Establishment of human pluripotent stem cell-derived cortical neurosphere model to study pathomechanisms and chemical toxicity in Kleefstra syndrome
In the present study,we aimed to establish and characterize a mature cortical spheroid model system for Kleefstra syndrome (KS) using patient-derived iPSC. We identified key differences in the growth behavior of KS spheroids determined by reduced proliferation marked by low Ki67 and high E-cadherin expression. Conversely,in the spheroid-based neurite outgrowth assay KS outperformed the control neurite outgrowth due to higher BDNF expression. KS spheroids were highly enriched in VGLUT1/2-expressing glutamatergic and ChAT-expressing cholinergic neurons,while TH-positive catecholamine neurons were significantly underrepresented. Furthermore,high NMDAR1 expression was also detected in the KS spheroid,similarly to other patients-derived neuronal cultures,denoting high NMDAR1 expression as a general,KS-specific marker. Control and KS neuronal progenitors and neurospheres were exposed to different toxicants (paraquat,rotenone,bardoxolone,and doxorubicin),and dose-response curves were assessed after acute exposure. Differentiation stage and compound-specific differences were detected with KS neurospheres being the most sensitive to paraquat. Altogether this study describes a robust 3D model system expressing the disease-specific markers and recapitulating the characteristic pathophysiological traits. This platform is suitable for testing developing brain-adverse environmental effects interactions,drug development,and screening towards individual therapeutic strategies.Supplementary InformationThe online version contains supplementary material available at 10.1038/s41598-024-72791-4.
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(Jan 2025)
International Journal of Molecular Sciences 26 2
Establishment of iPSC-Derived MSCs Expressing hsa-miR-4662a-5p for Enhanced Immune Modulation in Graft-Versus-Host Disease (GVHD)
The immune-modulatory effects of mesenchymal stromal cells (MSCs) are widely used to treat inflammatory disorders,with indoleamine 2,4-dioxygenase-1 (IDO-1) playing a pivotal role in suppressing stimulated T-cell proliferation. Taking that three-dimensional (3D) cultures enhance MSCs’ anti-inflammatory properties compared with two-dimensional (2D) cultures,the differentially expressed miRNAs were examined. Thus,we identified hsa-miR-4662a-5p (miR-4662a) as a key inducer of IDO-1 via its suppression of bridging integrator-1 (BIN-1),a negative regulator of the IDO-1 gene. The IDO-1-inducing potential of miR-4662a was conserved across primary MSCs from various donors and sources but exhibited variability. Notably,iPSC-derived MSCs (iMSCs) demonstrated superior IDO-1 induction and immune-modulatory efficacy compared with their donor-matched primary MSCs. Accordingly,iMSCs expressing miR-4662a (4662a/iMSC) exhibited stronger suppressive effects on T-cell proliferation and more potent suppressive effects on graft-versus-host disease (GVHD),improving survival rates and reducing tissue damage in the liver and gut. Our results point to the therapeutic potential of standardized,off-the-shelf 4662a/iMSC as a robust immune-modulating cell therapy for GVHD.
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Fraga AM et al. (JAN 2012)
Methods in molecular biology (Clifton,N.J.) 873 1--12
Establishment of new lines of human embryonic stem cells: evolution of the methodology.
Although since 1998 more than 1,200 different hESC lines have been established worldwide,there is still a recognized interest in the establishment of new lines of hESC,particularly from HLA types and ethnic groups underrepresented among the currently available lines. The methodology of hESC derivation has evolved significantly since the initial derivations using human LIF (hLIF) for maintenance of pluripotency. However,there are still a number of alternative strategies for the different steps involved in establishing a new line of hESC. We have analyzed the different strategies/parameters used between 1998 and 2010 for the derivation of the 375 hESC lines able to form teratomas in immunocompromised mice deposited in two international stem cell registries. Here we describe some trends in the methodology for establishing hESC lines,discussing the developments in the field. Nevertheless,we describe a much greater heterogeneity of strategies for hESCs derivation than what is used for murine ESC lines,indicating that optimum conditions have not been identified yet,and thus,hESC establishment is still an evolving field of research.
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Ramalho AC et al. (APR 2002)
European cytokine network 13 1 39--45
Estradiol and raloxifene decrease the formation of multinucleate cells in human bone marrow cultures.
Estrogen (E2) deficiency is responsible for increased bone turnover in the postmenopausal period,and it can be prevented by estrogen replacement therapy. The way estrogen acts on bone cells is not fully understood. Human bone marrow cell cultures may be a reliable model for studying the action of steroids on osteoclastogenesis in vitro. We examine the effects of estradiol and Raloxifene,a selective estrogen receptor modulator,on human primary bone marrow cells cultured for 15 days. 17beta-estradiol and Raloxifene significantly decreased the number of tartrate-resistant acid phosphatase multinucleate cells from osteoclast precursors on day 15. Estrogen receptor alpha (ER-alpha) mRNA was present in bone marrow mononuclear cells cultured for 5 days,but there was no estrogen receptor beta (ER-beta) mRNA,suggesting that this effect was mediated by ER-alpha. 15-day cultures no longer contained ER-alpha mRNA,suggesting that estrogen acts on early events of osteoclast differentiation. Finally,10-8 M 17beta-estradiol has no effect on the release of IL-6 and IL-6-sr into the medium of marrow mononuclear cells cultured for 5 or 15 days. Osteoclast apoptosis was not affected by estradiol or Raloxifene after 15 days of culture under our conditions. In conclusion,we have shown that both estradiol and Raloxifene inhibit osteoclast differentiation in human bone marrow mononuclear cultures. The biological effect that can mimic in vivo differentiation could be mediated through ER-alpha.
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Tam A et al. (JAN 2014)
PloS one 9 6 e100633
Estradiol increases mucus synthesis in bronchial epithelial cells.
Airway epithelial mucus hypersecretion and mucus plugging are prominent pathologic features of chronic inflammatory conditions of the airway (e.g. asthma and cystic fibrosis) and in most of these conditions,women have worse prognosis compared with male patients. We thus investigated the effects of estradiol on mucus expression in primary normal human bronchial epithelial cells from female donors grown at an air liquid interface (ALI). Treatment with estradiol in physiological ranges for 2 weeks caused a concentration-dependent increase in the number of PAS-positive cells (confirmed to be goblet cells by MUC5AC immunostaining) in ALI cultures,and this action was attenuated by estrogen receptor beta (ER-$$) antagonist. Protein microarray data showed that nuclear factor of activated T-cell (NFAT) in the nuclear fraction of NHBE cells was increased with estradiol treatment. Estradiol increased NFATc1 mRNA and protein in ALI cultures. In a human airway epithelial (1HAE0) cell line,NFATc1 was required for the regulation of MUC5AC mRNA and protein. Estradiol also induced post-translational modification of mucins by increasing total fucose residues and fucosyltransferase (FUT-4,-5,-6) mRNA expression. Together,these data indicate a novel mechanism by which estradiol increases mucus synthesis in the human bronchial epithelium.
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(Jan 2025)
Cell Death & Disease 16 1
Estrogen-dependent activation of TRX2 reverses oxidative stress and metabolic dysfunction associated with steatotic disease
Metabolic dysfunction-associated steatotic liver disease (MASLD) encompasses a spectrum of hepatic disorders,ranging from simple steatosis to steatohepatitis,with the most severe outcomes including cirrhosis,liver failure,and hepatocellular carcinoma. Notably,MASLD prevalence is lower in premenopausal women than in men,suggesting a potential protective role of estrogens in mitigating disease onset and progression. In this study,we utilized preclinical in vitro models—immortalized cell lines and hepatocyte-like cells derived from human embryonic stem cells—exposed to clinically relevant steatotic-inducing agents. These exposures led to lipid droplet (LD) accumulation,increased reactive oxygen species (ROS) levels,and mitochondrial dysfunction,along with decreased expression of markers associated with hepatocyte functionality and differentiation. Estrogen treatment in steatotic-induced liver cells resulted in reduced ROS levels and LD content while preserving mitochondrial integrity,mediated by the upregulation of mitochondrial thioredoxin 2 (TRX2),an antioxidant system regulated by the estrogen receptor. Furthermore,disruption of TRX2,either pharmacologically using auranofin or through genetic interference,was sufficient to counteract the protective effects of estrogens,highlighting a potential mechanism through which estrogens may prevent or slow MASLD progression.
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M. E. Luck et al. (feb 2022)
Shock (Augusta,Ga.) 57 2 230--237
Ethanol Intoxication and Burn Injury Increases Intestinal Regulatory T Cell Population and Regulatory T Cell Suppressive Capability.
Traumatic injuries,such as burn,are often complicated by ethanol intoxication at the time of injury. This leads to a myriad of complications and post-burn pathologies exacerbated by aberrant immune responses. Recent findings suggest that immune cell dysfunction in the gastrointestinal system is particularly important in deleterious outcomes associated with burn injuries. In particular,intoxication at the time of burn injury leads to compromised intestinal T cell responses,which can diminish intestinal immunity and promote bacterial translocation,allowing for increased secondary infections in the injured host and associated sequelae,such as multiple organ failure and sepsis. Regulatory T cells (Treg) have been identified as important mediators of suppressing effector T cell function. Therefore,the goal of this study was to assess the effects of ethanol intoxication and burn injury on Treg populations in small intestinal immune organs. We also evaluated the suppressive capability of Tregs isolated from injured animals. Male C57BL/6 mice were gavaged with 2.9?Šg/kg ethanol before receiving a ˆ¼12.5% total body surface area scald burn. One day after injury,we identified a significant increase in Tregs number in small intestine Peyer's patches (ˆ¼?—1.5) and lamina propria (ˆ¼?—2). Tregs-producing cytokine IL-10 were also increased in both tissues. Finally,Tregs isolated from ethanol and burn-injured mice were able to suppress proliferation of effector T cells to a greater degree than sham vehicle Tregs. This was accompanied by increased levels of IL-10 and decreased levels of pro-proliferative cytokine IL-2 in cultures containing ethanol + burn Tregs compared with sham Tregs. These findings suggest that Treg populations are increased in intestinal tissues 1 day following ethanol intoxication and burn injury. Tregs isolated from ethanol and burn-injured animals also exhibit a greater suppression of effector T cell proliferation,which may contribute to altered T cell responses following injury.
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De Filippis L et al. ( 2016)
Molecular brain 9 1 51
Ethanol-mediated activation of the NLRP3 inflammasome in iPS cells and iPS cells-derived neural progenitor cells.
BACKGROUND Alcohol abuse produces an enormous impact on health,society,and the economy. Currently,there are very limited therapies available,largely due to the poor understanding of mechanisms underlying alcohol use disorders (AUDs) in humans. Oxidative damage of mitochondria and cellular proteins aggravates the progression of neuroinflammation and neurological disorders initiated by alcohol abuse. RESULTS Here we show that ethanol exposure causes neuroinflammation in both human induced pluripotent stem (iPS) cells and human neural progenitor cells (NPCs). Ethanol exposure for 24 hours or 7 days does not affect the proliferation of iPS cells and NPCs,but primes an innate immune-like response by activating the NLR family pyrin domain containing 3 (NLRP3) inflammasome pathway. This leads to an increase of microtubule-associated protein 1A/1B-light chain 3(+) (LC3B(+)) autophagic puncta and impairment of the mitochondrial and lysosomal distribution. In addition,a decrease of mature neurons derived from differentiating NPCs is evident in ethanol pre-exposed compared to control NPCs. Moreover,a second insult of a pro-inflammatory factor in addition to ethanol preexposure enhances innate cellular inflammation in human iPS cells. CONCLUSIONS This study provides strong evidence that neuronal inflammation contributes to the pathophysiology of AUDs through the activation of the inflammasome pathway in human cellular models.
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I. Koprivica et al. ( 2018)
Frontiers in immunology 9 3130
Ethyl Pyruvate Stimulates Regulatory T Cells and Ameliorates Type 1 Diabetes Development in Mice.
Type 1 diabetes (T1D) is an autoimmune disease in which a strong inflammatory response causes the death of insulin-producing pancreatic beta-cells,while inefficient regulatory mechanisms allow that response to become chronic. Ethyl pyruvate (EP),a stable pyruvate derivate and certified inhibitor of an alarmin-high mobility group box 1 (HMGB1),exerts anti-oxidant and anti-inflammatory properties in animal models of rheumatoid arthritis and encephalomyelitis. To test its therapeutic potential in T1D,EP was administered intraperitoneally to C57BL/6 mice with multiple low-dose streptozotocin (MLDS)-induced T1D. EP treatment decreased T1D incidence,reduced the infiltration of cells into the pancreatic islets and preserved beta-cell function. Apart from reducing HMGB1 expression,EP treatment successfully interfered with the inflammatory response within the local pancreatic lymph nodes and in the pancreas. Its effect was restricted to boosting the regulatory arm of the immune response through up-regulation of tolerogenic dendritic cells (CD11c+CD11b-CD103+) within the pancreatic infiltrates and through the enhancement of regulatory T cell (Treg) levels (CD4+CD25highFoxP3+). These EP-stimulated Treg displayed enhanced suppressive capacity reflected in increased levels of CTLA-4,secreted TGF-beta,and IL-10 and in the more efficient inhibition of effector T cell proliferation compared to Treg from diabetic animals. Higher levels of Treg were a result of increased differentiation and proliferation (Ki67+ cells),but also of the heightened potency for migration due to increased expression of adhesion molecules (CD11a and CD62L) and CXCR3 chemokine receptor. Treg isolated from EP-treated mice had the activated phenotype and T-bet expression more frequently,suggesting that they readily suppressed IFN-gamma-producing cells. The effect of EP on Treg was also reproduced in vitro. Overall,our results show that EP treatment reduced T1D incidence in C57BL/6 mice predominantly by enhancing Treg differentiation,proliferation,their suppressive capacity,and recruitment into the pancreas.
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Bueno C et al. (SEP 2009)
Carcinogenesis 30 9 1628--37
Etoposide induces MLL rearrangements and other chromosomal abnormalities in human embryonic stem cells.
MLL rearrangements are hallmark genetic abnormalities in infant leukemia known to arise in utero. They can be induced during human prenatal development upon exposure to etoposide. We also hypothesize that chronic exposure to etoposide might render cells more susceptible to other genomic insults. Here,for the first time,human embryonic stem cells (hESCs) were used as a model to test the effects of etoposide on human early embryonic development. We addressed whether: (i) low doses of etoposide promote MLL rearrangements in hESCs and hESCs-derived hematopoietic cells; (ii) MLL rearrangements are sufficient to confer hESCs with a selective growth advantage and (iii) continuous exposure to low doses of etoposide induces hESCs to acquire other chromosomal abnormalities. In contrast to cord blood-derived CD34(+) and hESC-derived hematopoietic cells,exposure of undifferentiated hESCs to a single low dose of etoposide induced a pronounced cell death. Etoposide induced MLL rearrangements in hESCs and their hematopoietic derivatives. After long-term culture,the proportion of hESCs harboring MLL rearrangements diminished and neither cell cycle variations nor genomic abnormalities were observed in the etoposide-treated hESCs,suggesting that MLL rearrangements are insufficient to confer hESCs with a selective proliferation/survival advantage. However,continuous exposure to etoposide induced MLL breaks and primed hESCs to acquire other major karyotypic abnormalities. These data show that chronic exposure of developmentally early stem cells to etoposide induces MLL rearrangements and make hESCs more prone to acquire other chromosomal abnormalities than postnatal CD34(+) cells,linking embryonic genotoxic exposure to genomic instability.
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ETS2 and ERG promote megakaryopoiesis and synergize with alterations in GATA-1 to immortalize hematopoietic progenitor cells.
ETS2 and ERG are transcription factors,encoded on human chromosome 21 (Hsa21),that have been implicated in human cancer. People with Down syndrome (DS),who are trisomic for Hsa21,are predisposed to acute megakaryoblastic leukemia (AMKL). DS-AMKL blasts harbor a mutation in GATA1,which leads to loss of full-length protein but expression of the GATA-1s isoform. To assess the consequences of ETS protein misexpression on megakaryopoiesis,we expressed ETS2,ERG,and the related protein FLI-1 in wild-type and Gata1 mutant murine fetal liver progenitors. These studies revealed that ETS2,ERG,and FLI-1 facilitated the expansion of megakaryocytes from wild-type,Gata1-knockdown,and Gata1s knockin progenitors,but none of the genes could overcome the differentiation block characteristic of the Gata1-knockdown megakaryocytes. Although overexpression of ETS proteins increased the proportion of CD41(+) cells generated from Gata1s-knockin progenitors,their expression led to a significant reduction in the more mature CD42 fraction. Serial replating assays revealed that overexpression of ERG or FLI-1 immortalized Gata1-knockdown and Gata1s knockin,but not wild-type,fetal liver progenitors. Immortalization was accompanied by activation of the JAK/STAT pathway,commonly seen in megakaryocytic malignancies. These findings provide evidence for synergy between alterations in GATA-1 and overexpression of ETS proteins in aberrant megakaryopoiesis.
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Lindgren AG et al. (JAN 2015)
Cell regeneration (London,England) 4 1 1
ETV2 expression increases the efficiency of primitive endothelial cell derivation from human embryonic stem cells.
BACKGROUND: Endothelial cells line the luminal surface of blood vessels and form a barrier between the blood and other tissues of the body. Ets variant 2 (ETV2) is transiently expressed in both zebrafish and mice and is necessary and sufficient for vascular endothelial cell specification. Overexpression of this gene in early zebrafish and mouse embryos results in ectopic appearance of endothelial cells. Ectopic expression of ETV2 in later development results in only a subset of cells responding to the signal.backslashnbackslashnFINDINGS: We have examined the expression pattern of ETV2 in differentiating human embryonic stem cells (ESCs) to determine when the peak of ETV2 expression occurs. We show that overexpression of ETV2 in differentiating human ESC is able to increase the number of endothelial cells generated when administered during or after the endogenous peak of gene expression.backslashnbackslashnCONCLUSIONS: Addition of exogenous ETV2 to human ESCs significantly increased the number of cells expressing angioblast genes without arterial or venous specification. This may be a viable solution to generate in vitro endothelial cells for use in research and in the clinic.
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