This SuperSeries is composed of the SubSeries listed below.
Using transcriptomics to guide lead optimization in drug discovery projects: Lessons learned from the QSTAR project.
Cell line, Treatment
View SamplesIn this paper we demonstrated the potential to flag toxicity issues by utilizing data from exploratory experiments which are typically generated for target evaluation purposes during early drug discovery
Using transcriptomics to guide lead optimization in drug discovery projects: Lessons learned from the QSTAR project.
Cell line, Treatment
View SamplesIn this paper we demonstrated the potential to flag toxicity issues by utilizing data from exploratory experiments which are typically generated for target evaluation purposes during early drug discovery
Using transcriptomics to guide lead optimization in drug discovery projects: Lessons learned from the QSTAR project.
Cell line, Treatment
View SamplesIn this paper we demonstrated the potential to flag toxicity issues by utilizing data from exploratory experiments which are typically generated for target evaluation purposes during early drug discovery
Using transcriptomics to guide lead optimization in drug discovery projects: Lessons learned from the QSTAR project.
Cell line, Treatment
View SamplesWe analysed the capacity of THP-1 cells (differentiated to macrophagoid cells) to recognize RNA sequences via pattern recognition receptors in vitro. Gene expression was analysed by RNA-Microarray. Cytokine production was analysed by ELISA assays.
Human TLR8 senses UR/URR motifs in bacterial and mitochondrial RNA.
Cell line, Treatment
View SamplesPlasmacytoid dendritic cells (pDC) efficiently produce large amounts of type I interferon in response to TLR7 and TLR9 ligands, whereas conventional DCs (cDC) predominantly secrete high levels of the cytokines IL-10 and IL-12. The molecular basis underlying this distinct phenotype is not well understood. Here, we identified the MAPK phosphatase Dusp9/MKP-4 by transcriptome analysis as selectively expressed in pDC, but not cDC. We confirmed the constitutive expression of Dusp9 at the protein level in pDC generated in vitro by culture with Flt3L and ex vivo in sorted splenic pDC. Dusp9 expression was low in B220- bone marrow precursors and was up-regulated during pDC differentiation, concomitant with established pDC markers. Higher expression of Dusp9 in pDC correlated with impaired phosphorylation of the MAPK ERK1/2 upon TLR9 stimulation. Notably, Dusp9 was not expressed at detectable levels in human pDC, although these displayed similarly impaired activation of ERK1/2 MAPK compared to cDC. Enforced retroviral expression of Dusp9 in mouse GM-CSF-induced cDC increased the expression of TLR7/9-induced IL-12p40 and IFNwhereas IL-10 levels were diminished. Taken together, our results suggest that the species-specific, selective expression of Dusp9 in murine pDC contributes to the differential cytokine/interferon output of pDC and cDC.
Selective Expression of the MAPK Phosphatase Dusp9/MKP-4 in Mouse Plasmacytoid Dendritic Cells and Regulation of IFN-β Production.
No sample metadata fields
View SamplesCellular reprogramming from somatic cells to induced pluripotent stem cells (iPSCs) can be achieved through forced expression of the transcription factors Oct4, Klf4, Sox2 and c-Myc (OKSM). These factors, in combination with environmental cues, induce a stable intrinsic pluripotency network that confers indefinite self-renewal capacity on iPSCs. In addition to Oct4 and Sox2, the homeodomain-containing transcription factor Nanog is an integral part of the pluripotency network. Although Nanog expression is not required for the maintenance of pluripotent stem cells, it has been reported to be essential for the establishment of both embryonic stem cells (ESCs) from blastocysts and iPSCs from somatic cells. Here we revisit the role of Nanog in direct reprogramming. Surprisingly, we find that Nanog is dispensable for iPSC formation under optimized culture conditions. We further document that Nanog-deficient iPSCs are transcriptionally highly similar to wild-type iPSCs and support the generation of teratomas and chimeric mice. Lastly, we provide evidence that the presence of ascorbic acid in the culture media is critical for overcoming the previously observed reprogramming block of Nanog knockout cells.
Nanog is dispensable for the generation of induced pluripotent stem cells.
Specimen part
View SamplesDirect reprogramming of human fibroblasts to a pluripotent state has been achieved through ectopic expression of the transcription factors OCT4, SOX2, and either cMYC and KLF4 or NANOG and LIN28. Little is known, however, about the mechanisms by which reprogramming occurs, which is in part limited by the low efficiency of conversion. To this end, we sought to create a doxycycline-inducible lentiviral system to convert primary human fibroblasts and keratinocytes into human induced pluripotent stem (hiPS) cells. hiPS cells generated with this system were molecularly and functionally similar to human embryonic stem (hES) cells, demonstrated by gene expression profiles, DNA methylation status, and differentiation potential. While expression of the viral transgenes was required for several weeks in fibroblasts, we found that 10 days was sufficient for the reprogramming of keratinocytes, suggesting that the kinetics of reprogramming are cell-type dependent. Using our inducible system, we developed a strategy to induce hiPS cell formation at high frequency by generating differentiated cells that contain the viral transgenes in a pattern that enables successful induction of pluripotency. Upon addition of doxycycline to differentiated hiPS-derived cells, we obtained secondary hiPS cells at a frequency at least 100-fold greater than the initial conversion. The ability to reprogram cells with high efficiency provides a unique platform to dissect the underlying molecular and biochemical processes that accompany nuclear reprogramming.
A high-efficiency system for the generation and study of human induced pluripotent stem cells.
No sample metadata fields
View SamplesTo assess the role of the aryl hydrocarbon receptor (AHR) receptor in dendritic epidermal T cells (DETC), we sorted DETC from 2 weeks old mice homozygous and heterozygous for AHR-knockout. While DETC are not maintained in the epidermis of mice with a homozygous AHR-knockout, those in heterozygous mice devellop normally. The age at 2 weeks is critical for the DETC establishment and the peak time of the so-called proliferation burst of DETC in wildtype mice. DETC were identified in epidermal cell suspension by expression of the gamma-delta T cell receptor. The DETC proportion of live epidermal cells was between 10-15 % in Ahr-het and 2-4 % in Ahr-ko mice. After FACS-sorting to a purity of 90-98 %, DETC were lysed and their RNA was extracted. Three RNA samples for each genotype were generated, by pooling the RNA of 2-3 mice for each sample. RNA was processed and hybridized to Applied BiosystemsTM ClariomTM S Mouse Gene Expression Microarrays. Using the Software package R the data were normalized using the Robust Multichip Average algorithm (RMA) and significance of differentially regulated genes was assessed by the False Discovery Rate (FDR) using the Benjamini and Hochberg’s method.
The small chain fatty acid butyrate antagonizes the TCR-stimulation-induced metabolic shift in murine epidermal gamma delta T cells.
Age, Specimen part
View SamplesThe reprogramming of somatic cells into induced pluripotent stem cells (iPSCs) upon overexpression of OCT4, KLF4, SOX2 and c-MYC (OKSM) provides a powerful system to interrogate basic mechanisms of cell fate change. However, iPSC formation with standard methods is typically protracted and inefficient, resulting in heterogeneous cell populations. We show that exposure of OKSM-expressing cells to both ascorbic acid and a GSK3- inhibitor (AGi) facilitates more synchronous and rapid iPSC formation from several mouse cell types. AGi treatment restored the ability of refractory cell populations to yield iPSC colonies, and it attenuated the activation of developmental regulators commonly observed during the reprogramming process. Moreover, AGi supplementation gave rise to chimera-competent iPSCs after as little as 48 h of OKSM expression. Our results offer a simple modification to the reprogramming protocol, facilitating iPSC induction at unparalleled efficiencies and enabling dissection of the underlying mechanisms in more homogeneous cell populations.
Small molecules facilitate rapid and synchronous iPSC generation.
Specimen part, Treatment, Time
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