and antimicrobial defense. Recently we demonstrated that infection of human DC with intracellular bacterium Listeria monocytogenes (L.monocytogenes) leads to the induction of the immunoinhibitory enzyme indoleamine 2,3-dioxygenase (Popov et al., J Clin Invest, 2006), while in the previous studies L.monocytogenes infection was associated with a rather stimulatory DC phenotype. To clarify this discrepancy we performed comparative microarray analysis of immature mo-DC (immDC), mature stimulatory mo-DC (matDC) and mature inhibitory DC either stimulated with prostaglandin E2 (PGE2-DC) or infected with L.monocytogenes (infDC). Studying infection of human myeloid DC with Listeria monocytogenes, we found out, that infected DC are modified by the pathogen to express multiple inhibitory molecules, including indoleamine 2,3-dioxygenase (IDO), cyclooxygenase-2, interleukin 10 and CD25, which acts on DC as IL-2 scavenger. All these inhibitory molecules, expressed on regulatory DC (DCreg), are strictly TNF-dependent and are in concert suppressing T-cell responses. Moreover, only DCreg can efficiently control the number of intracellular listeria, mostly by IDO-mediated mechanisms and by other factors, remaining to be identified. Analyzing publicly acessible data of transcriptional changes in DC and macrophages, infected by various pathogens and parasites (GEO, GSE360), we noticed that infection of these cells with Mycobacterium tuberculosis causes transcriptional response, comparable with the one caused by listeria in human DC. In fact, granuloma in tuberculosis and listeriosis in vivo are enriched for myeloid DC and macrophages characterized by regulatory phenotype.
Infection of myeloid dendritic cells with Listeria monocytogenes leads to the suppression of T cell function by multiple inhibitory mechanisms.
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