Embryonic stem cell

The pathogenesis of Dupuytren's disease (DD) remains unclear although there is increasing evidence supporting the role of stem cells in this and other fibrotic conditions. This review examines the role of DD tissue-associated embryonic stem cells (ESCs) and mesenchymal stem cells (MSCs), and circulating fibrocytes and circulating MSCs, in the biology of DD. It is exciting to infer that dysfunction of an upstream ESC-like population within the affected tissue leads to the downstream development and proliferation of aberrant myofibroblasts through a putative MSC intermediate...

Muscarinic acetylcholine receptors (mAchRs), which are expressed in various embryonic cells, may regulate neuronal differentiation. In the present study, we examined the effects of mAchR stimulation on the differentiation of mouse induced pluripotent stem (iPS) cells into neural progenitor cells (NPCs). Mouse iPS cells were cultured on ultra-low attachment dishes to induce embryoid body (EB) formation. All-trans retinoic acid (ATRA, 3 µM) and/ or pilocarpine (10 or 100 µM), a mAchR agonist, were added to EB cultures for 4 days, following which the EBs were cultured on gelatin-coated plates for 7 days...

The transition of hematopoiesis from the fetal liver (FL) to the bone marrow (BM) is incompletely characterized. We demonstrate that the Wiskott-Aldrich syndrome verprolin-homologous protein (WAVE) complex 2 is required for this transition, as complex degradation via deletion of its scaffold Hem-1 causes the premature exhaustion of neonatal BM hematopoietic stem cells (HSCs). This exhaustion of BM HSC is due to the failure of BM engraftment of Hem-1-/- FL HSCs, causing early death. The Hem-1-/- FL HSC engraftment defect is not due to the lack of the canonical function of the WAVE2 complex, the regulation of actin polymerization, because FL HSCs from Hem-1-/- mice exhibit no defects in chemotaxis, BM homing, or adhesion...

Many mammalian genes are transcribed during short bursts of variable frequencies and sizes that substantially contribute to cell-to-cell variability. However, which molecular mechanisms determine bursting properties remains unclear. To probe putative mechanisms, we combined temporal analysis of transcription along the circadian cycle with multiple genomic reporter integrations, using both short-lived luciferase live microscopy and single-molecule RNA-FISH. Using the Bmal1 circadian promoter as our model, we observed that rhythmic transcription resulted predominantly from variations in burst frequency, while the genomic position changed the burst size...

Bivalent chromatin domains containing repressive H3K27me3 and active H3K4me3 modifications are barriers for the expression of lineage-specific genes in ES cells and must be resolved for the transcription induction of these genes during differentiation, a process that remains largely unknown. Here, we show that Asf1a, a histone chaperone involved in nucleosome assembly and disassembly, regulates the resolution of bivalent domains and activation of lineage-specific genes during mouse ES cell differentiation. Deletion of Asf1a does not affect the silencing of pluripotent genes, but compromises the expression of lineage-specific genes during ES cell differentiation...

In this study, we used comparative genomics and developmental genetics to identify epigenetic regulators driving oncogenesis in a zebrafish retinoblastoma 1 ( rb1 ) somatic-targeting model of RB1 mutant embryonal brain tumors. Zebrafish rb1 brain tumors caused by TALEN or CRISPR targeting are histologically similar to human central nervous system primitive neuroectodermal tumors (CNS-PNETs). Like the human oligoneural OLIG2+/SOX10+ CNS-PNET subtype, zebrafish rb1 tumors show elevated expression of neural progenitor transcription factors olig2 , sox10 , sox8b and the receptor tyrosine kinase erbb3a oncogene...

In an effort to increase efficiency in the creation of genetically modified mice via ES Cell methodologies, we present an adaptation to the current blastocyst injection protocol. Here we report that a simple rotation of the embryo, and injection through Trans-Inner cell mass (TICM) increased the percentage of chimeric mice from 31% to 50%, with no additional equipment or further specialized training. 26 different inbred clones, and 35 total clones were injected over a period of 9 months. There was no significant difference in either pregnancy rate or recovery rate of embryos between traditional injection techniques and TICM...

Embryonic stem (ES) cells have the potential to differentiate into any of the three germ layers (endoderm, mesoderm, or ectoderm), and can generate many lineages for regenerative medicine. ES cell culture in vitro has long been the subject of widespread concerns. Classically, mouse ES cells are maintained in serum and leukemia inhibitory factor (LIF)-containing medium. However, under serum/LIF conditions, cells show heterogeneity in morphology and the expression profile of pluripotency-related genes, and are mostly in a metastable state...

Per- and polyfluoroalkyl substances (PFASs) represent a highly ubiquitous group of synthetic chemicals used in products ranging from water and oil repellents and lubricants to firefighting foam. These substances can enter and accumulate in multiple tissue matrices in up to 100% of people assessed. Though animal models strongly identify these compounds as male reproductive toxicants, with exposed rodents experiencing declines in sperm count, alterations in hormones, and DNA damage in spermatids, among other adverse outcomes, human studies report conflicting conclusions as to the reproductive toxicity of these chemicals...

Clinical application of stem cell derivatives requires clinical-grade cells and sufficient preclinical proof of safety and efficacy, preferably in primates. We previously successfully established a clinical-grade human parthenogenetic embryonic stem cell (hPESC) line, but the suitability of its subtype-specific progenies for therapy is not clear. Here, we compared the function of clinical-grade hPESC-derived midbrain dopaminergic (DA) neurons in two canonical protocols in a primate Parkinson's disease (PD) model...

In this study, we deep-sequenced the mtDNA of human embryonic and induced pluripotent stem cells (hESCs and hiPSCs) and their source cells and found that the majority of variants pre-existed in the cells used to establish the lines. Early-passage hESCs carried few and low-load heteroplasmic variants, similar to those identified in oocytes and inner cell masses. The number and heteroplasmic loads of these variants increased with prolonged cell culture. The study of 120 individual cells of early- and late-passage hESCs revealed a significant diversity in mtDNA heteroplasmic variants at the single-cell level and that the variants that increase during time in culture are always passenger to the appearance of chromosomal abnormalities...

Pluripotent stem cells (PSCs) represent the most promising clinical source for regenerative medicine. However, given the cellular heterogeneity within cultivation and safety concerns, the development of specific and efficient tools to isolate a pure population and eliminate all residual undifferentiated PSCs from differentiated derivatives is a prerequisite for clinical applications. In this study, we raised a monoclonal antibody and identified its target antigen as desmoglein-2 (DSG2). DSG2 co-localized with human PSC (hPSC)-specific cell surface markers, and its expression was rapidly downregulated upon differentiation...

During reprogramming, telomere re-elongation is important for pluripotency acquisition and ensures the high quality of induced pluripotent stem cells (iPSCs), but the regulatory mechanism remains largely unknown. Our study showed that fully reprogrammed mature iPSCs or mouse embryonic stem cells expressed higher levels of miR-590-3p and miR-590-5p than pre-iPSCs. Ectopic expression of either miR-590-3p or miR-590-5p in pre-iPSCs improved telomere elongation and pluripotency. Activin receptor II A (Acvr2a) is the downstream target and mediates the function of miR-590...

Neural stem cells (NSCs) are a prominent cell source for understanding neural pathogenesis and for developing therapeutic applications to treat neurodegenerative disease because of their regenerative capacity and multipotency. Recently, a variety of cellular reprogramming technologies have been developed to facilitate in vitro generation of NSCs, called induced NSCs (iNSCs). However, the genetic safety aspects of established virus-based reprogramming methods have been considered, and non-integrating reprogramming methods have been developed...

Tissue engineering, as a novel transplantation therapy, aims to create biomaterial scaffolds resembling the extracellular matrix in order to regenerate the damaged tissues. Adding bioactive factors to the scaffold would improve cell-tissue interactions. In this study, the effect of chitosan poly vinyl alcohol nanofibers containing carbon nanotube scaffold with or without active bioglass (BG+ /BG- ), in combination with neonatal rat brain extract (NRBE) on cell viability, proliferation and neural differentiation of P19 embryonic carcinoma (EC) stem cells was investigated...

Stem cell differentiation can be regulated by biophysical cues such as nanotopography. It involves sensing and integration of these biophysical cues into their transcriptome with a mechanism that is yet to be discovered. In addition to the cytoskeletal and focal adhesion remodeling, nanotopography has also been shown to modulate nucleus morphology. Here, we studied the effect of nanotopography on the temporal changes in nuclei of human embryonic stem cells (hESCs) and human mesenchymal stem cells (hMSCs). Using a high throughput Multi-architecture (MARC) chip analysis, the circularity of the stem cell nuclei changed significantly on different patterns...

Adult newts can regenerate large parts of their brain from adult neural stem cells (NSCs), but how adult NSCs reorganize brain structures during regeneration remains unclear. In development, elaborate brain structures are produced under broadly coordinated regulations of embryonic NSCs in the neural tube, whereas brain regeneration entails exquisite control of the reestablishment of certain brain parts, suggesting a yet-unknown mechanism directs NSCs upon partial brain excision. Here we report that upon one-quarter excision of the adult newt ( Pleurodeles waltl ) mesencephalon, active participation of local NSCs around specific brain subregions' boundaries leads to some imperfect and some perfect brain regeneration along an individual's rostrocaudal axis...

Human lymphoblast cells from a male diagnosed with Alzheimer's disease (AD) expressing the TREM2 p.R47H variant were used to generate integration-free induced pluripotent stem cells (iPSCs) by over-expressing episomal-based plasmids harbouring OCT4, SOX2, KLF4, LIN28, L-MYC and p53 shRNA. The derived iPSC line - AD-TREM2-3 was defined as pluripotent based on (i) expression of pluripotency-associated markers (ii) embryoid body-based differentiation into cell types representative of the three germ layers and (iii) the similarity between the transcriptome of the iPSC line and the human embryonic stem cell line H1 with a Pearson correlation of 0...

Cyclin-dependent kinase 1 (Cdk1) is indispensable for embryonic stem cell (ESC) maintenance and embryo development. Even though some reports have described a connection between Cdk1 and Oct4, there is no evidence that Cdk1 activity is directly linked to the ESC pluripotency transcription program. We recently reported that Aurkb/PP1-mediated Oct4 resetting is important to cell cycle maintenance and pluripotency in mouse ESCs (mESCs). In this study, we show that Cdk1 is an upstream regulator of the Oct4 phosphorylation state during cell cycle progression, and it coordinates the chromatin associated state of Oct4 for pluripotency-related gene expression within the cell cycle...

The scaffolds accompanied with stem cells have great potential for applications in neural tissue engineering. Fabrication of Nano fibrous scaffold similar to extracellular matrix is one of the applicable methods in neural tissue regeneration. The aim of this study was the fabrication of a silk Nano fibrous scaffold as a microenvironment for neural guiding differentiation of Embryonic stem like cells (ES Like cells) derived from testis toward neuron-like cells. ES Like derived from culturing of testicular cells in vitro, were seeded on Silk scaffolds and induced to neuronal phenotype using 4-/4± RA technique following culturing the cells in the neurobasal medium supplemented with 20 ng/ml bFGF,10 ng/ml EGF, B27 and N2 for 8-12 days...