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.
PLAU inferred from a correlation network is critical for suppressor function of regulatory T cells.
Specimen part
View SamplesGlioblastoma (GBM) patient-derived orthotopic xenografts (PDOXs) were derived from organotypic spheroids obtained from patient tumor samples. To detect whether gene expression profiles of GBM patient tumors are retained in PDOXs, we performed genome-wide transcript analysis by human-specific microarrays . In parallel, we analyzed GBM cell cultures and corresponding intracranial xenografts from stem-like (NCH421k, NCH644) and adherent GBM cell lines (U87, U251). PDOXs show a better transcriptomic resemblance with patient tumors than other preclinical models. The major difference is largely explained by the depletion of human-derived non-malignant cells.
Patient-derived organoids and orthotopic xenografts of primary and recurrent gliomas represent relevant patient avatars for precision oncology.
Specimen part, Disease
View SamplesWe performed high-time-resolution (HTR) transcriptome analyses of Pseudomonas aeruginosa PAO1 (PA) in a continuous cultivation system during the transition from high oxygen tension to low oxygen tension (HLOT) and the reversed transition from low to high oxygen tension (LHOT). From those genes responsive to both transient conditions, we identified 85 essential oxygen-availability responsive genes (EORGs), including the expected ones (arcDABC) encoding enzymes for arginine fermentation. We then predicted a highly accurate regulatory network for the EORGs of PA by integrating information from binding motif searching, literature and inverted HTR datasets.
No associated publication
Treatment, Time
View SamplesWe sought to obtain gene signature specific of high oxidative phsophorylation function.
Chemotherapy-Resistant Human Acute Myeloid Leukemia Cells Are Not Enriched for Leukemic Stem Cells but Require Oxidative Metabolism.
Cell line, Treatment
View SamplesThe zebrafish has the capacity to regenerate its heart after severe injury. While the function of a few genes during this process has been studied, we are far from fully understanding how genes interact to coordinate heart regeneration. To enable systematic insights into this phenomenon, we generated and integrated a dynamic co-expression network of heart regeneration in the zebrafish and linked systems-level properties to the underlying molecular events. Across multiple post-injury time points, the network displays topological attributes of biological relevance. We show that regeneration steps are mediated by modules of transcriptionally coordinated genes, and by genes acting as network hubs. We also established direct associations between hubs and validated drivers of heart regeneration with murine and human orthologs. The resulting models and interactive analysis tools are available at http://infused.vital-it.ch. Using a worked example, we demonstrate the usefulness of this unique open resource for hypothesis generation and in silico screening for genes involved in heart regeneration.
Analysis of the dynamic co-expression network of heart regeneration in the zebrafish.
Specimen part
View SamplesIt has been hypothesized that chemotherapy resistant human acute myeloid leukemia (AML) cells are enriched in an immature phenotype, cellular quiescence and leukemic initiating cells (LICs). However, these hypotheses have never been validated completely in vivo. We have developed a physiologically relevant chemotherapeutic approach with cytosine arabinoside AraC using patient-derived xenograft (PDX) models. AraC-treated AML cells are not consistently enriched for either immature cells or quiescent cells. AraC treatment does not enrich for LICs as measured by limiting dilution in secondary transplantations. Rather chemotherapy resistant cells in vivo have high levels of reactive oxygen species (ROS) and a gene signature consistent with oxidative phosphorylation (OXPHOS). Treatment of human HIGH OXPHOS but not LOW OXPHOS AML cell lines showed chemotherapy resistance in vivo, showing that essential mitochondrial functions make significant contributions to AraC resistance in AML. Accordingly, targeting mitochondrial OXPHOS metabolism through the inhibition of mitochondrial protein synthesis, the electron transfer chain or fatty acid oxidation induced an energetic shift towards LOW OXPHOS and strongly enhanced anti-leukemic effects of AraC in AML cells. These results demonstrate that chemotherapy resistance in AML is not necessarily associated with stemness but is highly dependent on a distinct oxidative metabolism, and that the HIGH OXPHOS gene signature is a robust hallmark of the AraC response in PDX and a promising therapeutic avenue to treat AML residual disease.
Chemotherapy-Resistant Human Acute Myeloid Leukemia Cells Are Not Enriched for Leukemic Stem Cells but Require Oxidative Metabolism.
Specimen part, Disease
View SamplesIt has been hypothesized that chemotherapy resistant human acute myeloid leukemia (AML) cells are enriched in an immature phenotype, cellular quiescence and leukemic initiating cells (LICs). However, these hypotheses have never been validated completely in vivo. We have developed a physiologically relevant chemotherapeutic approach with cytosine arabinoside AraC using patient-derived xenograft (PDX) models. AraC-treated AML cells are not consistently enriched for either immature cells or quiescent cells. AraC treatment does not enrich for LICs as measured by limiting dilution in secondary transplantations. Rather chemotherapy resistant cells in vivo have high levels of reactive oxygen species (ROS) and a gene signature consistent with oxidative phosphorylation (OXPHOS). Treatment of human HIGH OXPHOS but not LOW OXPHOS AML cell lines showed chemotherapy resistance in vivo, showing that essential mitochondrial functions make significant contributions to AraC resistance in AML. Accordingly, targeting mitochondrial OXPHOS metabolism through the inhibition of mitochondrial protein synthesis, the electron transfer chain or fatty acid oxidation induced an energetic shift towards LOW OXPHOS and strongly enhanced anti-leukemic effects of AraC in AML cells. These results demonstrate that chemotherapy resistance in AML is not necessarily associated with stemness but is highly dependent on a distinct oxidative metabolism, and that the HIGH OXPHOS gene signature is a robust hallmark of the AraC response in PDX and a promising therapeutic avenue to treat AML residual disease.
Chemotherapy-Resistant Human Acute Myeloid Leukemia Cells Are Not Enriched for Leukemic Stem Cells but Require Oxidative Metabolism.
Specimen part, Disease, Treatment, Subject
View SamplesWe compared gene expression profiles of a human CD4+ T-cell line 24 h after infection with a cell line of the same origin permanently releasing SIVmac251/32H. A new knowledge-based-network approach (Inter-Chain-Finder) was used to identify subnetworks leading to resistance to SIV-induced cell death. Notably, the method can identify not only differentially-expressed key hub genes but also non-differentially expressed, critical, hidden regulators.
Identification of molecular sub-networks associated with cell survival in a chronically SIVmac-infected human CD4+ T cell line.
Disease, Disease stage
View SamplesParkinsons disease (PD) has a neuro-developmental component with multiple genetic predispositions. The most prevalent mutation, LRRK2-G2019S is linked to familial and sporadic PD. Based on the multiple origins of PD and the incomplete penetrance of LRRK2-G2019S, we hypothesize that modifiers in the patient genetic background act as susceptibility factors for developing PD. To assess the developmental component of LRRK2-G2019S pathogenesis, we used 19 human iPSC-derived neuroepithelial stem cell lines (NESCs). Isogenic controls distinguish between LRRK2-G2019S dependent and independent cellular phenotypes. LRRK2-G2019S patient and healthy mutagenized lines showed altered NESC self-renewal. Within patients, phenotypes were only partly LRRK2-G2019S dependent, suggesting Parkinsons disease (PD) has a neuro-developmental component with multiple genetic predispositions. The most prevalent mutation, LRRK2-G2019S is linked to familial and sporadic PD. Based on the multiple origins of PD and the incomplete penetrance of LRRK2-G2019S, we hypothesize that modifiers in the patient genetic background act as susceptibility factors for developing PD. To assess the developmental component of LRRK2-G2019S pathogenesis, we used 19 human iPSC-derived neuroepithelial stem cell lines (NESCs).
No associated publication
No sample metadata fields
View SamplesTwo human acute lymphoblastic leukemia cell lines (Molt-4 and CCRF-CEM) were treated with direct (A-769662) and indirect (AICAR) AMPK activators. Molt-4 and CCRF-CEM cells were obtained from ATCC (CRL-1582 and CCL-119). Control samples were used for the analysis of metabolic differences between cell lines. Therefore the data was analyzed in combination with, metabolomic data, and the genome-scale reconstruction of human metabolism. For experiments cells were grown in serum-free medium containing DMSO (0.67%) at a cell concentration of 5 x 105 cells/mL.
Prediction of intracellular metabolic states from extracellular metabolomic data.
Cell line, Treatment
View Samples