Recent studies have demonstrated that upon encountering a pathogenic stimulus, robust metabolic rewiring of immune cells occurs. A switch away from oxidative phosphorylation to glycolysis, even in the presence of sufficient amounts of oxygen (akin the Warburg effect), is typically observed in activated innate and adaptive immune cells and is thought to accommodate adequate inflammatory responses. However, whether the Warburg effect is a general phenomenon applicable in human monocytes exposed to different pathogenic stimuli is unknown. Our results using human monocytes from healthy donors demonstrate that the Warburg effect only holds true for TLR4 activated cells. Although activation of other TLRs leads to an increase in glycolysis, no reduction or even an enhancement in oxidative phosphorylation is observed. Moreover, specific metabolic rewiring occurs in TLR4 vs. TLR2 stimulated cells characterized by altered gene expression profiles of pathways related to metabolism, changes in spare respiratory capacity of the cells and differential regulation of mitochondrial enzyme activity. Similarly, results from ex vivo and in vivo studies demonstrate metabolic rewiring of immune cells that is highly dependent on the type of pathogenic stimulus. Although the Warburg effect is observed in human monocytes after TLR4 activation, we propose that this typical metabolic response is not applicable to other inflammatory signalling routes including TLR2 in human monocytes. Instead, each pathogenic stimulus and subsequently activated inflammatory signalling cascade induces specific metabolic rewiring of the immune cell to accommodate an appropriate response.
Microbial stimulation of different Toll-like receptor signalling pathways induces diverse metabolic programmes in human monocytes.
Specimen part, Treatment, Subject
View SamplesMetformin, the most widely administered diabetes drug, has been proposed as a candidate for host directed therapy for tuberculosis although very little is known about its effects on human host responses to Mycobacterium tuberculosis. When added in vitro to PBMCs isolated from healthy non-diabetic volunteers, metformin increased glycolysis, inhibited the mTOR targets, strongly reduced M. tuberculosis induced production of TNF-alpha (-58%), IFN-gamma (-47%) and IL-beta (-20%), while increasing phagocytosis. In healthy subjects, in vivo metformin intake induced significant transcriptional changes in whole blood and isolated PBMCs, with substantial down-regulation of genes related to inflammation and the type 1 interferon response. Metformin intake also increased monocyte phagocytosis (by 1.5 to 2 fold) and ROS production (+20%). These results show that metformin in humans has a range of potentially beneficial effects on cellular metabolism, immune function and gene-transcriptional level, that affect innate host responses to M. tuberculosis. This underlines the importance of cellular metabolism for host immunity and supports a role for metformin as host-directed therapy for tuberculosis. Overall design: Peripheral Mononuclear Cells taken from 11 healthy donors, prior to administration of metformin and after 5 days of metformin. Samples were stimulated with Mycobacterium tuberculosis lysate or cultured unstimulated for 4 hours. Total 88 samples, with 11 clinical replicates.
Metformin Alters Human Host Responses to Mycobacterium tuberculosis in Healthy Subjects.
Specimen part, Disease, Disease stage, Treatment, Subject
View SamplesMetformin, the most widely administered diabetes drug, has been proposed as a candidate for host directed therapy for tuberculosis although very little is known about its effects on human host responses to Mycobacterium tuberculosis. When added in vitro to PBMCs isolated from healthy non-diabetic volunteers, metformin increased glycolysis, inhibited the mTOR targets, strongly reduced M. tuberculosis induced production of TNF-a (-58%), IFN-gamma (-47%) and IL-1ß (-20%), while increasing phagocytosis. In healthy subjects, in vivo metformin intake induced significant transcriptional changes in whole blood and isolated PBMCs, with substantial down-regulation of genes related to inflammation and the type 1 interferon response. Metformin intake also increased monocyte phagocytosis (by 1.5 to 2 fold) and ROS production (+20%). These results show that metformin in humans has a range of potentially beneficial effects on cellular metabolism, immune function and gene-transcriptional level, that affect innate host responses to M. tuberculosis. This underlines the importance of cellular metabolism for host immunity and supports a role for metformin as host-directed therapy for tuberculosis. Overall design: Ex vivo blood RNA samples analyzed from 11 healthy donors, prior to administration of metformin (control) and after 5 days of metformin (test). Total 22 samples, with 11 clinical replicates.
Metformin Alters Human Host Responses to Mycobacterium tuberculosis in Healthy Subjects.
Specimen part, Disease, Disease stage, Treatment, Subject
View SamplesThis dataset was used to benchmark the Virtual Inference of Protein-activity by Regulon Readout algorithm (VIPER). Despite recent advances in molecular profiling, proteome-wide assessment of protein activity in individual samples remains a highly elusive target. In stark contrast, protein activity quantitation is increasingly critical to the dissection of key regulatory processes and to the elucidation of biologically relevant mechanisms. Importantly, its value extends to the study of drug activity, as most small molecules inhibit activity of their cognate protein substrates without affecting the proteins or associated mRNAs abundance.
Functional characterization of somatic mutations in cancer using network-based inference of protein activity.
Specimen part, Cell line
View SamplesSchizophrenia (SZ) and autism spectrum disorders (ASD) are highly heritable neuropsychiatric/neurodevelopmental disorders, although environmental factors, such as maternal immune activation (MIA), play a role as well. Inflammatory cytokines appear to mediate the effects of MIA on neurogenesis and behavior in animal models. However, drugs and cytokines that trigger MIA can also induce a febrile reaction, which could have independent effects on neurogenesis through heat shock (HS)-regulated cellular stress pathways. However, this has not been well-studied. As a first step towards addressing the role of fever in MIA, we used a recently described model of human brain development in which induced pluripotent stem cells (iPSCs) differentiate into 3-dimensional neuronal aggregates that resemble a first trimester telencephalon. RNA-seq was carried out on aggregates that were heat shocked at 39oC for 24 hours, along with their control partners maintained at 37oC. Overall, 186 genes showed significant differences in expression following HS (p<0.05), including known HS-inducible genes, as expected, as well as those coding for NGFR and a number of SZ and ASD candidates, including SMARCA2, DPP10, ARNT2, AHI1 and ZNF804A. The degree to which the expression of these genes decrease or increase during HS is similar to that found in copy loss and copy gain CNVs, although the effects of HS are likely to be more transient. Overall design: RNA-seq was carried out on neuronal aggregates as described by Mariani et al. with slight modification (PMID:22761314). For the heat shock experiment, a group of 49 day old aggregates was placed in an incubator set at 39C for 24 hours, while control sets of aggregates were maintained at 37C. The incubator conditions were otherwise unchanged. After detaching the aggregates, total cellular RNA was isolated using the miRNeasy Kit (Qiagen) according to the manufacturer's protocol. Lastly, RNAseq profiles of HS and Control were compared
Heat shock alters the expression of schizophrenia and autism candidate genes in an induced pluripotent stem cell model of the human telencephalon.
No sample metadata fields
View SamplesBeyond the DNA sequence difference between humans and closely related apes, there are large differences in the environments that these species experience. One prominent example for this is diet. The human diet diverges from those of other primates in various aspects, such as having a high calorie and protein content, as well as being cooked. Here, we used a laboratory mouse model to identify gene expression differences related to dietary differences.
Human and chimpanzee gene expression differences replicated in mice fed different diets.
Sex, Age
View SamplesBeyond the DNA sequence difference between humans and closely related apes, there are large differences in the environments that these species experience. One prominent example for this is diet. The human diet diverges from those of other primates in various aspects, such as having a high calorie and protein content, as well as being cooked. Here, we used a laboratory mouse model to identify gene expression differences related to dietary differences.
Human and chimpanzee gene expression differences replicated in mice fed different diets.
Sex, Age
View SamplesDeletions at 15q11.2 have been established to increase risk for multiple neurodevelopmental disorders (NDDs) including schizophrenia and epilepsy, yet show variable expressivity between individuals. To investigate the potential role of CYFIP1, a gene within the locus, we carried out knockdown experiments in human neural progenitor cells derived from 15q11.2 neutral induced pluripotent stem cells. Transcriptional profiling and cellular assays support a prominent role for CYFIP1 in cytoskeletal remodeling across all lines examined. Validating the utility of this model for study of disease, genes implicated in schizophrenia and epilepsy but not other disorders or traits unrelated to the deletion, were enriched among mRNAs dysregulated following knockdown. Importantly, and consistent with the variable expressivity of 15q11.2 deletions, the magnitude of disease-related effects varied between donor lines. Towards mechanisms, FMRP targets and synaptic genes were overrepresented among dysregulated mRNAs and as such may contribute to the schizophrenia and epilepsy effects we observe. Further model validation, and new candidate epilepsy genes, comes from machine-learning analyses showing a striking similarity between a subset of dysregulated transcripts and well-established epilepsy genes. Results provide support for an important contribution of CYFIP1 in 15q11.2 mediated risk for NDDs and demonstrate that disease-related biological signatures are evident prior to neuronal differentiation. This new human model of disease will be useful in identifying compounds that could ameliorate outcomes in deletion carriers. Overall design: Investigation of CYFIP1 shRNA knockdown in three neural progenitor cell lines derived from induced pluripotent stem cells (3 control samples and 3 knockdown samples analyzed in each line)
Reduced CYFIP1 in Human Neural Progenitors Results in Dysregulation of Schizophrenia and Epilepsy Gene Networks.
No sample metadata fields
View SamplesThe goal of this project is to study transcriptome change by knocking down ZNF804A, a schizophrenia and bipolar disorder candidate gene, in early neurons derived from iPSCs. Overall design: Neural progenitor cells (NPCs) were developed from human induced pluripotent stem cells (iPSCs) and transduced by two independent shRNA vectors targeting ZNF804A, a schizophrenia and bipolar disorder candidate gene. After recovery and selection in puromycin, neuronal differentiation was induced. After 14 days, RNA was recovered and analyzed by RNA-seq. The expression profiles were compared with NPCs that were transduced with scrambled control vectors. This corresponds to controls 1-3 and KD 1-3, which was carried out on a male iPSC line. Scramble 1 and 2 and KD1 and 2 are technical replicates. Scrambled 3 and KD 3 were carried out on an independent NPC culture. For control 4 and KD4, neuronal differentiation was induced, and on day 10 the cells were transduced with the same ZNF804A KD and scrambled control vectors used for scrambled control 3 and KD3. In addition, this last set was carried out on a female iPSC line
ZNF804A Transcriptional Networks in Differentiating Neurons Derived from Induced Pluripotent Stem Cells of Human Origin.
No sample metadata fields
View SamplesMicroarray technologies allow the identification of large numbers of expression differences within and between species. Although environmental and physiological stimuli are clearly responsible for changes in the expression levels of many genes, it is not known whether the majority of changes of gene expression fixed during evolution between species and between various tissues within a species are caused by Darwinian selection or by stochastic processes. We find the following: (1) expression differences between species accumulate approximately linearly with time; (2) gene expression variation among individuals within a species correlates positively with expression divergence between species; (3) rates of expression divergence between species do not differ significantly between intact genes and expressed pseudogenes; (4) expression differences between brain regions within a species have accumulated approximately linearly with time since these regions emerged during evolution. These results suggest that the majority of expression differences observed between species are selectively neutral or nearly neutral and likely to be of little or no functional significance. Therefore, the identification of gene expression differences between species fixed by selection should be based on null hypotheses assuming functional neutrality. Furthermore, it may be possible to apply a molecular clock based on expression differences to infer the evolutionary history of tissues.
A neutral model of transcriptome evolution.
Sex, Age, Specimen part, Disease, Disease stage
View Samples