The alveolar type 1 (AT1) cell covers >95% of the gas exchange surface and is extremely thin to facilitate passive gas diffusion. The development of this highly specialized cell is poorly understood including fundamental questions regarding cell number and morphology. Using new molecular stereology and single cell imaging methods, we show that AT1 cells develop via a non-proliferative two-step process while maintaining proliferative potential. In the flattening step, AT1 cells remodel cell junctions and undergo molecular specification. In the folding step, AT1 cells are sculptured to match secondary septa formation, resulting in a single AT1 cell spanning multiple alveoli. AT1 cells grow in size by >10-fold, fueling most of the postnatal lung growth. Strikingly AT1 cells proliferate upon ectopic SOX2 expression and undergo stage-dependent cell fate reprogramming. These results contradict the traditional view of AT1 cells being terminally differentiated and provide insights to alveolar maturation. In this experiment, we conducted next-generation sequencing on flow-sorter AT1 cells isolated from mouse lungs ectopically expressing Sox2 under the control of the AT1-specific promoter Scnn1a versus control AT1 cells. Overall design: Two samples of Sox2-expressing AT1 cells versus two control AT1 samples.
The development and plasticity of alveolar type 1 cells.
Cell line, Subject
View SamplesThe study used two Drosophila melanogaster fly lines, Alstonville and Dahomey, which have mitochondrial DNA variants but otherwise similar genomes. Female third instar larvae from both lines were fed on two diets, one with a 1:2 protein:carbohydrate ratio and the other with a 1:16 ratio. RNA was extracted and profiled by RNA-seq. Samples were sequenced on an Illumina Hiseq 2000 sequencer at the Ramaciotti Centre for Genomics, Sydney, Australia to produce 100bp paired end reads. At least 80 million read pairs were generated per sample. Overall design: Four independent replicates were obtained for each mitotype-diet combination.
Genotype to phenotype: Diet-by-mitochondrial DNA haplotype interactions drive metabolic flexibility and organismal fitness.
Subject
View SamplesWe used microarrays to provide a transcriptomic signature of different types of cholestasis evoked by 3 different drugs and obstructive surgery
Robustness testing and optimization of an adverse outcome pathway on cholestatic liver injury.
Specimen part, Cell line, Treatment
View SamplesG protein-coupled receptor kinase 2 (GRK2) has emerged as a key regulator of cardiac function and myocardial structure. Cardiac GRK2 is increased in heart failure and ischemia in humans, whereas genetic inhibition of GRK2 is cardioprotective in animal models of these pathologies. However, the mechanistic basis underlying these effects are not fully understood. We have used adult GRK2 hemizygous mice (GRK2+/-) as a model to assess the effects of a sustained systemic inhibition of GRK2 in heart tissue with age.
Downregulation of G protein-coupled receptor kinase 2 levels enhances cardiac insulin sensitivity and switches on cardioprotective gene expression patterns.
Specimen part
View SamplesUnveiling the regulatory pathways maintaining hepatic stellate cells (HSC) in a quiescent (q) phenotype is essential to develop new therapeutic strategies to treat fibrogenic diseases. To uncover the miRNA-mRNAs regulatory interactions in qHSCs, HSCs were FACS-sorted from healthy livers and activated HSCs were generated in vitro. MiRNA Taqman array analysis showed HSCs expressed a low number of miRNA, from which 46 were down-regulated and 212 up-regulated upon activation. Computational integration of miRNA and gene expression profiles revealed that 66% of qHSCs miRNAs correlated with more than 6 altered targeted mRNAs (17,2810,7 targets/miRNA), whereas aHSC-associated miRNAs had an average of 1,49 targeted genes. Interestingly, interaction networks generated by miRNA-targeted genes in qHSCs were associated with key HSCs activation processes. Next, selected miRNAs were validated in healthy and cirrhotic human livers and miR-192 was chosen for functional analysis. Down-regulation of miR-192 in HSC was found to be an early event during fibrosis progression in mouse models of liver injury. Moreover, mimic assays for miR-192 in HSCs revealed its role in HSC activation, proliferation and migration. Together, these results uncover the importance of miRNAs in the maintenance of qHSC phenotype and form the basis for understanding the regulatory networks in HSCs.
Integrative miRNA and Gene Expression Profiling Analysis of Human Quiescent Hepatic Stellate Cells.
Specimen part
View SamplesThis SuperSeries is composed of the SubSeries listed below.
Aberrant epigenome in iPSC-derived dopaminergic neurons from Parkinson's disease patients.
Sex, Specimen part, Disease, Disease stage, Subject
View SamplesWe analysed the RNA profile of IPSC-derived dopaminergic neurons from idiophatic and genetic form (LRRK2) of Parkinsons disease (PD). Both, idiopathic and genetic form of the disease show similar expression alterations and were merged in one whole PD group. We found 437 differentially expressed genes (DEGs) in the PD group as a whole. Up-regulated DEGs (n=254) encompassed genes involved in neural functions and transcription factor functions whereas down-regulated DEGs (n=183) affected basic homeostasis. These data point towards the presence of gene - and also protein - expression changes in DAn from PD patients which co-occur simultaneously along with DNA methylation changes.
Aberrant epigenome in iPSC-derived dopaminergic neurons from Parkinson's disease patients.
Sex, Specimen part, Disease, Disease stage
View SamplesMicroglia constitutes a diverse population of cells that present a broad spectrum of responses when they become activated. Here, microglial status was studied under steady-state conditions from different brain regions involved in neurodegenerative diseases. Under basal conditions, midbrain microglia showed an immune-alert state not observed in striatum. Unique subpopulations of microglia expressing TLR4 and MHC-II with antigen presenting properties, and a higher proportion of infiltrating CD4+ T cells were identified in the midbrain. These results highlight that the inflammatory tone is context-dependent and reveal the unique properties of the midbrain related to the interaction with the immune system. Overall design: Analysis of two cohorts of control animals
Midbrain microglia mediate a specific immunosuppressive response under inflammatory conditions.
Age, Cell line, Subject
View SamplesGuillain-Barré syndrome (GBS) is an immune-mediated peripheral neuropathy that debilitates the voluntary and autonomous response of the patient. In this study the transcriptome of peripheral blood mononuclear cells from a GBS patient and her healthy twin were compared to discover possible correlates of disease progression and recovery. Overall design: Blood samples were collected simultaneously from the Guillain-Barré patient (A) and from her control healthy twin (B) at three different time points during disease progression from hospitalization in the intensive care unit (T1), passing to intermediate care (T2), and at conclusion of locomotion rehabilitation program when the patient was close to abandon the hospital (T3).
Expression of Early Growth Response Gene-2 and Regulated Cytokines Correlates with Recovery from Guillain-Barré Syndrome.
No sample metadata fields
View SamplesThe combination of defined factors with small molecules targeting epigenetic factors is a strategy that has been shown to enhance optimal derivation of human iPSCs and could be used for therapeutic and regenerative medicine applications. In this study, we showed that a new first-in-class dual G9a/DNMT inhibitor CM272 compound improves the standard four-factor reprogramming efficiency of human fibroblast. The use of CM272 facilitates the generation of iPSC with only two factors, OCT4 and SOX2, allowing the removal of potentially oncogenic factors such as cMYC or KLF4. Taking a closer look at the early events occurring during cell reprogramming we demonstrated that treatment with our G9a/DNMT dual inhibitor induces heterochromatin relaxation, facilitates the engagement of OCT4 and SOX2 transcription factors to the genome and promotes mesenchymal to epithelial transition during cell reprogramming. Thus, the use of this new G9a/DNMT dual inhibitor compound may represent an interesting alternative for improving cell reprogramming.
Reversible dual inhibitor against G9a and DNMT1 improves human iPSC derivation enhancing MET and facilitating transcription factor engagement to the genome.
Sex, Specimen part, Disease, Cell line
View Samples