The in vitro test battery of the European research consortium ESNATS (novel stem cell-based test systems) has been used to screen for potential human developmental toxicants. As part of this effort, the migration of neural crest (MINC) assay has been used to evaluate chemical effects on neural crest function. It identified some drug-like compounds in addition to known environmental toxicants. The hits included the HSP90 inhibitor geldanamycin, the chemotherapeutic arsenic trioxide, the flame-retardant PBDE-99, the pesticide triadimefon and the histone deacetylase inhibitors valproic acid and trichostatin A. Transcriptome changes triggered by these substances in human neural crest cells were recorded and analysed here to answer three questions: (1) can toxicants be individually identified based on their transcript profile; (2) how can the toxicity pattern reflected by transcript changes be compacted/ dimensionality-reduced for practical regulatory use; (3) how can a reduced set of biomarkers be selected for large-scale follow up? Transcript profiling allowed clear separation of different toxicants and the identification of toxicant types in a blinded test study. We also developed a diagrammatic system to visualize and compare toxicity patterns of a group of chemicals by giving a quantitative overview of altered superordinate biological processes (e.g. activation of KEGG pathways or overrepresentation of gene ontology terms). The transcript data were mined for potential markers of toxicity, and 39 transcripts were selected to either indicate general developmental toxicity or distinguish compounds with different modes-of-action in read-across. In summary, we found inclusion of transcriptome data to largely increase the information from the MINC phenotypic test.
Identification of transcriptome signatures and biomarkers specific for potential developmental toxicants inhibiting human neural crest cell migration.
Sex, Specimen part
View SamplesSafety sciences and the identification chemical hazard have been seen as one of the most immediate practical applications of human pluripotent stem cell technology. Protocols for the generation of many desirable human cell types have been developed, but optimization of neuronal models for toxicological use has been astonishingly slow, and the wide, clinically- important field of peripheral neurotoxicity is still largely unexplored. Here, a 2-step protocol to generate large lots of identical peripheral human neuronal precursors was characterized and adapted to the measurement of peripheral neurotoxicity. High content imaging allowed an unbiased assessment of cell morphology and viability. The computational quantification of neurite growth as functional parameter highly sensitive to disturbances by toxicants was used as endpoint reflecting specific neurotoxicity. The differentiation of cells towards dorsal root ganglia neurons was tracked in relation to a large background data set based on gene expression microarrays. On this basis, a peripheral neurotoxicity (PeriTox) test was developed as first toxicological assay that harnesses the potential of human pluripotent stem cells to generate cell types/tissues that are not otherwise available for prediction of human systemic organ toxicity. Testing of more than 30 chemicals showed that human neurotoxicants, as well as neurite growth enhancers, were correctly identified. Various classes of chemotherapeutics causing human peripheral neuropathies were identified, while they were missed when tested on human central neurons. The PeriTox-test established here shows the potential of human stem cells for clinically-relevant safety testing of drugs in use and of new emerging candidates.
Stem Cell-Derived Immature Human Dorsal Root Ganglia Neurons to Identify Peripheral Neurotoxicants.
Sex, Specimen part, Cell line
View SamplesMethod: mRNA profiles were generated from pair-end sequencing of duplicate samples using Illumina Hiseq 2000. Results: Genes with an expression change of more than 2 fold were considered to be differentially expresed Overall design: Macrophages are cells belongs to innate immune system, which response to pathogen by the production of inflammatory proteins those that are effective in both combating pathogen and wound healing. Using microarray approach with BET inhibitors it was shown that many of the inflammatory response genes were under control of BET proteins. Purpose of this study was to assess the effect of BRD4 KO in NGS derived transcriptome profiles of both stimulated and unstimulated macrophages.
BRD4 directs hematopoietic stem cell development and modulates macrophage inflammatory responses.
Treatment, Subject
View SamplesTest systems to identify developmental toxicants are urgently needed. A combination of human stem cell technology and transcriptome analysis was used here to provide proof-of-concept that toxicants with a related mode of action can be identified, and grouped for read-across. We chose a test system of developmental toxicity, related to the generation of neuroectoderm from pluripotent stem cells (UKN1), and exposed cells for six days to benchmark concentration (BMC) of histone deacetylase inhibitors (HDACi) valproic acid, trichostatin-A, vorinostat, belinostat, panobinostat and entinostat. To provide insight into their toxic action, we identified HDACi consensus genes, assigned them to superordinate biological processes, and mapped them to a human transcription factor network constructed from hundreds of transcriptome data sets. We also tested a heterogeneous group of mercurials (methylmercury, thimerosal, mercury(II)chloride, mercury(II)bromide, 4-chloromercuribenzoic acid, phenylmercuric acid) (BMCs). Microarray data were compared at the highest non-cytotoxic concentration for all 12 toxicants. A support vector machine (SVM)-based classifier predicted all HDACi correctly. For validation, the classifier was applied to legacy data sets of HDACi, and for each exposure situation, the SVM predictions correlated with the developmental toxicity. Finally, optimization of the classifier based on 100 probe sets showed that eight genes (F2RL2, TFAP2B, EDNRA, FOXD3, SIX3, MT1E, ETS1, LHX2) are sufficient to separate HDACi from mercurials. Our data demonstrate, how human stem cells and transcriptome analysis can be combined for mechanistic grouping and prediction of toxicants. Extension of this concept to mechanisms beyond HDACi would allow prediction of human developmental toxicity hazard of unknown compounds with the UKN1 test system.
A transcriptome-based classifier to identify developmental toxicants by stem cell testing: design, validation and optimization for histone deacetylase inhibitors.
Sex, Specimen part
View SamplesGPAM is well characterized in triglyceride synthesis, but has never been implicated in cancer. Our study report a role for GPAM in cell migration. Gene expression changes after GPAM silencing was investigated to gain insight into possible mechanisms underlying GPAM's role in cell migration.
Glycerol-3-phosphate Acyltransferase 1 Promotes Tumor Cell Migration and Poor Survival in Ovarian Carcinoma.
Specimen part, Cell line
View SamplesRNA-seq transcriptome analysis identified a functional requirement for zebrafish Rfx4 in the developing neural floor plate and roof plate. Overall design: Embryos derived from an rfx4uw8013/+ incross were sorted by phenotype into mutant and sibling groups. RNA was prepared from each individual embryo at ~ 25 hpf
Zebrafish Rfx4 controls dorsal and ventral midline formation in the neural tube.
No sample metadata fields
View SamplesRNA-seq transcriptome analysis identified an early requirement for zic2 in periocular neural crest as an activator of alx1, a transcription factor with essential roles in craniofacial and ocular morphogenesis in human and zebrafish Overall design: Embryos derived from a zic2aGBT133/+; zic2bUW1127/+ incross were sorted by presence or absence of coloboma. RNA was prepared from each individual embryo at ~ 25 hpf
Zebrafish zic2 controls formation of periocular neural crest and choroid fissure morphogenesis.
No sample metadata fields
View SamplesPrevious studies in our laboratory demonstrated that the azurophil granule protease neutrophil elastase (NE) cleaves PML-RARA (PR), the fusion protein that initiates acute promyelocytic leukemia (APL). Further, NE deficiency reduces the penetrance of APL in a murine model of this disease. We therefore predicted that NE-mediated PR cleavage might be important for its ability to initiate APL. To test this hypothesis, we generated a mouse expressing NE-resistant PR. These mice developed APL indistinguishable from wild type PR, but with significantly reduced latency (median leukemia-free survival of 274 days versus 473 days for wild type PR, p<0.001). Resistance to proteolysis may increase the abundance of full length PR protein in early myeloid cells, and our previous data suggested that non-cleaved PR may be less toxic to early myeloid cells. Together, these effects appear to increase the leukemogenicity of NE-resistant PR, contrary to our previous prediction. We conclude that NE deficiency may reduce APL penetrance via indirect mechanisms that are still NE dependent.
A protease-resistant PML-RAR{alpha} has increased leukemogenic potential in a murine model of acute promyelocytic leukemia.
Cell line
View SamplesThis analysis represents the first comprehensive sampling of germ cells in the developing testis over time, at high-resolution, single-cell depth. From these analyses, we have not only revealed novel genetic regulatory signatures of murine germ cells over time, but have also demonstrated that cell types positive for a single marker gene have the capacity to change dramatically during testis maturation, and therefore cells of a particular “identity” may differ significantly from postnatal to adult life. Overall design: Single-cell suspensions of mammalian testes ranging from PND6 to adult were processed for single-cell RNAseq (10x Genomics Chromium) and libraries were sequenced on a NextSeq500 (Illumina).
Dynamic transcriptome profiles within spermatogonial and spermatocyte populations during postnatal testis maturation revealed by single-cell sequencing.
Age, Disease, Cell line, Subject
View SamplesGlatiramer Acetate (GA) has provided safe and effective treatment for multiple sclerosis (MS) patients for two decades. It acts as an antigen, yet the precise mechanism of action remains to be fully elucidated, and no validated pharmacokinetic or pharmacodynamic biomarkers exist. In order to better characterize GAs biological impact, genome-wide expression studies were conducted with a human monocyte (THP-1) cell line. Consistent with previous literature, branded GA upregulated antiinflammatory markers (e.g. IL10), and modulated multiple immune-related pathways. Despite some similarities, significant differences were observed between expression profiles induced by branded GA and Probioglat, a differently-manufactured glatiramoid purported to be a generic GA.
Gene expression studies of a human monocyte cell line identify dissimilarities between differently manufactured glatiramoids.
Cell line, Treatment, Time
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